Have you ever thought, when looking at the web of a spider, what an admirable piece of work it is, and how this thread is manufactured? No lace is more beautifully worked. The thread is formed by a semi-liquid secretion, which comes out, at the will of the spider, through minute apertures, and which hardens into a thread by contact with the atmosphere.
How strange that is!
Spiders must have a great amount of knowledge, and are, no doubt, good barometers, for when a storm is impending they never will build or mend a web. There is a good reason for their not being extravagant in the use of their silk, for, although they can use at their will the secretion from which the thread is made, it requires time to reproduce it; so when you see a spider spinning new webs, it is a sign of fine weather coming.
If you look closely at the web of a spider, you will surely be surprised at their wonderful skill. First a net-work of strong threads is built; these are the main beams, and between them the net made of smaller thread is spun. These webs are exceedingly elastic, for they have to resist the power of the wind. When the web has been long built, and has become stretched, they will sometimes go and fetch a little piece of wood, which they hang by a thread, and haul it to a spot where they think it will steady their structure.
The threads of spiders are produced from an organ called the "spinneret," which is placed at the extremity of the body. The spinnerets are arranged in pairs, and are four, six, or eight in number.
The spider generally works at its web with its head down, lowering itself by its thread. The whole is worked by the sense of touch, the threads being guided by one of the hind legs. If you take the trouble to watch a spider working, you will see it work just as I have described.
The semi-liquid secretion is forced out through very small apertures, which may be called miniature tubes; they look very much like very minute hairs. These tubes cover the spinnerets, which are externally like little rounded projections, but their shape is not always the same. The threads become quite strong, for after leaving the tubes they are united together, and hence are much stronger than if the thread was composed of a single strand.
