PRELIMINARY HANDBOOK OF THE DEPARTMENT OF GEOLOGY. 49 



bestus is shown by 40 specimens.* Sixty specimens show character- 

 istic forms of the various phosphates and other mineral substances 

 used in the manufacture of fertilizers. 



Fictile materials are illustrated by some 60 specimens, including all 

 the usual varieties of clay and kaolin. 



The native compounds in which carbon forms the chief constituent 

 are shown in a series of some 500 specimens, which begins with pare 

 carbon in the form of diamond and graphite, and follows through coals 

 bitumen, and petroleum, ending with natural gas. 



In this series the most important collections are those of anthracite 

 coal from the Kohinoor colliery of the Philadelphia and Reading Coal 

 and Iron Company, and the very extensive collection of petroleum, 

 which includes varieties from all the principal localities of the United 

 States, with a very complete illustration of its technology. A few for- 

 eign localities are also represented. 



Maps showing the geographic distribution of the ores of iron and 

 mercury, of coal, salt, petroleum, and bituminous matter accompany 

 this series. It is hoped to add to these others showing the distribution 

 of the precious metals as well. A table in each of the exhibition halls 

 is supplied with books descriptive of the collections. 



The following show the form of label used in this series: 



Petroleum and its Derivation Products. 



pRUDE PETROLEUM.— Dark greenish- 

 ^-^ red ; specific gravity on sample collected 

 June, 1885, 472 Bau*ne. 



Well No. 12, Lot 3,194, Howe, Forest County, Pennsylvania. 



59,789- 

 Collected by S. F. Peckham. 



From well in third Sandstone of the Petroleum Measures ; 

 sand here 15 feet in thickness. Oil in sand; depth of well 

 1,655 feet; drilled 1883; torpedoed. Yielded 1,950 barrels of 

 oil on first day of flow. 



The Application of Graphite. 



/GRAPHITE. — For making pencils; contains 

 ^* from 5.143 to 17.682 per cent, of ash. 



Dominion of Canada Plumbago Company, Buckingham, Prov- 

 ince of Quebec, Canada. 51,612. 



American Institute Mining Engineers 1885. 



* Mainly the gift of Hie II W. Johns Company, of New York. 



