208 



Corsica, and owing to the difficulty with which it was obtained and its 

 exceptionally fine quality commanded a very high price in the market, 

 reaching as much as $250 to $300 per ton ; but the discovery of the 

 chrysotile deposits in the province of Quebec, of a quality equally 

 well adapted for spinning as that of Italy, taken in connection with the 

 fact that these were situated directly along a line of railway within 

 short haulage of a shipping port, almost immediately revolutionized the 

 industry, and has lately nearly closed the Italian mines. 



Much of the so-called asbestus of these mines, however, is not 

 adapted for spinning, and is used for the manufacture of mill-board, 

 cements, paints, etc., as is also the output from such mines in the 

 United States as have been working more or less constantly for the last 

 twenty years. The output of the Quebec mines has even alreadv had 

 such an effect upon these that their present output is probably scarcely 

 a tenth of what it reached ten years ago. 



In Ontario, also, a large quantity of the variety known as actino- 

 lite is mined and ground at Bridgewater in Hastings county. This is 

 used for cement roofing being mixed for that purpose with tar r the 

 fibrous texture of the material being sufficient to allow of its felting 

 sufficiently, but not for spinning. 



The non conducting substances available in the process of manufac- 

 ture in addition to asbestus are not numerous. Among tbe most im- 

 portant probably may be mentioned infusorial earth, which is generally 

 found as a white or grayish white earthy material occupying the beds 

 of certain lakes, or under peat bogs and in deposits frequently of very 

 large extent. In composition this earth is almost a pure silica and is- 

 composed of the siliceous shells or crusts of diatomaceous plants, spicules 

 of sponges, &c. It is also known as tripolite and under the name of 

 Tripoli, or polishing powder, is familiar to most housekeepers. The 

 localities where infusorial earth occurs most abundantly in the States 

 are in Virginia, where an immense bed, many feet thick, underlies the 

 city of Richmond ; and in California, where a deposit of fifty feet in 

 depth occurs near Monterey. In Germany large deposits also are 

 known under the name kieoelguhr, and much of this material used in the 

 United States comes from that country. Numerous lake bottoms filled 

 with this substance occur in the provinces of Nova Scotia and. New 



