Part 33
What is the greatest discovery of the last twenty-five years? Probably you will say the wireless telegraph, the flying machine, moving pictures or the phonograph, but it would be none of these, according to the _Scientific American_. This publication discussed at great length the subject of what invention of the last twenty-five years was of greatest value to mankind. First place was given not to the wonderful inventions that are so large in the public eye, but to the fixation of nitrogen from the air for fertilizer purposes. Why? Simply because this discovery stands between man and starvation. Other inventions are vastly important, but this one is vital. Looking at it from the broadest view there can be no other decision. The time is here when to feed the world is becoming a more and more difficult problem.
During the past ten years our population has increased at the rate of two per cent per annum, while our crop production has increased only one-half as fast. In six years the number of beef cattle produced in this country has fallen off about five per cent per annum. The cost of foodstuffs recently has been increasing at the rate of five per cent per annum. The hardships experienced by wage-earners, particularly in the United States, have been very great in view of the fact that the cost of food increased more rapidly than wages--at a rate approximately double. The same tendencies apply with some modifications to the clothing of mankind. These facts point to the necessity of increasing the yields both of the food crops and the crops that are used in the making of clothing.
The problem of decreasing the cost of living has been given far more attention abroad than it has in this country, owing to the much greater density of population in the principal nations of Europe. For a long time it has been known that plants require food the same as animals and human beings. Without food plants cannot live and grow, and just to the extent that plant food is present in the soil, to that extent will a crop be produced. The most important of plant foods is nitrogen. While the earth is literally bathed in nitrogen, this element is found to only a very slight degree in the soil. That is to say, the air which we breathe and in which we move is four-fifths nitrogen, yet in the richest soil there is seldom more than one-tenth or two-tenths of one per cent of nitrogen. Put on a wheat crop one pound of nitrogen and you can take off twenty pounds more wheat and forty pounds more straw than you could if you failed to make this application. One pound of nitrogen properly applied to a cornfield will add thirty-five pounds to the crop; one pound of nitrogen will produce one hundred pounds of increase in the potato crop; one pound of nitrogen will produce five pounds of cotton, without any extra labor being devoted to the production of the crop. Nitrogen is the heart and soul of the problem of growing more crops and cheaper crops. Take any nation that produces large crop yields per acre and you will find that the nation that uses the most nitrogen per acre grows the largest crops.
For years the nations of Europe have been depending to a great extent upon supplies of nitrate of soda obtained from Chile, in South America. Germany alone imported nearly a million tons of this salt annually before the war. Then, too, the by-products of many industries furnish a quantity of nitrogen, but all this, it was realized, furnished but a small part of what was required to combat the constantly rising cost of producing food.
For years it was the dream and life-ambition of the world’s greatest scientists to discover how to make the supplies of nitrogen in the air available to plants as food. The only way that this could be done in nature was through the agency of bacteria working on the roots of certain plants, such as clovers, but this process was entirely too slow for practical purposes and could be applied on only a small acreage at one time. The free nitrogen of the air cannot be utilized directly by plants. It must first be converted into some combination with other chemicals, as a solid or liquid, which can be absorbed by the plant. Among others who worked on the problem of fixing atmospheric nitrogen were two German chemists, Doctors Caro and Frank, who found that a compound of calcium and carbon heated to a high temperature would absorb nitrogen and retain it in a form that could be applied to the soil and serve as a food for plants.
This discovery is the basis of the Cyanamid “Atmospheric Nitrogen” industry or the making of fertilizer from the nitrogen in the air. After the discovery was made and tested on the laboratory scale it took several years to put it on a practical basis, as can well be imagined when it is understood what the problems involved were. Besides air this process required as raw materials limestone and coke. The limestone must be burned to quicklime and the quicklime and coke must be fused together to form calcium carbide. Only the most powerful electric furnaces are capable of performing this work. Any other means of heating is far from adequate. For instance, the hottest flame that can be produced by the burning of gas, namely, the oxy-hydrogen blow-pipe flame, can be directed against a stick of burnt lime without doing anything beyond making the lime glow brilliantly, thus producing the calcium or lime-light formerly much used in theaters as a spot-light. In the electric furnaces, however, the lime is heated so powerfully that it actually melts to a liquid, and in this condition it dissolves the coke with which it is mixed and the compound resulting is calcium carbide which can be run off from the interior of the furnace in liquid form.
