NATURAL BRIDGE

BY

SUSPENSION.

The Chain and Rope Bridge is an inven-tion of mountainous countries, and of veryearly times. The spider, travelling fromtree to tree on a slender bridge of this kind,of her own manufacture, may have suggest-ed it; and, perhaps, the subject may be bestillustrated by a reference to this bridge-builder of nature’s own tuition. The spider,about to construct a bridge of this kind,turns one of her nipples, which she canraise and depress at will, to the wind, anddarts a thread with an elevation and force,and of a thickness proportionate to the dis-tance of the place to which the projectedend is intended to be attached : the one end■of the thread she then fixes, and the otherend becomes fixed accidentally, accordingto the direction of the wind. The thread

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