One of the last of the air duels to be fought under the practices which made early air service so vividly recall the age of chivalry, was that in which Captain Immelman, "The Falcon," of the German army, met Captain Ball of the British Royal Flying Corps. Immelman had a record of fifty-one British airplanes downed. Captain Ball was desirous of wiping out this record and the audacious German at the same time, and so flying over the German lines he dropped this letter:

CAPTAIN IMMELMAN:

I challenge you to a man-to-man fight to take place this afternoon at two o'clock. I will meet you over the German lines. Have your anti-air craft guns withhold their fire, while we decide which is the better man. The British guns will be silent.

BALL.

Presently thereafter this answer was dropped from a German airplane:

CAPTAIN BALL:

Your challenge is accepted. The guns will not interfere. I will meet you promptly at two.

IMMELMAN.

The word spread far and wide along the trenches on both sides. Tacitly all firing stopped as though the bugles had sung truce. Men left cover and clambered up on the top to watch the duel. Punctually both flyers rose from their lines and made their way down No Man's Land. Let an eye witness tell the story:

From our trenches there were wild cheers for Ball. The Germans yelled just as vigorously for Immelman.

The cheers from the trenches continued; the Germans increased in volume; ours changed into cries of alarm.

Ball, thousands of feet above us and only a speck in the sky, was doing the craziest things imaginable. He was below Immelman and was apparently making no effort to get above him, thus gaining the advantage of position. Rather he was swinging around, this way and that, attempting, it seemed, to postpone the inevitable.

We saw the German's machine dip over preparatory to starting the nose dive.

"He's gone now," sobbed a young soldier, at my side, for he knew Immelman's gun would start its raking fire once it was being driven straight down.

Then in a fraction of a second the tables were turned. Before Immelman's plane could get into firing position, Ball drove his machine into a loop, getting above his adversary and cutting loose with his gun and smashing Immelman by a hail of bullets as he swept by.

Immelman's airplane burst into flames and dropped. Ball, from above, followed for a few hundred feet and then straightened out and raced for home. He settled down, rose again, hurried back, and released a huge wreath of flowers, almost directly over the spot where Immelman's charred body was being lifted from a tangled mass of metal.

Four days later Ball too was killed.

But the Germans, too, had their champion airmen, mighty fliers, skillful at control and with the machine gun, in whose triumphs they took the same pride that our boys in France did in those of Chapman, Rockwell or Thaw, the British in Warneford, or the French in Guynemer. Chief of these was Captain Boelke, who came to his death in the latter part of 1917, after putting to his credit over sixty Allied planes brought down. A German account of one of his duels as watched from the trenches, will be of interest:

For quite a long time an Englishman had been making circles before our eyes—calmly and deliberately.... My men on duty clenched their fists in impotent wrath. "The dog—!" Shooting would do no good.

Then suddenly from the rear a harsh, deep singing and buzzing cuts the air. It sounds like a German flyer. But he is not yet visible. Only the buzz of an approaching motor is heard in the clouds in the direction of the Englishman. More than a hundred eyes scanned the horizon. There! Far away and high among the clouds is a small black humming bird—a German battle aeroplane. Its course is laid directly for the hostile biplane and it flies like an arrow shot with a clear eye and steady hand. My men crawl out of the shelters. I adjust my field glasses. A lump rises in our throats as if we are awaiting something new and wonderful.

So far the other does not seem to have noticed or recognized the black flyer that already is poised as a hawk above him. All at once there is a mighty swoop through the air like the drop of a bird of prey, and in no time the black flyer is immediately over the Englishman and the air is filled with the furious crackling of a machine gun, followed by the rapid ta-ta-ta of two or three more, all operated at the highest speed just as during a charge. The Englishman drops a little, makes a circle and tries to escape toward the rear. The other circles and attacks him in front, and again we hear the exciting ta-ta-ta! Now the Englishman tries to slip from under his opponent, but the German makes a circle and the effort fails. Then the enemy describes a great circle and attempts to rise above the German. The latter ascends in sharp half circles and again swoops down upon the biplane, driving it toward the German trenches.

Will the Englishman yield so soon? Scattered shouts of joy are already heard in our ranks. Suddenly he drops a hundred yards and more through the air and makes a skillful loop toward the rear. Our warrior of the air swoops after him, tackles him once more and again we hear the wild defiant rattle of the machine guns over our heads. Now they are quite close to our trenches. The French infantry and artillery begin firing in a last desperate hope. Neither of them is touched. Sticking close above and behind him the German drives the Englishman along some six hundred yards over our heads and then just above the housetops of St. A. Once more we hear a distant ta-ta-ta a little slower and more scattered and then as they drop both disappear from our view.

Scarcely five minutes pass before the telephone brings up this news: Lieutenant Boelke has just brought down his seventh flyer.

Methods of air-fighting were succinctly described in a hearing before the Senate Committee on Military Affairs, in June, 1917. The officers testifying were young Americans of the Lafayette Escadrille of the French army. To the civilian the testimony is interesting for the clear idea it gives of military aviation. The extracts following are from the official record:

Adjt. Prince: Senator, there are about four kinds of machines used abroad on the western front to-day. The machines that Adjt. Rumsey and myself are looking after are called the battle machines. Then there are the photography machines, machines that go up to enable the taking of photographs of the German batteries, go back of the line and take views of the country behind their lines and find out what their next line of attack will be, or, if they retreat from the present line, then everything in that way. Probably we have, where we are, in my group alone, a hundred and fifty photographers who do nothing all day long except develop pictures, and you can get pictures of any part of the country that you want. When the Germans retreated from the old line where they used to be, by Peronne and Chaulnes, we had absolute pictures of all the Hindenburg line from where they are now right down to St. Quentin, down to the line the French are on. We had photographs of it all.

Senator Kirby: When they started on the retreat?



Adjt. Prince: Yes, sir. So we knew exactly where their stand would be made. Then, besides that, those photograph machines do a lot of scouting. They have a pilot and a photographer aboard. He has not only a camera, but quite often he has a Lewis gun with him in order to ward off any hostile airmen if they should get through the battle planes that are above him; in other words, should get through us in order to fight him. They do a great deal of the scouting, because they fly at a lower level. The battle planes go up to protect photography machines, or to go man-hunting, as it is called; in other words, to fight the Germans. We fly all day, like to-day, as high as we can go, or as high as the French go as a rule, about 5500 metres, about 17,000 to 18,000 feet.



Adjt. Rumsey: I think 5500 metres is about 19,000 feet. Some go up 6000 metres, which makes about 20,000 feet.

Adjt. Prince: We go up there, and we have a certain sector of the front to look after. If we are only man-hunting, we go backward and forward like a policeman to prevent the Germans from getting over our own lines. We usually fly by fours, if we can, and the four go out together, so as not to be alone. We are usually fighting inside of the German lines, because the morale of the French and English is better than that of the Germans to-day; and every fight I have had—I have never been lucky enough to have one inside of my own lines—they have all been inside of the German lines.

Senator Kirby: What is the equipment of a battle plane such as you use?

Adjt. Prince: I use the 180 horse-power machine. It is called a "S. P. A. D.," which has a Spanish motor. But a great many of the motors to-day are being built here in America.

Senator Kirby: How many men do you carry?

Adjt. Prince: We go up alone in these machines. We did have two guns. We had the Lewis gun on our upper wing and the Vickers down below, that shoots through the propeller as the propeller turns around. Then we gave up the Lewis above. It added more weight, and we did not need it so much. The trouble with the Lewis gun is that it has only ninety-seven cartridges, while the Vickers has five hundred, and you can do just as much damage with the Vickers as you could with them both.

Senator Sutherland: You drive and fight at the same time?

Adjt. Prince: Yes, sir.

Adjt. Rumsey: The machine gun is fixed.

Adjt. Prince: It is absolutely fixed on the machine, and if I should want to adjust it to shoot you, I would adjust my machine on you.

The witness then took up the nature and work of some of the heavier machines. He testified:

Adjt. Prince: Then comes the artillery regulating machine. That machine goes up, and it may be a Farman or a bi-motor, or some other kind of heavier machine, a machine that goes slowly. They go over a certain spot. They have a driver, who is a pilot, like ourselves; then they have an artillery officer on board, whose sole duty it is to send back word, mostly by Marconi, to his battery where the shots are landing. He will say: "Too far," "Too short," "Right," or "Left," and he stays there over this battery until the work done by the French guns has been absolutely controlled, and above him he has some of these battle planes keeping him from being attacked from above by German airmen. Of course, they may be shot at by anti-aircraft guns, which you can not help. That is artillery regulating.

The Chairman: Are you always attacked from above?

Adjt. Prince: By airplanes; yes, sir. It is always much safer to attack from above.

Then you have the bomb-dropping machines, which carry a lot of weight. They go out sometimes in the daytime, but mostly at night, and they have these new sights by which they can stay up quite high in the air and still know the spot they are going at. They know the wind speed, they know their height, and they can figure out by this new arrangement they have exactly when the time is to let go their bombs.

Senator Kirby: Something in the nature of a range-finder?

Adjt. Prince: A sort of range-finder.

Adjt. Rumsey: It is a sort of telescope that looks down between your legs, and you have to regulate yourself, observing your speed, and when you see the spot, you have to touch a button and off go these things.

