DESIGN OF A WIND HAMMER FOR BORING ROCKS

摘要

I have long entertained a project for more expeditiously boring shot holes, especially in driving deep levels, by concentrating the power and operations of a number of men (say four or six) employed at a remote and well-aired part of the mine, in condensing air by an air pump, similar to that used for airing a diving bell.The condensed air conveyed by a small iron (gas) pipe to within a proper distance at the end of the drift, from whence conveyed by an elastic pipe to a small cylinder of 3 or 4 inches diameter, whose piston should be a hammer of about twelve pounds weight, which, moved at the rate of 200 blows per minute, and applied to an ordinary borer, held and