Thus these various peculiarities of the motion of our satellite are exhibited by comparatively simple means—the number of moving parts being, it is believed, as small as it can be made; and the substitution of a crank motion for the usual train of wheels, we think, is a new device.

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THE UPRIGHT ATTITUDE OF MANKIND.

Every one must have heard or have read of the supposed perfect adaptation of the human frame to bipedal locomotion and to an upright attitude, as well as the advantages which we gain by this erect position. We are told, and with perfect truth, that in man the occipital foramen—the aperture through which the brain is connected with the spinal cord—is so placed that the head is nearly in equilibrium when he stands upright. In other mammalia this aperture lies further back, and takes a more oblique direction, so that the head is thrown forward, and requires to be upheld partly by muscular effort and partly by the ligamentum nuch, popularly known in cattle as the "pax-wax."

Again, the relative lengths of the bones of the hinder extremities in man form an obstacle to his walking on all-fours. If we keep the legs straight we may touch the ground in front of our feet with the tips of the fingers, but we cannot place the palms of the hands upon the ground and use them to support any part of our weight in walking. Not a few other points of a similar tendency have been so often enlarged upon, in works of a teleological character, that there can be no need even to specify them at present.

But till lately it has never been asked, "Is man's adaptation to an upright posture perfect?" and "Is this posture attended with no drawbacks?" These questions have been raised by Dr. S. V. Clevenger in a lecture delivered before the Chicago University Club, on April 18, 1882, and recently published in the American Naturalist. This lecture, we may add, cost the speaker the chair of Comparative Anatomy and Physiology at the Chicago University!

Dr. Clevenger first discusses the position of the valves in the veins. The teleologists have long told us that the valves in the veins of the arms and legs assist in the return of blood to the heart against gravitation. But what earthly use has a man for valves in the intercostal veins which carry blood almost horizontally backward to the azygos veins? When recumbent, these valves are an actual obstacle to the free flow of the blood. The inferior thyroid veins which drop their blood into the innominate are obstructed by valves at their junction. Two pairs of valves are situate in the external jugular, and another pair in the internal jugular, but they do not prevent regurgitation of blood upward.

An anomaly exists in the absence of valves from parts where they are most needed, such as the ven cav, the spinal, iliac, hmorrhoidal, and portal veins.

But if we place man upon all-fours these anomalies disappear, and a law is found regulating the presence or absence of valves, and, according to Dr. Clevenger, it is applicable to all quadrupeds and to the so-called Quadrumana. Veins flowing toward the back, i.e., against gravitation in the all-fours posture—are fitted with valves; those flowing in other directions are without. For the few exceptions a very feasible explanation is given.

Valves in the hmorrhoidal veins would be useless to quadrupeds; but to man, in his upright position, they would be very valuable. "To their absence in man many a life has been and will be sacrificed, to say nothing of the discomfort and distress occasioned by the engorgement known as piles, which the presence of valves in their veins would obviate."

A noticeable departure from the rule obtaining in the vascular system of mammalia also occurs to the exposed situation of the femoral artery in man. The arteries lie deeper than the veins, or are otherwise protected, for the purpose—as a teleologist would say—of preventing serious loss of blood from superficial cuts. Translating this view into evolutionary language, it appears that only animals with deeply placed arteries can survive and transmit their structural peculiarities to their offspring. The ordinary abrasions to which all animals are exposed, not to mention their onslaughts upon each other, would quickly kill off species with superficially placed arteries. But when man assumed the upright posture the femoral artery, which in the quadrupedal position is placed out of reach on the inner part of the thigh, became exposed. Were not this defect greatly compensated by man's ability to protect this part in ways not open to brutes, he, too, might have become extinct. As it is, this exposure of so large an artery is a fruitful cause of trouble and death.

We may here mention some other disadvantages of the upright position which Dr. Clevenger has omitted. Foremost comes the liability to fall due to an erect posture supported upon two feet only. Four-footed animals in their natural haunts are little liable to fall; if one foot slips or fails to find hold, the other three are available. If a fall does occur on level ground, there is very little danger to any mammal nearly approaching man in bulk and weight. Their vital parts, especially the heart and the head, are ordinarily so near the ground that to them the shock is comparatively slight. To human beings the effects of a fall on smooth, level ground are often serious, or even deadly. We need merely call to mind the case of the illustrious physicist whom we have so recently and suddenly lost.