Adjt. Rumsey: In a raid my brother went on there were sixty-eight machines that left; the French heavy machines, the English heavy machines, and then the English sort of half-fighting machine and half-bombing machine. They call it a Sopwith, and it is a very good machine. They went over there, and the first ones over were the Frenchmen, and they dropped bombs on these Mauser works, and the only thing that the English saw was a big cloud of smoke and dust, and they could not see the works so they just dropped into them. Out of that raid the fighting machines got eight Germans and dropped them, and the Germans got eight Frenchmen. So, out of sixty-eight they lost eight, but we also got eight Germans and dropped six tons of this stuff, which is twenty times as strong as the melinite. We do not know what the name of the powder is. The fighting machines on that trip only carried gasolene for two hours, and the other ones carried it for something like six hours, so we escorted them out for an hour, came back to our lines, filled up with gasolene, went out and met them and brought them back over the danger zone.

Adjt. Prince: Near the trenches is where the danger zone is, because there the German fighting machines are located.

Senator Kirby: How far was it from your battle front that you went?

Adjt. Rumsey: I think it was about 500 miles, 250 there and 250 back; it was between 200 and 250 miles there.

Senator Kirby: Beyond the battle front?

Adjt. Rumsey: Yes; or, to be more accurate, I think it was nearer 200 than 250.

The Chairman: What do you think of the function of the airplane as a determining factor?

Adjt. Prince: There is no doubt that if we could send over in huge waves a great number of these bomb-dropping machines, and simply lay the country waste—for instance, the big cities like Strassburg, Freiburg, and others—not only would the damage done be great, but I guess the popular opinion in Germany, everything being laid waste, would work very strongly in the minds of the public toward having peace. I do not think you could destroy an army, because you could not see them, but you could go to different stations; you could go to Strassburg, to Brussels, and places like that.

The Chairman: Then, sending them over in enormous numbers would also put out of business their airplanes, and they would be helpless, would they not?

Adjt. Prince: Absolutely. You not only have on the front a large number of bomb-dropping machines, but a large number of fighting machines. When the Somme battle was started in the morning the Germans knew, naturally, that the French and British were going to start the Somme drive, and they had up these Drachens, these observation balloons, and the first eighteen minutes that the battle started the French and the English, I think, got twenty-one "saucisse"; in other words, for the next five days there was not a single German who came anywhere near the lines, but the French and English could go ahead as they-felt like.

Admiral Peary: Have you any idea as to how many airplanes there are along that western front on the German side?

Adjt. Prince: There must be about 3000 on that line in actual commission.

Admiral Peary: That means, then, about 10,000 in all, at least?

Adjt. Prince: I should think so; I should say the French have about 2000 and the English possibly 1000, or we have about 2500.

Adjt. Rumsey: If they have 3000 we have 4000; that is, right on the line.

Adjt. Prince: We have about 1000 more than they have, and we are up all the time. The day before I left the front I was called to go out five times, and I went out five times, and spent two hours every time I went out.

It would be gratifying to author and to reader alike if it were possible to give some account of the progress in aerial equipment made by the United States, since its declaration of war. But at the present moment (February, 1918), the government is chary of furnishing information concerning the advance made in the creation of an aerial fleet. Perhaps precise information, if available, would be discouraging to the many who believe that the war will be won in the air. For it is known in a broad general way that the activities of the Administration have been centred upon the construction of training camps and aviation stations. Orders for the actual construction of airplanes have been limited, so that a chorus of criticism arose from manufacturers who declared that they might have to close their works for lack of employment. The apparent check was discouraging to American airmen, and to our Allies who had expected marvellous things from the United States in the way of swift and wholesale preparation for winning battles in the air. The response of the government to all criticism was that it was laying broad foundations in order that construction once begun would proceed with unabated activity, and that when aircraft began to be turned out by the thousands a week there would be aviators and trained mechanics a-plenty to handle them. In this situation the advocates of a special cabinet department of aeronautics found new reason to criticize the Administration and Congress for having ignored or antagonized their appeals. For responsibility for the delay and indifference—if indifference there was—rested equally upon the Secretary of the Navy and the Secretary of War. Each had his measure of control over the enormous sum voted in a lump for aviation, each had the further millions especially voted to his department to account for. But no single individual could be officially asked what had been done with the almost one billion dollars voted for aeronautics in 1917.

But if the authorities seemed to lag, the inventors were busy. Mention has already been made of the new "Liberty" motor, which report had it was the fruit of the imprisonment of two mechanical experts in a hotel room with orders that they should not be freed until they had produced a motor which met all criticisms upon those now in use. Their product is said to have met this test, and the happy result caused a general wish that the Secretaries of War and of the Navy might be similarly incarcerated and only liberated upon producing plans for the immediate creation of an aerial fleet suited to the nation's needs. If, however, the Liberty motor shall prove the complete success which at the moment the government believes it to be, it will be such a spur to the development of the airplane in peace and war, as could not otherwise be applied. For the motor is the true life of the airplane—its heart, lungs, and nerve centre. The few people who still doubt the wide adoption of aircraft for peaceful purposes after the war base their skepticism on the treachery of motors still in use. They repudiate all comparisons with automobiles. They say:

It is perfectly true that a man can run his car repeatedly from New York to Boston without motor trouble. But the trouble is inevitable sooner or later. When it comes to an automobile it is trifling. The driver gets out and makes his repairs by the roadside. But if it comes to the aviator it brings the possibility of death with it every time. If his motor stops he must descend. But to alight he must find a long level field, with at least two hundred yards in which to run off his momentum. If, when he discovers the failure of his motor, he is flying at the height of a mile he must find his landing place within a space of eight miles, for in gliding to earth the ratio of forward movement to height is as eight to one. But how often in rugged and densely populated New England, or Pennsylvania is there a vacant level field half a mile in length? The aviator who made a practice of daily flight between New York and Boston would inevitably meet death in the end.

The criticism is a shrewd and searching one. But it is based on the airplane and the motor of to-day without allowance for the development and improvement which are proceeding apace. It contemplates a craft which has but one motor, but the more modern machines have sufficient lifting power to carry two motors, and can be navigated successfully with one of these out of service. Experiments furthermore are being made with a device after the type of the helicopter which with the steady lightening of the aircraft motor, may be installed on airplanes with a special motor for its operation. This device, it is believed, will enable the airplane so equipped to stop dead in its course with both propellers out of action, to hover over a given spot or to rise or to descend gently in a perpendicular line without the necessity of soaring. It is obvious that if this device prove successful the chief force of the objections to aerial navigation outlined above will be nullified.

The menace of infrequent landing places will quickly remedy itself on busy lines of aerial traffic. The average railroad doing business in a densely populated section has stations once every eight or ten miles which with their sidings, buildings, water tanks, etc., cost far more than the field half a mile long with a few hangars that the fliers will need as a place of refuge. Indeed, although for its size and apparent simplicity of construction an airplane is phenomenally costly, in the grand total of cost an aerial line would cost a tithe of the ordinary railway. It has neither right of way, road bed, rails, nor telegraph system to maintain, and if the average flyer seems to cost amazingly it still foots up less than one fifth the cost of a modern locomotive though its period of service is much shorter.

Just at the present time aircraft costs are high, based on artificial conditions in the market. Their construction is a new industry; its processes not yet standardized; its materials still experimental in many ways and not yet systematically produced. A light sporting monoplane which superficially seems to have about $250 worth of materials in it—exclusive of the engine—will cost about $3000. A fighting biplane will touch $10,000. Yet the latter seems to the lay observer to contain no costly materials to justify so great a charge. The wings are a light wooden framework, usually of spruce, across which a fine grade of linen cloth is stretched. The materials are simple enough, but every bit of wood, every screw, every strand of wire is selected with the utmost care, and the workmanship of their assemblage is as painstaking as the setting of the most precious stones.



"REMEMBER THE LEAST NEGLIGENCE MAY COST A LIFE!" is a sign frequently seen hanging over the work benches in an airplane factory.

When stretched over the framework, the cloth of the wings is treated to a dressing down of a preparation of collodion, which in the jargon of the shop is called "dope." This substance has a peculiar effect upon the cloth, causing it to shrink, and thus making it more taut and rigid than it could be by the most careful stretching. Though the layman would not suspect it, this wash alone costs about $150 a machine. The seaplanes too—or hydroaeroplanes as purists call them—present a curious illustration of unexpected and, it would seem, unexplainable expense. Where the flyer over land has two bicycle wheels on which to land, the flyer over the sea has two flat-bottomed boats or pontoons. These cost from $1000 to $1200 and look as though they should cost not over $100. But the necessity of combining maximum strength with minimum weight sends the price soaring as the machine itself soars. Moreover there is not yet the demand for either air-or seaplanes that would result in the division of labour, standardization of parts, and other manufacturing economies which reduce the cost of products.

To the high cost of aircraft their comparative fragility is added as a reason for their unfitness for commercial uses. The engines cost from $2000 to $5000 each, are very delicate and usually must be taken out of the plane and overhauled after about 100 hours of active service. The strain on them is prodigious for it is estimated that the number of revolutions of an airplane's engine during an hour's flight is equal to the number of revolutions of an automobile's wheels during active service of a whole month.

It is believed that the superior lightness and durability of the Liberty motor will obviate some of these objections to the commercial availability of aircraft in times of peace. And it is certain that with the cessation of the war, the retirement of the governments of the world from the purchasing field and the reduction of the demand for aircraft to such as are needed for pleasure and industrial uses the prices which we have cited will be cut in half. In such event what will be the future of aircraft; what their part in the social and industrial organization of the world?

