SOUND WAVES

Evening Star, Issue 22277, 2 March 1936, Page 11

SOUND WAVES

ABLE TO CRUSH STEEL MATHEMATICS REVOLUTIONISED A description of sound waves powerful enough to crush steel, given by Dr L. Thompson, American naval proving ground expert, was only one of a series of startling revelations made before the ninety-seventh annual conference of the American Association for the Advancement of Science. A spot in the Arctic, where the cold, dry air is such an excellent conductor of sound that ordinary speech can be heard for 10 or 15 miles, was revealed by Dr Vein O, Knudsen, of the University of California at Los Angeles. And a prediction that the next decade would see development of mathematical robots, revolutionising this branch of physical science just as arithmetic was revolutionised by the mechanical abacus of olden times, came from Dr Vannevar Bush, vicepresident of the Massachusetts Institute of Technology. Further than this, two inventors from the Radio Corporation of America announced that they have perfected an eye by which man can see in the dark. This eye, looking like an over-sized light bulb, is really a vacuum tube on which infra-red and ultra-violet rays, invisible to natural sight, form an image that the observer may see by looking into a lens at the small end.

By this invention Drs V. K. Zworykin and George A. Morton say it will be possible for aeroplanes equipped with such a telescope to guide themselves to a secret landing port by the use of a “ black light ” beacon or infra-red ray. The two discoverers of this .telescope state that the ray is so invisible that it could not be seen by persons near it on the landing field.

Gold and silver were discussed from a scientific as well as monetary basis, and gold came off with first honours. For silver, stated Professor A. J. Dempster, of the University of Chicago, has two isotopes—or forms of the same element which differ only in the weight of the atoms. Thus, as silver is actually made up of two parts—light and heavy silver—they should be quoted on the market, he said, “at different prices per ounce.” But gold, Professor Dempster told the association, is the only safe monetary standard, as it is solidly and completely one element, not a twin. Dr Bush, in explaining the development of the new mathematical robots, asserted, however, that the abacus is still the most widely used mechanical computing machine. “An expert in its use can nearly keep up with the operator of an adding machine,” he said, “ and can multiply as well. No one knows its inventor. Originally, probably only a pile of pebbles arranged in groups, it developed into a form in which counters are strung on parallel rods or wires. The mechanical fact that it is convenient to mount rods or wires parallel to one another in a frame produced the idea that numbers should have definite sequence. The necessity for expressing the absence of counters gave us the zero.”

Among other papers delivered. Dr Frank H. Roberts, of the Smithsonian Institution of Washington, told of his recent discoveries of the culture of Folsom Man at the font of the Rockies in Colorado, and Dr Ferris F. Laune, sociologist at the Illinois State Penitentiary, outlined new tests being used at Joliet in the paroling of prisoners. Dr Bush spoke before the entire association, delivering its twelfth annual Josiah Gibbs lecture on the subject of ‘ Instrumental Analysis.’ He pointed out difficulties early mathematicians encountered because “ they _ were too high hat to use the abacus in connection with their profound meditations. “ They stuck to their cumbersome notations while men of trade, with a mechanical aid, produced the most farreaching of mathematical inventions. The formalists insisted that ruler and compass were the only tools worthy of the gentleman scholar, and by this insistence directed the attention of the learned for centuries to three impossible problems. Even to-day the race of angle trisectors has not died out,

although the problem was liquidated over a century ago.” Dr Bush covered three of the most modern “ math robots,” as well as ancient ones. The first was suggested by Professor Wiener of technology, and has proved useful for obtaining the product of two given functions. Its greatest use is for solving djfficult construction and engineering problems. The second equation solver is for the examination of complex electrical power networks, while the third solves simultaneous lines of algebraic equations—a most valuable time saver for the engineer. “The first piece of mathematical apparatus used,” according to Dr Bush, “ was the human hand. Nature supplied us with 10 fingers, and in the groping development of early mathematics, this settled the decimal system upon us. Our forbears apparently did their reckoning standing up, or we might have done as some other tribes do—count toes as well and thus land on the vicenary system. “ Had this occurred, it would have been possible to register all of New York’s automobiles with five figures, and Congress would have had to be satisfied with merely eight-figure appropriations. But it is also fortunate that at least both hands were used, or the newspapers would now be running out of zeros.”

Before assigning definite dates to the age of the Folsom culture, Dr Roberts is awaiting the decision of Dr Kirk Bryan, of Havard, who is studying the geology of the district in an effort to determine the age of the deposits. But, meanwhile, archmologists are generally agreed that these remains are the earliest of aboriginal culture yet discovered. With, delicate arrowheads, distinctively different from common southw'estern types, found in close association with the bones of extinct animals, Dr Roberts feels he has good reason to date man in North America at the beginning of the post-glacial period. The only other alternative is to postulate a later survival for Ice-Age animals than is generally believed probable. Dr Laune’s report on new parole methods at Joliet Penitentiary indicated that the public attitude toward modern parole systems is based on “ a misconception that parole constitutes a remission of part of the sentence of an offender. Such is far from the case,” he asserted. “ Parole is an added factor in which the conduct of the delinquent is controlled after his release from imprisonment. As over 90 per cent, of all persons in prison will be released according to law at some time, the important question is to determine when they should be released, what their chances are for making good, and whether such release is to be unconditional or under supervision.” By questionnaires filled in by parole applicants the Joliet parole board found there were five main causes for failure to make good on parole: The desire for fine clothes, dislike of relatives, interest in “ white lights,” tendency to sharp practices, and argumentativeness.

“ Our aim is to isolate those intrinsic character traits of the individual which tend to return him to prison, and correct them so that the same temptations are not overpowering another time.”