THE MINING AND QUARRY INDUSTRY I912 85 



the writer's visit. It is an opening 125 feet long and 80 feet wide 

 and 20 to 30 feet deep. The marble here is of medium color, mottled 

 or veined on top, but becomes dark blue in depth which is the grade 

 particularly sought, as the other quarries supply lighter stock of 

 good quality. The bedding structure dips northwest 30 and pitches 

 southwest 25 °. Two vertical systems of joints intersect the beds, 

 the one running N. 30 W. and the other N. 65 ° E. A trap dike 

 from 2 to 3 feet wide crosses the quarry in the latter direction 

 which is nearly that of the strike; it dips south at a high angle. 

 The dike shows a serpentinous groundmass, with lath-shaped feld- 

 spars, and is probably a diabase that has been considerably 

 weathered. 



The two St Lawrence quarries near the mill are vertical rock cuts 

 with a surface of about 20,000 square feet each and a depth in 

 the northerly quarry of 80 feet and of 40 feet in the southerly one. 

 They have supplied large quantities of building marble of which 

 examples are seen in Gouverneur, Watertown, Ogdensburg, Roch- 

 ester and other places. The monumental stone is mainly the selected 

 darker quality which is sold under the trade name of " St Law- 

 rence " but includes some lighter stone called " Adirondack." Near 

 these quarries, a drill hole was put down which penetrated the vein 

 for 400 feet. The dip is here about 20 . 



The quarries are well equipped with six channelling machines, two 

 gadders, and three large derricks. The mill is the largest in the dis- 

 trict, having sixteen gangs of saws, besides rubbing beds, lathes, and 

 polishing machines. The mill is run by electricity derived from the 

 Hailesboro water power station. 



Northern New York Marble Co. The property of the Northern 

 New York Marble Co. lies in the southwestern section of the belt, 

 separated from the other quarries by a long stretch of undeveloped 

 ground. It appears to be considerably south of the course of the 

 principal marble beds, but is possibly a continuation of the vein de- 

 veloped in the extra dark quarry of the St Lawrence Company. 

 This is segregated by the similarity in the product, as well as by 

 the relative position of the two quarries. The structural features, 

 however, are not uniform, as the strike becomes almost east-west 

 and the dip is very high — about 8o° N. at the more westerly prop- 

 erty. There is the same westerly pitch of the beds. 



The principal quarry opening is about 140 feet long and 75 feet 

 wide and has been worked down to 210 feet depth. This has been 

 abandoned on account of the depth. A second quarry 100 feet south 