Ten or a dozen years ago Rudyard Kipling entertained the English reading public of the world with a vivacious sketch of aerial navigation in the year 2000 A.D. He used the license of a poet in avoiding too precise descriptions of what is to come—dealing rather with broad and picturesque generalizations. Now the year 2000 is still far enough away for pretty much anything to be invented, and to become commonplace before that era arrives. Airships of the sort Mr. Kipling pictured may by that period have come and gone—have been relegated to the museums along with the stage-coaches of yesterday and the locomotives of to-day. For that matter before that millennial period shall arrive men may have learned to dispense with material transportation altogether, and be able to project their consciousness or even their astral bodies to any desired point on psychic waves. If a poet is going to prophecy he might as well be audacious and even revolutionary in his predictions.

Mr. Kipling tried so hard to be reasonable that he made himself recognizably wrong so far as the present tendency of aircraft development would indicate. With the Night Mail, is the story of a trip by night across the Atlantic from England to America. It is made in a monster dirigible—though the present tendency is to reject the dirigible for the swifter, less costly, and more airworthy (leave "seaworthy" to the plodding ships on old ocean's breast) airplanes. If, however, we condone this glaring improbability we find Mr. Kipling's tale full of action and imaginary incident that give it an air of truth. His ship is not docked on the ground at the tempest's mercy, but is moored high in air to the top of a tall tower up which passengers and freight are conveyed in elevators. His lighthouses send their beams straight up into the sky instead of projecting them horizontally as do those which now guard our coasts. Just why lighthouses are needed, however, he does not explain. There are no reefs on which a packet of the air may run, no lee shores which they must avoid. On overland voyages guiding lights by night may be useful, as great white direction strips laid out on the ground are even now suggested as guides for daylight flying. But the main reliance of the airman must be his compass. Crossing the broad oceans no lighted path is possible, and even in a voyage from New York to Chicago, or from London to Rome good airmanship will dictate flight at a height that will make reliance upon natural objects as a guide perilous. The airman has the advantage over the sailor in that he may lay his course on leaving his port, or flying field, and pursue it straight as an arrow to his destination. No rocks or other obstacles bar his path, no tortuous channels must be navigated. All that can divert him from his chosen course is a steady wind on the beam, and that is instantly detected by his instruments and allowance made for it. On the other hand the sailor has a certain advantage over the airman in that his more leisurely progress allows time for the rectification of errors in course arising from contrary currents or winds. An error of a point, or even two, amounts to but little in a day's steaming of perhaps four hundred miles. It can readily be remedied, unless the ship is too near shore. But when the whole three thousand miles of Atlantic are covered in twenty hours in the air, the course must be right from the start and exactly adhered to, else the passenger for New York may be set down in Florida.

It is not improbable that even before the war is over the crossing of the Atlantic by plane will be accomplished. Certainly it will be one of the first tasks undertaken by airmen on the return of peace. But it is probable that the adaptation of aircraft to commercial uses will be begun with undertakings of smaller proportions. Already the United States maintains an aerial mail route in Alaska, while Italy has military mail routes served by airplanes in the Alps. These have been undertaken because of the physical obstacles to travel on the surface, presented in those rugged neighbourhoods. But in the more densely populated regions of the United States considerations of financial profit will almost certainly result in the early establishment of mail and passenger air service. Air service will cut down the time between any two given points at least one half, and ultimately two thirds. Letters could be sent from New York to Boston, or even to Buffalo, and an answer received the same day. The carrying plane could take on each trip five tons of mail. Philadelphia would be brought within forty-five minutes of New York; Washington within two hours instead of the present five. Is there any doubt of the creation of an aerial passenger service under such conditions? Already a Caproni triplane will carry thirty-five passengers beside guns—say, fifty passengers if all other load be excluded, and has flown with a lighter load from Newport News to New York. It is easily imaginable that by 1920 the airplane capable of carrying eighty persons—or the normal number now accommodated on an inter-urban trolley car—will be an accomplished fact.

The lines that will thus spring up will need no rails, no right of way, no expensive power plant. Their physical property will be confined to the airplanes themselves and to the fields from which the craft rise and on which they alight, with the necessary hangars. These indeed will involve heavy expenditure. For a busy line, with frequent sailings, of high speed machines a field will need to be in the neighbourhood of a mile square. A plane swooping down for its landing is not to be held up at the switch like a train while room is made for it. It is an imperative guest, and cannot be gainsaid. Accordingly the fields must be large enough to accommodate scores of planes at once and give each new arrival a long straight course on which to run off its momentum. It is obvious therefore that the union stations for aircraft routes cannot be in the hearts of our cities as are the railroad stations of to-day, but must be fairly well out in the suburbs.

A form of machine which the professional airmen say has yet to be developed is the small monoplane, carrying two passengers at most, and of low speed—not more than twenty miles an hour at most. In this age of speed mania the idea of deliberately planning a conveyance or vehicle that shall not exceed a low limit seems out of accord with public desire. But the low speed airplane has the advantage of needing no extended field in which to alight. It reaches the ground with but little momentum to be taken up and can be brought up standing on the roof of a house or the deck of a ship. Small machines of this sort are likely to serve as the runabouts of the air, to succeed the trim little automobile roadsters as pleasure craft.



The beginning of the fourth year of the war brought a notable change in aerial tactics. For three years everything had been sacrificed to speed. Such aerial duels as have been described were encouraged by the fact that aircraft were reduced to the proportions needful for carrying one man and a machine gun. The gallant flyers went up in the air and killed each other. That was about all there was to it. While as scouts, range finders, guides for the artillery, they exerted some influence on the course of the war, as a fighting arm in its earlier years, they were without efficiency. The bombing forays were harassing but little more, because the craft engaged were of too small capacity to carry enough bombs to work really serious damage, while the ever increasing range of the "Archies" compels the airmen to deliver their fire from so great a height as to make accurate aim impossible.



But Kiel, Wilhelmshaven and Zeebrugge are likely to change all this. The constant contemplation of those nests for the sanctuary of pestiferous submarines, effectively guarded against attack by either land or water, has stirred up the determination of the Allies to seek their destruction from above. Heavy bombing planes are being built in all the Allied workshops for this purpose, and furthermore to give effect to the British determination to take vengeance upon Germany, for her raids upon London. It is reported that the United States, by agreement with its Allies, is to specialize in building the light, swift scout planes, but in other shops the heavy triplane, the dreadnought of the air is expected to be the feature of 1918. With it will come an entirely novel strategic use of aircraft in war, and with it too, which is perhaps the more permanently important, will come the development of aircraft of the sort that will be readily adaptable to the purposes of peace when the war shall end.



THE SUBMARINE BOAT



CHAPTER XI

BEGINNINGS OF SUBMARINE INVENTION

In September, 1914 the British Fleet in the North Sea had settled down to the monotonous task of holding the coasts of Germany and the channels leading to them in a state of blockade. The work was dismal enough. The ships tossing from day to day on the always unquiet waters of the North Sea were crowded with Jackies all of whom prayed each day that the German would come from hiding and give battle. Not far from the Hook of Holland engaged in this monotonous work were three cruisers of about 12,000 tons, each carrying 755 men and officers. They were the Cressy, Aboukir, and Hogue—not vessels of the first rank but still important factors in the British blockade. They were well within the torpedo belt and it may be believed that unceasing vigilance was observed on every ship. Nevertheless without warning the other two suddenly saw the Aboukir overwhelmed by a flash of fire, a pillar of smoke and a great geyser of water that rose from the sea and fell heavily upon her deck. Instantly followed a thundering explosion as the magazines of the doomed ship went off. Within a very few minutes, too little time to use their guns against the enemy had they been able to see him, or to lower their boats, the Aboukir sank leaving the crew floundering in the water.

In the distance lay the German submarine U-9—one of the earliest of her class in service. From her conning tower Captain Weddigen had viewed the tragedy. Now seeing the two sister ships speeding to the rescue he quickly submerged. It may be noted that as a result of what followed, orders were given by the British Admiralty that in the event of the destruction of a ship by a submarine others in the same squadron should not come to the rescue of the victim, but scatter as widely as possible to avoid a like fate. In this instance the Hogue and the Cressy hurried to the spot whence the Aboukir had vanished and began lowering their boats. Hardly had they begun the work of mercy when a torpedo from the now unseen foe struck the Hogue and in twenty minutes she too had vanished. While she was sinking the Cressy, with all guns ready for action and her gunners scanning the sea in every direction for this deadly enemy, suddenly felt the shock of a torpedo and, her magazines having been set off, followed her sister ships to the ocean's bed.

In little more than half an hour thirty-six thousand tons of up-to-date British fighting machinery, and more than 1200 gallant blue jackets had been sent to the depths of the North Sea by a little boat of 450 tons carrying a crew of twenty-six men.

The world stood aghast. With the feeling of horror at the swift death of so many caused by so few, there was mingled a feeling of amazement at the scientific perfection of the submarine, its power, and its deadly work. Men said it was the end of dreadnoughts, battleships, and cruisers, but the history of the war has shown singularly few of these destroyed by submarines since the first novelty of the attack wore off. The world at the moment seemed to think that the submarine was an entirely new idea and invention. But like almost everything else it was merely the ultimate reduction to practical use of an idea that had been germinating in the mind of man from the earliest days of history.

We need not trouble ourselves with the speculations of Alexander the Great, Aristotle, and Pliny concerning "underwater" activities. Their active minds gave consideration to the problem, but mainly as to the employment of divers. Not until the first part of the sixteenth century do we find any very specific reference to actual underwater boats. That appears in a book of travels by Olaus Magnus, Archbishop of Upsala in Sweden. Notwithstanding the gentleman's reverend quality, one must question somewhat the veracity of the chapter which he heads:

"Of the Leather Ships Made of Hides Used by the Pyrats of Greenland."

