Of the 2500 to 3500 calories of energy required to keep a man going for a day the best source of supply is the carbohydrates, that is, the sugars and starches. The fats are more concentrated but are more expensive and less easily assimilable. The proteins are also more expensive and their decomposition products are more apt to clog up the system. Common sugar is almost an ideal food. Cheap, clean, white, portable, imperishable, unadulterated, pleasant-tasting, germ-free, highly nutritious, completely soluble, altogether digestible, easily assimilable, requires no cooking and leaves no residue. Its only fault is its perfection. It is so pure that a man cannot live on it. Four square lumps give one hundred calories of energy. But twenty-five or thirty-five times that amount would not constitute a day's ration, in fact one would ultimately starve on such fare. It would be like supplying an army with an abundance of powder but neglecting to provide any bullets, clothing or food. To make sugar the sole food is impossible. To make it the main food is unwise. It is quite proper for man to separate out the distinct ingredients of natural products—to extract the butter from the milk, the casein from the cheese, the sugar from the cane—but he must not forget to combine them again at each meal with the other essential foodstuffs in their proper proportion.



Sugar is not a synthetic product and the business of the chemist has been merely to extract and purify it. But this is not so simple as it seems and every sugar factory has had to have its chemist. He has analyzed every mother beet for a hundred years. He has watched every step of the process from the cane to the crystal lest the sucrose should invert to the less sweet and non-crystallizable glucose. He has tested with polarized light every shipment of sugar that has passed through the custom house, much to the mystification of congressmen who have often wondered at the money and argumentation expended in a tariff discussion over the question of the precise angle of rotation of the plane of vibration of infinitesimal waves in a hypothetical ether.

The reason for this painstaking is that there are dozens of different sugars, so much alike that they are difficult to separate. They are all composed of the same three elements, C, H and O, and often in the same proportion. Sometimes two sugars differ only in that one has a right-handed and the other a left-handed twist to its molecule. They bear the same resemblance to one another as the two gloves of a pair. Cane sugar and beet sugar are when completely purified the same substance, that is, sucrose, C_{12}H_{22}O_{11}. The brown and straw-colored sugars, which our forefathers used and which we took to using during the war, are essentially the same but have not been so completely freed from moisture and the coloring and flavoring matter of the cane juice. Maple sugar is mostly sucrose. So partly is honey. Candies are made chiefly of sucrose with the addition of glucose, gums or starch, to give them the necessary consistency and of such colors and flavors, natural or synthetic, as may be desired. Practically all candy, even the cheapest, is nowadays free from deleterious ingredients in the manufacture, though it is liable to become contaminated in the handling. In fact sugar is about the only food that is never adulterated. It would be hard to find anything cheaper to add to it that would not be easily detected. "Sanding the sugar," the crime of which grocers are generally accused, is the one they are least likely to be guilty of.

Besides the big family of sugars which are all more or less sweet, similar in structure and about equally nutritious, there are, very curiously, other chemical compounds of altogether different composition which taste like sugar but are not nutritious at all. One of these is a coal-tar derivative, discovered accidentally by an American student of chemistry, Ira Remsen, afterward president of Johns Hopkins University, and named by him "saccharin." This has the composition C_{6}H_{4}COSO_{2}NH, and as you may observe from the symbol it contains sulfur (S) and nitrogen (N) and the benzene ring (C_{6}H_{4}) that are not found in any of the sugars. It is several hundred times sweeter than sugar, though it has also a slightly bitter aftertaste. A minute quantity of it can therefore take the place of a large amount of sugar in syrups, candies and preserves, so because it lends itself readily to deception its use in food has been prohibited in the United States and other countries. But during the war, on account of the shortage of sugar, it came again into use. The European governments encouraged what they formerly tried to prevent, and it became customary in Germany or Italy to carry about a package of saccharin tablets in the pocket and drop one or two into the tea or coffee. Such reversals of administrative attitude are not uncommon. When the use of hops in beer was new it was prohibited by British law. But hops became customary nevertheless and now the law requires hops to be used in beer. When workingmen first wanted to form unions, laws were passed to prevent them. But now, in Australia for instance, the laws require workingmen to form unions. Governments naturally tend to a conservative reaction against anything new.

It is amusing to turn back to the pure food agitation of ten years ago and read the sensational articles in the newspapers about the poisonous nature of this dangerous drug, saccharin, in view of the fact that it is being used by millions of people in Europe in amounts greater than once seemed to upset the tender stomachs of the Washington "poison squads." But saccharin does not appear to be responsible for any fatalities yet, though people are said to be heartily sick of it. And well they may be, for it is not a substitute for sugar except to the sense of taste. Glucose may correctly be called a substitute for sucrose as margarin for butter, since they not only taste much the same but have about the same food value. But to serve saccharin in the place of sugar is like giving a rubber bone to a dog. It is reported from Europe that the constant use of saccharin gives one eventually a distaste for all sweets. This is quite likely, although it means the reversal within a few years of prehistoric food habits. Mankind has always associated sweetness with food value, for there are few sweet things found in nature except the sugars. We think we eat sugar because it is sweet. But we do not. We eat it because it is good for us. The reason it tastes sweet to us is because it is good for us. So man makes a virtue out of necessity, a pleasure out of duty, which is the essence of ethics.

In the ancient days of Ind the great Raja Trishanku possessed an earthly paradise that had been constructed for his delectation by a magician. Therein grew all manner of beautiful flowers, savory herbs and delicious fruits such as had never been known before outside heaven. Of them all the Raja and his harems liked none better than the reed from which they could suck honey. But Indra, being a jealous god, was wroth when he looked down and beheld mere mortals enjoying such delights. So he willed the destruction of the enchanted garden. With drought and tempest it was devastated, with fire and hail, until not a leaf was left of its luxuriant vegetation and the ground was bare as a threshing floor. But the roots of the sugar cane are not destroyed though the stalk be cut down; so when men ventured to enter the desert where once had been this garden of Eden, they found the cane had grown up again and they carried away cuttings of it and cultivated it in their gardens. Thus it happened that the nectar of the gods descended first to monarchs and their favorites, then was spread among the people and carried abroad to other lands until now any child with a penny in his hand may buy of the best of it. So it has been with many things. So may it be with all things.



X

WHAT COMES FROM CORN

The discovery of America dowered mankind with a world of new flora. The early explorers in their haste to gather up gold paid little attention to the more valuable products of field and forest, but in the course of centuries their usefulness has become universally recognized. The potato and tomato, which Europe at first considered as unfit for food or even as poisonous, have now become indispensable among all classes. New World drugs like quinine and cocaine have been adopted into every pharmacopeia. Cocoa is proving a rival of tea and coffee, and even the banana has made its appearance in European markets. Tobacco and chicle occupy the nostrils and jaws of a large part of the human race. Maize and rubber are become the common property of mankind, but still may be called American. The United States alone raises four-fifths of the corn and uses three-fourths of the caoutchouc of the world.

All flesh is grass. This may be taken in a dietary as well as a metaphorical sense. The graminaceae provide the greater part of the sustenance of man and beast; hay and cereals, wheat, oats, rye, barley, rice, sugar cane, sorghum and corn. From an American viewpoint the greatest of these, physically and financially, is corn. The corn crop of the United States for 1917, amounting to 3,159,000,000 bushels, brought in more money than the wheat, cotton, potato and rye crops all together.

When Columbus reached the West Indies he found the savages playing with rubber balls, smoking incense sticks of tobacco and eating cakes made of a new grain that they called mahiz. When Pizarro invaded Peru he found this same cereal used by the natives not only for food but also for making alcoholic liquor, in spite of the efforts of the Incas to enforce prohibition. When the Pilgrim Fathers penetrated into the woods back of Plymouth Harbor they discovered a cache of Indian corn. So throughout the three Americas, from Canada to Peru, corn was king and it has proved worthy to rank with the rival cereals of other continents, the wheat of Europe and the rice of Asia. But food habits are hard to change and for the most part the people of the Old World are still ignorant of the delights of hasty pudding and Indian pudding, of hoe-cake and hominy, of sweet corn and popcorn. I remember thirty years ago seeing on a London stand a heap of dejected popcorn balls labeled "Novel American Confection. Please Try One." But nobody complied with this pitiful appeal but me and I was sorry that I did. Americans used to respond with a shipload of corn whenever an appeal came from famine sufferers in Armenia, Russia, Ireland, India or Austria, but their generosity was chilled when they found that their gift was resented as an insult or as an attempt to poison the impoverished population, who declared that they would rather die than eat it—and some of them did. Our Department of Agriculture sent maize missionaries to Europe with farmers and millers as educators and expert cooks to serve free flapjacks and pones, but the propaganda made little impression and today Americans are urged to eat more of their own corn because the famished families of the war-stricken region will not touch it. Just so the beggars of Munich revolted at potato soup when the pioneer of American food chemists, Bumford, attempted to introduce this transatlantic dish.

But here we are not so much concerned with corn foods as we are with its manufactured products. If you split a kernel in two you will find that it consists of three parts: a hard and horny hull on the outside, a small oily and nitrogenous germ at the point, and a white body consisting mostly of starch. Each of these is worked up into various products, as may be seen from the accompanying table. The hull forms bran and may be mixed with the gluten as a cattle food. The corn steeped for several days with sulfurous acid is disintegrated and on being ground the germs are floated off, the gluten or nitrogenous portion washed out, the starch grains settled down and the residue pressed together as oil cake fodder. The refined oil from the germ is marketed as a table or cooking oil under the name of "Mazola" and comes into competition with olive, peanut and cottonseed oil in the making of vegetable substitutes for lard and butter. Inferior grades may be used for soaps or for glycerin and perhaps nitroglycerin. A bushel of corn yields a pound or more of oil. From the corn germ also is extracted a gum called "paragol" that forms an acceptable substitute for rubber in certain uses. The "red rubber" sponges and the eraser tips to pencils may be made of it and it can contribute some twenty per cent. to the synthetic soles of shoes.



