From the January 2, 1932 issue

CONCRETE RIBBONS TO CARRY TRAFFIC OF GREAT HIGHWAY

Thin ribbons of concrete arching through the air, that will carry on a 42-foot wide pavement, traffic of one of the countrys chief east-west thoroughfares, the Lincoln highway, are skillfully depicted in this photograph of the George Westinghouse Memorial bridge nearing completion at East Pittsburgh.

The arches are more than half again as thin as those usually used. Their width is fourteen feet, and they are five feet thick at the top or crown, and ten feet through at the ends, or springings.

PREVENTION OF TOOTH DECAY ACCOMPLISHED FOR FIRST TIME

For the first time in history, dental caries or tooth decay has actually been prevented. This means that the end of toothaches and of rotting, decayed and infected teeth, with their attendant ills, is now in sight. The method found effective to prevent tooth decay in animals need only be applied to human beings.

This achievement, the result of ten years of work with hundreds of animals and representing an immeasurable boon to mankind, has been accomplished by Dr. E.V. McCollum, professor of biochemistry at the Johns Hopkins School of Hygiene and Public Health, and his associates, Dr. Henry Klein and Dr. H.G. Kruse.

The quality of the saliva is the important thing in determining whether teeth will decay and this is determined by the chemical composition of the blood, says Dr. McCollum.

The saliva, he has found, acts normally as a buffer solution so that acid cannot accumulate and break down the enamel of the teeth. When this enamel is damaged, germs that are always present in the mouth get a chance at the teeth and decay follows. The saliva, however, cannot act as a buffer solution, keeping the mouth at just the right state between acid and alkaline, unless it contains a certain proportion of phosphorus. There must be, in addition to a proper buffer quality for neutralizing acid formed by the fermentation of food residue, a proper calcium and phosphate ion concentration in the saliva in contact with the enamel to prevent disintegration of the surface molecules of that substance.

Phosphorus gets into the saliva from the blood. Blood gets its phosphorus from the foods eaten, specifically from such foods as milk, eggs, lean beef, beans and peas, which are rich in phosphorus.

Phosphorus is not quite all that is needed, however. Dr. McCollum and his associates found that no matter how much phosphorus is eaten in food, not enough of it will get into the blood and then into the saliva unless a certain amount of both calcium and vitamin D are also taken into the body.

SPLITTING OF PRIMEVAL STAR MAY HAVE MADE SOLAR SYSTEM

A new theory of the formation of the solar system and the Earth by the whirling of a great primeval star into two fragments, one the sun and the other its lost twin, was presented to science by Dr. Ross Gunn of the U.S. Naval Research Laboratory, speaking before the American Astronomical Society meeting at Washington.

The following consequences are implied:

1. There are thousands of other planetary systems in the universe, some of which may have life not unlike that on the Earth.

2. The Earth was born of a rather common occurrence in the heavens, not the rare accident of the collision of two stars.

3. The birth of the solar system resulted from a definite, orderly and evolutionary plan, which was largely guided by electric and magnetic forces.

This new skyrocket theory of the origin of the Earth is intended to supersede the Sir James Jean-Dr. Harold Jeffreys version of the planetesimal hypothesis advanced by the late Prof. T.C. Chamberlin and Dr. F.R. Moulton, American scientists. This considers that a massive star came so close to the sun that it extracted the planetary system by tidal action.

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