Page:Popular Science Monthly Volume 92.djvu/83

 Popular Science Monthly 67

Bubbles in the Blood Kill Many No Trouble if This Mirror Drops. It a Poor Soldier Is of Indestructible Steel

��SOLDI found

��ERS are

���A small steel mirror for the trenches. With it a soldier can shave perfectly

��the battlefield, with no mark of an injury. Some are Ijnng with arms outstretched as in running; others are grasping their guns as though about to fire — all are in ex- actly the positions in which they were at the moment of death. These mysterious deaths do not occur as a result of nervous shock; else the bod- ies would be relaxed and natural. They are victims of "the bends" or "caisson disease" caused by sudden release from great air-pressure.

When a workman emerges from a high- pressure air chamber, his blood fills with small bubbles, like those of champagne when first uncorked. If the bubbles are large enough to choke the circulation, the man dies. On the battlefield, such occur- rences are the result of intense explosion- waves. The blood holds in solution a con- siderable amount of air and carbon dioxide, the quantities being greater when the pressure is high.

Upon lowering the pressure, the gases sep- arate out as bubbles. In the case of soda water, the bubbles can escape, but in a man they are caught in the capillaries. All mus- cular action is arrested with lightning-like rapidity, thus preserv- ing the attitude held

by the victim before just rub the tobacco off the

the fatal attack. windshield with a clean cloth

��A THREE by four inch mirror, which is intended especially for use in the trenches, is made of a special metal which contains a high percentage of nickel. It will neither rust not corrode.

The surface of the metal is highly pol- ished and reflects al- most as well as glass. It is protected by a soft lined case into which it fits.

It is usually car- ried in the upper left hand coat pocket, where it does excel- lent service as a shield, being suffi- ciently strong to di- vert glancing bullets.

���Chewing-Tobacco to Clear \^ ind- shields! Would You Believe It?

WHILE inventors are trying to devise something that will effectually pre- vent the fogging of automobile wind- shields in rainy weath- er, along comes Theo- dore Petersen, a drug- gist in Grand Rapids, Michigan, with a plug of ordinary chewing tobacco and solves the whole problem!

Not only does the tobacco prevent the windshield from fogging, he says, but it enables the rain water to run off the glass without collect- ing in drops. After each application it is only necessary to rub off the glass with a cloth to remove all marks of the tobacco.

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