He professed to have seen two of these "ships," more probably boats, hanging in a cathedral church in Greenland. With these singular vessels, according to his veracious reports the people of that country could navigate under water and attack stranger ships from beneath. "For the Inhabitants of that Countrey are wont to get small profits by the spoils of others," he wrote, "by these and the like treacherous Arts, who by their thieving wit, and by boring a hole privately in the sides of the ships beneath (as I said) have let in the water and presently caused them to sink."

Leaving the tale of the Archbishop where we think it must belong in the realm of fiction, we may note that it was not until the beginning of the seventeenth century that the first submarine boat was actually built and navigated. A Hollander, Cornelius Drebel, or Van Drebel, born in 1572, in the town of Alkmaar, had come to London during the reign of James I., who became his patron and friend. Drebel seems to have been a serious student of science and in many ways far ahead of his times. Moreover, he had the talent of getting next to royalty. In 1620 he first conceived the idea of building a submarine. Fairly detailed descriptions of his boats—he built three from 1620-1624—and of their actual use, have been handed down to us by men whose accuracy and truthfulness cannot be doubted. The Honorable Robert Boyle, a scientist of unquestioned seriousness, tells in his New Experiments, Physico-Mechanical touching the Spring of the Air and its Effects about Drebel's work in the quaint language of his time:

But yet on occasion of this opinion of Paracelsus, perhaps it will not be impertinent if, before I proceed, I acquaint your Lordship with a conceit of that deservedly famous mechanician and Chymist, Cornelius Drebel, who, among other strange things that he perform'd, is affirm'd, by more than a few credible persons, to have contrived for the late learned King James, a vessel to go under water; of which, trial was made in the Thames, with admired success, the vessel carrying twelve rowers, besides passengers; one which is yet alive, and related it to an excellent Mathematician that informed me of it. Now that for which I mention this story is, that having had the curiosity and opportunity to make particular inquiries among the relations of Drebel, and especially of an ingenious physician that married his daughter, concerning the grounds upon which he conceived it feasible to make men unaccustomed to continue so long under water without suffocation, or (as the lately mentioned person that went in the vessel affirms) without inconvenience; I was answered, that Drebel conceived, that it is not the whole body of the air, but a certain quintessence (as Chymists speak) or spirituous part of it, that makes it fit for respiration; which being spent, the remaining grosser body, or carcase, if I may so call it, of the air, is unable to cherish the vital flame residing in the heart; so that, for aught I could gather, besides the mechanical contrivances of his vessel, he had a chymical liquor, which he accounted the chief secret of his submarine navigation. For when, from time to time, he conceived that the finer and purer part of the air was consumed, or over-clogged by the respiration and steam of those that went in his ship, he would by unstopping a vessel full of this liquor, speedily restore to the troubled air such a proportion of vital parts, as would make it again, for a good while, fit for respiration whether by dissipating, or precipitating the grosser exhalations, or by some other intelligible way, I must not now stay to examine, contenting myself to add, that having had the opportunity to do some service to those of his relations that were most intimate with him, and having made it my business to learn what this strange liquor might be, they constantly affirmed that Drebel would never disclose the liquor unto any, nor so much as tell the nature whereof he had made it, to above one person, who himself assured me what it was.

This most curious narrative suggests that in some way Drebel, who died in London in 1634, had discovered the art of compressing oxygen and conceived the idea of making it serviceable for freshening the air in a boat, or other place, contaminated by the respiration of a number of men for a long time. Indeed the reference made to the substance by which Drebel purified the atmosphere in his submarine as "a liquor" suggests that he may possibly have hit upon the secret of liquid air which late in the nineteenth century caused such a stir in the United States. Of his possession of some such secret there can be no doubt whatsoever, for Samuel Pepys refers in his famous diary to a lawsuit, brought in the King's Courts by the heirs of Drebel, to secure the secret for their own use. What was the outcome of the suit or the subsequent history of Drebel's invention history does not record.

Throughout the next 150 years a large number of inventors and near-inventors occupied themselves with the problem of the submarine. Some of these men went no further than to draw plans and to write out descriptions of what appeared to them to be feasible submarine boats. Others took one step further, by taking out patents, but only very few of the submarine engineers of this period had either the means or the courage to test their inventions in the only practicable way, by building an experimental boat and using it.

In spite of this apparent lack of faith on the part of the men who worked on the submarine problem, it would not be fair to condemn them as fakirs. Experimental workers, in those times, had to face many difficulties which were removed in later times. The study of science and the examination of the forces of nature were not only not as popular as they became later, but frequently were looked upon as blasphemous, savouring of sorcery, or as a sign of an unbalanced mind.



England and France supplied most of the men who occupied themselves with the submarine problem between 1610 and 1760. Of the Englishmen, the following left records of one kind or another concerning their labours in this direction. Richard Norwood, in 1632, was granted a patent for a contrivance which was apparently little more than a diving apparatus. In 1648, Bishop Wilkins published a book, Mathematical Magick, which was full of rather grotesque projects and which contained one chapter on the possibility "of framing an ark for submarine navigation." In 1691, patents were granted on engines connected with submarine navigation to John Holland—curious forerunner of a name destined to be famous two hundred years later—and on a submarine boat to Sir Stephen Evance.

In Prance, two priests, Fathers Mersenne and Fournier, published in 1634 a small book called Questions Theologiques, Physiques, Morales et Mathematiques, which contained a detailed description of a submarine boat. They suggested that the hull of submarines ought to be of metal and not of wood, and that their shape ought to be as nearly fishlike as possible. Nearly three hundred years have hardly altered these opinions. Ancient French records also tell us that six years later, in 1640, the King of France had granted a patent to Jean Barrie, permitting him during the next twelve years to fish at the bottom of the sea with his boat. Unluckily Barrie's fish stories have expired with his permit. In 1654, a French engineer, De Son, is said to have built at Rotterdam a submarine boat. Little is known concerning this vessel except that it was reported to have been seventy-two feet long, twelve feet high, and eight feet broad, and to have been propelled by a paddlewheel instead of oars.

Borelli, about whom very little seems to be known, is credited with having invented in 1680 a submarine boat, whose descent and ascent were regulated by a series of leather bottles placed in the hull of the boat with their mouths open to the surrounding water. The English magazine, Graphic, published a picture which is considered the oldest known illustration of any submarine boat. This picture matches in all details the description of Borelli's boat, but it is credited to a man called Symons.

Twenty-seven years later, in 1774, another Englishman, J. Day, built a small submarine boat, and after fairly extensive experiments, descended in his boat in Plymouth harbour. This descent is of special interest because we have a more detailed record of it than of any previous submarine exploit, and because Day is the first submarine inventor who lost his life in the attempt to prove the feasibility of his invention. The Annual Register of 1774 gives a narration in detail of Day's experiments and death and inasmuch as this is the first ungarbled report of a submarine descent, it may be quoted at length.

Authentic account of a late unfortunate transaction, with respect to a diving machine at Plymouth.

Mr. Day (the sole projector of the scheme, and, as matters have turned out, the unhappy sacrifice to his own ingenuity) employed his thoughts for some years past in planning a method of sinking a vessel under water, with a man in it, who should live therein for a certain time, and then by his own means only, bring himself up to the surface. After much study he conceived that his plan could be reduced into practice. He communicated his idea in the part of the country where he lived, and had the most sanguine hopes of success. He went so far as to try his project in the Broads near Yarmouth. He fitted a Norwich market-boat for his purpose, sunk himself thirty feet under water, where he continued during the space of twenty-four hours, and executed his design to his own entire satisfaction. Elated with this success, he then wanted to avail himself of his invention. He conversed with his friends, convinced them that he had brought his undertaking to a certainty; but how to reap the advantage of it was the difficulty that remained. The person in whom he confided suggested to him, that, if he acquainted the sporting Gentlemen with the discovery, and the certainty of the performance, considerable betts would take place, as soon as the project would be mentioned in company. The Sporting Kalendar was immediately looked into, and the name of Blake soon occurred; that gentleman was fixed upon as the person to whom Mr. Day ought to address himself. Accordingly, Mr. Blake, in the month of November last, received the following letter:

"SIR,

"I found out an affair by which many thousands may be won; it is of a paradoxical nature, but can be performed with ease; therefore, sir, if you chuse to be informed of it, and give me one hundred pounds of every thousand you shall win by it, I will very readily wait upon you and inform you of it. I am myself but a poor mechanic and not able to make anything by it without your assistance.

"Your's, etc.

"J. DAY."

Mr. Blake had no conception of Mr. Day's design, nor was he sure that the letter was serious. To clear the matter up, he returned for answer, that, if Mr. Day would come to town, and explain himself, Mr. Blake would consider of the proposal. If he approved of it, Mr. Day should have the recompence he desired; if, on the other hand, the plan should be rejected, Mr. Blake would make him a present to defray the expences of his journey. In a short time after Mr. Day came to town; Mr. Blake saw him and desired to know what secret he was possessed of. The man replied, "that he could sink a ship 100 feet deep in the sea with himself in it, and remain therein for the space of 24 hours, without communication with anything above; and at the expiration of the time, rise up again in the vessel." The proposal, in all its parts, was new to Mr. Blake. He took down the particulars, and, after considering the matter, desired some kind of proof of the practicability. The man added that if Mr. Blake would furnish him with the materials necessary, he would give him an occular demonstration. A model of the vessel, with which he was to perform the experiment, was then required, and in three or four weeks accomplished, so as to give a perfect idea of the principle upon which the scheme was to be executed, and, in time, a very plausible promise of success, not to Mr. Blake only, but many other gentlemen who were consulted upon the occasion. The consequence was, that Mr. Blake, agreeably to the man's desire, advanced money for the construction of a vessel fit for that purpose. Mr. Day, thus assisted, went to Plymouth with his model, and set a man in that place to work upon it. The pressure of the water at 100 feet deep was a circumstance of which Mr. Blake was advised, and touching that article he gave the strongest precautions to Mr. Day, telling him, at any expence, to fortify the chamber in which he was to subsist, against the weight of such a body of water. Mr. Day set off in great spirits for Plymouth, and seemed so confident, that Mr. Blake made a bett that the project would succeed, reducing, however, the depth of water from 100 yards to 100 feet, and the time from 24 to 12 hours. By the terms of the wager, the experiment was to be made within three months from the date; but so much time was necessary for due preparation, that on the appointed day things were not in readiness and Mr. Blake lost the bett.



