If a spider be put on a stick surrounded by water, she manages, in course of time, to get a thread to some object beyond, and to escape by it. To find out how this is done, Mr. Blackwall tried some experiments. He put spiders on sticks in vessels of water, and they ran up and down, unable to escape as long as the air in the room was still. But, if a draught of air passed the spider, she turned her head toward it, and opened her spinnerets in the opposite direction. If the draught continued, a thread was drawn out by it, which at length caught upon something, when the spider drew it tight, and escaped on it. If the air was kept still, or the spider covered with a glass, she remained on the stick till taken off. These experiments have been repeated, and show that the spider does not shoot or throw the web in any way, but takes advantage of currents of air, and allows threads to be blown out to a considerable distance. There is a still more curious use of this method of spinning threads; that is, in flying. Small spiders, especially on fine days in the autumn, get up on the tops of bushes and fences, each apparently anxious to get as high as possible, and there raise themselves up on tiptoe, and turn their bodies up, as in Fig. 40, with their heads toward the wind, and spinnerets open. A thread soon blows out from the spinnerets, and, if the current of air continues, spins out to a length of two or three yards, and then offers enough resistance to the wind to carry the spider away with it up into the air. As soon as she is clear, the spider turns around, and grasps the thread with her feet, and seems to be very comfortable and contented till she strikes against something. Sometimes they rise rapidly, and are soon out of sight; at other times blow along just above the ground. [Illustration: Fig. 40.] This habit is not confined to any particular kinds of spiders, but is practised by many small species of _Erigone_, and by the young of many spiders of all families, that, when adult, would be too large for it. The majority of the spiders flying in autumn are the young of several species of _Lycosa_, that seem to spend the greater part of October and November trying to get as far above ground as possible. The best places to watch them are garden-fences in cities, where they often swarm, and can be more distinctly seen than on bushes. Large numbers can always be seen, for example, on the fences around the Common in Boston, every fine day in autumn, until there has been a long period of cold weather. Other species fly in the early part of summer.