VOL. 9, NO. 2
ABSTRACTS
373
only has there been a shortage of water in many states, hut the quality of that which was secured was dangerous. The state of Kentucky alone sent out typhoid serum for a million people. The serum attacked germs after they entered man's body, while ultraviolet light, ozone, and chlorine attacked them before entry. B. C. H. The effect of sunlight upon man. J. H. P o n s . . Phi Della Kappan, 14, 29.42 (June, ,l931).-Beginning with a brief reference t o the history of man's earhest conscious apprecutlon of sunlight theauthor continues by an account of the very obvious response of plant life to solar radiattun. A s uuulrl be expected, tnajor attention i given to man's mowing llnderstanding of the relntlun of sunlirht to health. Amunr the value.; of sunlight en~nnerntedin t h i ~ connection are: its relation t o calcium andphosphorus metaboli&, its destructive effect upon bacteria, its toning effect upon muscles and its more than tanning effect upon the skin. Of special intcrest to the chemist is the account of the relation of ultra-violet radia. tion upon foods to their vitamin content and how vitstnin D eRrrts nre forthcoming frotn foods so treated. How rod-liver oil "gets its sunlight" is another item of interest. B. C. H The sun an atom builder: a new theory. H. N. R n s s n ~ . Sci. Am., 145, s2-3 (Oct., 193l).-The sun sends out 4,200,000tons of heat every second and has been doing so for the thousand million years or more of geologic time. Whence the source of all this energy? The author comments briefly on older theories relating t o the origin of the sun's heat and then propounds the theory that a p r o w s of atom building is going on in the sun which may account for the sun's source of heat. The theory maintains that insufficient time has elapsed t o build up atoms heavier than sodium so that other factors C. M. P. must be a t work t o produce the heavier atoms.
Basis of Einstein relativity theory still stands. The foundations of the Einstein relativity theories have been in part reaffirmed by a repetition a t the Zeiss works a t Jena of the famous Michelson-Morley 1887 experiylent, the surprising result of which later stimulated Prof. Albert Einstein t o develop his theories. There is no "ether wind" flowing through the atmosmere because of the motion of earth through space. This deduction made by the late Prof. A. A. Michelson and his colleame from their experiment was again verified in Jena by Dr. G. Joos. Numerous repetitions of the Michelson-Morley experiment with a similar apparatus have been made by Prof. Dayton C. Miller of the Case School of Applied Science working hnth -. i t Cleveland and a t the Mount Wilson Observatory of the Carnegie Institution of --Washington. Dr. Miller has, however, detected a constant drift of the earth of about ten kilometers per second which. though only about a twentieth of the estimated velocity of the solar system through space, is in agreement with the original experiment of Michelson and Morley. The latter experimenters, contrary t o general belief, did not obtain an absolutely null result. No explanation of this small drift has yet been given. The experiment consists in trying t o detect a difference between the time required by a beam of light to travel between two points with the direction of the earth's motion and hack again as compared with the time of travel perpendicular t o the line of motion of the earth. The two beams are made t o interfere with each other and produce a characteristic pattern. Each of the four arms of the Joos apparatus, constructed with the coiiperation of the Zeiss Optical Company, was over two yards long. The whole was made of quartz glass and suspended on numerous fine springs. By the use of mirrors the total path of each ray in this interferometer was made 21 feet. Rotation of this apparatus through a right angle should, if there is an ether-drift, cause a shifting of the pattern. No movcment was observed.-Science Service ~~~~
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