Chemical Industries and Resources 

 industries. However, its production on this coast 

 can not be taken as an index of the chemical ac- 

 tivities, as a very large portion is used in the re- 

 fining of petroleum. There are, at the present 

 time, seven different companies with a total daily 

 production equivalent to 400 tons of monohydrate 

 or 100 per cent sulphuric acid. Large capital has 

 been invested in its production and there can be 

 no question as to the possibility of the shortage 

 of this acid. Many large plants are burning pyrites 

 and it is safe to say that from 90 per cent to 95 

 per cent of the acid produced is derived from this 

 source. The pyrites are mined either in Shasta 

 or Alameda County, and in 1913 there was shipped 

 for the manufacturing of acid 79,000 tons. This 

 amount will not account for the estimated pro- 

 duction of acid from this source alone, but it 

 must be borne in mind that both mines and smelters 

 are now shipping pyritic ores and concentrates to 

 be roasted by the acid works and that this source 

 must be taken into consideration. 



During the last few years the public has been 

 paying considerable attention to smelter fumes, 

 and the smelters are endeavoring to turn over all 

 their roasting ores to the acid works which also 

 increases the revenue of the smelter. On the other 

 hand, the acid works are purchasing a cheaper 

 sulphur, but the ores should not have too high 

 values in gold, silver or copper contents, for the 

 cinder or roasted ore must be returned and any 

 loss paid for. The large plants are all operating 

 the contact system and all three, the Schraeder- 

 Grillo, Mannheim and the Badische, have been tried 

 out around the Bay of San Francisco. Two separate 

 Mannheim installations are still operating, and a 

 third corporation has developed the Badische- 

 Herreshof, which is said to be the best of them 

 all. The high explosive works and oil refineries 

 are noAv using almost anhydrous and fuming acids, 

 respectively, and such acids can only be produced 

 by the contact system, which is at present respon- 

 sible for at least 90 per cent of all the sulphuric 

 acid. 



Practically the entire production of nitric acid 

 is taken by the high explosive works, and on the 

 recovery of the spent acid (the mixed acid which 

 has been used for nitration) the nitric acid is 

 recovered as a weak acid or as ammonium nitrate. 

 The nitre cake, which remains in pot or retort after 

 distilling the nitric acid, is thrown away and daily 

 some seventj-five tons are disposed of in this man- 

 ner. The nitre cake is almost a bisulphate of soda, 



238 



