THE MINING AND QUARRY INDUSTRY IQI2 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 4o feet in the southerly one. 
They have supplied large quantities of building marble of which 
examples are seen in Gouverneur, Watertown, Ogdensburg, Roch- 
ester aiid 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 hére 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 80° N. at the more westerly prop- 
_erty. There is the same westerly pitch of the beds. 
The principal quarry opening is about r4o 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 
