Convening Chemists

A one-pound ball of the fibre, if straightened out, would stretch from coast to coast of the U. S. A woman's undergarment made of it could be concealed in the palm of the hand. It is 150% finer than any previous rayon, 33% finer than natural silk. It was developed almost simultaneously by three manufacturers and no one has an exclusive claim to it.

Such were the facts about a new synthetic fibre, recited last week in Kansas City, by Dr. Ernest Baden Benger of du Pont de Nemours & Co. Nearly 2,000 chemists, some of them from England, Switzerland and Holland, were assembled there for the 91st convention of the American Chemical Society.

Rubber, silk, cellulose and certain other organic compounds contain "giant molecules" weighing hundreds of thousands and even millions of times as much as the hydrogen atom. The rayon industry (which last year produced more than 256,000,000 lb. of fabrics, employed 60,000 workers and paid them $60,000,000) is currently profiting by a clearer understanding of these mammoth particles. It has been found that cellulose molecules in cotton are chains of 3,500 links. Such long molecules could be seen under the microscope if they were fat enough. The new artificial fibre is built on the same plan but limited to 450 links. Dr. Benger declared it would make cooler and cheaper summer clothes.

Other noteworthy discussions of the meeting:

Flame & Pressure. General Motors Corp. has developed an ingenious camera arrangement which takes 5,000 pictures per second of the fuel explosion in an automobile motor combustion chamber. When a car is bowling along at 40 m. p. h., its motor turns over about 2,000 times a minute, and one complete explosion lasts only 1/250th of a second. Of this brief performance the camera records 20 successive stages. The film runs continuously at crankshaft speed--up to 250 m. p. h. Light from the explosion passes through a heavy quartz window in the cylinder head to a stationary lens, thence to a series of 30 rapidly moving lenses which follow the film and hold each image motionless on it during exposure. The spark is seen first like a lone star in a black sky, then a flame front spreading and backwashing around the base of the chamber. At one stage back pressure was observed to make combustion-produced carbon dioxide hotter than the actually burning gases. Pressure-curve recorders enable motormen to cor relate pressure with flame front propagation, a long-sought goal.-- Dr. Gerald Mark Rassweiler and Lloyd Withrow of GM's Detroit laboratories.

Molecule Magnets. It has been known for years that nerve impulses are electric in nature. But the mode of transmission remained obscure. It was wrong to picture a current passing along a nerve fibre as if through a metallic conductor. Since 1926 Dr. Edwin Joseph Colin and his associates at Harvard have been looking for a better picture. Last week he announced important progress.

Some "giant molecules" of organic tissue are so long that, although their net charge is zero or nearly zero, the positive charge is concentrated at one end, the negative at the other end. The distance between them is a factor in the dipole moment, which is, roughly speaking, a measure of electric leverage. Dr. Cohn measured the charges and the dipole moments by observing molecular behavior under a bombardment of radio waves. If some stimulus discharged the positive tension at one end, the negative charge would redistribute itself, affecting other molecules. If these molecules twitched in response to the charge, their movements would generate a current affecting still other molecules. Thus, like a row of falling dominoes, the molecules in the nerve tissue might electrically hand on an impulse from beginning to end of the nerve arc. "Clarification of these effects removes an important barrier to the . . . intelligent treatment of nervous disorders."

Synthetic Atmospheres. Without oxygen animals smother; in pure oxygen they die also because of irritation and congestion in the lungs. Yet it must not be assumed that the best possible mixture for sustaining life is the natural atmospheric mixture of about 79% nitrogen, 20% oxygen and 1% other gases. After twelve years of smothering rats, monkeys and guinea pigs in various artificial atmospheres ranging from pure helium to nitrous oxide, Dr. John Willard Hershey of McPherson College reported that a mixture of 75% argon and 25% oxygen enabled the animals to get along as well as usual, that in 50% helium and 50% oxygen they were apparently more healthy and vigorous than in natural air.

CO Antidote. Rats were poisoned by carbon monoxide to the point of cyanosis and respiratory convulsions. When hexahydroxyferric chloride (a reaction product of ferric chloride and hydrogen peroxide) was injected into their bellies, 75% recovered.--Sam & Joseph Seifter of University of Oklahoma's School of Medicine.

Alcohol v. Gasoline. Because alcohol can be distilled from surplus agricultural products, alcohol-gasoline blends for motor fuel are closely linked with legislative aid to farmers. Some European states have made alcohol mixtures mandatory. In the U. S. alcoholic gasoline is a subject of controversy among fuel chemists, their views depending on whether their allegiance is to farm or refinery. Completely contradictory statements on alcohol blends were uttered from the same platform last week by Leo Martin Christensen of the Farm Chemurgic Council and Dr. Gustav Egloff of Universal Oil Products Co.

Christensen: Alcohol-gasoline blends distributed in the Midwest during the past three years have met with excellent consumer response. Better mileage, improved acceleration, practical elimination of gum and carbon deposition, smoother and more pleasing engine operation have been . . . commonly reported.

Egloff: Alcohol-gasoline is a distinctly inferior motor fuel in performance, consumption and upkeep of motor. Difficult starting, slow acceleration,'over-heating of engines, and rougher driving can be expected.

Christensen: Alcohol-gasoline blends are no more corrosive to any engine part than is gasoline.

Egloff: Increased maintenance cost will result from cylinder and valve wear, all-around corrosion, plugging fuel lines and dissolving of car varnish.

A presumably neutral view from Yale, which has neither farms nor oilwells, was injected by Lester Clyde Lichty and E. J. Ziurys: "The fuel economies accompanying the increased compression ratios made possible by the use of alcohol are offset, both theoretically and from engine test, by its lower heating value per pound of fuel. ... It requires about 1.67 lb. of alcohol to liberate the same amount of energy as . . . by one pound of gasoline."

Explosive from Corn, Professor Edward Bartow, president of the American Chemical Society, has 25 lb. of inositol which he keeps locked in a safe at University of Iowa. Inositol is an alcohol which occurs exiguously in the seeds of certain plants. Treated with nitric acid it forms a solid substance about twice as explosive as dynamite. Inositol has been so difficult to extract that only about 5 lb. are produced annually and the price is $500 per lb. Professor Bartow and his able associate, Dr. W. W. Walker, found a way to extract inositol from the water in which corn is soaked to make cornstarch. The 300,000,000 quarts of this "steep water" which the cornstarch industry throws away every year would yield by the Bartow-Walker extraction method 1,000,000 lb. of inositol at low cost. Final details of the process have been worked out in the past two months. "Until that time," said Dr. Bartow last week, "it was just a dream with me, and it still seems like a dream."

Prize for Promise. The Langmuir Prize of $1,000 is awarded annually by the society to a chemist under 30 years of age who shows promise of an exceptionally brilliant career. Last week's winner was John Gamble Kirkwood, who was born in Gotebo, Okla. 29 years ago, got his Ph. D. at 23 from Massachusetts Institute of Technology, and is now an assistant professor at Cornell. Of little interest to laymen, Dr. Kirkwood's work on the dielectric properties of gases under pressure and on polarization phenomena in methane, nitrogen and hydrogen provided invaluable working tools for chemists. Said the award committee: "He succeeded in instances where older and more experienced men of proved ability have failed to arrive at definite results."

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