e, Md. pearance it burst into three or four fragments, which platform. became of different colors, those in the rear being a 0 This invention has been patented by Mr. Adam H. IMPROVED CAISSON. vivid green, changing to purple, while the foremost Bell, of Hillsborough, Ill. The object of the… … by momentarily raising the temperature to a particu- lar degree, can also be acquired by subjecting the steel for alonger time to a much lower temperature. For borough, IIl.,—is to facilitate the work of sinking coal example, the temper which the annealing color—yellow shafts and wells and…
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