KEFOKT or UKfAKTMENT OF METALLURGY. 241 



iug- of auriferous autl argentiferous copper ores from the Colorado 

 Smelter. 



The followiug collections were obtained, upon solicitation of the cu- 

 rator, for the is"ew Orleans Exposition : 



A collection representing the extraction of gold from the auriferous 

 gravel of California by the hydraulic process. Collected by Mr. W. H. 

 IJadford. 



A collection representing the extraction of gold from auriferous pyrite 

 from the Bobtail Mill, Black Hawk, Colo. Collected by E. M. Eogers. 



A collection representing the delicate manipulation required in the 

 manufacture of gold leaf. Presented by Uastings »S: Co.. of Philadelphia, 

 Pa. 



A very large and extensive collection of the ores of Utah. Presented 

 in exchange by Prof. J. E. Clayton, Salt Lake City, Utah. This col- 

 lection is especially- valuable :is tilling in many gaps of our permanent 

 collections, and also supi)lying some ores which are only found in Utah. 



Collections representing some of the recently discovered tin ores of 

 the country. From Virginia, i)resented by the Cash iVIining Company; 

 from Alabama, presented by Dr. George W. Gessner ; and from Dakota, 

 presented by Prof. George W. Maynard. 



A collection representing the process of manufacture of white lead 

 and other lead paints. Presented by Harrison Brothers & Co., of Phil- 

 adelphia, Pa. 



A very large and interesting collection representing the manufacture 

 of copper into various commercial forms, the manufacture and utiliza- 

 tion of brass, and the process of wiredrawing. Presented by the Au- 

 sonia Brass and Copi)er ^Yorks, Ansouia, Conn. 



A collection representing the smelting and refining of copper from 

 various sulphureted ores. Presented by Pope, Cole & Co., Baltimore, 

 Md. 



A collection representing the refining of native copper separated from 

 the ores of the Mass Mine, Lake Superior. Presented by C. G. Hussey 

 cV Co., Pittsburgh, Pa. 



A collection representing the smelting of pig-iron from fossiliferous 

 ores at Itockwood, Tenn. Presented by the Roane Iron Company, Chat- 

 tanooga, Teun. 



A collection representing the smelting of pig-iron from brown ores 

 in Virginia. Presented by the Longdale Iron Company, Longdale, Va. 



A collection representing the very interesting and intricate process of 

 the manufacture of crucible steel. Presented by Miller, Metcalf & 

 Parkin, Pittsburgh, Pa. 



A very interesting collection representing various processes of iron 

 :iMd steel manufacture in Sweden, together with descriptions of the proc- 

 Ls.ses. Presented by X. Lilienberg, New York. 



A large collection of the zinc ores from the Bertha mine. Presented 

 by Thomas Jones, Pulaski, Va. 

 S. Mis. 33, i)t. 2 10 



