very comprehensive idea of the general appearance of the appliance. Two truck tender. There are a great many points of ex- cellence in the design of this engine for the service shafts each 25 feet 6 inches in diameter are at present being bored by this machine at a colliery at Mansfield, in which… … air drill, pre- rying the fire- A NEW SYSTEM OF SINKING SHAFTS. ferably two box out later- AMERICAN the ingenious freezing process for boring ally over the rear pair of drivers. Its dimensions are: on each arm. This plant is put together complete on shafts through sandy soil. We illustrate herewith…
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