﻿'94 Canadian Record of Science. 



^scientific periodicals. The commercial carbide, unlike 

 that made by Moissan, probably contains compounds of 

 •calcium with the ash of coke, but no complete analysis 

 has been published. Some of the statements made about 

 .the number of cubic feet of acetylene are obviously 

 inaccurate, because the figures 5.89 to 6.35 cu. ft. acetyl- 

 *ene per 1 lb. carbide are as high or higher than could be 

 obtained if the carbide contained no ash and were abso- 

 lutely pure. 



The accurate measure of the gas given off by the car- 

 bide is not easy and requires the construction of a special 

 apparatus. The writer has examined a number of samples 

 «of commercial carbide, and found that 70 to 92 per cent, 

 vof the theoretical quantity of acetylene could be obtained 

 irom them. It appears that the product which can be 

 jnade to the best advantage is one which contains 84.6 

 per cent, of pure carbide, and which gives 5 cu. ft. of gas 

 per pound ; or, for a ton of carbide, 10,000 cu. ft. acetylene, 

 .two-thirds saturated with moisture, and measured at 60° 

 Pahr. and 30 inches l^arometer. Summer and winter 

 variations of temperature, together with barometric vari- 

 .ations, would cause a difference of more than 15 per cent, 

 in the uncorrected measure of the gas, and gas measured 

 in a mountainous region, without correction for the low 

 barometer, would differ far more from the standard 

 .amount. 



If the acetylene industry shall succeed, the cost of the 

 .carbide will have to be adjusted to the price that the con- 

 sumer may be willing to pay for gas, and it is preferable 

 to treat the subject from this side and to show, as far as 

 laboratory experiments with materials at hand will per- 

 mit, what will be the probable value to the consumer of 

 acetylene gas. 



A very simple experiment illustrates in a beautiful way 

 the ease with which acetylene can be made from the car- 

 .bide. Direct a small stream of water on a half-pound 