In some short time afterwards the vessel was finished, and Mr. Day still continued eager for the carrying of his plan into execution; he was uneasy at the idea of dropping the scheme and wished for an opportunity to convince Mr. Blake that he could perform what he had undertaken. He wrote from Plymouth that everything was in readiness and should be executed the moment Mr. Blake arrived. Induced by this promise, Mr. Blake set out for Plymouth; upon his arrival a trial was made in Cat-water, where Mr. Day lay, during the flow of tide, six hours, and six more during the tide of ebb; confined all the time in the room appropriated for his use. A day for the final determination was fixed; the vessel was towed to the place agreed upon; Mr. Day provided himself with whatever he thought necessary; he went into the vessel, let the water into her and with great composure retired to the room constructed for him, and shut up the valve. The ship went gradually down in 22 fathoms of water at 2 o'clock on Tuesday, June 28, in the afternoon, being to return at 2 the next morning. He had three buoys or messengers, which he could send to the surface at option, to announce his situation below; but, none appearing, Mr. Blake, who was near at hand in a barge, began to entertain some suspicion. He kept a strict lookout, and at the time appointed, neither the buoys nor the vessel coming up, he applied to the Orpheus frigate, which lay just off the barge, for assistance. The captain with the most ready benevolence supplied them with everything in his power to seek for the ship. Mr. Blake, in this alarming situation was not content with the help of the Orpheus only; he made immediate application to Lord Sandwich (who happened to be at Plymouth) for further relief. His Lordship with great humanity ordered a number of hands from the dock-yard, who went with the utmost alacrity and tried every effort to regain the ship, but unhappily without effect.

Thus ended this unfortunate affair. Mr. Blake had not experience enough to judge of all possible contingencies, and he had now only to lament the credulity with which he listened to a projector, fond of his own scheme but certainly not possessed of skill enough to guard against the variety of accidents to which he was liable. The poor man has unfortunately shortened his days; he was not however tempted or influenced by anybody; he confided in his own judgment, and put his life to the hazard upon his own mistaken notions.

Many and various have been the opinions on this strange, useless, and fatal experiment, though the more reasonable part of mankind seemed to give it up as wholly impracticable. It is well-known, that pent-up air, when overcharged with the vapours emitted out of animal bodies, becomes unfit for respiration; for which reason, those confined in the diving-bell, after continuing some time under water are obliged to come up, and take in fresh air, or by some such means recruit it. That any man should be able after having sunk a vessel to so great a depth, to make that vessel at pressure, so much more specifically lighter than water, as thereby to enable it to force its way to the surface, through the depressure of so great a weight, is a matter not hastily to be credited. Even cork, when sunk to a certain depth will, by the great weight of the fluid upon it, be prevented from rising.

The English of the Annual Register leaves much to be desired in clarity. It makes reasonably clear, however, that the unfortunate Mr. Day's knowledge of submarine conditions was, by no means, equal to Mr. Blake's sporting spirit. Even to-day one hundred feet is an unusual depth of submersion for the largest submarines.

The credit for using a submarine boat for the first time in actual warfare belongs to a Yankee, David Bushnell. He was born in Saybrook, Connecticut, and graduated from Yale with the class of 1775. While still in college he was interested in science and as far as his means and opportunities allowed, he devoted a great deal of his time and energy to experimental work. The problem which attracted his special attention was how to explode powder under water, and before very long he succeeded in solving this to his own satisfaction as well as to that of a number of prominent people amongst whom were the Governor of Connecticut and his Council. Bushnell's experiments, of course, fell in the period during which the Revolutionary War was fought, and when he had completed his invention, there naturally presented itself to him a further problem. How could his device be used for the benefit of his country and against the British ships which were then threatening New York City? As a means to this end, Bushnell planned and built a submarine boat which on account of its shape is usually called the Turtle.

General Washington thought very highly of Bushnell, whom he called in a letter to Thomas Jefferson "a man of great mechanical powers, fertile in inventions and master of execution." In regard to Bushnell's submarine boat the same letter, written after its failure, says: "I thought and still think that it was an effort of genius, but that too many things were necessary to be combined to expect much against an enemy who are always on guard."

During the whole period of the building of the Turtle Bushnell was in ill health. Otherwise he would have navigated it on its trial trip himself for he was a man of undoubted courage and wrapped up alike in the merits of his invention and in the possibility of utilizing it to free New York from the constant ignominy of the presence of British ships in its harbour. But his health made this out of the question. Accordingly he taught his brother the method of navigating the craft, but at the moment for action the brother too fell ill. It became necessary to hire an operator. This was by no means easy as volunteers to go below the water in a submarine boat of a type hitherto undreamed of, and to attach an explosive to the hull of a British man-of-war, the sentries upon which were presumably especially vigilant, being in a hostile harbour, was an adventure likely to attract only the most daring and reckless spirits. In a letter to Thomas Jefferson, other portions of which we shall have occasion to quote later, Bushnell refers to this difficulty in finding a suitable operator and tells briefly and with evident chagrin the story of the failure of the attempts made to utilize successfully his submarine:



After various attempts to find an operator to my wish, I sent one who appeared more expert than the rest from New York to a 50-gun ship lying not far from Governor's Island. He went under the ship and attempted to fix the wooden screw into her bottom, but struck, as he supposes, a bar of iron which passes from the rudder hinge, and is spiked under the ship's quarter. Had he moved a few inches, which he might have done without rowing, I have no doubt but he would have found wood where he might have fixed the screw, or if the ship were sheathed with copper he might easily have pierced it; but, not being well skilled in the management of the vessel, in attempting to move to another place he lost the ship. After seeking her in vain for some time, he rowed some distance and rose to the surface of the water, but found daylight had advanced so far that he durst not renew the attempt. He says that he could easily have fastened the magazine under the stem of the ship above water, as he rowed up to the stern and touched it before he descended. Had he fastened it there the explosion of 150 lbs. of powder (the quantity contained in the magazine) must have been fatal to the ship. In his return from the ship to New York he passed near Governor's Island, and thought he was discovered by the enemy on the island. Being in haste to avoid the danger he feared, he cast off the magazine, as he imagined it retarded him in the swell, which was very considerable. After the magazine had been cast off one hour, the time the internal apparatus was set to run, it blew up with great violence.

Afterwards there were two attempts made in Hudson's River, above the city, but they effected nothing. One of them was by the aforementioned person. In going towards the ship he lost sight of her, and went a great distance beyond her. When he at length found her the tide ran so strong that, as he descended under water for the ship's bottom, it swept him away. Soon after this the enemy went up the river and pursued the boat which had the submarine vessel on board and sunk it with their shot. Though I afterwards recovered the vessel, I found it impossible at that time to prosecute the design any farther.

The operator to whom Bushnell had entrusted his submarine boat was a typical Yankee, Ezra Lee of Lyme, Connecticut. His story of the adventure differs but little from that of Bushnell, but it is told with a calm indifference to danger and a seeming lack of any notion of the extraordinary in what he had done that gives an idea of the man. "When I rode under the stern of the ship [the Eagle] I could see the men on deck and hear them talk," he wrote. "I then shut down all the doors, sunk down, and came up under the bottom of the ship."

This means that he hermetically sealed himself inside of a craft, shaped like two upper turtle shells joined together—hence the name of the Turtle. He had entered through the orifice at the top, whence the head of the turtle usually protrudes. This before sinking he had covered and made water-tight by screwing down upon it a brass crown or top like that to a flask. Within he had enough air to support him thirty minutes. The vessel stood upright, not flat as a turtle carries himself. It was maintained in this position by lead ballast. Within the operator occupied an upright position, half sitting, half standing. To sink water was admitted, which gathered in the lower part of the boat, while to rise again this was expelled by a force pump. There were ventilators and portholes for the admission of light and air when operating on the surface, but once the cap was screwed down the operator was in darkness.

In this craft, which suggests more than anything else a curiously shaped submarine coffin, Lee drifted along by the side of the ship, navigating with difficulty with his single oar and seeking vainly to find some spot to which he might affix his magazine. A fact which might have disquieted a more nervous man was that the clockwork of this machine was running and had been set to go off in an hour from the time the voyage was undertaken. As to almost anyone in that position minutes would seem hours, the calmness of sailor Lee's nerves seems to be something beyond the ordinary.

When he finally abandoned the attempt on the Eagle he started up the bay. Off Governor's Island he narrowly escaped capture.