Starch, which constitutes fifty-five per cent. of the corn kernel, can be converted into a variety of products for dietary and industrial uses. As found in corn, potatoes or any other vegetables starch consists of small, round, white, hard grains, tasteless, and insoluble in cold water. But hot water converts it into a soluble, sticky form which may serve for starching clothes or making cornstarch pudding. Carrying the process further with the aid of a little acid or other catalyst it takes up water and goes over into a sugar, dextrose, commonly called "glucose." Expressed in chemical shorthand this reaction is

C_{6}H_{10}O_{5} + H_{2}O —> C_{6}H_{12}O_{6} starch water dextrose

This reaction is carried out on forty million bushels of corn a year in the United States. The "starch milk," that is, the starch grains washed out from the disintegrated corn kernel by water, is digested in large pressure tanks under fifty pounds of steam with a few tenths of one per cent. of hydrochloric acid until the required degree of conversion is reached. Then the remaining acid is neutralized by caustic soda, and thereby converted into common salt, which in this small amount does not interfere but rather enhances the taste. The product is the commercial glucose or corn syrup, which may if desired be evaporated to a white powder. It is a mixture of three derivatives of starch in about this proportion:

Maltose 45 per cent. Dextrose 20 per cent. Dextrin 35 per cent.

There are also present three- or four-tenths of one per cent. salt and as much of the corn protein and a variable amount of water. It will be noticed that the glucose (dextrose), which gives name to the whole, is the least of the three ingredients.

Maltose, or malt sugar, has the same composition as cane sugar (C_{12}H_{22}O_{11}), but is not nearly so sweet. Dextrin, or starch paste, is not sweet at all. Dextrose or glucose is otherwise known; as grape sugar, for it is commonly found in grapes and other ripe fruits. It forms half of honey and it is one of the two products into which cane sugar splits up when we take it into the mouth. It is not so sweet as cane sugar and cannot be so readily crystallized, which, however, is not altogether a disadvantage.

The process of changing starch into dextrose that takes place in the great steam kettles of the glucose factory is essentially the same as that which takes place in the ripening of fruit and in the digestion of starch. A large part of our nutriment, therefore, consists of glucose either eaten as such in ripe fruits or produced in the mouth or stomach by the decomposition of the starch of unripe fruit, vegetables and cereals. Glucose may be regarded as a predigested food. In spite of this well-known fact we still sometimes read "poor food" articles in which glucose is denounced as a dangerous adulterant and even classed as a poison.

The other ingredients of commercial glucose, the maltose and dextrin, have of course the same food value as the dextrose, since they are made over into dextrose in the process of digestion. Whether the glucose syrup is fit to eat depends, like anything else, on how it is made. If, as was formerly sometimes the case, sulfuric acid was used to effect the conversion of the starch or sulfurous acid to bleach the glucose and these acids were not altogether eliminated, the product might be unwholesome or worse. Some years ago in England there was a mysterious epidemic of arsenical poisoning among beer drinkers. On tracing it back it was found that the beer had been made from glucose which had been made from sulfuric acid which had been made from sulfur which had been made from a batch of iron pyrites which contained a little arsenic. The replacement of sulfuric acid by hydrochloric has done away with that danger and the glucose now produced is pure.

The old recipe for home-made candy called for the addition of a little vinegar to the sugar syrup to prevent "graining." The purpose of the acid was of course to invert part of the cane sugar to glucose so as to keep it from crystallizing out again. The professional candy-maker now uses the corn glucose for that purpose, so if we accuse him of "adulteration" on that ground we must levy the same accusation against our grandmothers. The introduction of glucose into candy manufacture has not injured but greatly increased the sale of sugar for the same purpose. This is not an uncommon effect of scientific progress, for as we have observed, the introduction of synthetic perfumes has stimulated the production of odoriferous flowers and the price of butter has gone up with the introduction of margarin. So, too, there are more weavers employed and they get higher wages than in the days when they smashed up the first weaving machines, and the same is true of printers and typesetting machines. The popular animosity displayed toward any new achievement of applied science is never justified, for it benefits not only the world as a whole but usually even those interests with which it seems at first to conflict.

The chemist is an economizer. It is his special business to hunt up waste products and make them useful. He was, for instance, worried over the waste of the cores and skins and scraps that were being thrown away when apples were put up. Apple pulp contains pectin, which is what makes jelly jell, and berries and fruits that are short of it will refuse to "jell." But using these for their flavor he adds apple pulp for pectin and glucose for smoothness and sugar for sweetness and, if necessary, synthetic dyes for color, he is able to put on the market a variety of jellies, jams and marmalades at very low price. The same principle applies here as in the case of all compounded food products. If they are made in cleanly fashion, contain no harmful ingredients and are truthfully labeled there is no reason for objecting to them. But if the manufacturer goes so far as to put strawberry seeds—or hayseed—into his artificial "strawberry jam" I think that might properly be called adulteration, for it is imitating the imperfections of nature, and man ought to be too proud to do that.

The old-fashioned open kettle molasses consisted mostly of glucose and other invert sugars together with such cane sugar as could not be crystallized out. But when the vacuum pan was introduced the molasses was impoverished of its sweetness and beet sugar does not yield any molasses. So we now have in its place the corn syrups consisting of about 85 per cent. of glucose and 15 per cent. of sugar flavored with maple or vanillin or whatever we like. It is encouraging to see the bill boards proclaiming the virtues of "Karo" syrup and "Mazola" oil when only a few years ago the products of our national cereal were without honor in their own country.

Many other products besides foods are made from corn starch. Dextrin serves in place of the old "gum arabic" for the mucilage of our envelopes and stamps. Another form of dextrin sold as "Kordex" is used to hold together the sand of the cores of castings. After the casting has been made the scorched core can be shaken out. Glucose is used in place of sugar as a filler for cheap soaps and for leather.

Altogether more than a hundred different commercial products are now made from corn, not counting cob pipes. Every year the factories of the United States work up over 50,000,000 bushels of corn into 800,000,000 pounds of corn syrup, 600,000,000 pounds of starch, 230,000,000 pounds of corn sugar, 625,000,000 pounds of gluten feed, 90,000,000 pounds of oil and 90,000,000 pounds of oil cake.

Two million bushels of cobs are wasted every year in the United States. Can't something be made out of them? This is the question that is agitating the chemists of the Carbohydrate Laboratory of the Department of Agriculture at Washington. They have found it possible to work up the corn cobs into glucose and xylose by heating with acid. But glucose can be more cheaply obtained from other starchy or woody materials and they cannot find a market for the xylose. This is a sort of a sugar but only about half as sweet as that from cane. Who can invent a use for it! More promising is the discovery by this laboratory that by digesting the cobs with hot water there can be extracted about 30 per cent. of a gum suitable for bill posting and labeling.

Since the starches and sugars belong to the same class of compounds as the celluloses they also can be acted upon by nitric acid with the production of explosives like guncotton. Nitro-sugar has not come into common use, but nitro-starch is found to be one of safest of the high explosives. On account of the danger of decomposition and spontaneous explosion from the presence of foreign substances the materials in explosives must be of the purest possible. It was formerly thought that tapioca must be imported from Java for making nitro-starch. But during the war when shipping was short, the War Department found that it could be made better and cheaper from our home-grown corn starch. When the war closed the United States was making 1,720,000 pounds of nitro-starch a month for loading hand grenades. So, too, the Post Office Department discovered that it could use mucilage made of corn dextrin as well as that which used to be made from tapioca. This is progress in the right direction. It would be well to divert some of the energetic efforts now devoted to the increase of commerce to the discovery of ways of reducing the need for commerce by the development of home products. There is no merit in simply hauling things around the world.

In the last chapter we saw how dextrose or glucose could be converted by fermentation into alcohol. Since corn starch, as we have seen, can be converted into dextrose, it can serve as a source of alcohol. This was, in fact, one of the earliest misuses to which corn was put, and before the war put a stop to it 34,000,000 bushels went into the making of whiskey in the United States every year, not counting the moonshiners' output. But even though we left off drinking whiskey the distillers could still thrive. Mars is more thirsty than Bacchus. The output of whiskey, denatured for industrial purposes, is more than three times what is was before the war, and the price has risen from 30 cents a gallon to 67 cents. This may make it profitable to utilize sugars, starches and cellulose that formerly were out of the question. According to the calculations of the Forest Products Laboratory of Madison it costs from 37 to 44 cents a gallon to make alcohol from corn, but it may be made from sawdust at a cost of from 14 to 20 cents. This is not "wood alcohol" (that is, methyl alcohol, CH_{4}O) such as is made by the destructive distillation of wood, but genuine "grain alcohol" (ethyl alcohol, C_{2}H_{6}O), such as is made by the fermentation of glucose or other sugar. The first step in the process is to digest the sawdust or chips with dilute sulfuric acid under heat and pressure. This converts the cellulose (wood fiber) in large part into glucose ("corn sugar") which may be extracted by hot water in a diffusion battery as in extracting the sugar from beet chips. This glucose solution may then be fermented by yeast and the resulting alcohol distilled off. The process is perfectly practicable but has yet to be proved profitable. But the sulfite liquors of the paper mills are being worked up successfully into industrial alcohol.