The upright attitude involves a further sourge of danger. In few parts (if any) of the body is a blow more fatal than over what is popularly called the "pit of the stomach." In the quadruped this part is little exposed either to accidental or intentional injuries. In man it is quite open to both. A blow, a kick, a fall among stones, etc., may thus easily prove fatal.

Another point is the exposure and prominence of the generative organs, which in most other animals are well protected. Leaving danger out of the question, it may be asked whether we have not here the origin of clothing? The assumption of the upright posture may have made primitive man aware of his nakedness.

Returning to the illustrations furnished by Dr. Clevenger, we are reminded that another disadvantage which occurs from the upright position of man is his greater liability to inguinal hernia. In quadrupeds the main weight of the abdominal viscera is supported by the ribs and by strong pectoral and abdominal muscles. The weakest part of the latter group of muscles is in the region of Poupart's ligament, above the groin. Inguinal hernia is rare in other vertebrates because this weak part is relieved by the pressure of the viscera. In man the pelvis receives almost the entire load of the intestines, and hence Art is called in to compensate the deficiencies of nature, and an immense number of trusses have to be manufactured and used. It is calculated that 20 per cent. of the human family suffer in this way. Strangulated hernia frequently causes death. The liability to femoral hernia is in like manner increased by the upright position.

Now, if man has always been erect from his creation—or, if that term be disliked, from his origin—we have evidently nothing to hope from the future in the way of an amendment of this and other defects. But if we have sprung from a quadrupedal animal, and have by degrees adopted an upright position, to which we are as yet imperfectly adapted, the muscular tissues of the abdomen will doubtless in the lapse of ages become strengthened to meet the demand made upon them, so that the liability to rupture will decrease. In like manner the other defects above enumerated may gradually be rendered less serious.

A most important point remains; the peritoneal ligaments of the uterus fully subserve suspensory functions. The anterior, posterior, and lateral ligaments are mainly concerned in preventing the gravid uterus, in quadrupeds, from pitching too far forward toward the diaphragm. The round ligaments are utterly unmeaning in the human female, but in the lower animals they serve the same purpose as the other ligaments. Prolapsus uteri, from the erect position and the absence of supports adapted to the position, is thus rendered common, destroying the health and happiness of multitudes.

As a simple deduction from mechanical laws, it would readily follow that any animal or race of men which had for the longest time maintained an erect position would have straighter abdomens, wider pelvic brims with contracted pelvic outlets, and that the weight of the spinal column would force the sacrum lower down. This, generally speaking, we find to be the case. In quadrupeds the box-shaped pelvis, which admits of easy parturition, is prevalent. Where the position of the animal is such as to throw the weight of the viscera into the pelvis, the brim necessarily widens, these weighty organs sink lower, and the beads of the thigh-bones acting as fulcra permit the crest of the ilium to be carried outward, while the lower part of the pelvis is at the same time contracted.

In the innominate bones of a young child the box-shape exists, while its prominent abdomen resembles that of the gorilla. The gibbon exhibits this iliac expansion through the sitting posture which developed his ischial callosities. Similarly iliac expansion occurs in the chimpanzee. The megatherium had wide iliacal expansions due to its semi-erect habits; but as its weight was in great part supported by the huge tail, and as the fermora rested in acetabula placed far forward, the leverage necessary to contract the lower portion of the pelvis was absent.