When I was abreast of the Fort on the Island three hundred or four hundred men got upon the parapet to observe me; at length a number came down to the shore, shoved off a twelve oar'd barge with five or six sitters and pulled for me. I eyed them, and when they had got within fifty or sixty yards of me I let loose the magazine in hopes that if they should take me they would likewise pick up the magazine and then we should all be blown up together. But as kind providence would have it they took fright and returned to the Island to my infinite joy.... The magazine after getting a little past the Island went off with a tremendous explosion, throwing up large bodies of water to an immense height.

During the last quarter of the eighteenth and during the first half of the nineteenth century France was the chief centre for the activities of submarine inventors. However, very few of the many plans put forward in this period were executed. The few exceptions resulted in little else than trial boats which usually did not live up to the expectations of their inventors or their financial backers and were, therefore, discarded in quick order. In spite of this lack of actual results this particular period was of considerable importance to the later development of the submarine. Almost every one of the many boats then projected or built contained some innovation and in this way some of the many obstacles were gradually overcome. Strictly speaking the net result of the experimental work done during these seventy-five years by a score or more of men, most of whom were French, though a few were English, was the creation of a more sane and sound basis on which, before long, other men began to build with greater success.

The one notable accomplishment of interest, especially to Americans, was the submarine built in 1800-01 by Robert Fulton. Fulton, of course, is far better known by his work in connection with the discovery and development of steam navigation. Born in Pennsylvania in 1765, he early showed marked mechanical genius. In 1787 he went to England with the purpose of studying art under the famous painter West, but soon began to devote most of his time and energy to mechanical problems. Not finding in England as much encouragement as he had hoped, he went, in 1797, to Paris and, for the next seven years, lived there in the house of the American Minister, Joel Barlow.

As soon as he had settled down in France, he offered his plans of a submarine boat which he called the Nautilus to the French Government. Though a special commission reported favourably on this boat, the opposition of the French Minister of the Marine was too strong to be overcome, even after another commission had approved a model built by Fulton. In 1800, however, he was successful in gaining the moral and financial support of Napoleon Bonaparte, then First Consul of the French Republic.

Fulton immediately proceeded to build the Nautilus and completed the boat in May, 1801. It was cigar-shaped, about seven feet in diameter and over twenty-one feet in length. The hull was of copper strengthened by iron ribs. The most noticeable features were a collapsible mast and sail and a small conning tower at the forward end. The boat was propelled by a wheel affixed to the centre of the stern and worked by a hand-winch. A rudder was used for steering, and increased stability was gained by a keel which ran the whole length of the hull.



Soon after completion the boat was taken out for a number of trial trips all of which were carried out with signal success and finally culminated, on June 26, 1801, in the successful blowing up of an old ship furnished by the French Government. Although the Nautilus created a great sensation, popular as well as official interest began soon to flag. Fulton received no further encouragement and finally gave up his submarine experiments.



In 1806 he returned to America. By 1814 he had built another submarine boat which he called the Mute. It was, comparatively speaking, of immense size, being over eighty feet long, twenty-one feet wide, and fourteen feet deep and accommodating a hundred men. It was iron-plated on top and derived its peculiar name from the fact that it was propelled by a noiseless engine. Before its trials could be completed, Fulton died on February 24, 1815, and no one seemed to have sufficient interest or faith in his new boat to continue his work.

In the middle of the nineteenth century for the first time a German became seriously interested in submarines. His name was Wilhelm Bauer. He was born in 1822 in a small town in Bavaria and, though a turner by trade, joined the army in 1842. Bauer was even in his youth of a highly inventive turn of mind. He possessed an indomitable will and an unlimited supply of enthusiasm. Step by step he acquired, in what little time he could spare from his military duties, the necessary mechanical knowledge, and finally, supported financially by a few loyal friends and patrons, he built his first submarine at Kiel at a cost of about $2750. It sank to the bottom on its first trial trip, fortunately without anyone on board. Undaunted he continued his efforts.

When he found that his support at Kiel was weakening, he promptly went to Austria. In spite of glowing promises, opposition on the part of some officials deprived Bauer of the promised assistance. He went then to England and succeeded in enlisting the interest of the Prince Consort. A boat was built according to Bauer's plans, which, however, he was forced by the interference of politicians to change to such an extent that it sank on its first trial with considerable loss of life.

Still full of faith in his ability to produce a successful submarine, Bauer now went to Russia. In 1855, he built a boat at St. Petersburg and had it accepted by the Russian Government. It was called Le Diable Marin and looked very much like a dolphin. Its length was fifty-two feet, its beam twelve feet five inches, and its depth eleven feet. Its hull was of iron. A propeller, worked by four wheels, furnished motive power. Submersion and stability were regulated by four cylinders into which water could be pumped at will.

The first trial of the boat was made on May 26, 1856, and was entirely successful. In later trials as many as fourteen men at a time descended in Le Diable Marin. It is said that Bauer made a total of 134 trips on his boat. All but two were carried out successfully. At one time, however, the propeller was caught in some seaweed and it was only by the quickest action that all the water was pumped out and the bow of the boat allowed to rise out of the water, so that the occupants managed to escape by means of the hatchway. Like Fulton in France, Bauer now experienced in Russia a sudden decrease of official interest. When he finally lost his boat, about four weeks later, he also lost his courage, and in 1858 he returned to Germany where he later died in comparative poverty.

Contemporary with Bauer's submarines and immediately following them were a large number of other boats. Some of these were little more than freaks. Others failed in certain respects but added new features to the sum-total of submarine inventions. As early as 1854, M. Marie-Davy, Professor of Chemistry at Montpellier University, suggested an electro-magnetic engine as motive power. In 1855 a well-known engineer, J. Nasmith, suggested a submerged motor, driven by a steam engine. None of the boats of this period proved successful enough, however, to receive more than passing notice, and very few, indeed, ever reached the trial stage. But before long the rapid development of internal-combustion engines and the immense progress made in the study of electricity was to advance the development of submarines by leaps and bounds.



CHAPTER XII

THE COMING OF STEAM AND ELECTRICITY

In the fall of 1863, the Federal fleet was blockading the harbour of Charleston, S. C. Included among the many ships was one of the marvels of that period, the United States battleship Ironsides. Armour-plated and possessing what was then considered a wonderful equipment of high calibred guns and a remarkably trained crew, she was the terror of the Confederates. None of their ships could hope to compete with her and the land batteries of the Southern harbour were powerless to reach her.



During the night of October 5, 1863, the officer of the watch on board the Ironsides, Ensign Howard, suddenly observed a small object looking somewhat like a pleasure boat, floating close to his own ship. Before Ensign Howard's order to fire at it could be executed, the Ironsides was shaken from bow to stern, an immense column of water was thrown up and flooded her deck and engine room, and Ensign Howard fell, mortally wounded. The little floating object was responsible for all this. It was a Confederate submersible boat, only fifty feet long and nine feet in diameter, carrying a fifteen-foot spar-torpedo. She had been named David and the Confederate authorities hoped to do away by means of her with the Goliaths of the Federal navy. Manned only by five men, under the command of Lieutenant W. T. Glassel, driven by a small engine and propeller, she had managed to come up unobserved within striking distance of the big battleship.

The attack, however, was unsuccessful. The Ironsides was undamaged. On the other hand the plucky little David had been disabled to such an extent that her crew had to abandon her and take to the water, allowing their boat to drift without motive power. Four of them were later picked up. According to an account in Barnes, Torpedoes and Torpedo Warfare, the engineer, after having been in the water for some time, found himself near her and succeeded in getting on board. He relighted her fires and navigated his little boat safely back to Charleston. There she remained, making occasional unsuccessful sallies against the Federal fleet, and when Charleston was finally occupied by the Federal forces, she was found there.

In spite of this failure the Confederates continued their attempts to break the blockade of their most important port by submarine devices. A new and somewhat improved David was ordered and built at another port. News of this somehow reached the Federal Navy Department and was immediately communicated to Vice-Admiral Dahlgren, in command of the blockading fleet. Despite this warning and instructions to all the officers of the fleet, the second David succeeded in crossing Charleston bar.

This new boat was a real diving submarine boat and though frequently called David had been christened the Hundley. It had been built in the shipyards of McClintock & Hundley at Mobile, Alabama, and had been brought to Charleston by rail. On her trial she proved very clumsy and difficult to manage. For her first trip a crew of nine men volunteered. Not having any conning tower it was necessary that one of the hatchways should be left open while the boat travelled on the surface so that the steersman could find his bearings. While she was on her first trip, the swell from a passing boat engulfed her. Before the hatchway could be closed, she filled with water. Of course, she sank like a piece of lead and her entire crew, with the exception of the steersman, was drowned.

In spite of this mishap the Hundley was raised and again put in commission. Lieutenant Payne who had steered her on her first fatal trip had lost neither his courage nor faith and again assumed command of her. Soon after she started on her second trip a sudden squall arose. Before the hatchways could be closed, she again filled with water and sank, drowning all of her crew with the exception of Lieutenant Payne and two of his men.

Undaunted he took her out on a third trip after she had again been raised. Ill luck still pursued her. Off Fort Sumter she was capsized and this time four of her crew were drowned.

The difficulties encountered in sailing the Hundley on the surface of the water apparently made no difference when it came to finding new crews for her. By this time, however, the powers that be had become anxious that their submarine boat should accomplish something against an enemy, instead of drowning only her own men and it was decided to use her on the next trip in a submerged state. Again Lieutenant Payne was entrusted with her guidance. Her hatches were closed, her water tanks filled, and she was off for her first dive. Something went wrong however; either too much water had been put in her tanks or else the steering gear refused to work. At any rate she hit the muddy bottom with such force that her nose became deeply imbedded and before she could work herself free her entire crew of eight was suffocated. Lieutenant Payne himself lost his life which he had risked so valiantly and frequently before.