At the cyanamid plant at Niagara Falls, in Canada, there are seven of these great carbide furnaces, each about fifteen feet long and half as wide and one-third as deep. We all have some idea of how much heat is generated in the ordinary electric arc light such as is used for street lighting. In the carbide furnace the carbon pencil, instead of being six or eight inches long and as large around as your finger, is six feet long and two feet in diameter. There are three of these in each furnace, and when the furnace is in full action it can be imagined that there is a terrific heat generated; in fact, when the fused lime and coke come out of the furnace in the form of molten carbide the brightness of the molten material is so dazzling that one cannot look at it with the naked eyes without injury.
Then there is the problem of producing pure nitrogen gas, that is, separating the eighty per cent of nitrogen in the air from the twenty per cent of oxygen. The latter is the element that we breathe and which passes into the body, there to combine with the impurities resulting from the various life activities. If the nitrogen and the oxygen were both allowed to act upon calcium carbide the oxygen would burn up the carbide before the nitrogen could be fixed in it, hence these two elements must be separated and all other impurities removed so that only chemically pure nitrogen is brought to the calcium carbide for fixation. The separation is accomplished by means of liquid air machines. This industry, therefore, not only utilizes the greatest heat obtainable on a practical scale, but it also utilizes the greatest cold. While the electric furnaces produce a temperature of over 4000° F., or about twice as hot as molten cast-iron, the liquid air machines work at a temperature of 372° F. below zero. The air must first be purified and dried. It is then compressed, cooled while under pressure, and then expanded. The expansion lowers its temperature considerably. If this extra cool air is used for cooling another batch of air under pressure, the latter upon expansion becomes still colder than the first batch expanded. By repeating this operation the final temperature of 372° below zero is reached, at which the air liquifies.
How cold this is can be seen from some simple experiments. For instance, if a dipper full of the liquid air is drawn, in an instant the outside of the dipper is covered with a coating of frost deposited upon it from the surrounding atmosphere. The surrounding air is so much hotter than the liquid air that the liquid boils violently. If a piece of rubber hose is held in the liquid air for eight or ten seconds and then struck with a hammer the rubber flies into pieces just like glass. To dip one’s finger into this liquid air would freeze it solid in a second and would be as disastrous as dipping it in red-hot iron.
When the liquid air is allowed to warm up a little, the nitrogen gas evaporates, while the oxygen remains behind in the liquid. The pure nitrogen then can be pumped into the fixation ovens.
To fix the nitrogen in the carbide it is necessary to cool the latter after it comes from the electric furnaces and grind it to a very fine powder. This powder is then placed in furnaces that look like steel barrels but are three or four times larger than an ordinary barrel. The oven filled with calcium carbide is then electrically heated with a carbon rod running through the center. When the temperature is about as hot as that of molten iron the pure nitrogen gas from the liquid air plant is pumped in and allowed to act on the calcium carbide for about a day and a half. When the carbide has absorbed all it will absorb the crude cyanamid formed is removed from the oven as a single large cake which is run through pulverizing drums and then put through an elaborate process of refinement and finally bagged for shipment in carload lots to fertilizer factories throughout the country.
The fertilizer manufacturers mix the cyanamid with other ingredients to make a balanced plant food and so ship it to farmers for feeding their crops. In 1914 7,500,000 tons of fertilizer worth $175,000,000 were consumed in this country. This seems like a large quantity, but it allows only a scanty application per acre cultivated. Germany, on one-fourth of our cultivated acreage, uses almost twice as much fertilizer as the entire United States. As a consequence she raises 30 bushels of wheat where we average 14 bushels per acre; 52 bushels of oats where we average 30; and 196 bushels of potatoes per acre where we raise 97 bushels per acre. The explanation is simple, German farmers pay only about one-half as much for their plant food as American farmers pay. Where the German farmer gains $2.00 to $3.00 increase in crop from fertilizer that costs him $1.00 the American farmer pays $2.00 for the same fertilizer, which leaves him less profit and less incentive to use fertilizer.
