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Show THE SPEED OF INSECTS. The Flj Itktt Six Haa4r4 Stroke a knnl Itkca la Harrj. There are many insects which one would little suspect to be furnished with apparatus suited to swift and more or less continuous flight. House flies frequent the inside of our windows, win-dows, buzzing sluggishly in and out of the room. But what different creatures crea-tures are they when they accompany your horse on a hot summer's day. swarm of these little pests keep pertK naciously on wing about tho horse's ears; quicken the pace up to ten or twelve miles an hour, still they are there; let a gust of wind arise, and carry' them backward and behind, the breeze having dropped, their speed is redoubled, and they return to their post of annoyance to the poor horse even when urgod to its fastest pace. But this example gives only a partial par-tial proof of the fly's power of flight, as the following will show: The writer was traveling one day in autumn by rail at about twenty-fivo miles an hour, when a company of flies put in an appearanco at the car window. They nevor settled, but easily kept pace with the train; so much so, indeed, that thoir flight seemed to bo almost mechanical, and a thought struck tho writer that they had probably been drawn into a sort of vortex, whereby they were carried onward with but little exertion exer-tion on the part of themselves. But this notion was soon disproved. They sallied forth at right angles from the train, flow to a distance of thirty or forty feet, still keeping pace, aud then returned with increased speed and buoyancy to the window. To account for this look at the wings of a fly. Each is composed of an upper and lower membrane, between which tho bloodvessels and respiratory organs or-gans ramify so as to form a delicate network for the extended wings. These are used with great quickness, and probably six hundred strokes are made per socond. This would carry the fly about twenty-five feet, bui a sevenfold velocity can easily be attained, making mak-ing one hundred and soventy-five feet per second, so that under certain circumstances cir-cumstances it can outstrip a racehorse. It a small insect like a fly can outstrip a rjcehorso, an insect as large as a horse would travel very much faster than a cannon ball. |