Here is one family of spiderlings upon the grape-vine spray, for instance. They are hanging several yards above the water, and with an ocean, as it were, between them and the distant country upon which their hearts are set. But there is no hesitation or misgiving. Let us closely observe this eager youngster far out upon the point of the leaf. The breeze is blowing across the brook. In an instant, upon reaching the edge of the leaf, the spiderling has thrown up the tip of its body, and a tiny, glistening stream is seen to pour out from its group of spinnerets. Farther and farther it floats, waving across the water like a pennant. Two, three, five, ten, fifteen feet are now seen glistening in the sun. Now it floats in among the herbage upon the opposite bank, and seems reaching out for a foothold. In a minute more its tip has brushed against a tall group of asters, and clings fast, the loose span sagging in the breeze, and as we turn our attention to the spider, we see that he has turned about, and is now "hauling in the slack," which he continues to do until the span is taut, when he anchors it firmly to the leaf, and without a moment's ceremony steps out upon his tight-rope, and makes the "trial trip" across the abyss--a feat which Dr. McCook, the spider specialist and historian, has most felicitously compared to the similar trial trip of Engineer Farrington across the cable of the East River Bridge, a thrilling event which was witnessed by thousands of spectators from sailing craft and housetops. Our spider has now reached the asters twenty feet away, and is doubtless busying himself by further securing the anchorage at this terminus. It is quickly done, for see, he is even now far out over the water on his return trip, arriving at the grape leaf a moment later. His strand is now three times as strong as at first, and will be many times stronger before he is satisfied with it. An hour later, if we care to go up-stream half a mile to the bridge, or half a mile below to the crossing pole, for the sake of examining those asters across the brook, we shall find our spiderling nicely settled in a tiny little home of his own. The glistening span is now like a tough silken thread, and is moored to the head of flowers by a half-dozen guy-threads in all directions, while in their midst, in the "nave of his tiny wheel of lace," our smart young baby rests from his labors. Such is the probable course which he would follow, unless, perhaps, his roving spirit, thus tempted, has further asserted itself, and not content with this exploit, he has concluded to span the clouds, and is even now sailing a thousand feet aloft in his "balloon." As a bridge-builder he has had many successful imitators, but as a balloonist he is yet more than a match for his bigger copyist, _homo sapiens_, as I shall explain in a subsequent paper. Ballooning Spiders