San Francisco : Architect and Engineer, Inc · leaf 379
otan hour. The columns are six feet, twoinches in height and four feet, twoinches in diameter. Before cutting then-weight was twelve and a half tons, andafter cutting they weighed four andthree-quarter tons. Each section of thecolumns are cut with a large Patchgranite lathe so that the columns… … BORING AND CORING MILL. COLUMNS ARE CUT IN THIS ROOM BY HUGE MACHINESWHICH CUT AT THE AVERAGE SPEED OF ONE FOOT AN HOUR and in no other industry, perhaps, is theexemplification of the mechanical ageshown in a greater measure than in theproduction of granite. When a granite block is taken fromthe…
Architecture · Building
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
