Creative Chemistry Part 17

I shoot the hippopotamus with bullets made of platinum, Because if I use leaden ones, his hide is sure to flatten 'em.

Along in the latter half of the last century chemists had begun to perceive certain regularities and relations.h.i.+ps among the various elements, so they conceived the idea that some sort of a pigeon-hole scheme might be devised in which the elements could be filed away in the order of their atomic weights so that one could see just how a certain element, known or unknown, would behave from merely observing its position in the series. Mendeleef, a Russian chemist, devised the most ingenious of such systems called the "periodic law" and gave proof that there was something in his theory by predicting the properties of three metallic elements, then unknown but for which his arrangement showed three empty pigeon-holes. Sixteen years later all three of these predicted elements had been discovered, one by a Frenchman, one by a German and one by a Scandinavian, and named from patriotic impulse, gallium, germanium and scandium. This was a triumph of scientific prescience as striking as the mathematical proof of the existence of the planet Neptune by Leverrier before it had been found by the telescope.

But although Mendeleef's law told "the truth," it gradually became evident that it did not tell "the whole truth and nothing but the truth," as the lawyers put it. As usually happens in the history of science the hypothesis was found not to explain things so simply and completely as was at first a.s.sumed. The anomalies in the arrangement did not disappear on closer study, but stuck out more conspicuously. Though Mendeleef had pointed out three missing links, he had failed to make provision for a whole group of elements since discovered, the inert gases of the helium-argon group. As we now know, the scheme was built upon the false a.s.sumptions that the elements are immutable and that their atomic weights are invariable.

The elements that the chemists had most difficulty in sorting out and identifying were the heavy metals found in the "rare earths." There were about twenty of them so mixed up together and so much alike as to baffle all ordinary means of separating them. For a hundred years chemists worked over them and quarreled over them before they discovered that they had a commercial value. It was a problem as remote from practicality as any that could be conceived. The man in the street did not see why chemists should care whether there were two didymiums any more than why theologians should care whether there were two Isaiahs.

But all of a sudden, in 1885, the chemical puzzle became a business proposition. The rare earths became household utensils and it made a big difference with our monthly gas bills whether the ceria and the thoria in the burner mantles were absolutely pure or contained traces of some of the other elements that were so difficult to separate.

This sudden change of venue from pure to applied science came about through a Viennese chemist, Dr. Carl Auer, later and in consequence known as Baron Auer von Welsbach. He was trying to sort out the rare earths by means of the spectroscopic method, which consists ordinarily in dipping a platinum wire into a solution of the unknown substance and holding it in a colorless gas flame. As it burns off, each element gives a characteristic color to the flame, which is seen as a series of lines when looked at through the spectroscope. But the flash of the flame from the platinum wire was too brief to be studied, so Dr. Auer hit upon the plan of soaking a thread in the liquid and putting this in the gas jet.

The cotton of course burned off at once, but the earths held together and when heated gave off a brilliant white light, very much like the calcium or limelight which is produced by heating a stick of quicklime in the oxy-hydrogen flame. But these rare earths do not require any such intense heat as that, for they will glow in an ordinary gas jet.

So the Welsbach mantle burner came into use everywhere and rescued the coal gas business from the destruction threatened by the electric light.

It was no longer necessary to enrich the gas with oil to make its flame luminous, for a cheaper fuel gas such as is used for a gas stove will give, with a mantle, a fine white light of much higher candle power than the ordinary gas jet. The mantles are knit in narrow cylinders on machines, cut off at suitable lengths, soaked in a solution of the salts of the rare earths and dried. Artificial silk (viscose) has been found better than cotton thread for the mantles, for it is solid, not hollow, more uniform in quality and continuous instead of being broken up into one-inch fibers. There is a great deal of difference in the quality of these mantles, as every one who has used them knows. Some that give a bright glow at first with the gas-c.o.c.k only half open will soon break up or grow dull and require more gas to get any kind of a light out of them. Others will last long and grow better to the last. Slight impurities in the earths or the gas will speedily spoil the light. The best results are obtained from a mixture of 99 parts thoria and 1 part ceria. It is the ceria that gives the light, yet a little more of it will lower the luminosity.

