THE NONMETALLIC MINERALS. 251 



sand chrome to be found within the Baltimore region, Isaac Tyson, jr., began to fear 

 that the sources of supply could not much longer be restricted to his ownership. In 

 such an event he realized that he would be compelled to manufacture his ores or to 

 sacrifice them in competition. 



The method of manufacture previously in use was to heat a mixture of chrome ore 

 and potassium nitrate upon the working hearth of a reverberatory furnace. The 

 potash salt yielded oxygen to the chromic oxide present, forming chromic acid, 

 which, in turn, united with the base, producing potash chromate. The process was 

 wasteful and exceedingly costly. Afterwards the process was somewhat cheapened 

 by substitution of potassium carbonate for the more costly nitrate; oxygen was taken 

 from heated air in the furnace. But not until 1845, when Stromeyer introduced his 

 process, was the manufacture of chromic acid placed upon a safe mercantile basis. 

 In this process pulverized chromic iron is mixed with potassium carbonate and 

 freshly slaked lime, and the mixture is heated in a reverberatory furnace. After 

 chromic oxide is set free in the charge it is freely oxidized because of the spongy 

 conditions of the lime-laden charge. 



Among the first steps of Isaac Tyson, jr., was to apply, in 1846, to Yale College 

 for a chemist for his chrome works. In response a young man named W. P. Blake, 

 who was then a student in the chemical laboratory, was sent. For a while Mr. Blake 

 did excellent service in the new factory, but he was not willing to remain. 



Mr. (now Professor) Blake was the first chemist to be employed in technology 

 upon this continent, while the Baltimore works were the first to appreciate the value 

 of chemistry. After the departure of Mr. Blake another chemist was secured from 

 the first laboratory ever instituted for the teaching of chemistry, that founded at 

 Giessen by Liebig. In succession cauie another chemist from the same laboratory, 

 and this gentleman is yet employed in the works. 



Between 1880 and 1890 the American production of chrome ore 

 has varied between 1,500 and 3,000 tons. The total eastern product 

 in 1886 was 100 tons only. Chrome ore was discovered in California 

 in 1873, and since 1886 this State has been the only one to produce 

 this mineral. From 2,000 to 4,000 tons of Turkish chrome ore are 

 now annually imported into the United States, most of which is 

 utilized in Baltimore. 



BIBLIOGKAPHY. 



. Lake Chrome and Mineral Company, of Baltimore County. 



American Mineral Gazette and Geological Magazine, I. April 1, 1864, p. 253. 

 HARRIE WOOD. Chromite and Manganese. Chromic iron and manganese ores have 

 been found in considerable quantities, but the deposits have not yet been exten- 

 sively worked. The chromite occurs in the Bowling Alley Point, Grafton, Young, 

 and Bingera districts. Manganese ores are found widely distributed throughout the 

 Colony; but the principal deposits are at Bendemere, near Moonbi, Glanmire, 

 Rocky, and Broken Hill. 



Mineral Products of New South Wales, Department of Mines, 1887, p. 42. 

 Ueber schwedisches Chromroheisen und Martinchromstahl. 



Berg-und Hiittenmannische Zeitung, XL VII, 1888. p. 267. 

 Die Chromersenerz-Lagerstatten Xeuseeland. 



Berg-und Hiittenmannische Zeitung, XL VII, 1888. p. 375. 

 Chrome Iron. 



Eighth Annual Report of the State Mineralogist of California, 1888, p. 326. 

 Chromite Mined at Cedar Mountain. 



Eighth Annual Report of the State Mineralogist of California, 1888, p. 32. 



