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calcite and a few fossils, chiefly fragments of brachiopods. A thin 
section examined with the microscope shows a compact ground mass of 
calcite with enclosed crystals of the same mineral, some obscure fossil 
forms (bryozoa, brachipod shells or crinoids), and some brown lines 
of bituminous matter. 
Judged as a building material the specimen has all the character- 
istics of a durable stone. The dark-grey color will probably bleach to 
a lighter grey on exposure to the weather." 
(Signed.) A. P. Coleman, Ph. I)., 
Prof. Metall. and Assaying. 
School of Practical Science, Toronto, March 27th, 1893. 
4. Crushing strength per square inch determined by Prof. H. T. Bovey, 
M. A., LL.D., of the Physical Laboratories, McGill College. 
The following is an extract from a letter by Prof. Henry T. Bovey 
on two specimens of limestone from the Rockland quarries : 
Specimen A. Dimensions 2" x 2.02" x 2.01". 
Tested on bed. 
Total crushing strength 92,000 lbs. 
Crushing strength per square inch 22,772 " 
Specimen B. Dimensions 2.01" x 2.025" x 2.01". 
Tested on edge. 
Total crushing strength 60,000 lbs. 
Crushing strength per square inch 14.741 " 
Weight of stone as per sample A= 168. n pounds per cubic foot. 
(Signed.) Henry T. Bovey. 
McGill College, Montreal, March 22nd, 1893. 
It will thus appear from the combined results of the tests made 
both at the Toronto and Montreal laboratories, that the stone from the 
Rockland quarries is of a superior quality. When compared with the 
results obtained from similar severe tests of limestones of Canada and 
the United States these of the Rockland limestone stand high. For 
the record of such tests, the reports published by the State Surveys of 
New York, Pennsylvania and Minnesota besides many other valuable 
contributions contain the most extensive and comprehensive remarks. 
