Page:Popular Science Monthly Volume 81.djvu/185

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Much the same process is carried out at the Bermudez deposit, but the asphalt is carried from the lake to the shore of the river on a railway instead of by cableway. In either case, the crude material having been dumped into the hold of the vessel, runs together into a compact mass during the voyage to the United States. In consequence, it must be again picked out by laborers as it lies alongside the pier, and loaded into skips in which it is raised and again dumped into others, which are carried by a small railway to large storage bins holding several thousand tons, where it is again hoisted and dumped for storage until it is refined. Of course, in these bins it again runs together into a solid mass. As a supply is needed for refining, it is picked out and transferred to large rectangular tanks holding a hundred tons each, which are provided with gangs of pipe carrying steam at a pressure of 125 pounds and of about 325° F. This heat removes the water and melts the pitch.