The rapidly approaching exhaustion of our oil fields which the war has accelerated leads us to look around to see what we can get to take the place of gasoline. One of the most promising of the suggested substitutes is alcohol. The United States is exceptionally rich in mineral oil, but some countries, for instance England, Germany, France and Australia, have little or none. The Australian Advisory Council of Science, called to consider the problem, recommends alcohol for stationary engines and motor cars. Alcohol has the disadvantage of being less volatile than gasoline so it is hard to start up the engine from the cold. But the lower volatility and ignition point of alcohol are an advantage in that it can be put under a pressure of 150 pounds to the square inch. A pound of gasoline contains fifty per cent. more potential energy than a pound of alcohol, but since the alcohol vapor can be put under twice the compression of the gasoline and requires only one-third the amount of air, the thermal efficiency of an alcohol engine may be fifty per cent. higher than that of a gasoline engine. Alcohol also has several other conveniences that can count in its favor. In the case of incomplete combustion the cylinders are less likely to be clogged with carbon and the escaping gases do not have the offensive odor of the gasoline smoke. Alcohol does not ignite so easily as gasoline and the fire is more readily put out, for water thrown upon blazing alcohol dilutes it and puts out the flame while gasoline floats on water and the fire is spread by it. It is possible to increase the inflammability of alcohol by mixing with it some hydrocarbon such as gasoline, benzene or acetylene. In the Taylor-White process the vapor from low-grade alcohol containing 17 per cent. water is passed over calcium carbide. This takes out the water and adds acetylene gas, making a suitable mixture for an internal combustion engine.

Alcohol can be made from anything of a starchy, sugary or woody nature, that is, from the main substance of all vegetation. If we start with wood (cellulose) we convert it first into sugar (glucose) and, of course, we could stop here and use it for food instead of carrying it on into alcohol. This provides one factor of our food, the carbohydrate, but by growing the yeast plants on glucose and feeding them with nitrates made from the air we can get the protein and fat. So it is quite possible to live on sawdust, although it would be too expensive a diet for anybody but a millionaire, and he would not enjoy it. Glucose has been made from formaldehyde and this in turn made from carbon, hydrogen and oxygen, so the synthetic production of food from the elements is not such an absurdity as it was thought when Berthelot suggested it half a century ago.

The first step in the making of alcohol is to change the starch over into sugar. This transformation is effected in the natural course of sprouting by which the insoluble starch stored up in the seed is converted into the soluble glucose for the sap of the growing plant. This malting process is that mainly made use of in the production of alcohol from grain. But there are other ways of effecting the change. It may be done by heating with acid as we have seen, or according to a method now being developed the final conversion may be accomplished by mold instead of malt. In applying this method, known as the amylo process, to corn, the meal is mixed with twice its weight of water, acidified with hydrochloric acid and steamed. The mash is then cooled down somewhat, diluted with sterilized water and innoculated with the mucor filaments. As the mash molds the starch is gradually changed over to glucose and if this is the product desired the process may be stopped at this point. But if alcohol is wanted yeast is added to ferment the sugar. By keeping it alkaline and treating with the proper bacteria a high yield of glycerin can be obtained.

In the fermentation process for making alcoholic liquors a little glycerin is produced as a by-product. Glycerin, otherwise called glycerol, is intermediate between sugar and alcohol. Its molecule contains three carbon atoms, while glucose has six and alcohol two. It is possible to increase the yield of glycerin if desired by varying the form of fermentation. This was desired most earnestly in Germany during the war, for the British blockade shut off the importation of the fats and oils from which the Germans extracted the glycerin for their nitroglycerin. Under pressure of this necessity they worked out a process of getting glycerin in quantity from sugar and, news of this being brought to this country by Dr. Alonzo Taylor, the United States Treasury Department set up a special laboratory to work out this problem. John R. Eoff and other chemists working in this laboratory succeeded in getting a yield of twenty per cent. of glycerin by fermenting black strap molasses or other syrup with California wine yeast. During the fermentation it is necessary to neutralize the acetic acid formed with sodium or calcium carbonate. It was estimated that glycerin could be made from waste sugars at about a quarter of its war-time cost, but it is doubtful whether the process would be profitable at normal prices.

We can, if we like, dispense with either yeast or bacteria in the production of glycerin. Glucose syrup suspended in oil under steam pressure with finely divided nickel as a catalyst and treated with nascent hydrogen will take up the hydrogen and be converted into glycerin. But the yield is poor and the process expensive.

Food serves substantially the same purpose in the body as fuel in the engine. It provides the energy for work. The carbohydrates, that is the sugars, starches and celluloses, can all be used as fuels and can all—even, as we have seen, the cellulose—be used as foods. The final products, water and carbon dioxide, are in both cases the same and necessarily therefore the amount of energy produced is the same in the body as in the engine. Corn is a good example of the equivalence of the two sources of energy. There are few better foods and no better fuels. I can remember the good old days in Kansas when we had corn to burn. It was both an economy and a luxury, for—at ten cents a bushel—it was cheaper than coal or wood and preferable to either at any price. The long yellow ears, each wrapped in its own kindling, could be handled without crocking the fingers. Each kernel as it crackled sent out a blazing jet of oil and the cobs left a fine bed of coals for the corn popper to be shaken over. Driftwood and the pyrotechnic fuel they make now by soaking sticks in strontium and copper salts cannot compare with the old-fashioned corn-fed fire in beauty and the power of evoking visions. Doubtless such luxury would be condemned as wicked nowadays, but those who have known the calorific value of corn would find it hard to abandon it altogether, and I fancy that the Western farmer's wife, when she has an extra batch of baking to do, will still steal a few ears from the crib.



XI

SOLIDIFIED SUNSHINE

All life and all that life accomplishes depend upon the supply of solar energy stored in the form of food. The chief sources of this vital energy are the fats and the sugars. The former contain two and a quarter times the potential energy of the latter. Both, when completely purified, consist of nothing but carbon, hydrogen and oxygen; elements that are to be found freely everywhere in air and water. So when the sunny southland exports fats and oils, starches and sugar, it is then sending away nothing material but what comes back to it in the next wind. What it is sending to the regions of more slanting sunshine is merely some of the surplus of the radiant energy it has received so abundantly, compacted for convenience into a portable and edible form.

In previous chapters I have dealt with some of the uses of cotton, its employment for cloth, for paper, for artificial fibers, for explosives, and for plastics. But I have ignored the thing that cotton is attached to and for which, in the economy of nature, the fibers are formed; that is, the seed. It is as though I had described the aeroplane and ignored the aviator whom it was designed to carry. But in this neglect I am but following the example of the human race, which for three thousand years used the fiber but made no use of the seed except to plant the next crop.

Just as mankind is now divided into the two great classes, the wheat-eaters and the rice-eaters, so the ancient world was divided into the wool-wearers and the cotton-wearers. The people of India wore cotton; the Europeans wore wool. When the Greeks under Alexander fought their way to the Far East they were surprised to find wool growing on trees. Later travelers returning from Cathay told of the same marvel and travelers who stayed at home and wrote about what they had not seen, like Sir John Maundeville, misunderstood these reports and elaborated a legend of a tree that bore live lambs as fruit. Here, for instance, is how a French poetical botanist, Delacroix, described it in 1791, as translated from his Latin verse:

Upon a stalk is fixed a living brute, A rooted plant bears quadruped for fruit; It has a fleece, nor does it want for eyes, And from its brows two wooly horns arise. The rude and simple country people say It is an animal that sleeps by day And wakes at night, though rooted to the ground, To feed on grass within its reach around.

But modern commerce broke down the barrier between East and West. A new cotton country, the best in the world, was discovered in America. Cotton invaded England and after a hard fight, with fists as well as finance, wool was beaten in its chief stronghold. Cotton became King and the wool-sack in the House of Lords lost its symbolic significance.

Still two-thirds of the cotton crop, the seed, was wasted and it is only within the last fifty years that methods of using it have been developed to any extent.

The cotton crop of the United States for 1917 amounted to about 11,000,000 bales of 500 pounds each. When the Great War broke out and no cotton could be exported to Germany and little to England the South was in despair, for cotton went down to five or six cents a pound. The national Government, regardless of states' rights, was called upon for aid and everybody was besought to "buy a bale." Those who responded to this patriotic appeal were well rewarded, for cotton rose as the war went on and sold at twenty-nine cents a pound.



But the chemist has added some $150,000,000 a year to the value of the crop by discovering ways of utilizing the cottonseed that used to be thrown away or burned as fuel. The genealogical table of the progeny of the cottonseed herewith printed will give some idea of their variety. If you will examine a cottonseed you will see first that there is a fine fuzz of cotton fiber sticking to it. These linters can be removed by machinery and used for any purpose where length of fiber is not essential. For instance, they may be nitrated as described in previous articles and used for making smokeless powder or celluloid.

On cutting open the seed you will observe that it consists of an oily, mealy kernel encased in a thin brown hull. The hulls, amounting to 700 or 900 pounds in a ton of seed, were formerly burned. Now, however, they bring from $4 to $10 a ton because they can be ground up into cattle-feed or paper stock or used as fertilizer.

The kernel of the cottonseed on being pressed yields a yellow oil and leaves a mealy cake. This last, mixed with the hulls, makes a good fodder for fattening cattle. Also, adding twenty-five per cent. of the refined cottonseed meal to our war bread made it more nutritious and no less palatable. Cottonseed meal contains about forty per cent. of protein and is therefore a highly concentrated and very valuable feeding stuff. Before the war we were exporting nearly half a million tons of cottonseed meal to Europe, chiefly to Germany and Denmark, where it is used for dairy cows. The British yeoman, his country's pride, has not yet been won over to the use of any such newfangled fodder and consequently the British manufacturer could not compete with his continental rivals in the seed-crushing business, for he could not dispose of his meal-cake by-product as did they.