The non-chemical reader is apt to be confused by the strange names and their varied terminations, but he need not be when he learns that the new metals are given names ending in _-um_, such as sodium, cerium, thorium, and that their oxides (compounds with oxygen, the earths) are given the termination _-a_, like soda, ceria, thoria. So when he sees a name ending in _-um_ let him picture to himself a metal, any metal since they mostly look alike, lead or silver, for example. And when he comes across a name ending in _-a_ he may imagine a white powder like lime.

Thorium, for instance, is, as its name implies, a metal named after the thunder G.o.d Thor, to whom we dedicate one day in each week, Thursday.

Cerium gets its name from the Roman G.o.ddess of agriculture by way of the asteroid.

The chief sources of the material for the Welsbach burners is mon.a.z.ite, a glittering yellow sand composed of phosphate of cerium with some 5 per cent. of thorium. In 1916 the United States imported 2,500,000 pounds of mon.a.z.ite from Brazil and India, most of which used to go to Germany. In 1895 we got over a million and a half pounds from the Carolinas, but the foreign sand is richer and cheaper. The price of the salts of the rare metals fluctuates wildly. In 1895 thorium nitrate sold at $200 a pound; in 1913 it fell to $2.60, and in 1916 it rose to $8.

Since the mon.a.z.ite contains more cerium than thorium and the mantles made from it contain more thorium than cerium, there is a superfluity of cerium. The manufacturers give away a pound of cerium salts with every purchase of a hundred pounds of thorium salts. It annoyed Welsbach to see the cerium residues thrown away and acc.u.mulating around his mantle factory, so he set out to find some use for it. He reduced the mixed earths to a metallic form and found that it gave off a shower of sparks when scratched. An alloy of cerium with 30 or 35 per cent. of iron proved the best and was put on the market in the form of automatic lighters. A big business was soon built up in Austria on the basis of this obscure chemical element rescued from the dump-heap. The sale of the cerite lighters in France threatened to upset the finances of the republic, which derived large revenue from its monopoly of match-making, so the French Government imposed a tax upon every man who carried one.

American tourists who bought these lighters in Germany used to be much annoyed at being held up on the French frontier and compelled to take out a license. During the war the cerium sparklers were much used in the trenches for lighting cigarettes, but--as those who have seen "The Better 'Ole" will know--they sometimes fail to strike fire. Auer-metal or cerium-iron alloy was used in munitions to ignite hand grenades and to blazon the flight of trailer sh.e.l.ls. There are many other pyrophoric (light-producing) alloys, including steel, which our ancestors used with flint before matches and percussion caps were invented.

There are more than fifty metals known and not half of them have come into common use, so there is still plenty of room for the expansion of the science of metallurgy. If the reader has not forgotten his arithmetic of permutations he can calculate how many different alloys may be formed by varying the combinations and proportions of these fifty. We have seen how quickly elements formerly known only to chemists--and to some of them known only by name--have become indispensable in our daily life. Any one of those still unutilized may be found to have peculiar properties that fit it for filling a long unfelt want in modern civilization.

Who, for instance, will find a use for gallium, the metal of France? It was described in 1869 by Mendeleef in advance of its advent and has been known in person since 1875, but has not yet been set to work. It is such a remarkable metal that it must be good for something. If you saw it in a museum case on a cold day you might take it to be a piece of aluminum, but if the curator let you hold it in your hand--which he won't--it would melt and run over the floor like mercury. The melting point is 87 Fahr. It might be used in thermometers for measuring temperatures above the boiling point of mercury were it not for the peculiar fact that gallium wets gla.s.s so it sticks to the side of the tube instead of forming a clear convex curve on top like mercury.

Then there is columbium, the American metal. It is strange that an element named after Columbia should prove so impractical. Columbium is a metal closely resembling tantalum and tantalum found a use as electric light filaments. A columbium lamp should appeal to our patriotism.

