20 JOURNAL AND PROCEEDINGS. 



much larger, being about three feet long and twelve by eight inches 

 in cross section. An alternating current is delivered by means of 

 transformers to the carbons at about loo volts and looo amperes. 

 A small portion of the mixture is fed into the furnace, the upper 

 carbon is raised about three inches, to form an arc, and the mixture 

 is fused by the intense heat, which ranges from 3,500 to 4,000 degrees 

 C, while that of the ordinary smelting furnace is only 1,200 to 1,500 

 degrees C. The carbon is gradually raised and fresh mixture fed in 

 till a mass of molten carbide about three feet high is made, when 

 the current is turned off and the carbide allowed to cool. The noise 

 of the arc is said to be very peculiar, especially when the supply of 

 mixture begins to fail. 



COST OF CALCIUM CARBIDE. 



To positively ascertain the cost of this product the " Progres- 

 sive Age" of New York sent three commissioners to Mr. Willson's 

 AUuminum factory at Spray, N. C, in March last, to investigate 

 thoroughly, and their report is published in that journal under date 

 of i6th April, 1896. The commission consisted of Messrs. Hous- 

 ton and Kennelly, well-known electricians, and Dr. Leonard P. Kinni- 

 cutt, director of the department of chemistry at Worcester Polytech- 

 nic Institute, who investigated thoroughly and took full charge of 

 the factory during two separate days, making two runs of the sub- 

 stance and taking samples with them for testing in their own labora- 

 tories. Notwithstanding that the factory at Spray was only an experi- 

 mental one, and the greatest possible output only one ton per 24 

 hours, and the fact that transportation of material was excessive, 

 costing $3.05 per ton for coke and $455 per ton for lime, and esti- 

 mating $11 per day for labor, including a superintendent at $4 per 

 day, they figure the cost at $32.76 per ton. 



Messrs. Houston and Kennelly add a separate estimate for the 

 production of five tons daily under more favorable circumstances, 

 but with water power at $5 per year, as at Spray, and figure the cost 

 at $20.04 per ton. They add: " The cost of producing calcium carb; 

 "electrically, is evidently limited by the cost of limej coke and elec- 

 " trie power, no matter what the scale upon which the process is 

 *' conducted, 



" If we assume a perfect electric furnace in which neither ma 