The air-nitrogen industry in the United States is said to be considerably handicapped because the large quantities of electricity required are not available at a low enough price. There are excellent water-power sites in the United States sufficient to furnish many times the required power, but the existing water-power laws are so burdensome that investors will not put their money into power development except on such high terms that the power is much dearer than it can be bought for in other countries. Practically every civilized country in the world, except the United States, had one or more cyanamid factories in 1916. These include Germany, Austria-Hungary, Great Britain, France, Italy, Switzerland, Norway, Sweden, Japan and Canada. Their combined output is about 1,000,000 tons per annum. The cyanamid plant at Niagara Falls, Ontario, which was established in 1909, with a capacity of 10,000 tons, had a capacity of 64,000 tons per annum in 1916. It utilizes about 30,000 electrical horse-power twenty-four hours a day, and three hundred and sixty-five days a year. Germany, at the beginning of the war, produced about 30,000 tons of cyanamid; in 1916 she was making 600,000 tons a year. She is using it both to grow crops and to make explosives for her guns.
At the time the war broke out, in August, 1914, Germany was importing nearly one million tons of nitrate of soda per annum from Chile, South America. This supply was immediately cut off by enemy fleets. Not only was her agriculture thereby threatened with a great decrease in crop production but her supply of military explosives was also threatened. Professor Dr. Lemmermann, a famous German scientist, advised his government that unless the nitrogen shortage were made good the resulting crop shortage would amount to 3,300,000 tons of grain. But if people require food, guns require powder, and no powder can be made without nitric acid. It has been reported on good authority that Germany has consumed one and one-third million pounds of powder a day during the war. To make one pound of powder requires one and one-half pounds of nitric acid, so that Germany required for military purposes 2,000,000 pounds of nitric acid per day. From her coke ovens she indeed could derive some nitrogen, but this actually furnished only about one-fifth of her total requirements. For the other four-fifths she turned to atmospheric nitrogen. For it is also true that this remarkable compound, cyanamid, which is a food for plants, can be decomposed by high-steam pressure into the purest ammonia gas. The ammonia can in turn be oxidized to nitric acid, which is the basis of all explosives. Without the fixation of atmospheric nitrogen on a tremendous scale there is no doubt that Germany would have become helpless before her enemies within a year after the war began, for no nation can fight unless it has sufficient food for its people and powder for its guns.
The preservation of food is also dependent on ammonia, which produces the refrigerating effect in the numerous cold storage houses and artificial ice plants in this country. In the cold storage plants alone the cold produced by means of ammonia is equal to 750,000 tons of ice consumed per day, while 25,000,000 tons of artificial ice are produced and sold as such per annum. Cyanamid ammonia gas is especially valuable for this purpose on account of its high degree of purity.
Then, too, the ammonia gas can be fixed in any acid desired, for instance, in phosphoric acid, making ammonium phosphate, a fertilizer of unusual merit, or ammonium sulphate, another fertilizer, or ammonium nitrate, an explosive. So, for peace or war, the fixation of atmospheric nitrogen has become a tremendous factor in the life of nations.
If the United States should be forced into war with a foreign power it would be a simple matter for an enemy fleet to cut off our large importations of nitrate of soda from Chile. These amount to about 700,000 tons per annum in normal times and at present about 900,000 tons per annum. In other words, we would be short just this quantity of nitrogen in addition to the quantity that would be required by the government for the manufacture of military explosives. It has been suggested that our coke-oven industry could be expanded to furnish a large part of this requirement, but even with the largest expansion considered practical by the coke-oven people within the next several years, the coke ovens would not be able to supply even one-third of our requirements, thus leaving a large balance which could be furnished only by the establishment of a large nitrogen industry in this country.
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The expression “The King can do no wrong” has been widely used since it first caught people’s fancy at the time of the explanation, made in England, that the Ministers, and not the King, were responsible for mistakes of government.
What is a Drawbridge Like Today?
We have all read of the castles in olden days into which the owner could retire and raise a drawbridge across a ditch, thus putting a barrier in the way of his enemies.
That old style drawbridge, with, of course, many improvements, has been adopted in these modern times to use in permitting navigable rivers and channels to be crossed by railroads and other kinds of transportation, without preventing the passage of vessels up and down the rivers.
