From the May 13, 1933, issue

RISING SILENTLY TO PROTECT NATIONS TIME

Almost as silently as you view the new domed building in the cover picture, this all-steel structure is rising at the U.S. Naval Observatory in Washington. There is no hammering of rivets to fray the nerves of humans and upset the accuracy of the delicate Naval Observatory clocks that regulate timepieces throughout the country.

Economy, rigidity of construction, and light-proof domes are also claimed as advantages of welding.

In addition to this building, 35 feet high and 33 feet in diameter, a smaller one 25 feet in height is being erected. The dark, curved steel piece in the foreground is the cover for the opening of the large dome.

These buildings are to house new 15- and 40-inch telescopes.

PASSING SOUND THROUGH GASES HELPS STUDY OF MOLECULES

It is lucky we do not live in an atmosphere of straight oxygen–at least in weather of desert humidity. We would not be able to hear sounds of high pitch at a considerable distance. Recent investigations carried out in the University of California at Los Angeles suggest that the excessive absorption of sound in air of certain humidities is due to collisions between oxygen and water molecules. Prof. Vern O. Knudsen described to the meeting of the Acoustical Society of America at Washington the Los Angeles experiments, in which Dr. H.O. Kneser, visiting physicist from the University of Marburg, cooperated.

Sound travels freely through chemically dried air, particularly at low temperatures, according to the electrical recording instruments of the California laboratory. Perhaps this accounts for the common opinion that audibility is keen on a clear, cold night. The introduction of small quantities of moisture promptly damps off the sound, especially tones of high pitch. Peculiarly, this phenomenon does not occur when pure nitrogen is substituted for the air, despite the fact that air is nearly 80 percent nitrogen. A shift to pure oxygen in the experiment reveals this latter gas as the guilty party. But oxygen alone is rather ineffective. Water vapor must also be present to affect the sound waves.

MANY COLORS FOUND IN EYES OF NEWBORN BABIES

The tradition that all babies’ eyes are blue at birth has been shattered. Taught by physicians, physiologists, and geneticists for many years, this “fact” has been proved a fallacy by the simple means of actually examining under good illumination the eyes of nearly 500 newborn infants in the hospital of the Johns Hopkins University. Dr. W.C. Beasley, instructor in psychology at the university, made the examination.

Not only were other colors than blue found in the newborn babies’ eyes, but brown was found in 79.5 percent of the white infants’ eyes and 99.3 percent of the Negroes’. Many eyes held several colors. Yellowish and reddish browns were seen, and greens, violet, gray, and lavender, as well as flecks and streaks of as many as 187 different hues. Only 28 of the 455 infants examined had plain blue eyes.

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