Prof. Weber, of Bonn, quoted in Karl Vogt's "Vorlesungen ueber den Mensohen," distinguishes four chief forms of the pelvis in mankind—the oval in Aryans, the round among the Red Indians, the square in the Mongols, and the wedge-shaped in the Negro. Examining this question mechanically it would seem that the longer a race had remained in an upright position the lower is the sacrum, and the greater is the tendency to approximate to the larger lateral diameter of the European female. The front to back diameter of the ape's pelvis is usually greater than the measurement from side to side. A similar condition affords the cuneiform, from which it may be inferred that the erect position in the Negro has not been maintained so long as in the Mongol, whose pelvis has assumed the quadrilateral shape owing to persistence of spinal axis weight for a greater time. This pressure has finally culminated in forcing the sacrum of the European nearer the pubes, with consequent lateral expansion and contraction of the diameter from front to back. From the marsupials to the lemurs the box-shaped pelvis remains. With the wedge-shape occasioned in the lowest human types there occurs a further remarkable phenomenon in the increased size of the foetal head accompanying the contraction of the pelvic outlet. While the marsupial head is about one-sixth the size of the narrowest part of the bony parturient canal, the moment we pass to erect animals the greater relative increase is there seen in cranial size, with a coexisting decrease in the area of the outlet. This altered condition of things has caused the death of millions of otherwise perfectly healthy and well-formed human mothers and children. The palontologist might tell us if some such case of ischial approximation by natural mechanical causes has not caused the probable extinction of whole genera of vertebrates. "If we are to believe that for our original sin the pangs and labor of childbirth were increased, and if we also believe in the disproportionate contraction of the pelvic space being an efficient cause of the same difficulties of parturition, the logical inference is that man's original sin consisted in his getting upon his hind legs."

This subject is not without direct applications. Accoucheurs cause their patients to assume what is called the knee-chest position, a prone one, for the purpose of restoring the uterus to something near a natural position. Brown-Sequard recommends, in myelitis, or spinal congestion, drawing away the blood from the spine by placing the patient on his abdomen or side, with hands and feet somewhat hanging down. The liability to spina bifida is greatest in the human infant, through the stress thrown on the spine. The easy parturition in the lower human races is due to the discrepancy between cranial and pelvic sizes not having been as yet reached by those races. The Sandwich Island mother has a difficult delivery only when her child is half white, and has consequently a longer head than the unmixed native strain.

At present the world goes on in its blindness, apparently satisfied that everything is all right because its exists, ignorant of the evil consequences of apparently beneficial pecularities, vaunting man's erectness and its advantages, while ignoring the disadvantages.

The observation that the lower the animal the more prolific (not universally true!) would warrant the belief that the higher the animal the more difficulties encompass its propagation and development. The cranio-pelvic difficulty may perhaps settle the Malthusian question as far as the higher races of men are concerned by their extinction.

[If the facts brought forward by Dr. Clevenger cannot be controverted, they seem to prove that man must have originated by gradual development from a four-footed being. Had he been created an erect, bipedal animal, as we find him, his structure would have been not in partial, but in perfect, adaptation to the conditions of that attitude. That some of the peculiarities of his structure are better in harmony with a horizontal than a vertical position of the spinal column, is perhaps the strongest argument against the theory of direct creation and the radical toto coelo distinction between man and beast that has yet been advanced. We cannot at the moment lay our hands upon any thorough and trustworthy account of the valves in the veins of the sloth: as that animal spends its life hanging, back downward, the structure of the veins would be interesting in this connection.—ED. J. S.]—Journal of Science.

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OUR ENEMIES, THE MICROBES.

We have seen the microbes, as our servants[1], often performing, unbeknown to us, the work of purifying and regenerating the soil and atmosphere. Let us now examine our enemies, for they are numerous. Everywhere frequent—in the air, in the earth, in the water—they only await an occasion to introduce themselves into our body in order to engage in a contest for existence with the cells that make up our tissues; and, often victorious, they cause death with fearful rapidity. When we have named charbon, septicmia, diphtheria, typhoid fever, pork measles, etc., we shall have indicated the serious affections that microbes are capable of engendering in the animal organism.

[Footnote 1: SUPPLEMENT, No. 446, page 7125.]