The so-called "rare elements" are really abundant enough considering the earth's crust as a whole, though they are so thinly scattered that they are usually overlooked and hard to extract. But whenever one of them is found valuable it is soon found available. A systematic search generally reveals it somewhere in sufficient quant.i.ty to be worked. Who, then, will be the first to discover a use for indium, germanium, terbium, thulium, lanthanum, neodymium, scandium, samarium and others as unknown to us as tungsten was to our fathers?

As evidence of the statement that it does not matter how rare an element may be it will come into common use if it is found to be commonly useful, we may refer to radium. A good rich specimen of radium ore, pitchblende, may contain as much, as one part in 4,000,000. Madame Curie, the brilliant Polish Parisian, had to work for years before she could prove to the world that such an element existed and for years afterwards before she could get the metal out. Yet now we can all afford a bit of radium to light up our watch dials in the dark. The amount needed for this is infinitesimal. If it were more it would scorch our skins, for radium is an element in eruption. The atom throws off corpuscles at intervals as a Roman candle throws off blazing b.a.l.l.s. Some of these particles, the alpha rays, are atoms of another element, helium, charged with positive electricity and are ejected with a velocity of 18,000 miles a second. Some of them, the beta rays, are negative electrons, only about one seven-thousandth the size of the others, but are ejected with almost the speed of light, 186,000 miles a second. If one of the alpha projectiles strikes a slice of zinc sulfide it makes a splash of light big enough to be seen with a microscope, so we can now follow the flight of a single atom. The luminous watch dials consist of a coating of zinc sulfide under continual bombardment by the radium projectiles. Sir William Crookes invented this radium light apparatus and called it a "spinthariscope," which is Greek for "spark-seer."

Evidently if radium is so wasteful of its substance it cannot last forever nor could it have forever existed. The elements then ate not necessarily eternal and immutable, as used to be supposed. They have a natural length of life; they are born and die and propagate, at least some of them do. Radium, for instance, is the offspring of ionium, which is the great-great-grandson of uranium, the heaviest of known elements. Putting this chemical genealogy into biblical language we might say: Uranium lived 5,000,000,000 years and begot Uranium X1, which lived 24.6 days and begot Uranium X2, which lived 69 seconds and begot Uranium 2, which lived 2,000,000 years and begot Ionium, which lived 200,000 years and begot Radium, which lived 1850 years and begot Niton, which lived 3.85 days and begot Radium A, which lived 3 minutes and begot Radium B, which lived 26.8 minutes and begot Radium C, which lived 19.5 minutes and begot Radium D, which lived 12 years and begot Radium E, which lived 5 days and begot Polonium, which lived 136 days and begot Lead.

The figures I have given are the times when half the parent substance has gone over into the next generation. It will be seen that the chemist is even more liberal in his allowance of longevity than was Moses with the patriarchs. It appears from the above that half of the radium in any given specimen will be transformed in about 2000 years. Half of what is left will disappear in the next 2000 years, half of that in the next 2000 and so on. The reader can figure out for himself when it will all be gone. He will then have the answer to the old Eleatic conundrum of when Achilles will overtake the tortoise. But we may say that after 100,000 years there would not be left any radium worth mentioning, or in other words practically all the radium now in existence is younger than the human race. The lead that is found in uranium and has presumably descended from uranium, behaves like other lead but is lighter. Its atomic weight is only 206, while ordinary lead weighs 207. It appears then that the same chemical element may have different atomic weights according to its ancestry, while on the other hand different chemical elements may have the same atomic weight. This would have seemed shocking heresy to the chemists of the last century, who prided themselves on the immutability of the elements and did not take into consideration their past life or heredity. The study of these radioactive elements has led to a new atomic theory. I suppose most of us in our youth used to imagine the atom as a little round hard ball, but now it is conceived as a sort of solar system with an electropositive nucleus acting as the sun and negative electrons revolving around it like the planets. The number of free positive electrons in the nucleus varies from one in hydrogen to 92 in uranium.

