84 abstracts: chemistry 



small. (6) The received antenna currents between two stations are 

 proportional to the product of the heights of the sending and receiving 

 antennas and inversely proportional to the wave length, provided the 

 antenna resistances remain constant, (c) Taking account of the influ- 

 ence of antenna height and wave length equation (1) may be extended 

 and a general day transmission formula written as follows 



T h,h„ 00015 d 



(2) I K = 4.25^fe-vT- 



Act 



When I s is the sending antenna current, h antenna height and X the 

 wave length. The currents are given in amperes and all lengths in 

 kilometers. From this it would appear that it is advisable to rate sta- 

 tions according to the magnitude of the antenna current, or perhaps 

 better, according to the product of the current into the height. L. W. A. 



CHEMISTRY. — The behavior of high-boiling mineral oils on heating 

 in the air. C. E. Waters. Bulletin Bureau of Standards, 7, 

 365-376, 1911. Journal of Industrial and Engineering Chemis- 

 try, 3: 233. 1911. 



The oils were heated to 250° for three hours in Erlenmeyer flasks 

 which were placed in a special air-bath so arranged as to secure free 

 diffusion of air into them, as well as to allow the escape of volatile por- 

 tions of the oils. After cooling, the contents were diluted with petro- 

 leum ether and next day the insoluble "asphalt" was filtered off and 

 weighed. The insoluble matter was shown to be an oxidation product. 

 The amount formed was apparently independent of the amount of oil 

 evaporated. The latter, and also the amount of varnish-like coating 

 on the walls of the flasks, varied widely, but the amount of insoluble 

 matter was fairly constant. 



There seemed to be some evidence of catalytic action which influenced 

 the amount of insoluble and "varnish" formed. These were both 

 greater in amount when a second lot of oil was heated in a flask which 

 had not been cleaned after one heating. 



Three different oils were heated also in tubes of the same dimensions 

 made of glass, brass, chrome-vanadium steel, vanadium steel, cold- 

 rolled steel, cast iron and a steel containing 0.8 per cent carbon. For 

 two of the oils the percentages of insoluble formed were about the same 

 in all of the tubes, except those of brass, where the amount was much 

 greater. The third oil yielded less insoluble in the brass tubes than in 

 those of glass, and very much greater amounts in the chrome-vanadium 