Let us now turn to the most valuable of the cottonseed products, the oil. The seed contains about twenty per cent. of oil, most of which can be squeezed out of the hot seeds by hydraulic pressure. It comes out as a red liquid of a disagreeable odor. This is decolorized, deodorized and otherwise purified in various ways: by treatment with alkalies or acids, by blowing air and steam through it, by shaking up with fuller's earth, by settling and filtering. The refined product is a yellow oil, suitable for table use. Formerly, on account of the popular prejudice against any novel food products, it used to masquerade as olive oil. Now, however, it boldly competes with its ancient rival in the lands of the olive tree and America ships some 700,000 barrels of cottonseed oil a year to the Mediterranean. The Turkish Government tried to check the spread of cottonseed oil by calling it an adulterant and prohibiting its mixture with olive oil. The result was that the sale of Turkish olive oil fell off because people found its flavor too strong when undiluted. Italy imports cottonseed oil and exports her olive oil. Denmark imports cottonseed meal and margarine and exports her butter.

Northern nations are accustomed to hard fats and do not take to oils for cooking or table use as do the southerners. Butter and lard are preferred to olive oil and ghee. But this does not rule out cottonseed. It can be combined with the hard fats of animal or vegetable origin in margarine or it may itself be hardened by hydrogen.

To understand this interesting reaction which is profoundly affecting international relations it will be necessary to dip into the chemistry of the subject. Here are the symbols of the chief ingredients of the fats and oils. Please look at them.

Linoleic acid C_{18}H_{32}O_{2} Oleic acid C_{18}H_{34}O_{2} Stearic acid C_{18}H_{36}O_{2}

Don't skip these because you have not studied chemistry. That's why I am giving them to you. If you had studied chemistry you would know them without my telling. Just examine them and you will discover the secret. You will see that all three are composed of the same elements, carbon, hydrogen, and oxygen. Notice next the number of atoms in each element as indicated by the little low figures on the right of each letter. You observe that all three contain the same number of atoms of carbon and oxygen but differ in the amount of hydrogen. This trifling difference in composition makes a great difference in behavior. The less the hydrogen the lower the melting point. Or to say the same thing in other words, fatty substances low in hydrogen are apt to be liquids and those with a full complement of hydrogen atoms are apt to be solids at the ordinary temperature of the air. It is common to call the former "oils" and the latter "fats," but that implies too great a dissimilarity, for the distinction depends on whether we are living in the tropics or the arctic. It is better, therefore, to lump them all together and call them "soft fats" and "hard fats," respectively.

Fats of the third order, the stearic group, are called "saturated" because they have taken up all the hydrogen they can hold. Fats of the other two groups are called "unsaturated." The first, which have the least hydrogen, are the most eager for more. If hydrogen is not handy they will take up other things, for instance oxygen. Linseed oil, which consists largely, as the name implies, of linoleic acid, will absorb oxygen on exposure to the air and become hard. That is why it is used in painting. Such oils are called "drying" oils, although the hardening process is not really drying, since they contain no water, but is oxidation. The "semi-drying oils," those that will harden somewhat on exposure to the air, include the oils of cottonseed, corn, sesame, soy bean and castor bean. Olive oil and peanut oil are "non-drying" and contain oleic compounds (olein). The hard fats, such as stearin, palmitin and margarin, are mostly of animal origin, tallow and lard, though coconut and palm oil contain a large proportion of such saturated compounds.

Though the chemist talks of the fatty "acids," nobody else would call them so because they are not sour. But they do behave like the acids in forming salts with bases. The alkali salts of the fatty acids are known to us as soaps. In the natural fats they exist not as free acids but as salts of an organic base, glycerin, as I explained in a previous chapter. The natural fats and oils consist of complex mixtures of the glycerin compounds of these acids (known as olein, stearin, etc.), as well as various others of a similar sort. If you will set a bottle of salad oil in the ice-box you will see it separate into two parts. The white, crystalline solid that separates out is largely stearin. The part that remains liquid is largely olein. You might separate them by filtering it cold and if then you tried to sell the two products you would find that the hard fat would bring a higher price than the oil, either for food or soap. If you tried to keep them you would find that the hard fat kept neutral and "sweet" longer than the other. You may remember that the perfumes (as well as their odorous opposites) were mostly unsaturated compounds. So we find that it is the free and unsaturated fatty acids that cause butter and oil to become rank and rancid.

Obviously, then, we could make money if we could turn soft, unsaturated fats like olein into hard, saturated fats like stearin. Referring to the symbols we see that all that is needed to effect the change is to get the former to unite with hydrogen. This requires a little coaxing. The coaxer is called a catalyst. A catalyst, as I have previously explained, is a substance that by its mere presence causes the union of two other substances that might otherwise remain separate. For that reason the catalyst is referred to as "a chemical parson." Finely divided metals have a strong catalytic action. Platinum sponge is excellent but too expensive. So in this case nickel is used. A nickel salt mixed with charcoal or pumice is reduced to the metallic state by heating in a current of hydrogen. Then it is dropped into the tank of oil and hydrogen gas is blown through. The hydrogen may be obtained by splitting water into its two components, hydrogen and oxygen, by means of the electrical current, or by passing steam over spongy iron which takes out the oxygen. The stream of hydrogen blown through the hot oil converts the linoleic acid to oleic and then the oleic into stearic. If you figured up the weights from the symbols given above you would find that it takes about one pound of hydrogen to convert a hundred pounds of olein to stearin and the cost is only about one cent a pound. The nickel is unchanged and is easily separated. A trace of nickel may remain in the product, but as it is very much less than the amount dissolved when food is cooked in nickel-plated vessels it cannot be regarded as harmful.

Even more unsaturated fats may be hydrogenated. Fish oil has hitherto been almost unusable because of its powerful and persistent odor. This is chiefly due to a fatty acid which properly bears the uneuphonious name of clupanodonic acid and has the composition of C{18}H{28}O{2}. By comparing this with the symbol of the odorless stearic acid, C{18}H{36}O{2}, you will see that all the rank fish oil lacks to make it respectable is eight hydrogen atoms. A Japanese chemist, Tsujimoto, has discovered how to add them and now the reformed fish oil under the names of "talgol" and "candelite" serves for lubricant and even enters higher circles as a soap or food.

This process of hardening fats by hydrogenation resulted from the experiments of a French chemist, Professor Sabatier of Toulouse, in the last years of the last century, but, as in many other cases, the Germans were the first to take it up and profit by it. Before the war the copra or coconut oil from the British Asiatic colonies of India, Ceylon and Malaya went to Germany at the rate of $15,000,000 a year. The palm kernels grown in British West Africa were shipped, not to Liverpool, but to Hamburg, $19,000,000 worth annually. Here the oil was pressed out and used for margarin and the residual cake used for feeding cows produced butter or for feeding hogs produced lard. Half of the copra raised in the British possessions was sent to Germany and half of the oil from it was resold to the British margarin candle and soap makers at a handsome profit. The British chemists were not blind to this, but they could do nothing, first because the English politician was wedded to free trade, second, because the English farmer would not use oil cake for his stock. France was in a similar situation. Marseilles produced 15,500,000 gallons of oil from peanuts grown largely in the French African colonies—but shipped the oil-cake on to Hamburg. Meanwhile the Germans, in pursuit of their policy of attaining economic independence, were striving to develop their own tropical territory. The subjects of King George who because they had the misfortune to live in India were excluded from the British South African dominions or mistreated when they did come, were invited to come to German East Africa and set to raising peanuts in rivalry to French Senegal and British Coromandel. Before the war Germany got half of the Egyptian cottonseed and half of the Philippine copra. That is one of the reasons why German warships tried to check Dewey at Manila in 1898 and German troops tried to conquer Egypt in 1915.

But the tide of war set the other way and the German plantations of palmnuts and peanuts in Africa have come into British possession and now the British Government is starting an educational campaign to teach their farmers to feed oil cake like the Germans and their people to eat peanuts like the Americans.

The Germans shut off from the tropical fats supply were hard up for food and for soap, for lubricants and for munitions. Every person was given a fat card that reduced his weekly allowance to the minimum. Millers were required to remove the germs from their cereals and deliver them to the war department. Children were set to gathering horse-chestnuts, elderberries, linden-balls, grape seeds, cherry stones and sunflower heads, for these contain from six to twenty per cent. of oil. Even the blue-bottle fly—hitherto an idle creature for whom Beelzebub found mischief—was conscripted into the national service and set to laying eggs by the billion on fish refuse. Within a few days there is a crop of larvae which, to quote the "Chemische Zentralblatt," yields forty-five grams per kilogram of a yellow oil. This product, we should hope, is used for axle-grease and nitroglycerin, although properly purified it would be as nutritious as any other—to one who has no imagination. Driven to such straits Germany would have given a good deal for one of those tropical islands that we are so careless about.

