QUARRIES IN HANCOCK COUNTY. 
103 
nesia) extractable with dilute acetic acid. To allot all the C0 2 to 
the CaO would give 0.10 per cent of lime carbonate in the granite. 
The quarry, opened about 1880, measures about TOO by 3.00 feet, 
and from 20 to 75 feet in depth, averaging about 35 feet. (See PL 
II, A.) The drainage from its upper half flows seaward, but that 
from its lower half must be pumped after heavy rains. Water for 
steam purposes was brought in a " water boat' 1 a mile from Stoning- 
ton at an expense of $110 per month, but a well that was being bored 
in the granite near the shore was expected to yield a supply sufficient 
to save this large expenditure. Little or no stripping has been 
required. 
Rock structure: The sheets vary in thickness downward, and dip 
from 20° to 25° SE. Joint courses are shown in fig. 10. A dips 80° 
Pig. 16. — Structure at Ryan-Parker quarry. Crotch Island. 
and forms a heading on the north, and B also forms one. Both A 
and B are infrequent. The rift is vertical and trends N. G0° W. 
Sap occurs from G to 12 inches on either side of joint B. 
The plant consists of 9 derricks, worked by 9 hoisting engines; a 
traveling crane of 20 tons' capacity ; one compressor of 900 cubic 
feet capacity per minute; 8 large pneumatic drills; a number of 
pneumatic plug drills; 4 surfacers; one lathe carrying stones 8 feet 
by 2 feet 6 inches; and two steam pumps. 
Transportation to the wharfs is effected by means of gravity on 
tracks 75 and 100 feet long. 
The product is used chiefly for massive construction and for build- 
ings, and its market is New York, where the firm is engaged in 
building enterprises. Among the public structures made of this 
granite are the piers of the Blackwells Island bridge in New York. 
In 1905 this quarry was furnishing the stone for the retaining wall 
of the Riverside Drive in New York. 