This leaves room for 92 possible elements and of these all but six are more or less certainly known and definitely placed in the scheme. The atom of uranium, weighing 238 times the atom of hydrogen, is the heaviest known and therefore the ultimate limit of the elements, though it is possible that elements may be found beyond it just as the planet Neptune was discovered outside the orbit of Ura.n.u.s. Considering the position of uranium and its numerous progeny as mentioned above, it is quite appropriate that this element should bear the name of the father of all the G.o.ds.

In these radioactive elements we have come upon sources of energy such as was never dreamed of in our philosophy. The most striking peculiarity of radium is that it is always a little warmer than its surroundings, no matter how warm these may be. Slowly, spontaneously and continuously, it decomposes and we know no way of hastening or of checking it. Whether it is cooled in liquefied air or heated to its melting point the change goes on just the same. An ounce of radium salt will give out enough heat in one hour to melt an ounce of ice and in the next hour will raise this water to the boiling point, and so on again and again without cessation for years, a fire without fuel, a realization of the philosopher's lamp that the alchemists sought in vain. The total energy so emitted is millions of times greater than that produced by any chemical combination such as the union of oxygen and hydrogen to form water. From the heavy white salt there is continually rising a faint fire-mist like the will-o'-the-wisp over a swamp. This gas is known as the emanation or niton, "the s.h.i.+ning one." A pound of niton would give off energy at the rate of 23,000 horsepower; fine stuff to run a steamer, one would think, but we must remember that it does not last. By the sixth day the power would have fallen off by half. Besides, no one would dare to serve as engineer, for the radiation will rot away the flesh of a living man who comes near it, causing gnawing ulcers or curing them. It will not only break down the complex and delicate molecules of organic matter but will attack the atom itself, changing, it is believed, one element into another, again the fulfilment of a dream of the alchemists. And its rays, unseen and unfelt by us, are yet strong enough to penetrate an armorplate and photograph what is behind it.

But radium is not the most mysterious of the elements but the least so.

It is giving out the secret that the other elements have kept. It suggests to us that all the other elements in proportion to their weight have concealed within them similar stores of energy. Astronomers have long dazzled our imaginations by calculating the horsepower of the world, making us feel cheap in talking about our steam engines and dynamos when a minutest fraction of the waste dynamic energy of the solar system would make us all as rich as millionaires. But the heavenly bodies are too big for us to utilize in this practical fas.h.i.+on.

And now the chemists have become as exasperating as the astronomers, for they give us a glimpse of incalculable wealth in the meanest substance.

For wealth is measured by the available energy of the world, and if a few ounces of anything would drive an engine or manufacture nitrogenous fertilizer from the air all our troubles would be over. Kipling in his sketch, "With the Night Mail," and Wells in his novel, "The World Set Free," stretched their imaginations in trying to tell us what it would mean to have command of this power, but they are a little hazy in their descriptions of the machinery by which it is utilized. The atom is as much beyond our reach as the moon. We cannot rob its vault of the treasure.

READING REFERENCES

The foregoing pages will not have achieved their aim unless their readers have become sufficiently interested in the developments of industrial chemistry to desire to pursue the subject further in some of its branches. a.s.suming such interest has been aroused, I am giving below a few references to books and articles which may serve to set the reader upon the right track for additional information. To follow the rapid progress of applied science it is necessary to read continuously such periodicals as the _Journal of Industrial and Engineering Chemistry_ (New York), _Metallurgical and Chemical Engineering_ (New York), _Journal of the Society of Chemical Industry_ (London), _Chemical Abstracts_ (published by the American Chemical Society, Easton, Pa.), and the various journals devoted to special trades. The reader may need to be reminded that the United States Government publishes for free distribution or at low price annual volumes or special reports dealing with science and industry. Among these may be mentioned "Yearbook of the Department of Agriculture"; "Mineral Resources of the United States,"

published by the United States Geological Survey in two annual volumes, Vol. I on the metals and Vol. II on the non-metals; the "Annual Report of the Smithsonian Inst.i.tution," containing selected articles on pure and applied science; the daily "Commerce Reports" and special bulletins of Department of Commerce. Write for lists of publications of these departments.

