218 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1907. 
while in the Wohlwill process a solution of gold chloride is utilized. 
In America the Philadelphia and Denver mints are equipped with 
electrolytic parting apparatus, and a similar installation of electro- 
lytic baths is now being erected at the Government mint in San 
Francisco. Many of the American copper refineries also have an 
electrolytic plant for refining the silver obtained as a by-product in 
the copper-refining process. In Europe electrolytic refining is carried 
on at Frankfort by the Deutsche Gold- und Silber-Scheide Anstalt 
and by the Norddeutsche Affinerie at Hamburg, details of the Wohl- 
will gold-refining process having been worked out at the latter refin- 
ery. Electrolytic bullion refining is also carried out in Great Britain 
and in France, but no details of the works are available for publica- 
tion. A recent improvement of the Moebius process is the use of 
gelatine, which gives a smooth coherent, in place of a rough crystal- 
line deposit at the cathode. 
Calcium carbide and acetylene—Calcium carbide is obtained by 
heating lime and coke in an electric furnace, and it was first produced 
in a large scale by Willson at Spray in the United States in the year 
1893. The late Henri Moissan about the same time produced this 
compound in his laboratory in Paris, and the European patents 
granted to Willson have not been upheld, owing to the earlier publi- 
cation of the results of Moissan’s chemical researches upon the electric 
furnace and its products in the “ Comptes Rendus ” of 1894. 
The early history of the calcium carbide and acetylene industries 
is chiefly a record of reckless finance, worthless patents having been 
used for company flotations upon a large scale, with serious results 
for the investors and for the industry. The period culminated in 
1899-1900 with a series of failures and financial “ reconstructions.” 
Since that year the companies have been slowly recovering from the 
effects of this unwise boom. Though acetylene gas has not displaced 
other illuminants to the extent that was at one time expected, it is 
now used for various purposes much more widely than is generally 
recognized, and central acetylene-generating stations are found in 
very many small village communities in Europe and America. 
According to the most recent estimates there are now between sixty 
and seventy works engaged in the production of calcium carbide, and 
the aggregate production amounts to between 90,000 and. 100,000 tons 
per annum, valued at £1,000,000. The United States, Italy, and 
France head the list of producing countries, and are also the largest 
consumers of carbide for acetylene-generation purposes. During the 
period of inflated finance several works for the manufacture of carbide 
were started in the United Kingdom. All of these have ceased oper- 
ating, and only one small works is now active, at Askeaton in Ireland. 
The greater portion of the carbide consumed in the United Kingdom 
is therefore imported from Norway and from other countries which 
