Cast iron, however, if subjected to only one single fusion, is rarely sufficiently homogeneous; and it requires a second fusion completely to refine it by dispossessing it of its last earthly deposits. So long before being forwarded to Tampa Town, the iron ore, molten in the great furnaces of Coldspring, and brought into contact with coal and silicium heated to a high temperature, was carburized and transformed into cast iron. After this first operation, the metal was sent on to Stones Hill. They had, however, to deal with 136,000,000 pounds of iron, a quantity far too costly to send by railway. The cost of transport would have been double that of material. It appeared preferable to freight vessels at New York, and to load them with the iron in bars. This, however, required not less than sixty- eight vessels of 1,000 tons, a veritable fleet, which, quitting New York on the 3rd of May,on the 10th of the same month ascended the Bay of Espiritu Santo, and discharged their cargoes, without dues, in the port at Tampa Town. Thence the iron was transported by rail to Stones Hill, and about the middle of January this enormous mass of metal was delivered at its destination.
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