《Scientific American Supplement, No. 601, July 9, 1887》Various电子书txt下载、在线阅读、内容简介、评论读后感-当当读书

Scientific American Supple…

Various

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The gunboat Eber is an improved vessel of the Wolf type, but differs from other vessels of its class in that it has not a complete iron hull, only the frame and deck beams being of iron, while the planking is of wood and yellow metal. No copper is used on the bottom. The "composite system" of building is looked upon with favor for ships of this kind, because iron vessels which are kept permanently at stations in the tropics soon become overgrown in spite of good care, and thus suffer a great loss of speed. In a wooden vessel the crew's quarters are better and more healthful than in iron vessels, for they are not as much affected by the temperature outside of the ship.

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