620 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. [4] 



Tron. 



A collection of ores of over 500 specimens, selected from the collections 

 made by the Tenth Census, under the direction of Prof. R. Pumpelley,to 

 illustrate the iron industry of the United States, showing all the diflfer- 

 ent kinds and varieties of iron ore found in this country. 



This collection is not intended to show the full occurrence in any one 

 region, but only the prominent varieties of the different regions. 



Manganese. 



Manganese ore from Virginia and Georgia. 



Zinc. 



The New Jersey ores, including Franklinite, Zincite, Willemit^, and 

 Calamine. 

 The silicate and carbonate ores of Tennessee and Virginia. 

 The sulphide ores of Missouri and Kansas. 



Coal. 



A collection showing the different varieties of coal from Pennsyl- 

 vania and Virginia, including anthracite, semi-bituminous, bituminous, 

 splint and cannel coal ; also a large collection illustrating the methods 

 of coal mining, including some large photographs (taken by electric 

 light) of the interior of a coal mine, showing the formation of the coal- 

 seam and its peculiarities, together with the men at work. These are 

 the first photographs ever taken of the interior of a coal mine. 



Sulphur. 



Native sulphur from Nevada- 

 Iron pyrites from Massachusetts and Virginia. 



Besides the above systematic ore collections, some illustrations of ores 

 will be found in the metallurgical collections. 



In making up the metallurgical collection it has not been possible to 

 exhibit the production of each metal exhaustively, owing to the small 

 amount of suitable material previously in the department, and to the 

 short space of time available for making new collections. 



A few systematic illustrations of metallurgical operations are shown. 

 In making these collections it has been designed to treat a few subjects 

 thoroughly rather than a large number superficially. After suitable 

 consideration a few representative works were selected for illustration, 

 and have been worked up as completely as possible. 



Beginning with the ore as mined, each step in its i)reparation for 

 smelting is shown, together with the hy or waste products of such 

 treatment. To illustrate the smelting operation the ores, the fuels, the 

 fluxes, and every other material entering into the operation are shown. 

 Following through the process, each product of each operation up to 

 the final product of the works is represented j to these are added, where 