We call those diseases "parasitic" that are occasioned by the introduction of a living organism into the bodies of animals. Although a knowledge of such diseases is easy where it concerns parasites such as acari and worms, it becomes very difficult when it is a question of diseases that are caused by the Bacteriace. In fact, the germs of these plants exist in the air in large quantities, as is shown by the analysis of pure air by a sunbeam, and we are obliged to take minute precautions to prevent then from invading organic substances. If, then, during an autopsy of an individual or animal, a microscopic examination reveals the presence of microbes, we cannot affirm that the latter were the cause of the affection that it is desired to study, since they might have introduced themselves during the manipulation, and by reason of their rapid vegetation have invaded the tissues of the dead animal in a very short time. The presumption exists, nevertheless, that when the same form of bacteria is present in the same tissue with the same affection, it is connected with the disease. This was what Davaine was the first to show with regard to Bacillus anthracis, which causes charbon. He, in 1850, having examined the blood of an animal that had died of this disease, found therein amid the globules (Fig. 1), small, immovable, very narrow rods of a length double that of the blood corpuscles. It was not till 1863 that he suspected the active role of these organisms in the charbon malady, and endeavored to demonstrate it by experiments in inoculation. Is the presence of these little rods in the blood of an animal that has died of charbon sufficient of itself to demonstrate the parasitic nature of the affection? No; in order that the demonstration shall be complete, the bacteria must be isolated, cultivated in a state of purity in proper liquids, and then be used to inoculate animals with. If the latter die with all the symptoms of charbon, the demonstration will be complete. Davaine did, indeed, perform some experiments in inoculation that were successful, but his results were contradicted by the experiments of Messrs. Jaillard and Leplat, and those of Mr. Bert concerning the toxic influence of oxygen at high tension upon microbes. As Davaine was unable to explain the contradiction between his results and those of Messrs. Jaillard, Leplat, and Bert, minds were not as yet convinced, notwithstanding the support that his ideas received from Mr. Koch's researches.

In 1877 Mr. Pasteur took up Davaine's experiments, and confirmed his affirmations step by step by employing the method of culture that he had used with such success in his studies upon fermentation. He isolated Davaine's bacterium by cultivating it in a decoction of beer yeast that had been previously sterilized (Fig. 2); and after from ten to twenty cultures, he found that a portion of the liquid containing a few bacteria, when used for inoculating a rabbit, quickly caused the latter to die of charbon, while the same liquid, when filtered through plaster or porcelain, became harmless.

Davaine's bacterium develops exclusively in the blood, and is never found at any depth in the tissues. This is due to the fact that the alga, having need of oxygen in order to live, borrows its flow from the blood, and thus extracts from the globules that which they should have carried to the tissue. The animal therefore dies asphyxiated. It is on account of the absence of oxygen in the blood that the latter assumes the blackish-brown color that characterizes the malady, and that has given its name of charbon (coal).

The parasitic nature of charbon was therefore absolutely demonstrated, first, by the constant presence of Bacillus anthracis in the blood of anthracoid animals, and second, by the pure culture of the parasite and the inoculation of animals with charbon by means of it.

Davaine began the demonstration in 1863, and Pasteur finished it in 1877. These facts are now incontestable; yet, to show how slowly truth is propagated, even in these days of telegraphs and telephones, there might have been read a few months ago, in an interesting article on microbes, by Dr. Fol, a distinguished savant, the statement that charbon and tuberculosis were discovered by Dr. Koch!

New parasitic affections, whose existence was suspected, were soon discovered and scientifically demonstrated, such, for example, as septicmia, or the putrefaction which occurs in living animals, which in ambulances causes so fearful havoc among the wounded, and which proceeds from Bacillus septicus. This parasite exhibits itself under the form of little articulated rods that live isolated from oxygen in the mass of the tissues, and disorganize the latter in disengaging a large quantity of putrid gas. Other parasites of this class are the micrococcus of chicken cholera (Fig. 3), the micrococcus of hog measles, and the Spirochoete Obermeieri of recurrent fever, discovered by Obermeier (Fig. 5).

Besides these, there are a certain number of maladies that seem as if they must be due to the Bacteriace, although a demonstration of the fact by the method of cultures and inoculation has not as yet been attempted. Among such, we may cite typhoid fever, diphtheria, murrain, tuberculosis (Fig. 4), malarial fever (Fig. 6), etc.

