Sound waves impair light measurements - Journal of Chemical

Sound waves impair light measurements. J. Chem. Educ. , 1927, 4 (9), p 1125. DOI: 10.1021/ed004p1125. Publication Date: September 1927. Cite this:J. C...
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VOL.4. NO.9 CRBMISTRY AS AN INSTRUMENT OF GBNBRAI. EDUCATION

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to fill some of the gaps left by a purely classical education, not only by imparting useful information about the world, but also by developing desirable mental and moral qualities. Methodical habits pursued for a whole year surely leave their unmistakable impress on the mind, and with very little difficulty they may be carried over into other subjects, where they soon prove their usefulness. Vigorous disciplme also teaches the great virtues of patience and sacrifice. The great, unforgettable lesson of moral responsibility, together with that of intellectual humility and the dignity of work, is planted so deeply that it can never be entirely uprooted. Last of all, chemistry kindles the flame of the love of truth, so that it burns with a clear light that can be extinguished only with difficulty. Because of all these facts, it is plain that no one can afford to neglect chemistry as an instrument of general education.

Sound Waves Impair Light Measurements. Sound waves from a motorcycle can hamper determination of whether the earth is drifting through the ether which is supposed to pervade all space, accordin to Dr. Dayton C. Miller of the Case School of Applied Science, who ha- been making a series of observations which may show the presence or absence of this ether. Two years ago, Dr. Miller repeated an experiment performed many years ago by Michelson and Morley. This was supposed t? show that the earth was drifting throu~hthe ether, but an almost negligible effect d s then ohtained. One of the consequences of the efforts to explain the result was the Einstein theory of relativity. However, when Dr. Miller repeated the experiment a t the Mt. Wilson Observatory in California, he found that there pias an appreciable effect. When he announced this before, i t was hailed a$proving that the earth was drifting through the ether and that it meant the downfall of the relativity theory. Other scientists since have tried the experiment without confirming Dr. Miller's results. Now he has set up the apparatus on the campus of the Case School and the first series of observations, which have just been completed, are completely in accordance with the Mt. Wilson results, be says. As an illustration of the delicacy of the measurements, Dr. Miller says that one objection seemed to he that the traffic on two nearby streets affected the sensitive fringes of light and darkness which the instrument reveals. This was overcome with a heavy concrete foundation, but there were still disturbing effects. It was finally found that a trolley car going by had no effect, but if a motorcycle started noisily two blocks away, the frinees . cam~letelv . . vanished. This proved to be due to the sound waves from the machine causing a variation in density of the air through which the light bad to pass, and so Drevented the aDDearance of the alternate bands of light and dark.-Science