It might have been supposed that since the United States possessed the best land in the world for the production of cottonseed, coconuts, peanuts, and corn that it would have led all other countries in the utilization of vegetable oils for food. That this country has not so used its advantage is due to the fact that the new products have not merely had to overcome popular conservatism, ignorance and prejudice—hard things to fight in any case—but have been deliberately checked and hampered by the state and national governments in defense of vested interests. The farmer vote is a power that no politician likes to defy and the dairy business in every state was thoroughly organized. In New York the oleomargarin industry that in 1879 was turning out products valued at more than $5,000,000 a year was completely crushed out by state legislation.[2] The output of the United States, which in 1902 had risen to 126,000,000 pounds, was cut down to 43,000,000 pounds in 1909 by federal legislation. According to the disingenuous custom of American lawmakers the Act of 1902 was passed through Congress as a "revenue measure," although it meant a loss to the Government of more than three million dollars a year over what might be produced by a straight two cents a pound tax. A wholesale dealer in oleomargarin was made to pay a higher license than a wholesale liquor dealer. The federal law put a tax of ten cents a pound on yellow oleomargarin and a quarter of a cent a pound on the uncolored. But people—doubtless from pure prejudice—prefer a yellow spread for their bread, so the economical housewife has to work over her oleomargarin with the annatto which is given to her when she buys a package or, if the law prohibits this, which she is permitted to steal from an open box on the grocer's counter. A plausible pretext for such legislation is afforded by the fact that the butter substitutes are so much like butter that they cannot be easily distinguished from it unless the use of annatto is permitted to butter and prohibited to its competitors. Fradulent sales of substitutes of any kind ought to be prevented, but the recent pure food legislation in America has shown that it is possible to secure truthful labeling without resorting to such drastic measures. In Europe the laws against substitution were very strict, but not devised to restrict the industry. Consequently the margarin output of Germany doubled in the five years preceding the war and the output of England tripled. In Denmark the consumption of margarin rose from 8.8 pounds per capita in 1890 to 32.6 pounds in 1912. Yet the butter business, Denmark's pride, was not injured, and Germany and England imported more butter than ever before. Now that the price of butter in America has gone over the seventy-five cent mark Congress may conclude that it no longer needs to be protected against competition.

The "compound lards" or "lard compounds," consisting usually of cottonseed oil and oleo-stearin, although the latter may now be replaced by hardened oil, met with the same popular prejudice and attempted legislative interference, but succeeded more easily in coming into common use under such names as "Cottosuet," "Kream Krisp," "Kuxit," "Korno," "Cottolene" and "Crisco."

Oleomargarin, now generally abbreviated to margarin, originated, like many other inventions, in military necessity. The French Government in 1869 offered a prize for a butter substitute for the army that should be cheaper and better than butter in that it did not spoil so easily. The prize was won by a French chemist, Mege-Mouries, who found that by chilling beef fat the solid stearin could be separated from an oil (oleo) which was the substantially same as that in milk and hence in butter. Neutral lard acts the same.

This discovery of how to separate the hard and soft fats was followed by improved methods for purifying them and later by the process for converting the soft into the hard fats by hydrogenation. The net result was to put into the hands of the chemist the ability to draw his materials at will from any land and from the vegetable and animal kingdoms and to combine them as he will to make new fat foods for every use; hard for summer, soft for winter; solid for the northerners and liquid for the southerners; white, yellow or any other color, and flavored to suit the taste. The Hindu can eat no fat from the sacred cow; the Mohammedan and the Jew can eat no fat from the abhorred pig; the vegetarian will touch neither; other people will take both. No matter, all can be accommodated.

All the fats and oils, though they consist of scores of different compounds, have practically the same food value when freed from the extraneous matter that gives them their characteristic flavors. They are all practically tasteless and colorless. The various vegetable and animal oils and fats have about the same digestibility, 98 per cent.,[3] and are all ordinarily completely utilized in the body, supplying it with two and a quarter times as much energy as any other food.

It does not follow, however, that there is no difference in the products. The margarin men accuse butter of harboring tuberculosis germs from which their product, because it has been heated or is made from vegetable fats, is free. The butter men retort that margarin is lacking in vitamines, those mysterious substances which in minute amounts are necessary for life and especially for growth. Both the claim and the objection lose a large part of their force where the margarin, as is customarily the case, is mixed with butter or churned up with milk to give it the familiar flavor. But the difficulty can be easily overcome. The milk used for either butter or margarin should be free or freed from disease germs. If margarin is altogether substituted for butter, the necessary vitamines may be sufficiently provided by milk, eggs and greens.

Owing to these new processes all the fatty substances of all lands have been brought into competition with each other. In such a contest the vegetable is likely to beat the animal and the southern to win over the northern zones. In Europe before the war the proportion of the various ingredients used to make butter substitutes was as follows:

AVERAGE COMPOSITION OF EUROPEAN MARGARIN

Per Cent. Animal hard fats 25 Vegetable hard fats 35 Copra 29 Palm-kernel 6 Vegetable soft fats 26 Cottonseed 13 Peanut 6 Sesame 6 Soya-bean 1 Water, milk, salt 14 _ 100

This is not the composition of any particular brand but the average of them all. The use of a certain amount of the oil of the sesame seed is required by the laws of Germany and Denmark because it can be easily detected by a chemical color test and so serves to prevent the margarin containing it from being sold as butter. "Open sesame!" is the password to these markets. Remembering that margarin originally was made up entirely of animal fats, soft and hard, we can see from the above figures how rapidly they are being displaced by the vegetable fats. The cottonseed and peanut oils have replaced the original oleo oil and the tropical oils from the coconut (copra) and African palm are crowding out the animal hard fats. Since now we can harden at will any of the vegetable oils it is possible to get along altogether without animal fats. Such vegetable margarins were originally prepared for sale in India, but proved unexpectedly popular in Europe, and are now being introduced into America. They are sold under various trade names suggesting their origin, such as "palmira," "palmona," "milkonut," "cocose," "coconut oleomargarin" and "nucoa nut margarin." The last named is stated to be made of coconut oil (for the hard fat) and peanut oil (for the soft fat), churned up with a culture of pasteurized milk (to impart the butter flavor). The law requires such a product to be branded "oleomargarine" although it is not. Such cases of compulsory mislabeling are not rare. You remember the "Pigs is Pigs" story.

Peanut butter has won its way into the American menu without any camouflage whatever, and as a salad oil it is almost equally frank about its lowly origin. This nut, which grows on a vine instead of a tree, and is dug from the ground like potatoes instead of being picked with a pole, goes by various names according to locality, peanuts, ground-nuts, monkey-nuts, arachides and goobers. As it takes the place of cotton oil in some of its products so it takes its place in the fields and oilmills of Texas left vacant by the bollweevil. The once despised peanut added some $56,000,000 to the wealth of the South in 1916. The peanut is rich in the richest of foods, some 50 per cent. of oil and 30 per cent. of protein. The latter can be worked up into meat substitutes that will make the vegetarian cease to envy his omnivorous neighbor. Thanks largely to the chemist who has opened these new fields of usefulness, the peanut-raiser got $1.25 a bushel in 1917 instead of the 30 cents that he got four years before.

It would be impossible to enumerate all the available sources of vegetable oils, for all seeds and nuts contain more or less fatty matter and as we become more economical we shall utilize of what we now throw away. The germ of the corn kernel, once discarded in the manufacture of starch, now yields a popular table oil. From tomato seeds, one of the waste products of the canning factory, can be extracted 22 per cent. of an edible oil. Oats contain 7 per cent. of oil. From rape seed the Japanese get 20,000 tons of oil a year. To the sources previously mentioned may be added pumpkin seeds, poppy seeds, raspberry seeds, tobacco seeds, cockleburs, hazelnuts, walnuts, beechnuts and acorns.

The oil-bearing seeds of the tropics are innumerable and will become increasingly essential to the inhabitants of northern lands. It was the realization of this that brought on the struggle of the great powers for the possession of tropical territory which, for years before, they did not think worth while raising a flag over. No country in the future can consider itself safe unless it has secure access to such sources. We had a sharp lesson in this during the war. Palm oil, it seems, is necessary for the manufacture of tinplate, an industry that was built up in the United States by the McKinley tariff. The British possessions in West Africa were the chief source of palm oil and the Germans had the handling of it. During the war the British Government assumed control of the palm oil products of the British and German colonies and prohibited their export to other countries than England. Americans protested and beseeched, but in vain. The British held, quite correctly, that they needed all the oil they could get for food and lubrication and nitroglycerin. But the British also needed canned meat from America for their soldiers and when it was at length brought to their attention that the packers could not ship meat unless they had cans and that cans could not be made without tin and that tin could not be made without palm oil the British Government consented to let us buy a little of their palm oil. The lesson is that of Voltaire's story, "Candide," "Let us cultivate our own garden"—and plant a few palm trees in it—also rubber trees, but that is another story.

The international struggle for oil led to the partition of the Pacific as the struggle for rubber led to the partition of Africa. Theodor Weber, as Stevenson says, "harried the Samoans" to get copra much as King Leopold of Belgium harried the Congoese to get caoutchouc. It was Weber who first fully realized that the South Sea islands, formerly given over to cannibals, pirates and missionaries, might be made immensely valuable through the cultivation of the coconut palms. When the ripe coconut is split open and exposed to the sun the meat dries up and shrivels and in this form, called "copra," it can be cut out and shipped to the factory where the oil is extracted and refined. Weber while German Consul in Samoa was also manager of what was locally known as "the long-handled concern" (Deutsche Handels und Plantagen Gesellschaft der Suedsee Inseln zu Hamburg), a pioneer commercial and semi-official corporation that played a part in the Pacific somewhat like the British Hudson Bay Company in Canada or East India Company in Hindustan. Through the agency of this corporation on the start Germany acquired a virtual monopoly of the transportation and refining of coconut oil and would have become the dominant power in the Pacific if she had not been checked by force of arms. In Apia Bay in 1889 and again in Manila Bay in 1898 an American fleet faced a German fleet ready for action while a British warship lay between. So we rescued the Philippines and Samoa from German rule and in 1914 German power was eliminated from the Pacific. During the ten years before the war, the production of copra in the German islands more than doubled and this was only the beginning of the business. Now these islands have been divided up among Australia, New Zealand and Japan, and these countries are planning to take care of the copra.