As may be seen, the list is already a long one, and it tends every day to still further increase. All the progress that has been made in so few years in our knowledge of contagious or epidemic diseases is due exclusively to M. Pasteur and the scientific method that he introduced through his remarkable labors on fermentation. Now that we know our most formidable enemies, how shall we defend ourselves against them?

As we have seen, bacteria exist everywhere, mixed with the dust that interferes with the transparency of the air and covers all objects; and they are likewise found in water.

Under normal conditions, our body is closed to these organisms through the epidermis and epithelium, and, as has been shown by Mr. Pasteur, no bacteria are found in the blood and tissues of living animals. But let a rupture or wound occur, and bacteria will enter the body, and, when once the enemy is in place, it will be too late. One sole chance of safety remains to us, and that is that in the warfare that it is raging against our tissues the enemy may succumb. M. Pasteur has shown that the blood corpsucles sometimes engage in the contest against bacterides and come off victorious. In fact, chickens are proof against poisoning by charbon, because, owing to the high temperature of their blood, the bacterides are unable to extract oxygen from the corpuscles thereof. But, if the chickens be chilled, the conditions are changed, and they will die of charbon just as do cattle and sheep; but, as the result of the contest cannot always be foreseen, it is necessary at any cost to prevent bacterides from entering the body.



Under ordinary circumstances a severe hygiene will suffice to preserve us; if a wound is received it should be washed with water mixed with antiseptics, such as phenic acid, borax, or salicylic acid. If water is impure, it must be boiled and then aerated before it is drunk. If the air is the vehicle of the germs of the disease, it will have to be filtered by means of a muslin curtain kept wet with a hygroscopic solution, glycerine for example. Finally, when, after an epidemic, contaminated apartments are to be occupied, the walls and floor and the clothing must be washed with antiseptic solutions whose nature will vary according to circumstances—steam charged with phenic acid, water mixed with a millionth part of sulphuric acid, boric acid, ozone, chlorine, etc.

These preventives only prove efficient on condition that they be used persistently. Let our vigilance be lacking for an instant, and the enemy will enter to work destruction, for it only requires a spore less than a hundredth of a millimeter in diameter to produce the most serious affections.

Fortunately, and it is again to Mr. Pasteur that we owe these wonderful discoveries, the parasitic microbes themselves, which sow sickness and death, may, through proper culture, become true vaccine viri that are capable of preserving the organism against any future attack of the disease that they were capable of producing; such vaccine matters have been discovered for charbon, chicken cholera, the measles of swine, etc.

When the micrococcus of chicken cholera (Fig. 3.) is cultivated, it is seen that the activity of the microbe in cultures exposed to the air gradually diminishes. While a drop of the liquid would, in twenty-four hours, have killed all the chickens that were inoculated with it, its effect after two, three, or four days considerably diminishes, and an inoculation with it produces nothing more than a slight indisposition in the animal, and one that is never followed by a serious accident. It is then said that the virulence of the microbe is attenuated.

The air is the agent of this transformation that gradually renders the bacteria benign, for in cultures made under the same circumstances as the preceding, but with the absence of air, the activity of these alg is preserved for days or weeks, and they will then cause death just as surely as they would have done at the end of one day.

What is remarkable is that animals inoculated with the attenuated micrococcus become for a varying length of time refractory to the action of the most formidable parasites of this kind. Mr. Pasteur has discovered two such vaccine viri—one for chicken cholera and the other for charbon. His results have not been accepted without a struggle, and it required nothing less than public experiment in vaccination, both in France and abroad, to convince the incredulous. There are still people at the present time who assert that Mr. Pasteur's process of vaccination has not a great practical range! And yet, here we have the results; more than 400,000 animals have been vaccinated since 1881, and it has been found that the mortality is ten times less in these than in those that have not been vaccinated!

An impetus has now been given, and we can look to the future with confidence, for, if our enemies are numerous, the use of a severe hygiene and preventive vaccination will permit us to gradually free humanity from the terrible scourges that sap the sources of fortune and life.—Science et Nature.

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THE WINE FLY.