Modern drawbridges across rivers, canals, the entrances of docks, etc., are generally made to open vertically, and the movable portion is called a bascule, balance or lifting bridge; a turning, swivel or swing bridge; or a rolling bridge, in accordance with the mode in which it is made to open.
Swing bridges are usually divided into two parts meeting in the middle, and each moved on pivots on the opposite sides of the channel, or they may move as a whole on a pivot in the middle of the channel.
Rolling bridges are suspended from a structure high above the water, and are propelled backwards and forwards by means of rollers.
The advantages of this type of bridge are that the entire width of the channel is available for navigation, and the draw may be opened and closed more readily than the swing type.]
The Story of a Deep Sea Monster[54]
The early day was blue and silver; one of those colorful mornings peculiar to southern Florida. Sandwiched between the earth and the turquoise sky, the Atlantic lay gleaming like a huge silver wafer in the sunlight. Not the faintest suggestion of a ripple marred its shining surface.
Suddenly out of the stillness of the silver water a huge black fin was lifted, and a little group of men lounging on the deck of an idle fishing craft drew near the rail and used their glasses.
“Shark,” remarked the captain pleasantly after a moment’s scrutiny. “Who wants to go out with me for a little fun?”
The hastily lowered lifeboat pointed a slim nose toward the large black shape thrashing about in the shallow water. Three men were in the boat--Captain Charles H. Thompson of the yacht “Samoa,” one of the yacht’s crew, and a winter visitor to southern Florida. As they drew near, the sailor took one look at the gigantic creature and yelled to the captain:
“For heaven’s sake, man, don’t harpoon that thing; we will be crushed like an egg shell!”
Poised in the bow of the boat, harpoon in hand, stood the captain, and as they drew alongside there was a flash; the steel glittered for a moment in the sunlight, then sank into the huge black bulk. Simultaneously the little boat spun around and shot out toward the Gulf Stream like an agitated and very erratic rocket, flinging great sheets of spray high into the air as it sped.
Thus began a thirty-nine hours’ ride filled with wildest thrills, during which time Captain Thompson battled with the fish, the sailor bailed the boat unceasingly, lest they be swamped, and the tourist raised an anxious and eloquent voice to high heaven. The men were without food the entire time, sharing only a small bottle of water among them.
The news of the struggle spread rapidly, and soon hundreds of interested spectators gathered on the trestle of the East Coast sea-extension railway. Scores of times the men in the boat escaped death only by a miracle, as the wildly thrashing black tail missed them but by a hair’s breadth. Finally, after two days and one night, the monster was worn out, and the triumphant captor managed to fasten it to the trestle work on Knight’s Key, where, after a few hours’ rest, it wigwagged a festive tail, smashing the large pilings as though they were toothpicks. After another battle the fish was firmly tied up once more, this time to the yacht “Samoa;” and again it waved a wicked tail, disabling the thirty-ton yacht by smashing her propeller and breaking the cables. A tug was then summoned, and the big fellow was towed one hundred and ten miles to Miami, Florida, where it was viewed by thousands of people.
Five harpoons and one hundred and fifty-one bullets were used in subduing the monster, and it took five days to finally kill it.
It was thought at first the creature was a whale, but later it was classified as a fish, for it breathed through gills of which there were five in number. Upon careful examination it seemed probable that it was a baby of its species, as the backbone was of a cartilaginous nature, a condition found only in a young creature; in a full-grown one this develops into true bone. That it was a deep-sea fish was indicated by the small eye, which was about the size of a silver dollar. The pressure of the water is so great at the bottom of the ocean that were the eyes large they would be ruptured. That the pupil did not dilate and contract seems additional proof that the fish must have lived at a depth of probably fifteen hundred or two thousand feet, where there is little light.
It is generally believed that some volcanic eruption drove the fish to the surface where, owing to the difference in water pressure, the swim-bladders burst, making it impossible for him to return to his level.
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What is an Armored Railway Car Like?
The armored car shown in this picture is the first of a new type of armored car to be constructed by the United States. It was designed under the direction of the Board of Engineers of the U. S. Army, and was constructed by the Standard Steel Car Company, Pittsburgh, Pa., at their Hammond, Ind., plant. The car was designed and built within twenty-seven days.