But although we get no extension of territory from the war we still have the Philippines and some of the Samoan Islands, and these are capable of great development. From her share of the Samoan Islands Germany got a million dollars' worth of copra and we might get more from ours. The Philippines now lead the world in the production of copra, but Java is a close second and Ceylon not far behind. If we do not look out we will be beaten both by the Dutch and the British, for they are undertaking the cultivation of the coconut on a larger scale and in a more systematic way. According to an official bulletin of the Philippine Government a coconut plantation should bring in "dividends ranging from 10 to 75 per cent. from the tenth to the hundredth year." And this being printed in 1913 figured the price of copra at 3-1/2 cents, whereas it brought 4-1/2 cents in 1918, so the prospect is still more encouraging. The copra is half fat and can be cheaply shipped to America, where it can be crushed in the southern oilmills when they are not busy on cottonseed or peanuts. But even this cost of transportation can be reduced by extracting the oil in the islands and shipping it in bulk like petroleum in tank steamers.

In the year ending June, 1918, the United States imported from the Philippines 155,000,000 pounds of coconut oil worth $18,000,000 and 220,000,000 pounds of copra worth $10,000,000. But this was about half our total importations; the rest of it we had to get from foreign countries. Panama palms may give us a little relief from this dependence on foreign sources. In 1917 we imported 19,000,000 whole coconuts from Panama valued at $700,000.



A new form of fat that has rapidly come into our market is the oil of the soya or soy bean. In 1918 we imported over 300,000,000 pounds of soy-bean oil, mostly from Manchuria. The oil is used in manufacture of substitutes for butter, lard, cheese, milk and cream, as well as for soap and paint. The soy-bean can be raised in the United States wherever corn can be grown and provides provender for man and beast. The soy meal left after the extraction of the oil makes a good cattle food and the fermented juice affords the shoya sauce made familiar to us through the popularity of the chop-suey restaurants.

As meat and dairy products become scarcer and dearer we shall become increasingly dependent upon the vegetable fats. We should therefore devise means of saving what we now throw away, raise as much as we can under our own flag, keep open avenues for our foreign supply and encourage our cooks to make use of the new products invented by our chemists.



CHAPTER XII

FIGHTING WITH FUMES

The Germans opened the war using projectiles seventeen inches in diameter. They closed it using projectiles one one-hundred millionth of an inch in diameter. And the latter were more effective than the former. As the dimensions were reduced from molar to molecular the battle became more intense. For when the Big Bertha had shot its bolt, that was the end of it. Whomever it hit was hurt, but after that the steel fragments of the shell lay on the ground harmless and inert. The men in the dugouts could hear the shells whistle overhead without alarm. But the poison gas could penetrate where the rifle ball could not. The malignant molecules seemed to search out their victims. They crept through the crevices of the subterranean shelters. They hunted for the pinholes in the face masks. They lay in wait for days in the trenches for the soldiers' return as a cat watches at the hole of a mouse. The cannon ball could be seen and heard. The poison gas was invisible and inaudible, and sometimes even the chemical sense which nature has given man for his protection, the sense of smell, failed to give warning of the approach of the foe.

The smaller the matter that man can deal with the more he can get out of it. So long as man was dependent for power upon wind and water his working capacity was very limited. But as soon as he passed over the border line from physics into chemistry and learned how to use the molecule, his efficiency in work and warfare was multiplied manifold. The molecular bombardment of the piston by steam or the gases of combustion runs his engines and propels his cars. The first man who wanted to kill another from a safe distance threw the stone by his arm's strength. David added to his arm the centrifugal force of a sling when he slew Goliath. The Romans improved on this by concentrating in a catapult the strength of a score of slaves and casting stone cannon balls to the top of the city wall. But finally man got closer to nature's secret and discovered that by loosing a swarm of gaseous molecules he could throw his projectile seventy-five miles and then by the same force burst it into flying fragments. There is no smaller projectile than the atom unless our belligerent chemists can find a way of using the electron stream of the cathode ray. But this so far has figured only in the pages of our scientific romancers and has not yet appeared on the battlefield. If, however, man could tap the reservoir of sub-atomic energy he need do no more work and would make no more war, for unlimited powers of construction and destruction would be at his command. The forces of the infinitesimal are infinite.

The reason why a gas is so active is because it is so egoistic. Psychologically interpreted, a gas consists of particles having the utmost aversion to one another. Each tries to get as far away from every other as it can. There is no cohesive force; no attractive impulse; nothing to draw them together except the all too feeble power of gravitation. The hotter they get the more they try to disperse and so the gas expands. The gas represents the extreme of individualism as steel represents the extreme of collectivism. The combination of the two works wonders. A hot gas in a steel cylinder is the most powerful agency known to man, and by means of it he accomplishes his greatest achievements in peace or war time.

The projectile is thrown from the gun by the expansive force of the gases released from the powder and when it reaches its destination it is blown to pieces by the same force. This is the end of it if it is a shell of the old-fashioned sort, for the gases of combustion mingle harmlessly with the air of which they are normal constituents. But if it is a poison gas shell each molecule as it is released goes off straight into the air with a speed twice that of the cannon ball and carries death with it. A man may be hit by a heavy piece of lead or iron and still survive, but an unweighable amount of lethal gas may be fatal to him.

Most of the novelties of the war were merely extensions of what was already known. To increase the caliber of a cannon from 38 to 42 centimeters or its range from 30 to 75 miles does indeed make necessary a decided change in tactics, but it is not comparable to the revolution effected by the introduction of new weapons of unprecedented power such as airplanes, submarines, tanks, high explosives or poison gas. If any army had been as well equipped with these in the beginning as all armies were at the end it might easily have won the war. That is to say, if the general staff of any of the powers had had the foresight and confidence to develop and practise these modes of warfare on a large scale in advance it would have been irresistible against an enemy unprepared to meet them. But no military genius appeared on either side with sufficient courage and imagination to work out such schemes in secret before trying them out on a small scale in the open. Consequently the enemy had fair warning and ample time to learn how to meet them and methods of defense developed concurrently with methods of attack. For instance, consider the motor fortresses to which Ludendorff ascribes his defeat. The British first sent out a few clumsy tanks against the German lines. Then they set about making a lot of stronger and livelier ones, but by the time these were ready the Germans had field guns to smash them and chain fences with concrete posts to stop them. On the other hand, if the Germans had followed up their advantage when they first set the cloud of chlorine floating over the battlefield of Ypres they might have won the war in the spring of 1915 instead of losing it in the fall of 1918. For the British were unprepared and unprotected against the silent death that swept down upon them on the 22nd of April, 1915. What happened then is best told by Sir Arthur Conan Doyle in his "History of the Great War."

From the base of the German trenches over a considerable length there appeared jets of whitish vapor, which gathered and swirled until they settled into a definite low cloud-bank, greenish-brown below and yellow above, where it reflected the rays of the sinking sun. This ominous bank of vapor, impelled by a northern breeze, drifted swiftly across the space which separated the two lines. The French troops, staring over the top of their parapet at this curious screen which ensured them a temporary relief from fire, were observed suddenly to throw up their hands, to clutch at their throats, and to fall to the ground in the agonies of asphyxiation. Many lay where they had fallen, while their comrades, absolutely helpless against this diabolical agency, rushed madly out of the mephitic mist and made for the rear, over-running the lines of trenches behind them. Many of them never halted until they had reached Ypres, while others rushed westwards and put the canal between themselves and the enemy. The Germans, meanwhile, advanced, and took possession of the successive lines of trenches, tenanted only by the dead garrisons, whose blackened faces, contorted figures, and lips fringed with the blood and foam from their bursting lungs, showed the agonies in which they had died. Some thousands of stupefied prisoners, eight batteries of French field-guns, and four British 4.7's, which had been placed in a wood behind the French position, were the trophies won by this disgraceful victory.

Under the shattering blow which they had received, a blow particularly demoralizing to African troops, with their fears of magic and the unknown, it was impossible to rally them effectually until the next day. It is to be remembered in explanation of this disorganization that it was the first experience of these poison tactics, and that the troops engaged received the gas in a very much more severe form than our own men on the right of Langemarck. For a time there was a gap five miles broad in the front of the position of the Allies, and there were many hours during which there was no substantial force between the Germans and Ypres. They wasted their time, however, in consolidating their ground, and the chance of a great coup passed forever. They had sold their souls as soldiers, but the Devil's price was a poor one. Had they had a corps of cavalry ready, and pushed them through the gap, it would have been the most dangerous moment of the war.

A deserter had come over from the German side a week before and told them that cylinders of poison gas had been laid in the front trenches, but no one believed him or paid any attention to his tale. War was then, in the Englishman's opinion, a gentleman's game, the royal sport, and poison was prohibited by the Hague rules. But the Germans were not playing the game according to the rules, so the British soldiers were strangled in their own trenches and fell easy victims to the advancing foe. Within half an hour after the gas was turned on 80 per cent. of the opposing troops were knocked out. The Canadians, with wet handkerchiefs over their faces, closed in to stop the gap, but if the Germans had been prepared for such success they could have cleared the way to the coast. But after such trials the Germans stopped the use of free chlorine and began the preparation of more poisonous gases. In some way that may not be revealed till the secret history of the war is published, the British Intelligence Department obtained a copy of the lecture notes of the instructions to the German staff giving details of the new system of gas warfare to be started in December. Among the compounds named was phosgene, a gas so lethal that one part in ten thousand of air may be fatal. The antidote for it is hexamethylene tetramine. This is not something the soldier—or anybody else—is accustomed to carry around with him, but the British having had a chance to cram up in advance on the stolen lecture notes were ready with gas helmets soaked in the reagent with the long name.