At the last meeting of the New York Microscopical Society, a paper was read by Dr. Samuel Lockwood, secretary of the New Jersey State Microscopical Society. His subject was the Wine Fly, Drosophila ampelophila. The paper was a contribution to the life-history of this minute insect. He had given in part three years to its study, beginning in September, 1881, when nothing whatever of its life-history seemed to have been known. In October the flies attacked his Concords. He found upon a grape which he was inspecting with a pocket-lens an extremely small white egg; but lost it. The grapes when brought on the table were infested by the flies, which proved to be the above mentioned species. When driven from the grapes they would fly to the window, where he captured two of them These were placed in a jar with a grape for food. In two days he found one egg on the outer skin of the grape. The laying was kept up for four or five days, until there were about thirty, some on the outside of the grape and some at an opening where the two flies had fed. The egg had a pair of curious suspenders near the end where the mouth of the larva would develop. These suspenders were attached at their ends to the grape, but where the egg was laid in the soft part of the fruit the suspenders were spread out at the surface; thus the larva would emerge clean from the shell. The egg was 0.5 mm. in length, and about a fourth of that in width. The larva when grown was at least four times as long as the egg. As the larva burrowed in the juices of the fruit, two quite prominent breathing tubes at the posterior end were kept in the air. Between these cardinal tubes were several teat-like points, much smaller, but having a similar function.

The larvae appeared in five days after the eggs were laid. In about as many more days the puparium state would be entered, and in about six days more the fly or imago would appear. In ovipositing the suspensors would leave the oviparous duct last. The paper claimed that the curious shape of the egg compelled the female to oviposit slowly, as it took time for the egg to assume its form; hence, the eggs were not laid in strings or masses, but singly and at considerable intervals.

The flies are very hairy, especially the females. The neck and even the eyes are very hirsute. The eyes are red, quite large and pretty, though somewhat outre under the microscope, for from between the little lenses are projecting, straight, stiff hairs. As the insect is quite active, it must be that this fringing of the tiny eyelets with hair does not materially obscure its vision. When the minuteness of this singular arrangement is considered, it is surely remarkable. This general hairiness of the female especially, and that about the head, neck, and forward part of the thorax, stands correlated to a beautiful structure found only in the male, which has on the tarsus of each leg in the forward pair what the lecturer called a sexual comb. It is a beautiful comb of a very dark brown color, each comb having ten pointed and strong teeth. In the nuptial embrace these combs are fixed in the hairy front of the thorax of the female, thus becoming little grapnels.

The flies love any vegetable substance in fermentation, whether acetic or vinous. Hence it will abound about cider mills, swarm on preserves in the pantry, and in cellars or places where wine is being made or stored. The paper showed the tendency of the glucose in the over-ripe grape to the vinous ferment, and that the fly delighted in it. A singular accident showed how they loved even the very high spirits. In making some of the mounts shown to the society, Dr. Lockwood had left a bottle of 90 per cent. alcohol uncorked over night. Next morning he was astonished to find his alcohol of a beautiful amethystine color, and the cork out. Inspection showed a number of these tiny creatures, which, when filled with the purple juice of the grape, had smelt the alcohol in the open bottle, and had gone in to drink. They had ignominiously perished, and had given color to the liquid.—Micro. Journal.

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[NATURE.]



THE "POTETOMETER," AN INSTRUMENT FOR MEASURING THE TRANSPIRATION OF WATER BY PLANTS.

In view of the interest now attaching to recent advances in vegetable physiology, it seems not unlikely that a description of the instrument bearing the above name, lately published by Moll (Archives Neerlandaises, t. xviii.), will serve as useful purpose. The apparatus was designed to do away with certain sources of error in Sachs' older form of the instrument, described in his "Experimental Physiologie"—errors chiefly due to the continual alteration of pressure during the progress of the experiment.

As shown in the diagram, the "potetometer" consists essentially of a glass tube, a d, open at both ends, and blown out into a bulb near the lower end; an aperture also exists on either side of the bulb at or about its equator. The two ends of the main tube are governed by the stopcocks, a and d, and the greater length of the tube is graduated. A perforated caoutchouc stopper is fitted into one aparture of the bulb, e, and the tube, g k, fits hermetically to the other. This latter tube is dilated into a cup at h to receive the caoutchouc stopper, into which the end of the shoot to be experimented upon is properly fixed.

