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THE POPULAR SCIENCE MONTHLY.
The advantage of using powder and dynamite combined is thus explained. If dynamite alone were used, the breakage would be carried
American Dredge (Reduced from cut in "Scientific American").
too far; the fragments could not be as conveniently loaded by cranes. The effect of powder would be to project the fragments too far, thus damaging, it might be, the neighboring works. As regards the use of
