A HISTORY OF THE SODA MANUFACTURE. 253 



which again shows that freedom from restrictions is necessary for the 

 existence of a successful trade. In that year a French house, Messrs. 

 Taix and Co. of Marseilles, persuaded the King of Sicily that his mis- 

 erable revenue would be improved if he granted to them a monopoly of 

 the export of sulphur. The first consequence of this was an advance in 

 the price to 14Z. per ton, from the previous rate of 51. This insane 

 measure produced its own proper remedy. It was soon found that in our 

 Cornish mines, and more particularly in those of Wicklow, in Ireland, 

 we possessed an inexhaustible supply of sulphur in the form of pyrites, 

 and our practical chemists speedily devised the means to avail them- 

 selves of this source for the manufacture of sulphuric acid. In this 

 manner the feeble-minded king bestowed, although unintentionally, a 

 great boon upon this country, as we were relieved from his monopoly, 

 and a large amount of money was beneficially circulated in Ireland. 



In working with pyrites, it was found that a great portion of this 

 mineral contained sulphide of copper, as well as of iron ; and, at an 

 early period I commenced to extract the copper from the burned resi- 

 duum by smelting. I was then engaged in the soda manufacture, in 

 Worcestershire. The ordinary pyrites contained only one per cent, of 

 copper, and this being deemed so small a proportion as to be worthless, 

 the residua were thrown away, and accumulated in large heaps in this 

 country, and on the banks of the Tyne. In 1850 I purchased some of 

 these large accumulations of so-called rubbish, and erected works at 

 Widnes for the extraction of copper and silver therefrom. This led to 

 my smelting upwards of fifty thousand tons of this rejected material, 

 affording employment to nearly one hundred workmen. The practi- 

 cability of such an operation having been thus demonstrated, other 

 manufacturers adopted the same proceeding. Subsequently to the time 

 I have referred to, large importations of copper pyrites for the use of 

 the soda trade have been made from Spain, from which also copper is 

 extracted by smelting. 



In giving directions for the decomposition of sulphate of soda, Le 

 Blanc recommends the following proportions of materials to be used : — 



1,000 parts of sulphate of soda. 

 1,000 „ of chalk. 

 550 „ of carbon. 



These proportions are in the ratio of about three equivalents of 

 chalk to two equivalents of sulphate of soda. They are the same 

 which are now generally employed by the soda manufacturers of the 

 present day, except that about 750 parts of small bituminous coal are 

 substituted for the 550 parts of carbon. 



The mixture is fluxed in reverberatory furnaces, producing black 

 ash containing carbonate of soda and sulphide of calcium, and, accord- 

 ing to the skilfulness of the workman in conducting this operation, there 