The following books on industrial chemistry in general are recommended for reading and reference: "The Chemistry of Commerce" and "Some Chemical Problems of To-Day" by Robert Kennedy Duncan (Harpers, N.Y.), "Modern Chemistry and Its Wonders" by Martin (Van Nostrand), "Chemical Discovery and Invention in the Twentieth Century" by Sir William A.

Tilden (Dutton, N.Y.), "Discoveries and Inventions of the Twentieth Century" by Edward Cressy (Dutton), "Industrial Chemistry" by Allen Rogers (Van Nostrand).

"Everyman's Chemistry" by Ellwood Hendrick (Harpers, Modern Science Series) is written in a lively style and a.s.sumes no previous knowledge of chemistry from the reader. The chapters on cellulose, gums, sugars and oils are particularly interesting. "Chemistry of Familiar Things" by S.S. Sadtler (Lippincott) is both comprehensive and comprehensible.

The following are intended for young readers but are not to be despised by their elders who may wish to start in on an easy up-grade: "Chemistry of Common Things" (Allyn & Bacon, Boston) is a popular high school text-book but differing from most text-books in being readable and attractive. Its descriptions of industrial processes are brief but clear. The "Achievements of Chemical Science" by James C. Philip (Macmillan) is a handy little book, easy reading for pupils.

"Introduction to the Study of Science" by W.P. Smith and E.G. Jewett (Macmillan) touches upon chemical topics in a simple way.

On the history of commerce and the effect of inventions on society the following t.i.tles may be suggested: "Outlines of Industrial History" by E. Cressy (Macmillan); "The Origin of Invention," a study of primitive industry, by O.T. Mason (Scribner); "The Romance of Commerce" by Gordon Selbridge (Lane); "Industrial and Commercial Geography" or "Commerce and Industry" by J. Russell Smith (Holt); "Handbook of Commercial Geography"

by G.G. Chisholm (Longmans).

The newer theories of chemistry and the const.i.tution of the atom are explained in "The Realities of Modern Science" by John Mills (Macmillan), and "The Electron" by R.A. Millikan (University of Chicago Press), but both require a knowledge of mathematics. The little book on "Matter and Energy" by Frederick Soddy (Holt) is better adapted to the general reader. The most recent text-book is the "Introduction to General Chemistry" by H.N. McCoy and E.M. Terry. (Chicago, 1919.)

CHAPTER II

The reader who may be interested in following up this subject will find references to all the literature in the summary by Helen R. Hosmer, of the Research Laboratory of the General Electric Company, in the _Journal of Industrial and Engineering Chemistry_, New York, for April, 1917.

Bucher's paper may be found in the same journal for March, and the issue for September contains a full report of the action of U.S. Government and a comparison of the various processes. Send fifteen cents to the U.S. Department of Commerce (or to the nearest custom house) for Bulletin No. 52, Special Agents Series on "Utilization of Atmospheric Nitrogen" by T.H. Norton. The Smithsonian Inst.i.tution of Was.h.i.+ngton has issued a pamphlet on "Sources of Nitrogen Compounds in the United States." In the 1913 report of the Smithsonian Inst.i.tution there are two fine articles on this subject: "The Manufacture of Nitrates from the Atmosphere" and "The Distribution of Mankind," which discusses Sir William Crookes' prediction of the exhaustion of wheat land. The D. Van Nostrand Co., New York, publishes a monograph on "Fixation of Atmospheric Nitrogen" by J. Knox, also "TNT and Other Nitrotoluenes" by G.C. Smith. The American Cyanamid Company, New York, gives out some attractive literature on their process.

"American Munitions 1917-1918," the report of Benedict Crowell, Director of Munitions, to the Secretary of War, gives a fully ill.u.s.trated account of the manufacture of arms, explosives and toxic gases. Our war experience in the "Oxidation of Ammonia" is told by C.L. Parsons in _Journal of Industrial and Engineering Chemistry_, June, 1919, and various other articles on the government munition work appeared in the same journal in the first half of 1919. "The Muscle Shoals Nitrate Plant" in _Chemical and Metallurgical Engineering_, January, 1919.

