The building and ornamental stones of North Carolina (1906)
Watson, Thomas L. (Thomas Leonard), 1871-1924, Laney, Francis Baker, 1875-1938, Merrill, George P. (George Perkins), 1854-1929 · Raleigh, [N.C.] : E.M. Uzzell, Public Printer · leaf 232
t thesubstitution of water under pressure for powder after the cleavage hasextended some little distance from the drill hole was an improvement,they were not satisfied and experimented with compressed air, with theresult that they found that compressed air was as much of an improve-ment over water… … THE VARIETIES OF BUILDIXG STONES. 159 In the center of the sheet or area to be lifted a drill hole 2 to 3inches in diameter is sunk 6 to 8 feet in depth, depending on thegreatest thickness of stone required, and the operation is continued bythe discharge of successive small amounts of powder…
Building stones · Quarries and quarrying
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