Once more she was raised and once more volunteers rushed to man her. On the fifth trip, however, the Hundley, while travelling underwater, became entangled in the anchor chains of a boat she passed and was held fast so long that her crew of nine were dead when she was finally disentangled and raised.

Thirty-five lives had so far been lost without any actual results having been accomplished. In spite of this a new crew was found. Her commander, Lieutenant Dixon, was ordered to make an attack against the Federal fleet immediately, using, however, the boat as a submersible instead of a submarine.

Admiral David Porter in his Naval History of the Civil War described the attack, which was directed against the U. S. S. Housatonic, one of the newest Federal battleships, as follows:

At about 8.45 P. M., the officer of the deck on board the unfortunate vessel discovered something about one hundred yards away, moving along the water. It came directly towards the ship, and within two minutes of the time it was first sighted was alongside. The cable was slipped, the engines backed, and all hands called to quarters. But it was too late—the torpedo struck the Housatonic just forward of the mainmast, on the starboard side, on a line with the magazine. The man who steered her (the Hundley) knew where the vital spots of the steamer were and he did his work well. When the explosion took place the ship trembled all over as if by the shock of an earthquake, and seemed to be lifted out of the water, and then sank stern foremost, heeling to port as she went down.

Only a part of the Housatonic's complement was saved. Of the Hundley no trace was discovered and she was believed to have escaped. Three years later, however, divers who had been sent down to examine the hull of the Housatonic found the little submarine stuck in the hole made by her attack on the larger ship and inside of her the bodies of her entire crew.

The submarines and near-submarines built in the United States during the Civil War were remarkable rather for what they actually accomplished than for what they contributed towards the development of submarine boats. Perhaps the greatest service which they rendered in the latter direction was that they proved to the satisfaction of many scientific men that submarine boats really held vast possibilities as instruments of naval warfare.

France still retained its lead in furnishing new submarine projects. One of these put forward in 1861 by Olivier Riou deserves mention because it provided for two boats, one driven by steam and one by electricity. Both of these submarines were built, but inasmuch as nothing is known of the result of their trials, it is safe to conclude that neither of them proved of any practical value.

Two years later, in 1863, two other Frenchmen, Captain Bourgeois and M. Brun, built at Rochefort a submarine 146 feet long and 12 feet in diameter which they called the Plongeur. They fitted it with a compressed-air engine of eighty horse-power. Extensive trials were made with this boat but resulted only in the discovery that, though it was possible to sink or rise with a boat of this type without great difficulty, it was impossible to keep her at an even keel for any length of time.

During the next few years, undoubtedly as a result of the submarine activities during the Civil War, a number of projects were put forward in the United States, none of which, however, turned out successfully. One of them, for which a man by the name of Halstead was responsible, was a submarine built for the United States Navy in 1865. It was not tried out until 1872 and it was not even successful in living up to its wonderful name, The Intelligent Whale. Its first trial almost resulted in loss of life and was never repeated. In spite of this, however, the boat was preserved and may still be seen at the Brooklyn Navy Yard.

In the meantime, an invention had been made by an Austrian artillery officer which before long was to exert a powerful influence on submarine development, though it was in no sense a submarine boat. The manner in which the submarines had attacked their opponents during the Civil War suggested to him the need of improvements in this direction. As a result he conceived a small launch which was to carry the explosive without any navigators. Before he could carry his plans very far he died. A brother officer in the navy continued his work and finally interested the manager of an English engineering firm located at Fiume, Mr. Whitehead. The result of the collaboration of these two men was the Whitehead torpedo. A series of experiments led to the construction of what was first called a "Submarine Locomotive" torpedo, which not only contained a sufficient quantity of explosives to destroy large boats, but was also enabled by mechanical means to propel itself and keep on its course after having been fired. The Austrian Government was the first one to adopt this new weapon. Whitehead, however, refused to grant a monopoly to the Austrians and in 1870 he sold his manufacturing rights and secret processes to the British Government for a consideration of $45,000.

Before very long, special boats were built for the purpose of carrying and firing these torpedoes and gradually every great power developed a separate torpedo flotilla. Hand in hand with this development a large number of improvements were made on the original torpedo and some of these devices proved of great usefulness in the development of submarine boats.

The public interest in submarines grew rapidly at this time. Every man who was a boy in 1873, or who had the spirit of boyhood in him then,—or perhaps now,—will remember the extraordinary piece of literary and imaginative prophecy achieved by Jules Verne in his novel Twenty Thousand Leagues Under the Sea. Little about the Nautilus that held all readers entranced throughout his story is lacking in the submarines of to-day except indeed its extreme comfort, even luxury. With those qualities our submarine navigators have to dispense. But the electric light, as we know it, was unknown in Verne's time yet he installed it in the boat of his fancy. Our modern internal-combustion engines were barely dreamed of, yet they drove his boat. His fancy even enabled him to foresee one of the most amazing features of the Lake boat of to-day, namely the compressed air chamber which opened to the sea still holds the water back, and enables the submarine navigator clad in a diver's suit to step into the wall of water and prosecute his labors on the bed of the ocean. Jules Verne even foresaw the callous and inhuman character of the men who command the German submarines to-day. His Captain Nemo had taken a vow of hate against the world and relentlessly drove the prow of his steel boat into the hulls of crowded passenger ships, finding his greatest joy in sinking slowly beside them with the bright glare of his submarine electric lights turned full upon the hapless women and children over whose sufferings he gloated as they sank. The man who sank the Lusitania could do no more.

More and more determined became the attempts to build submarine boats that could sink and rise easily, navigate safely and quickly, and sustain human beings under the surface of the water for a considerable length of time. Steam, compressed air, and electricity were called upon to do their share in accomplishing this desired result. Engineers in every part of the world began to interest themselves in the submarine problem and as a result submarine boats in numbers were either projected or built between 1875 and 1900.

One of the most persistent workers in this period was a well-known Swedish inventor, Nordenfeldt, who had established for himself a reputation by inventing a gun which even to-day has lost nothing of its fame. In 1881 he became interested in the work which had been done by an English clergyman named Garret. The latter had built a submarine boat which he called the Resurgam (I shall rise)—thus neatly combining a sacred promise with a profane purpose. In 1879 another boat was built by him driven by a steam engine. Nordenfeldt used the fundamental ideas upon which these two boats were based, added to them some improvements of his own as well as some devices which had been used by Bushnell, and finally launched in 1886 his first submarine boat. The government of Greece bought it after some successful trials. Not to be outdone, Greece's old rival, Turkey, immediately ordered two boats for her own navy. Both of these were much larger than the Greek boat and by 1887 they had reached Constantinople in sections where they were to be put together. Only one of them, however, was ever completed. Characteristic Turkish delay intervened. The most typical feature of this boat was the fact that it carried a torpedo tube for Whitehead torpedoes. On the surface of the water this boat proved very efficient, but as an underwater boat it was a dismal failure. More than in any other craft that had ever been built and accepted, the lack of stability was a cause of trouble in the Nordenfeldt II. As soon as any member of the crew moved from one part of the boat to another, she would dip in the direction in which he was moving, and everybody, who could not in time take hold of some part of the boat, came sliding and rolling in the same direction. When finally such a tangle was straightened out, only a few minutes elapsed before somebody else, moving a few steps, would bring about the same deplorable state of affairs. The Nordenfeldt II. acted more like a bucking bronco than a self-respecting submarine boat and as a result it became impossible to find a crew willing to risk their lives in manning her. Before very long she had rusted and rotted to pieces. In spite of this lack of success, Nordenfeldt built a fourth boat which displayed almost as many unfortunate features as her predecessors and soon was discarded and forgotten.



In the latter part of the nineteenth century the French Government, which for so many years had shown a strong and continuous interest in the submarine problem, was particularly active. Three different types of boats built in this period under the auspices and with the assistance of the French Government deserve particular attention. The first of these was the Gymnote, planned originally by a well-known French engineer, Dupuy de Lome, whose alert mind also planned an airship and made him a figure in the history of our Panama Canal. He died, however, before his project could be executed. M. Gustave Zede, a marine engineer and his friend, continued his work after modifying some of his plans. The French Minister of Marine of this period, Admiral Aube who had long been strongly interested in submarines, immediately accepted M. Zede's design and ordered the boat to be built. As the earliest of successful submarines she merits description:



The Gymnote was built of steel in the shape of a cigar. She was 59 feet long, 5 feet 9 inches beam, and 6 feet in diameter, just deep enough to allow a man to stand upright in the interior. The motive power was originally an electro-motor of 55 horse-power, driven from 564 accumulators. It was of extraordinary lightness, weighing only 4410 pounds, and drove the screw at the rate of two thousand revolutions a minute, giving a speed of six knots an hour, its radius of action at this speed being thirty-five miles.

Immersion was accomplished by the introduction of water into three reservoirs, placed one forward, one aft, and one centre. The water was expelled either by means of compressed air or by a rotary pump worked by an electro-motor. Two horizontal rudders steered the boat in the vertical plane and an ordinary rudder steered in the horizontal.

The Gymnote had her first trial on September 4, 1888, and the Paris Temps described the result in the following enthusiastic language:

She steered like a fish both as regards direction and depth; she mastered the desired depth with ease and exactness; at full power she attained the anticipated speed of from nine to ten knots; the lighting was excellent, there was no difficulty about heating. It was a strange sight to see the vessel skimming along the top of the water, suddenly give a downward plunge with its snout, and disappear with a shark-like wriggle of its stern, only to come up again at a distance out and in an unlooked-for direction. A few small matters connected with the accumulators had to be seen to, but they did not take a month.

