Page:Popular Science Monthly Volume 92.djvu/395

 Popular Science Monthly 379

Identification Tag of Indestructible The War Is Causing a Decrease in Metal for Naval Men the Number of Lunatics

���THE difficulty of finding a simple and adequate method of identifying soldiers or sailors who are killed or seriously in- jured in the course of war oper - tions, has been solved by J. H. Taylor, of Alexandria, Va., by the invention of an identification tag which was adopted by the U. S. Navy Department on May 12, 1917. The tag, which is considered the best in use in any country in the world, consists of a plate of Monel metal, which does not melt below a tempera- ture of 3840 de- grees Fahrenheit and is not corroded by salt water. The name of the bearer and other data are written with diluted printer's ink on. one side of the tag, while a rolled impression of the bearer's right in- dex finger is placed on the opposite side. The tag is then dipped in asphaltum and the superfluous asphaltum removed with a fine brush, after which it is heated until the ink on both sides is glossy. After cooling the tag is deposited in a nitric- hydrochloric acid bath which etches the

surface of the

metal not cov- f ered by ink. By means of a string or chain passed through a hole in it the completed disk is carried arou nd the neck of the wearer upon all occasions, in the same man- ner as a charm, for it takes up no room and is put on and forgotten.

��EVIDENTLY a great na- tional struggle makes for mental steadiness. For the past two years there has been a decrease of over three thou- sand in the number of insane persons cared for in England and Wales. This fact is thought- provoking because be- fore the war the yearly statistics showed a constantly increasing number of lunatics.

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��This naval identification tag only melts in the most intense heat and is not cor- roded by salt water, being of Monel metal

��B. F.

��Rolling Roads with Gaspipe

SIMPLE method for compacting the sur- face of concrete roads and removing excess water has been evolved by an Batchelder, of Ravenna,

���A piece of ordinary gaspipe is successfully used as a roller to remove excess water from the road surfaces

��engmeer, Ohio.

After striking off the surface with a template, according to Mr. Batchelder's plan, a piece of ordinary gaspipe, operated by two men, is used as a roller. After the excess water has come to the surface, another trip up and back with the roller removes all the water and leaves the sur- face in good condition for further finishing

if necessary. A wave of mor- tar is carried ahead of the roller the "first time over," which fills in porous placesor depressions. The second rolling removes nothing but water that is virtually clear. This method is especially useful when using crushed stone or slag.

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