88 NEW YORK STATE MUSEUM 



The mills, all of which are run in connection with the mines, 

 number seven or eight in all. They have a combined capacity of 

 about 100,000 tons of pre])are(l talc a year. With one or two ex- 

 ceptions they are situated along the Oswegatchie river in the 

 stretch between Edwards and CJouverneur, the sites being selected 

 with reference to water power facilities. 



The reduction of the talc is accomplished in several stages. The 

 lump talc, as mined, is first broken in a jaw crusher of the Blake 

 type. The broken product is then run through a cone grinder or 

 through rolls where it is reduced to i inch size or less. In the 

 third stage the crushed product may be ground between burstones 

 of special manufacture or in a centrifugal grinder of which the 

 Griffin mill is the common type. After this grinding the finest 

 material may be removed by screening or by fans which blow it 

 into settling chambers and forms one of the grades for the market. 

 The remainder undergoes a final reduction in pebble mills. Alsing 

 cylinders are generally employed for the last stage. They are 8 

 or 10 feet long and 6 feet in diameter and are lined with porcelain 

 brick. They make from 20 to 25 revolutions a minute. Their 

 charge consists of about i ton of talc and 3 tons of flint pebbles. 

 The grinding of a single charge takes from 2 to 5 hours depending 

 upon the grade of product that is desired. The fibrous character 

 of the talc is maintained throughout the grinding to the end 

 product so that it is difficult to size the ground talc by screening; 

 consequently the grades of fiber are generally regulated by the 

 duration of the final grinding process. 



The foliated talc undergoes essentially the same treatment. The 

 coarser grades as finished have a scaly appearance much like 

 ground mica and can be used as a substitute in some of its appli- 

 cations. This variety is ground also to an impalpable powder and 

 employed for the same purposes as massive talc. The milling of 

 either variety represents the greater part of the expense of produc- 

 tion of the talc for the market. 



The finished product is shipped in sacks holding 50 pounds each. 

 Quotations are made from Gouverncur as shipping point, though 

 the mills along the Oswegatchie river are near the line of the Gou- 

 verneur & Oswegatchie railroad and their output is loaded directly 

 into cars. The product of the mills off the line of this railroad is 

 hauled by teams to Gouverneur. 



Uses. The talc from this district, as already stated, is mainly 

 used in the paper trade. The fibrous product goes into book and 