The fixing of the shoot is effected by caoutchouc and wire or silk, as shown at i, and must be performed so that the clean-cut end of the shoot is exactly at the level of a tube passing through the perforated stopper, e, of the bulb; this is easily managed, and is provided for by the bending of the tube, g h. The tube, f, passing horizontally through the caoutchouc stopper, e, is intended to admit bubbles of air, and so equalize the pressure and at the same time afford a means of measuring the rapidity of the absorption of water by the transpiring shoot. This tube (see Fig. 2, f) is a short piece of capillary glass tubing, to which is fixed a thin sheath of copper, b', which slides on it, and supports a small plate of polished copper, a', in such a manner that the latter can be held vertically at a small distance from the inner opening of the tube, and so regulate the size of the bubble of air to be directed upward into the graduated tube, a b.



The apparatus is filled by placing the lower end of the main tube under water, closing the tubes, f and i (with caoutchouc tubing and clips), and opening the stopcocks, a and d. Water is then sucked in from a, and the whole apparatus carefully filled. The cocks are then turned, and the cut end of the shoot fixed into i, as stated; care must be taken that no air remains under the cut end at i, and the end of the shoot must be at the level, k l. This done, the tube, f, may then be opened.

The leaves of the shoot transpire water, which is replaced through the stem at the cut end in i from the water in the apparatus. A bubble of air passes through the tube, f, and at once ascends into the graduated tube, a c. The descent of the water-level in this tube—which may conveniently be graduated to measure cubic millimeters—enables the experimenter at once to read off the amount of water employed in a given time.

It is not necessary to dwell on obvious modifications of these essentials, nor to speak of the slight difficulties of manipulation (especially with the tube, f). Of course the apparatus might be mounted in several ways; and excellent results for demonstration in class could be obtained by arranging the whole on one of the pans of a sensitive balance. H. MARSHALL WARD.

Botanical Laboratory, Owens College.

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BOLIVIAN CINCHONA FORESTS.

The great progress made in the acclimation of cinchona trees in India, Ceylon, and elsewhere has awakened the governments of countries where the plants are indigenous to the necessity of conserving from reckless destruction, and replanting denuded forests, so as to be able to keep up the supply of this valuable product.

In Bolivia, since 1878, according to the report of the Netherlands Consul, private individuals and land owners have taken up the question with great earnestness, and at the present time on the banks of the Mapiri, in the department of La Paz, there are over a million of young trees growing.

New plantations have also sprung up in various other localities, either on private ground or that owned by Government. The competition of India and Ceylon in supplying the markets has had also the effect of inducing more care in collecting and also of revisiting old spots, often with the result of a rich harvest of bark which had been left on partly denuded trunks, and the opening up of new localities. The new shoots springing up from the old stumps have yielded much quill bark, and the root bark of the old stumps has also been utilized.

The replanting entails very little expense. The Indian tenant on an estate has a house and land from the owner (hacienda) of the estate. For this he binds himself to work for two to four days a week, at from 28 to 36 cents per day, women and children obtaining 16 to 21 cents per day. Thus the planting, weeding, etc., during the first two years is but nominal in expense; after this period the trees may be left to themselves.

On Government land the expense is greater, as, after an application being made, the land is put up to public auction, and may fetch a very low or higher price according to the bidding. The land secured, contracts are made with natives of the lower class to clear the forest and plant cinchona. The contracts are often sublet to Indians. The young plants are planted from five to six feet apart, with banana trees between, on account of their rapid growth and the shade the latter afford. From March to June, after the wet season is over, is the best time for planting, and the contractor keeps the plantation free from weeds and in good order for twelve months, when it is handed over to the owner. The following is given as the cost of the Mapiri River plantation of an area from 60 or more miles in extent:

Ground. $1,200 300,000 plants at $0.14. 42,000 Superintendent, buildings, etc. 4,400 Interest. 4,800 ———- Total. $52,400

Till the plants are above two years of age, they are liable to die from drought or the attacks of ants, and during 1878 many thousands died from these causes. At the end of the fourth year some proprietors begin to collect the quill bark by the method of coppicing.

