The Phosphates of America. 101 



measured during the course of each experiment, was found to 

 represent from two, to two and a half per cent, of the whole prod- 

 uct, the entire gain being thus brought up to the extraordinary 

 total of about eighteen per cent. Mr. Scheurer-Kestner is proba- 

 bly one of the best manufacturing chemists in the world, and as a 

 shrewd man of business, he supplements his theory by a very solid 

 and practical final piece of evidence. 



Using his own words, he says that before the Glover tower was 

 erected in his works at Thann, his sets of chambers produced in 

 each twenty-four hours six tons of oil of vitriol on the basis of 66 

 Beaume. Ever since the tower has been adopted and brought to 

 proper working order, the production has been increased to 7.280 

 tons. The difference, 7.280 6.000 = 1.280, in actual practical 

 working, therefore, represents seventeen and a half per cent, of his 

 total output. 



Mr. Scheurer-Kestner attributes the formation of this sulphuric 

 acid, outside the leaden chamber, to a double origin, about one-half 

 being due to the anhydride produced during the combustion and 

 dissolved by the descending current of liquid in the tower, and the 

 other half being spontaneously formed by the action of the nitrous 

 compounds on the ascending sulphurous acid. 



COSTS OF PRODUCTION. 



From what has preceded it is perfectly clear that the actual 

 cost of sulphuric acid entirely depends upon three chief conditions: 



First. The price of sulphur. 



Second. The resources, adaptability and excellence of the 

 working plant. 



Third. The chemical, mechanical and, generally, industrial 

 skill of the working management. 



It would, therefore, be obviously unfair to make any allowance 

 for short-comings which have no right to exist, and it will be wise, 

 in going into figures, to assume perfection in every detail. 



A correct basis for calculation is furnished by what is com- 

 monly known as chamber acid that is to say, the product daily 

 formed in the chambers and subjected to no other concentration 

 than that by the Glover tower. With proper care it may be made 

 to average a gravity of say 52 Beaume, and for the decomposi- 

 tion of average natural phosphates no greater strength than this is 

 required. 



