... Report on the building and ornamental stones of Canada, vol. I-V (1912)
Parks, W. A. (William Arthur), 1868-1936, Canada. Mines Branch · Ottawa : Government printing bureau · leaf 260
l coincided with the top of the sandstone. The good stonewas then quarried out to the bottom of the bed throughout the extent of thetunnel. Twenty feet in fr(jm the mouth of the tunnel, drifts were run later-ally from the main tunnel. These were usually made 30 feet wide and thegood stone was… … /aay 156 was taken out as before. In this manner the workings were carried backseveral hundred feet into the mountain. The main tunnels were placed atintervals of about 60 feet in the places where the observations were made,but I am not awaie that any fixed interval was adopted throughout the…
Building stones
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