The Germans rejoiced when gas bombs took the place of bayonets because this was a field in which intelligence counted for more than brute force and in which therefore they expected to be supreme. As usual they were right in their major premise but wrong in their conclusion, owing to the egoism of their implicit minor premise. It does indeed give the advantage to skill and science, but the Germans were beaten at their own game, for by the end of the war the United States was able to turn out toxic gases at a rate of 200 tons a day, while the output of Germany or England was only about 30 tons. A gas plant was started at Edgewood, Maryland, in November, 1917. By March it was filling shell and before the war put a stop to its activities in the fall it was producing 1,300,000 pounds of chlorine, 1,000,000 pounds of chlorpicrin, 1,300,000 pounds of phosgene and 700,000 pounds of mustard gas a month.

Chlorine, the first gas used, is unpleasantly familiar to every one who has entered a chemical laboratory or who has smelled the breath of bleaching powder. It is a greenish-yellow gas made from common salt. The Germans employed it at Ypres by laying cylinders of the liquefied gas in the trenches, about a yard apart, and running a lead discharge pipe over the parapet. When the stop cocks are turned the gas streams out and since it is two and a half times as heavy as air it rolls over the ground like a noisome mist. It works best when the ground slopes gently down toward the enemy and when the wind blows in that direction at a rate between four and twelve miles an hour. But the wind, being strictly neutral, may change its direction without warning and then the gases turn back in their flight and attack their own side, something that rifle bullets have never been known to do.



Because free chlorine would not stay put and was dependent on the favor of the wind for its effect, it was later employed, not as an elemental gas, but in some volatile liquid that could be fired in a shell and so released at any particular point far back of the front trenches.

The most commonly used of these compounds was phosgene, which, as the reader can see by inspection of its formula, COCl_{2}, consists of chlorine (Cl) combined with carbon monoxide (CO), the cause of deaths from illuminating gas. These two poisonous gases, chlorine and carbon monoxide, when mixed together, will not readily unite, but if a ray of sunlight falls upon the mixture they combine at once. For this reason John Davy, who discovered the compound over a hundred years ago, named it phosgene, that is, "produced by light." The same roots recur in hydrogen, so named because it is "produced from water," and phosphorus, because it is a "light-bearer."

In its modern manufacture the catalyzer or instigator of the combination is not sunlight but porous carbon. This is packed in iron boxes eight feet long, through which the mixture of the two gases was forced. Carbon monoxide may be made by burning coke with a supply of air insufficient for complete combustion, but in order to get the pure gas necessary for the phosgene common air was not used, but instead pure oxygen extracted from it by a liquid air plant.

Phosgene is a gas that may be condensed easily to a liquid by cooling it down to 46 degrees Fahrenheit. A mixture of three-quarters chlorine with one-quarter phosgene has been found most effective. By itself phosgene has an inoffensive odor somewhat like green corn and so may fail to arouse apprehension until a toxic concentration is reached. But even small doses have such an effect upon the heart action for days afterward that a slight exertion may prove fatal.

The compound manufactured in largest amount in America was chlorpicrin. This, like the others, is not so unfamiliar as it seems. As may be seen from its formula, CCl{3}NO{2}, it is formed by joining the nitric acid radical (NO{2}), found in all explosives, with the main part of chloroform (HCCl{3}). This is not quite so poisonous as phosgene, but it has the advantage that it causes nausea and vomiting. The soldier so affected is forced to take off his gas mask and then may fall victim to more toxic gases sent over simultaneously.

Chlorpicrin is a liquid and is commonly loaded in a shell or bomb with 20 per cent. of tin chloride, which produces dense white fumes that go through gas masks. It is made from picric acid (trinitrophenol), one of the best known of the high explosives, by treatment with chlorine. The chlorine is obtained, as it is in the household, from common bleaching powder, or "chloride of lime." This is mixed with water to form a cream in a steel still 18 feet high and 8 feet in diameter. A solution of calcium picrate, that is, the lime salt of picric acid, is pumped in and as the reaction begins the mixture heats up and the chlorpicrin distils over with the steam. When the distillate is condensed the chlorpicrin, being the heavier liquid, settles out under the layer of water and may be drawn off to fill the shell.

Much of what a student learns in the chemical laboratory he is apt to forget in later life if he does not follow it up. But there are two gases that he always remembers, chlorine and hydrogen sulfide. He is lucky if he has escaped being choked by the former or sickened by the latter. He can imagine what the effect would be if two offensive fumes could be combined without losing their offensive features. Now a combination something like this is the so-called mustard gas, which is not a gas and is not made from mustard. But it is easily gasified, and oil of mustard is about as near as Nature dare come to making such sinful stuff. It was first made by Guthrie, an Englishman, in 1860, and rediscovered by a German chemist, Victor Meyer, in 1886, but he found it so dangerous to work with that he abandoned the investigation. Nobody else cared to take it up, for nobody could see any use for it. So it remained in innocuous desuetude, a mere name in "Beilstein's Dictionary," together with the thousands of other organic compounds that have been invented and never utilized. But on July 12, 1917, the British holding the line at Ypres were besprinkled with this villainous substance. Its success was so great that the Germans henceforth made it their main reliance and soon the Allies followed suit. In one offensive of ten days the Germans are said to have used a million shells containing 2500 tons of mustard gas.

The making of so dangerous a compound on a large scale was one of the most difficult tasks set before the chemists of this and other countries, yet it was successfully solved. The raw materials are chlorine, alcohol and sulfur. The alcohol is passed with steam through a vertical iron tube filled with kaolin and heated. This converts the alcohol into a gas known as ethylene (C{2}H{4}). Passing a stream of chlorine gas into a tank of melted sulfur produces sulfur monochloride and this treated with the ethylene makes the "mustard." The final reaction was carried on at the Edgewood Arsenal in seven airtight tanks or "reactors," each having a capacity of 30,000 pounds. The ethylene gas being led into the tank and distributed through the liquid sulfur chloride by porous blocks or fine nozzles, the two chemicals combined to form what is officially named "di-chlor-di-ethyl-sulfide" (ClC{2}H{4}SC{2}H{4}Cl). This, however, is too big a mouthful, so even the chemists were glad to fall in with the commonalty and call it "mustard gas."

The effectiveness of "mustard" depends upon its persistence. It is a stable liquid, evaporating slowly and not easily decomposed. It lingers about trenches and dugouts and impregnates soil and cloth for days. Gas masks do not afford complete protection, for even if they are impenetrable they must be taken off some time and the gas lies in wait for that time. In some cases the masks were worn continuously for twelve hours after the attack, but when they were removed the soldiers were overpowered by the poison. A place may seem to be free from it but when the sun heats up the ground the liquid volatilizes and the vapor soaks through the clothing. As the men become warmed up by work their skin is blistered, especially under the armpits. The mustard acts like steam, producing burns that range from a mere reddening to serious ulcerations, always painful and incapacitating, but if treated promptly in the hospital rarely causing death or permanent scars. The gas attacks the eyes, throat, nose and lungs and may lead to bronchitis or pneumonia. It was found necessary at the front to put all the clothing of the soldiers into the sterilizing ovens every night to remove all traces of mustard. General Johnson and his staff in the 77th Division were poisoned in their dugouts because they tried to alleviate the discomfort of their camp cots by bedding taken from a neighboring village that had been shelled the day before.

Of the 925 cases requiring medical attention at the Edgewood Arsenal 674 were due to mustard. During the month of August 3-1/2 per cent. of the mustard plant force were sent to the hospital each day on the average. But the record of the Edgewood Arsenal is a striking demonstration of what can be done in the prevention of industrial accidents by the exercise of scientific prudence. In spite of the fact that from three to eleven thousand men were employed at the plant for the year 1918 and turned out some twenty thousand tons of the most poisonous gases known to man, there were only three fatalities and not a single case of blindness.

Besides the four toxic gases previously described, chlorine, phosgene, chlorpicrin and mustard, various other compounds have been and many others might be made. A list of those employed in the present war enumerates thirty, among them compounds of bromine, arsenic and cyanogen that may prove more formidable than any so far used. American chemists kept very mum during the war but occasionally one could not refrain from saying: "If the Kaiser knew what I know he would surrender unconditionally by telegraph." No doubt the science of chemical warfare is in its infancy and every foresighted power has concealed weapons of its own in reserve. One deadly compound, whose identity has not yet been disclosed, is known as "Lewisite," from Professor Lewis of Northwestern, who was manufacturing it at the rate of ten tons a day in the "Mouse Trap" stockade near Cleveland.

Throughout the history of warfare the art of defense has kept pace with the art of offense and the courage of man has never failed, no matter to what new danger he was exposed. As each new gas employed by the enemy was detected it became the business of our chemists to discover some method of absorbing or neutralizing it. Porous charcoal, best made from such dense wood as coconut shells, was packed in the respirator box together with layers of such chemicals as will catch the gases to be expected. Charcoal absorbs large quantities of any gas. Soda lime and potassium permanganate and nickel salts were among the neutralizers used.

The mask is fitted tightly about the face or over the head with rubber. The nostrils are kept closed with a clip so breathing must be done through the mouth and no air can be inhaled except that passing through the absorbent cylinder. Men within five miles of the front were required to wear the masks slung on their chests so they could be put on within six seconds. A well-made mask with a fresh box afforded almost complete immunity for a time and the soldiers learned within a few days to handle their masks adroitly. So the problem of defense against this new offensive was solved satisfactorily, while no such adequate protection against the older weapons of bayonet and shrapnel has yet been devised.