Following along the same lines as this boat another boat, considerably larger, was built. Before it was completed, M. Zede died and it was decided to name the new boat in his honour. The Gustave Zede was launched at Toulon on June 1, 1893; she was 159 feet in length, beam 12 feet 4 inches, and had a total displacement of 266 tons. Her shell was of "Roma" bronze, a non-magnetic metal, and one that could not be attacked by sea water.

The motive power was furnished by two independent electro-motors of 360 horse-power each and fed by accumulators. In order to endow the boat with a wide radius of action a storage battery was provided.

The successive crews of the Gustave Zede suffered much from the poisonous fumes of the accumulators, and during the earlier trials all the men on board were ill.

In the bows was a torpedo tube, and an arrangement was used whereby the water that entered the tube after the discharge of the torpedo was forced out by compressed air. Three Whitehead torpedoes were carried. In spite of the fact that a horizontal rudder placed at the stern had not proved serviceable on the Gymnote, such a rudder was fitted in the Gustave Zede. With this rudder she usually plunged at an angle of about 5 deg., but on several occasions she behaved in a very erratic fashion, seesawing up and down, and once when the Committee of Experts were on board, she proved so capricious, going down at an angle of 30 deg.-35 deg., often throwing the poor gentlemen on to the floor, that it was decided to fix a system of six rudders, three on each side.

Four water tanks were carried, one at each end and two in the middle, and the water was expelled by four pumps worked by a little electro-motor; these pumps also furnished the air necessary for the crew and for the discharge of the torpedoes. For underwater vision, an optical tube and a periscope had been provided.

On July 5, 1899, still another submarine boat was launched for the French Navy. She was called the Morse. She was 118 feet long, 9 feet beam, displaced 146 tons, and was likewise made of "Roma" bronze. The motive power was electricity and in many other respects she was very similar to the Gustave Zede, embodying, however, a number of improvements. M. Calmette, who accompanied the French Minister of War on the trial trip of the Morse, described his experience in the Paris Figaro as follows:

General Andre, Dr. Vincent, a naval doctor, and I entered the submarine boat Morse through the narrow opening in the upper surface of the boat. Our excursion was to begin immediately; in two hours we came to the surface of the water again three miles to the north to rejoin the Narval. Turning to the crew, every man of which was at his post, the commandant gave his orders, dwelling with emphasis on each word. A sailor repeated his orders one by one, and all was silent. The Morse had already started on its mysterious voyage, but was skimming along the surface until outside the port in order to avoid the numerous craft in the Arsenal. To say that at this moment, which I had so keenly anticipated, I did not have the tremor which comes from contact with the unknown would be beside the truth. On the other hand, calm and imperturbable, but keenly curious as to this novel form of navigation, General Andre had already taken his place near the commandant on a folding seat. There were no chairs in this long tube in which we were imprisoned. Everything was arranged for the crew alone, with an eye to serious action. Moreover, the Minister of War was too tall to stand upright beneath the iron ceiling, and in any case it would be impossible to walk about.

The only free space was a narrow passage, sixty centimetres broad, less than two metres high, and thirty metres long, divided into three equal sections. In the first, in the forefront of the tube, reposed the torpedoes, with the machine for launching them, which at a distance of from 500 to 600 metres were bound to sink, with the present secret processes, the largest of ironclads. In the second section were the electric accumulators which gave the light and power. In the third, near the screw, was the electric motor which transformed into movement the current of the accumulators. Under all this, beneath the floor, from end to end, were immense water ballasts, which were capable of being emptied or filled in a few seconds by electric machines, in order to carry the vessel up or down. Finally, in the centre of the tube, dominating these three sections, which the electric light inundated, and which no partition divided, the navigating lieutenant stood on the lookout giving his orders.

There was but one thing which could destroy in a second all the sources of authority, initiative, and responsibility in this officer. That was the failure of the accumulators. Were the electricity to fail everything would come to a stop. Darkness would overtake the boat and imprison it for ever in the water. To avoid any such disaster there have been arranged, it is true, outside the tube and low down, a series of lead blades which were capable of being removed from within to lighten the vessel. But admitting that the plunger would return to the surface, the boat would float hither and thither, and at all events lose all its properties as a submarine vessel. To avoid any such disaster a combination of motors have been in course of construction for some months, so that the accumulators might be loaded afresh on the spot, in case of their being used up.

The Morse, after skimming along the surface of the water until outside the port, was now about to sink. The commandant's place was no longer in the helmet or kiosque whence he could direct the route along the surface of the sea. His place was henceforth in the very centre of the tube, in the midst of all sort of electric manipulators, his eyes continually fixed on a mysterious optical apparatus, the periscope. The other extremity of this instrument floated on the surface of the water, and whatever the depth of the plunge it gave him a perfectly faithful and clear representation, as in a camera, of everything occurring on the water.

The most interesting moment of all now came. I hastened to the little opening to get the impression of total immersion. The lieutenant by the marine chart verified the depths. The casks of water were filled and our supply of air was thereby renewed from their stores of surplus air. In our tiny observatory, where General Andre stationed himself above me, a most unexpected spectacle presented itself as the boat was immersed.

The plunge was so gentle that in the perfect silence of the waters one did not perceive the process of descent, and there was only an instrument capable of indicating, by a needle, the depth to which the Morse was penetrating. The vessel was advancing while at the same time it descended, but there was no sensation of either advance or roll. As to respiration, it was as perfect as in any room. M. de Lanessan, who since entering office has ordered eight more submarine vessels, had concerned himself with the question as a medical man also, and, thanks to the labours of a commission formed by him, the difficulties of respiration were entirely solved. The crew were able to remain under water sixteen hours without the slightest strain. Our excursion on this occasion lasted scarcely two hours. Towards noon, by means of the mysterious periscope, which, always invisible, floated on the surface and brought to the vessel below a reflection of all that passed up above, the captain showed us the Narval, which had just emerged with its two flags near the old battery Impregnable. From the depths in which we were sailing we watched its slightest manoeuvres until the admiral's flag, waving on the top of a fort, reminded us that it was time to return.



CHAPTER XIII

JOHN P. HOLLAND AND SIMON LAKE

The Naval Committee of the House of Representatives of the United States in the early part of 1900 held a meeting for the purpose of hearing expert testimony upon the subject of submarines. Up to then the United States authorities had shown, as compared with the ruling powers of other navies, only a limited amount of interest in the submarine question. Increased appropriations for the construction of submarine boats which were then beginning to become more frequent in other countries acted, however, as a stimulus at this time.

The committee meeting took place a few days after some of the members of the committee, together with a number of United States navy officers, had attended an exhibition of a new submarine boat, the Holland No. 9.

The late Admiral Dewey gave the following opinion about this submarine to the committee, an opinion which since then has become rather famous:

Gentlemen: I saw the operation of the boat down off Mount Vernon the other day. Several members of this committee were there. I think we were very much impressed with its performance. My aid, Lieutenant Caldwell, was on board. The boat did everything that the owners proposed to do. I said then, and I have said it since, that if they had two of those things at Manila, I could never have held it with the squadron I had. The moral effect—to my mind, it is infinitely superior to mines or torpedoes or anything of the kind. With two of those in Galveston all the navies of the world could not blockade the place.

Admiral Dewey's approval of the Holland No. 9 undoubtedly exerted a considerable influence on the Naval Committee and as a result of its recommendations the United States Government finally purchased the boat on April 11, 1900, for $150,000. This amount was about $86,000 less than the cost of building to the manufacturers, the Holland Torpedo Boat Company. The latter, however, could well afford to take this loss because this first sale resulted a few months afterwards—on August 25th—in an order for six additional submarines. The British Government also contracted in the fall of the same year for five Hollands. The navy of almost every power interested in submarines soon followed the lead of the British Admiralty. Submarines of the Holland type were either ordered outright, or else arrangements were concluded permitting the use of the basic patents held by the Holland Company. It will be noted that the United States Government having discovered that it had a good thing benevolently shared it with the governments that might be expected to use it against us.



The Holland No. 9, as her very name indicates, was one of a long line of similar boats. As compared with other experimental submarine boats she was small. She was only fifty-three feet ten inches long, and ten feet seven inches deep. Although these proportions made her look rather thickset, they were the result of experimental work done by the builder during a period of twenty-five years. She was equipped both with a gasoline engine of fifty horse-power and an electric motor run by storage batteries. The latter was intended for use when the boat was submerged, the former when she was travelling on the surface of the water. She was capable of a maximum speed of seven knots an hour. Her cruising radius was 1500 miles and the combination of oil and electric motors proved so successful that from that time on every submarine built anywhere adopted this principle. Two horizontal rudders placed at the stern of the boat steered her downward whenever she wanted to dive and so accomplished a diver was this boat that a depth of twenty-eight feet could be reached by her in five seconds. Her conning tower was the only means of making observations. No periscopes had been provided because none of the instruments available at that time gave satisfaction. This meant that whenever she wished to aim at her target it was necessary for her to make a quick ascent to the surface. Her stability was one of her most satisfactory features. So carefully had her proportions been worked out that there was practically no pitching or rolling when the boat was submerged. Even the concussion caused by the discharge of a torpedo was hardly noticeable because arrangements had been made to take up the recoil caused by the firing and to maintain the balance of the boat by permitting a quantity of water equal to the weight of the discharged torpedo to enter special compartments at the very moment of the discharge.