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The mandibles of the great crab spider, Wood says, are so large that they 
are removed from the creature and set in gold and used as toothpicks as they are 
believed to possess virtue enough to drive away the tooth-ache. 
The most serious obstacle in making the silk of spiders useful is that the 
creatures themselves are such dreadful cannibals, which makes it practically an 
impossibility to keep them. Place a large (or any) number in a box, and they 
will soon be reduced to one or two. Finding, a long time ago, some very pretty 
spiders, and not knowing anything about them, I put them in a box, covered it 
with gauze, and gave them some flies; but, though they had the flies, they preferred 
to eat each other, and the flies were not touched. The survivor was in such a 
mangled state I killed it. 
It has been estimated that 27,648 females are required to make one pound of 
silk, whilst 2,304 silk-worms will make the same weight. True, instances are 
recorded of spiders’ silk having been turned to account. Louis XIV. had a dress 
made of it; but its want of strength soon disgusted him, though the silk of some 
of the American spiders possesses power of strength to admit of its being made use 
of. Al D’Orbigny had a pair of trousers made of it, which lasted a long time. 
Next, a Mr. Rolt received a medal from the Society of Arts for obtaining silk from 
the garden spider. The gossamer was obtained directly from the spinnerets, and not 
from the egg, or cocoon silk. He connected a small reel, with the steam-engine of the 
factory in which he was engaged, and putting it in motion at the rate of 150 feet 
per minute, found that a full-grown spider, would, during from three to five 
minutes, continue to give an unbroken thread. The specimens of this silk which 
Mr. Rolt presented to the Society, were wound off from 24 spiders in two hours. 
Its length was calculated at 18,000 feet, the colour white, and the lustre was of 
metallic brilliancy, owing most likely to its great opacity. 
In 1797 a work was published by Quatre Mére Disjouval on Arachnology, 
or the art of interpreting weather, from changes in the webs and motions of the 
spiders. The author had beguiled the weary hours of his imprisonment by watching 
the movements and proceedings of spiders, as connected with atmospheric changes, 
and had thus obtained the materials for his work. And in times more recent, Una 
bella ragna on his dungeon wall became the pet of Silvio Pellico, and was thus 
useful, so to speak, in providing consolation to the mind of the unhappy 
prisoner. 
In Jamaica, spiders are encouraged in dwellings, since they are found to be 
very useful in keeping under the cockroaches ; and a humorous gentleman, living 
in London, writes in Science Gossip that he keeps a spider in his bedroom to kill 
the pestilence that walketh in darkness. It has heen observed, that the female epeira 
has completed her ten changes of skin inaboutsix months (one of which takes place in 
the cocoon) and at the end of eight months she is 2,700 times as heavy as she was at 
her birth. The slough is cast in the most perfect condition, with every hair, the 
fangs, the feelers, the legs with all their joints, and even the cornee of the eyes, 
It can be examined readily, and-with a good cleaning and drying makes an excel- 
lent object for the microscope. The moulted skin can generally be found close to 