CHAPTER III

The Department of Agriculture or your congressman will send you literature on the production and use of fertilizers. From your state agricultural experiment station you can procure information as to local needs and products. Consult the articles on potash salts and phosphate rock in the latest volume of "Mineral Resources of the United States,"

Part II Non-Metals (published free by the U.S. Geological Survey). Also consult the latest Yearbook of the Department of Agriculture. For self-instruction, problems and experiments get "Extension Course in Soils," Bulletin No. 355, U.S. Dept. of Agric. A list of all government publications on "Soil and Fertilizers" is sent free by Superintendent of Doc.u.ments, Was.h.i.+ngton. The _Journal of Industrial and Engineering Chemistry_ for July, 1917, publishes an article by W.C. Ebaugh on "Potash and a World Emergency," and various articles on American sources of potash appeared in the same _Journal_ October, 1918, and February, 1918. Bulletin 102, Part 2, of the United States National Museum contains an interpretation of the fertilizer situation in 1917 by J.E.

Poque. On new potash deposits in Alsace and elsewhere see _Scientific American Supplement_, September 14, 1918.

CHAPTER IV

Send ten cents to the Department of Commerce, Was.h.i.+ngton, for "Dyestuffs for American Textile and Other Industries," by Thomas H. Norton, Special Agents' Series, No. 96. A more technical bulletin by the same author is "Artificial Dyestuffs Used in the United States," Special Agents' Series, No. 121, thirty cents. "Dyestuff Situation in U.S.,"

Special Agents' Series, No. 111, five cents. "Coal-Tar Products," by H.G. Porter, Technical Paper 89, Bureau of Mines, Department of the Interior, five cents. "Wealth in Waste," by Waldemar Kaempfert, _McClure's_, April, 1917. "The Evolution of Artificial Dyestuffs," by Thomas H. Norton, _Scientific American_, July 21, 1917. "Germany's Commercial Preparedness for Peace," by James Armstrong, _Scientific American_, January 29, 1916. "The Conquest of Commerce" and "American Made," by Edwin E. Slosson in _The Independent_ of September 6 and October 11, 1915. The H. Koppers Company, Pittsburgh, give out an ill.u.s.trated pamphlet on their "By-Product c.o.ke and Gas Ovens." The addresses delivered during the war on "The Aniline Color, Dyestuff and Chemical Conditions," by I.F. Stone, president of the National Aniline and Chemical Company, have been collected in a volume by the author. For "Dyestuffs as Medicinal Agents" by G. Heyl, see _Color Trade Journal_, vol. 4, p. 73, 1919. "The Chemistry of Synthetic Drugs" by Percy May, and "Color in Relation to Chemical Const.i.tution" by E.R. Watson are published in Longmans' "Monographs on Industrial Chemistry." "Enemy Property in the United States" by A. Mitch.e.l.l Palmer in _Sat.u.r.day Evening Post_, July 19, 1919, tells of how Germany monopolized chemical industry. "The Carbonization of Coal" by V.B. Lewis (Van Nostrand, 1912). "Research in the Tar Dye Industry" by B.C. Hesse in _Journal of Industrial and Engineering Chemistry_, September, 1916.

Kekule tells how he discovered the const.i.tution of benzene in the _Berichte der Deutschen chemischen Gesellschaft_, V. XXIII, I, p. 1306.

I have quoted it with some other instances of dream discoveries in _The Independent_ of Jan. 26, 1918. Even this innocent scientific vision has not escaped the foul touch of the Freudians. Dr. Alfred Robitsek in "Symbolisches Denken in der chemischen Forschung," _Imago_, V. I, p. 83, has deduced from it that Kekule was morally guilty of the crime of OEdipus as well as minor misdemeanors.

CHAPTER V

Read up on the methods of extracting perfumes from flowers in any encyclopedia or in Duncan's "Chemistry of Commerce" or Tilden's "Chemical Discovery in the Twentieth Century" or Rogers' "Industrial Chemistry."

The pamphlet containing a synopsis of the lectures by the late Alois von Isakovics on "Synthetic Perfumes and Flavors," published by the Synfleur Scientific Laboratories, Monticello, New York, is immensely interesting.