ABSTRACTS 



Authors of scientific papers are requested to see that abstracts, preferably 

 prepared and sipied by themselves, are forwarded promptly to the editors. 

 The abstracts should conform in length and general style to those appearing in 

 this issue. 



PHYSICS. — The decrease in liUra-violet and total radiation ivitJi usage 

 of quartz mercury vapor lamps. W. W. Cobi^untz, M. B. Long, 

 and H. Kahler. Bur. Stands. Sci. Paper No. 330. Pp. 20. 

 1918. 



It is well known that the radiations emitted by quartz mercury vapor 

 lamps decrease very markedly in intensity with usage of the lamp. The 

 object of this investigation was (i) to devise methods for determining 

 quantitatively the decrease in intensity of the emission with usage and 

 (2) to make preliminary measurements on radiant power life-tests of 

 quartz mercury vapor lamps. 



The measurements of the radiations from these lamps were made 

 by means of a thermopile. The ultra-violet rays were absorbed by 

 means of a yellow glass and by this means it was possible to study the 

 decrease in the ultra-violet radiation as well as the decrease in total 

 radiation with tisage of the lamp. It was found the intensity of the 

 total radiation as well as the ultra-violet component, decreases to about 

 one-half of its initial value in the course of 1,000 to 1,500 hours. 



W. W. C. 



PHYSICS. — New Bamn^ scale for sugar solutions. Frrdrrick Bates 

 and H. W. BF;ARCii;. Bur. Stands. Tech. Paper No. 115. Pp. 

 II. 1918. 



Many different Baume Scales have been proposed and used in the 

 past. At the present time there are still in use in the United States 

 three different scales for liquids heavier than water. Two of these, 

 namely, the "Holland" scale and the "Gerlach" scale are used in sugar 

 work. Neither is adapted to modern requirements. The new scale 

 lies between the "Holland" and "Gerlach" scales and has three im- 

 portant advantages which should commend it for general use. They 

 are: 



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