They also utilised the siphon in another way. Poising themselves just above the sand with which the bottom of the vessel was covered, they directed a stream of water upon it, and thus formed little cavities into which they settled like birds into their nests.
The figure represents the Paper Nautilus as it appears while passing through the water. Just at the base of the tentacles is seen the short siphon, from which it is pouring the stream of water which drives it along.
Below the Nautilus is seen the larva of the common Dragonfly. We have, when treating of the Lazy-tongs, already described the mode in which the insect takes its prey, and our object could not be served by repetition. Suffice it to say that the insect is shown in the act of ejecting water, and so shooting itself along in preparation for seizing prey.
Distribution of Weight.
Being on the subject of locomotion, we will examine a few of the contrivances by which a man is enabled to pass in safety over soft substances into which he would otherwise sink.
The first and best-known of these is the Snow-shoe of Northern America. It is a framework of wood, shaped as shown in the upper figure on the right-hand side, and strengthened by two cross-bars. The interior of the “shoe” is filled in with hide thongs arranged much like those of a racket, and stretched as tightly. The front of the snow-shoe is slightly turned up, so as to avoid the danger of the point sticking in the snow, an event which, however, generally happens to a novice.
These instruments are of considerable size, a specimen in my collection measuring exactly five feet in length, by fifteen inches in width.
Supported on the snow-shoe, the hunter is enabled to glide unhurt over the deep snow in which he must have sunk without some such aid. He can thus hunt the bison, the wapiti, or any of the larger animals, being able to pass rapidly over the surface, while they are laboriously ploughing their way through the snow-drifts.
It occasionally happens that the snow falls before the shoes are ready. In this case the hunter is obliged to extemporise snow-shoes by cutting them out of thin boards.