INDUSTRIAL PROGRESS DURING THE YEAR 1873. Hii 



for whicli extensive Avorks for the extraction of the metal 

 by a humid process are now being erected. The deposits 

 throughout this region may be made to furnish large sup- 

 pUes both of copper and of sulphuric acid, which latter can 

 be utilized in the treatment of the phosphate of lime found 

 near Charleston, South Carolina. This material is there in- 

 terstratified down to considerable depths with the marls of 

 the region, and apparently in vast and almost inexhaustible 

 quantities. Its value for the manufacture of fertilizers is now 

 well known, and it is shipped in great quantities both to 

 the Northern States and to England ; besides which a large 

 amount is manufactured into superphosphate at Charleston 

 for the home market. The evidence accumulated goes to 

 show that this massive and impure phosphate of lime, to 

 which the name of eoprolite, or manure-stone, may still be 

 given, is not of excrementitious origin, though fossil excre- 

 ments certainly occur in many rocks, but has been deposited 

 from solution by a process of concretion which, though little 

 understood, is perhaps analogous to that by which flints are 

 formed. This view is advocated by Sollas, from his study of 

 the eoprolites from the greensand in England, which, accord- 

 ing to him, result from the petrifaction of sj^onges by dis- 

 solved phosphatic matter. The relation between these an- 

 cient deposits and the guano of the Chincha Islands is closer 

 than might be at first suspected, since the latter, according 

 to Edwards, is not excrementitious, as commonly supposed, 

 but rather a stratified deposit of phosphatized sponges and 

 other low oro-anized forms. 



The subject of descriptive Mineralogy has, of course, re- 

 ceived much attention on the part of mineralogists and chem- 

 ists throughout the world ; and the new species discovered, 

 Avith new localities for those already known, are quite nu- 

 merous. For full details relating to this department of 

 science, i-eference must be made to the journals specially or 

 incidentally devoted to the subject; although some indica- 

 tions in reference to American mineralogy may not here be 

 amiss. Two new species have been published by Mr. Gold- 

 schmidt : the first, Trautvnnite, a combination of chromic 

 oxide, ferrous oxide, and magnesia, and Stibloferrite, both 

 from California. 



Mr, Durant, in the Proceedings of the California Academy 