Then the problem of the offense was to catch the opponent with his mask off or to make him take it off. Here the lachrymators and the sternutators, the tear gases and the sneeze gases, came into play. Phenylcarbylamine chloride would make the bravest soldier weep on the battlefield with the abandonment of a Greek hero. Di-phenyl-chloro-arsine would set him sneezing. The Germans alternated these with diabolical ingenuity so as to catch us unawares. Some shells gave off voluminous smoke or a vile stench without doing much harm, but by the time our men got used to these and grew careless about their masks a few shells of some extremely poisonous gas were mixed with them.

The ideal gas for belligerent purposes would be odorless, colorless and invisible, toxic even when diluted by a million parts of air, not set on fire or exploded by the detonator of the shell, not decomposed by water, not readily absorbed, stable enough to stand storage for six months and capable of being manufactured by the thousands of tons. No one gas will serve all aims. For instance, phosgene being very volatile and quickly dissipated is thrown into trenches that are soon to be taken while mustard gas being very tenacious could not be employed in such a case for the trenches could not be occupied if they were captured.

The extensive use of poison gas in warfare by all the belligerents is a vindication of the American protest at the Hague Conference against its prohibition. At the First Conference of 1899 Captain Mahan argued very sensibly that gas shells were no worse than other projectiles and might indeed prove more merciful and that it was illogical to prohibit a weapon merely because of its novelty. The British delegates voted with the Americans in opposition to the clause "the contracting parties agree to abstain from the use of projectiles the sole object of which is the diffusion of asphyxiating or deleterious gases." But both Great Britain and Germany later agreed to the provision. The use of poison gas by Germany without warning was therefore an act of treachery and a violation of her pledge, but the United States has consistently refused to bind herself to any such restriction. The facts reported by General Amos A. Fries, in command of the overseas branch of the American Chemical Warfare Service, give ample support to the American contention at The Hague:

Out of 1000 gas casualties there are from 30 to 40 fatalities, while out of 1000 high explosive casualties the number of fatalities run from 200 to 250. While exact figures are as yet not available concerning the men permanently crippled or blinded by high explosives one has only to witness the debarkation of a shipload of troops to be convinced that the number is very large. On the other hand there is, so far as known at present, not a single case of permanent disability or blindness among our troops due to gas and this in face of the fact that the Germans used relatively large quantities of this material.

In the light of these facts the prejudice against the use of gas must gradually give way; for the statement made to the effect that its use is contrary to the principles of humanity will apply with far greater force to the use of high explosives. As a matter of fact, for certain purposes toxic gas is an ideal agent. For example, it is difficult to imagine any agent more effective or more humane that may be used to render an opposing battery ineffective or to protect retreating troops.

Captain Mahan's argument at The Hague against the proposed prohibition of poison gas is so cogent and well expressed that it has been quoted in treatises on international law ever since. These reasons were, briefly:

1. That no shell emitting such gases is as yet in practical use or has undergone adequate experiment; consequently, a vote taken now would be taken in ignorance of the facts as to whether the results would be of a decisive character or whether injury in excess of that necessary to attain the end of warfare—the immediate disabling of the enemy—would be inflicted.

2. That the reproach of cruelty and perfidy, addressed against these supposed shells, was equally uttered formerly against firearms and torpedoes, both of which are now employed without scruple. Until we know the effects of such asphyxiating shells, there was no saying whether they would be more or less merciful than missiles now permitted. That it was illogical, and not demonstrably humane, to be tender about asphyxiating men with gas, when all are prepared to admit that it was allowable to blow the bottom out of an ironclad at midnight, throwing four or five hundred into the sea, to be choked by water, with scarcely the remotest chance of escape.

As Captain Mahan says, the same objection has been raised at the introduction of each new weapon of war, even though it proved to be no more cruel than the old. The modern rifle ball, swift and small and sterilized by heat, does not make so bad a wound as the ancient sword and spear, but we all remember how gunpowder was regarded by the dandies of Hotspur's time:

And it was great pity, so it was, This villainous saltpeter should be digg'd Out of the bowels of the harmless earth Which many a good tall fellow had destroy'd So cowardly; and but for these vile guns He would himself have been a soldier.

The real reason for the instinctive aversion manifested against any new arm or mode of attack is that it reveals to us the intrinsic horror of war. We naturally revolt against premeditated homicide, but we have become so accustomed to the sword and latterly to the rifle that they do not shock us as they ought when we think of what they are made for. The Constitution of the United States prohibits the infliction of "cruel and unusual punishments." The two adjectives were apparently used almost synonymously, as though any "unusual" punishment were necessarily "cruel," and so indeed it strikes us. But our ingenious lawyers were able to persuade the courts that electrocution, though unknown to the Fathers and undeniably "unusual," was not unconstitutional. Dumdum bullets are rightfully ruled out because they inflict frightful and often incurable wounds, and the aim of humane warfare is to disable the enemy, not permanently to injure him.



In spite of the opposition of the American and British delegates the First Hague Conference adopted the clause, "The contracting powers agree to abstain from the use of projectiles the [sole] object of which is the diffusion of asphyxiating or deleterious gases." The word "sole" (unique) which appears in the original French text of The Hague convention is left out of the official English translation. This is a strange omission considering that the French and British defended their use of explosives which diffuse asphyxiating and deleterious gases on the ground that this was not the "sole" purpose of the bombs but merely an accidental effect of the nitric powder used.

The Hague Congress of 1907 placed in its rules for war: "It is expressly forbidden to employ poisons or poisonous weapons." But such attempts to rule out new and more effective means of warfare are likely to prove futile in any serious conflict and the restriction gives the advantage to the most unscrupulous side. We Americans, if ever we give our assent to such an agreement, would of course keep it, but our enemy—whoever he may be in the future—will be, as he always has been, utterly without principle and will not hesitate to employ any weapon against us. Besides, as the Germans held, chemical warfare favors the army that is most intelligent, resourceful and disciplined and the nation that stands highest in science and industry. This advantage, let us hope, will be on our side.



CHAPTER XIII

PRODUCTS OF THE ELECTRIC FURNACE

The control of man over the materials of nature has been vastly enhanced by the recent extension of the range of temperature at his command. When Fahrenheit stuck the bulb of his thermometer into a mixture of snow and salt he thought he had reached the nadir of temperature, so he scratched a mark on the tube where the mercury stood and called it zero. But we know that absolute zero, the total absence of heat, is 459 of Fahrenheit's degrees lower than his zero point. The modern scientist can get close to that lowest limit by making use of the cooling by the expansion principle. He first liquefies air under pressure and then releasing the pressure allows it to boil off. A tube of hydrogen immersed in the liquid air as it evaporates is cooled down until it can be liquefied. Then the boiling hydrogen is used to liquefy helium, and as this boils off it lowers the temperature to within three or four degrees of absolute zero.

The early metallurgist had no hotter a fire than he could make by blowing charcoal with a bellows. This was barely enough for the smelting of iron. But by the bringing of two carbon rods together, as in the electric arc light, we can get enough heat to volatilize the carbon at the tips, and this means over 7000 degrees Fahrenheit. By putting a pressure of twenty atmospheres onto the arc light we can raise it to perhaps 14,000 degrees, which is 3000 degrees hotter than the sun. This gives the modern man a working range of about 14,500 degrees, so it is no wonder that he can perform miracles.

When a builder wants to make an old house over into a new one he takes it apart brick by brick and stone by stone, then he puts them together in such new fashion as he likes. The electric furnace enables the chemist to take his materials apart in the same way. As the temperature rises the chemical and physical forces that hold a body together gradually weaken. First the solid loosens up and becomes a liquid, then this breaks bonds and becomes a gas. Compounds break up into their elements. The elemental molecules break up into their component atoms and finally these begin to throw off corpuscles of negative electricity eighteen hundred times smaller than the smallest atom. These electrons appear to be the building stones of the universe. No indication of any smaller units has been discovered, although we need not assume that in the electron science has delivered, what has been called, its "ultim-atom." The Greeks called the elemental particles of matter "atoms" because they esteemed them "indivisible," but now in the light of the X-ray we can witness the disintegration of the atom into electrons. All the chemical and physical properties of matter, except perhaps weight, seem to depend upon the number and movement of the negative and positive electrons and by their rearrangement one element may be transformed into another.

So the electric furnace, where the highest attainable temperature is combined with the divisive and directive force of the current, is a magical machine for accomplishment of the metamorphoses desired by the creative chemist. A hundred years ago Davy, by dipping the poles of his battery into melted soda lye, saw forming on one of them a shining globule like quicksilver. It was the metal sodium, never before seen by man. Nowadays this process of electrolysis (electric loosening) is carried out daily by the ton at Niagara.

The reverse process, electro-synthesis (electric combining), is equally simple and even more important. By passing a strong electric current through a mixture of lime and coke the metal calcium disengages itself from the oxygen of the lime and attaches itself to the carbon. Or, to put it briefly,

CaO + 3C —> CaC_{2} + CO lime coke calcium carbon carbide monoxide

This reaction is of peculiar importance because it bridges the gulf between the organic and inorganic worlds. It was formerly supposed that the substances found in plants and animals, mostly complex compounds of carbon, hydrogen and oxygen, could only be produced by "vital forces." If this were true it meant that chemistry was limited to the mineral kingdom and to the extraction of such carbon compounds as happened to exist ready formed in the vegetable and animal kingdoms. But fortunately this barrier to human achievement proved purely illusory. The organic field, once man had broken into it, proved easier to work in than the inorganic.