It is feared by some that, should this new venture be successful, it will prove a dangerous rival to the plantations of India, Ceylon, and Java, and lower the price of bark considerably.—Jour. Society of Arts.

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FERNS.

N. Davallioides Furcans.—Among the many crested ferns in cultivation, this, of which the annexed is an illustration, is one of the most distinct; so different indeed it is from the type, that it is questionable if it really is a form of it; the most essential characteristic, that of the fructification at the extreme edge of the lobes of the pinn, is altogether absent, and the whole habit of the plant is also thoroughly distinct. It is of equally robust growth, but its handsomely arching fronds, which are from 3 feet to 4 feet in length, are produced in great abundance from a central tuft or agglomeration of crowns. Its most distinct characteristic is the furcation of the pinn, which are all of the same dimensions, whether sterile or fertile; they are all opposite and closely set along the mid-rib, whereas those of N. davallioides are set much further apart. In the barren pinn which are only situated on the lower portion of the frond, and which generally are only few in number, the furcation is rudimentary; in the fertile pinn it is twice and even three times repeated in the extremities of the first division, becoming more complex toward the point of the frond, where it often forms quite a large tassel, whose weight gives the fronds quite an elegant, arching habit. On that account this plant is valuable for growing in baskets of large dimensions, in which it shows itself off to good advantage, and never fails to prove attractive. Although it produces spores freely, it is best to propagate it by means of the young plants produced from rhizomes in the ordinary way, on account of the extreme variations which take place among the seedlings, a small percentage only of which are possessed of the true character of the parent plant. Stove.—The Garden.



N. Duffi.—This pretty, neat-habited species, of which an illustration, kindly lent us by Mr. Bull, appears in another place, is a native of the Duke of York's Island, in the South Pacific Ocean, and is undoubtedly one of the most interesting of the whole genus. Its compact habit, its comparatively small dimensions, and the bright, glossy color of its beautifully tasseled fronds render it a most welcome addition to a group of ferns naturally rich in decorative plants. Its curiously and irregularly pinnate fronds are borne on slender stalks, terete toward the base, and covered with reddish brown, downy scales, instead of being produced loosely, as in most other Nephrolepises; these are densily crowded, and the outcome of closely clustered crowns. They measure from 15 inches to 18 inches long, and are terminated by very handsome massive crests, which vary in size according to the temperature in which the plant is grown. We have at different times heard complaints of these fronds being simply furcate, when the same plant, after being subjected to a greater amount of heat and moisture, produced fronds very heavily tasseled, and partaking of an elegant vase-shaped appearance. In fact, nothing short of the moist heat of a stove will induce it to show its characters in their best condition. The pinn, which are small, of different sizes, rounded and serrated at the edges, are produced in pairs, one overlying the other, and, curiously enough, those on the top are the largest. The pairs are sometimes opposite, but mostly alternate, distant toward the base, approximate higher up, and crowded and quite overlapping in the crested portion of the frond. This, being a thoroughly barren kind, can only be propagated by division of the crowns, an operation easily done at any time of the year, but most safely in early spring and by young plants produced from the rhizomes, which, however, are produced much more sparingly than in any other species. It is also one of the best adapted for pot or pan culture, its somewhat upright habit making it less suitable for baskets, brackets, and wall covering than other species. Stove.—The Garden.



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FORMATION OF SUGAR.

A paper on "The Formation of Sugar in the Sugar-cane" was recently read by M. Aim Girard before the Paris Academy of Sciences. By comparative investigations of the amount of cane sugar and grape sugar in different parts of the sugar-cane in the afternoon and before sunrise, the author has found that only in the substance of the leaves does this quantity vary, and that the quantity of cane sugar sinks during the night to one-half, while the quantity of reducing sugar remains almost unaltered. He finds further that the quantity of sugar-cane in the leaves increases with the illumination, on very bright days reaching nearly one per cent., considerably less on dull ones, and in either case diminishing during the night by one-half. From this the author concludes that the formation of saccharose from glucose takes place entirely in the leaves under the influence of sunlight, and that the saccharose thereupon ascends the cane through the petioles, etc., and collects there.

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