522 



METALLURGY. 



with meshes of one third of an inch, are shov- 

 eled on the heap and constantly added, so as 

 to keep the temperature of the outside nearly 

 endurable to the hand. In about ten days, no 

 part of the heap having been allowed to fuse, 

 no more attention will be needed ; and in 

 about eleven weeks the mass will be ready to 

 remove to the furnace. If the operation has 

 been successfully performed, out of 350 short 

 tons of ore put in the heap, not more than 

 twenty tons will require any further roasting. 

 At the Ely mine, Vershire, Vt., and the Eliz- 

 abeth mine, Strafford, Vt., the entire heaps 

 are smelted, and none of the ore requires re- 

 roasting. 



The Doetsch process for the extraction of 

 copper has been tested on a large scale by the 

 Rio Tinto company for several years. Its es- 

 sential features are as follow : The raw ore, 

 broken to a uniform size of about 0*4 of an inch, 

 is piled in heaps from ten to thirteen feet high, 

 in which channels are left along the bottom 

 and vertical draught-holes are provided for. 

 About two per cent, of salt is scattered over the 

 top of the pile, which is about 45 feet wide. A 

 basin for the leaching fluid, about thirty feet 

 square, is formed on the top of the pile, into 

 which the solution obtained after the precipita- 

 tion of the copper, subsequently saturated with 

 chlorine, is allowed to flow. Trickling through 

 the ore, the solution acts upon the copper, and 

 is gathered in gutters, conducted to tanks, and 

 made to flow through long sluices, where the 

 copper is precipitated with metallic iron. The 

 precipitate is dried on hot iron plates, and the 

 solution, after precipitation, is dropped through 

 a coke-tower, where it is met by an ascending 

 current of a mixture of chlorine and hydrochlo- 

 ric acid. 



Experiments begun at Vede"nes in 1880 for 

 applying the Bessemer process to the reduc- 

 tion of copper were unsuccessful as long as 

 the ordinary Bessemer converter, with its 

 vertical tuyeres, was used, on account of the 

 premature cooling of the copper before the 

 iron and sulphur were entirely eliminated. 

 Horizontal tuyeres having been substituted for 

 vertical ones, so that the blast was forced into 

 the bath at a point above the bottom of the 

 converter, the results were at once improved, 

 and it was found very easy to convert copper 

 matte rapidly into blister-copper containing 

 only from one to one and a half per cent, of 

 foreign substances. The process has been car- 

 ried out on a working scale in the old Royal 

 foundry at Eguilles, near Sorgues. The op- 

 eration does not differ essentially from that 

 in the Bessemer steel converter. When the 

 matte treated is very poor, casting must be 

 proceeded with at once, otherwise a violent 

 reaction is liable to take place, but with rich 

 mattes it goes on without any difficulty. Arse- 

 -nic and antimony are eliminated; cobalt is 

 partly scorified and partly remains with the 

 copper; and nickel and bismuth are both con- 

 centrated in the product. The copper obtained 



has a very constant composition, varying as 

 follows: Copper, from 98-05 to 98-08 ; sulphur, 

 from -09 to -08 ; and iron, from -06 to -04. 



Nickel. Mr. William P. Blake, in a paper 

 read before the American Institute of Mining 

 Engineers at Boston, recounts some of the ad- 

 vances in the metallurgy of nickel that have 

 been made in this country. For some time 

 after its discovery by Oroustedt in 1751, nickel 

 received no applications, and remained com- 

 paratively unknown. Inasmuch as nickel first 

 became known in the industrial arts in an al- 

 loy, there were no special attempts to produce 

 the metal in a state of extreme purity. The 

 nickel silver of commerce answered all the ex- 

 isting demands, and was of course much easier 

 to make, and cheaper than the pure nickel. 

 It found a large use as a substitute for silver- 

 ware, especially when the new art of electro- 

 plating was developed, and is to this day the 

 most desirable alloy for plating. The use of 

 nickel alloy for small or subsidiary coins next 

 made an increased demand for nickel. Tenta- 

 tive efforts were made by Dr. Feuchtwanger, 

 in New York, in the year 1837, and he actually 

 issued many small one-cent and three-cent 

 pieces, made of a nickel alloy. Switzerland 

 commenced using nickel-alloy coins in 1850 ; 

 the United States in 1857, though sample coins, 

 one-cent pieces, had been made by Prof. James 

 0. Booth at Philadelphia in 1853. Nickel-ore 

 is more generally distributed throughout the 

 mineral-bearing portions of the United States 

 than is generally supposed. It is commonly 

 associated with chrome-ores from Canada to 

 Maryland, and equally with the chrome-ores 

 of the Pacific slope. The chief supply of nickel 

 for the United States has been obtained from 

 Lancaster Gap, Pa. This locality was worked 

 some thirty years ago by Prof. James C. Booth 

 and others. About ten years later Mr. Joseph 

 Wharton purchased the works, and established 

 the industry at Camden, N". J., where it has 

 since been carried for ward. But Mr. Wharton, 

 not being content with the production of im- 

 pure nickel, early commenced experimenting 

 to determine whether nickel could not be pro- 

 duced in a pure and malleable condition, sus- 

 ceptible of being worked in nearly the same 

 manner as iron. In 1873 Mr. Wharton sent to 

 the Vienna Exhibition a sample of nickel in 

 the form of axles and axle-bearings, and at the 

 exhibition in Philadelphia in 1876 he exhibited 

 a remarkable series of objects made of wrought 

 nickel. The judges reported the exhibit to the 

 commission as worthy of an award in the 

 following terms : " A fine collection of nickel 

 ores from Lancaster county, Pa., with nickel- 

 matte, metallic nickel in grains and cubes, and 

 manufactured nickel, both cast and wrought; 

 nickel magnets and magnetic needles, cast co- 

 balt, electro-plating with nickel and cobalt, 

 and salts and oxides of both these metals ; the 

 whole showing a remarkable degree of prog- 

 ress in their metallurgical treatment." 



Dr. Fleitmann, of Iserlohn, Westphalia, has 



