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Scientific American Supplement, No. 648, June 2, 1888

Scientific American Supple…

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内容简介

For a quarter of a century maritime nations have been continuously engaged in improving the mechanical appliances of their large ports. The use of tracks to bring goods to be placed on vessels as near as possible to the shipping point, the substitution of oblique moles for perpendicular ones in large docks, the creation of a hydraulic method of loading and unloading through movable cranes (which will perhaps in a near future cede to an electrical one), constitute the means most used for expediting transshipments and reducing the expense of them to a minimum. But, at the same time that the facilities for all kinds for handling packages have been increased, it has also become necessary to greatly increase the power of the machines applied to them. The construction of large packets now requires the putting in place of boilers of great weight, and the adoption of the huge pieces that compose the artillery of ironclads necessitates the use of force that has been unknown up to recent times.
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