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hound did after fox; making short semicircular casts, and all the time rapidly vibrating its wings and antennæ. The spider, though well concealed, was soon discovered; and the wasp, evidently still afraid of its adversary's jaws, after much manoeuvring, inflicted two stings on the under side of its thorax. At last, carefully examining with its antennæ the now motionless spider, it proceeded to drag away the body?'

The species of which we have yet spoken are strictly solitary in their habits; indeed, we question whether all spiders are not the same in this respect, being only brought into proximity by favourable locality or abundance of food. Mr Darwin, however, states that he found, near St Té Bajada, many large black spiders, with ruby-coloured marks on their backs, having gregarious habits. 'The webs,' says he, 'were placed vertically, as is invariably the case with the genus Epeira. They were separated from each other by a space of about two feet; but were all attached to certain common lines, which were of great length, and extended to all parts of the community. In this manner the tops of some large bushes were encompassed by the united nets. Azara has described a gregarious spider in Paraguay, which Walckenaer thinks must be a theridion, but probably it is an epeira, and perhaps even the same species with mine. I cannot, however, recollect seeing a central nest as large as a hat, in which during autumn, when the spiders die, Azara says the eggs are deposited. As all the spiders which I saw were of the same size, they must have been nearly of the same age. This gregarious habit in so typical a genus as Epeira, among creatures which are so bloodthirsty and solitary that even the two sexes attack each other, is very singular fact.'

The singularity of the webs of several foreign species has attracted much attention. In Java, some of these are said to be so strong and tough that they are not easily divided without a knife, and in this case quite capable of entangling not only insects, but birds and small quadrupeds. In the Cordilleras, Mr Darwin found nets constructed after the manner of those of our garden-spider; but instead of all the rays being netted, only two were woven together, so that the web was of a wedge-shape. Perhaps the most ingenious exhibition of networking which we have read is that of an Australian spider, related by a correspondent of the Zoologist for January 1846: 'In the middle of last April I was particularly struck with the singular habits of a spider, which had constructed his web between a high fence and the gable-end of my house [in Sydney]; these being about ten yards from each other, and the web being about midway between them. As soon as the web was finished, the spider procured a leaf, and having rolled it up in the form of an extinguisher, he fixed it in the very centre of the web, with the point upwards. In this domicile he remained at rest until some prey was entangled in the web, when he immediately pounced upon it, and conveyed it to his mansion to be

devoured. Whether the object of this singular contrivance was protection from the weather, or concealment from his prey, or both combined, I am unable to say; but it struck me as very ingenious. Had the domicile been placed at the extremity of the lines, the spider would have had at least five yards of line to traverse before reaching the centre of the web, and of course the same distance to return with his prey. One wet and windy night spider and all disappeared.' With the exception of the Javanese spiders, all that we have yet mentioned weave comparatively small and slender fabrics. This is not the case, however, with a Brazilian spider noticed by Dr Walsh, and apparently the same with the large Epeira found by Mr Darwin in the neighbourhood of Rio de Janeiro; at least both weave strong yellow webs, and have semi-gregarious habits. The doctor's account of it is as follows: 'Among the insects is an enormous spider, which I did not observe elsewhere. In passing through an opening between some trees, I felt my head entangled in some obstructions, and on withdrawing it, my straw-hat remained behind. When Í looked up, I saw it suspended in the air, entangled in the meshes of an immense cobweb, which was drawn like a veil of thick gauze across the opening, and was expanded from branch to branch of the opposite trees, as large as a sheet ten or twelve feet in diameter. The whole of this space was covered with spiders of the same species, but different sizes; some of them, when their legs were expanded, forming a circle of six or seven inches in circumference. They were particularly distinguished by bright spots. The cords composing the web were of a glossy yellow, like the fibres of silk-worms, and equally strong. I wound off several on a card, and they extended to the length of three or four yards.' Sir James Emerson Tennent tells us of a spider of Ceylon-the Olios Trapobanius-very common in that island, and remarkable for the fiery-red hue of its under surface, that it spins a moderate-sized web, hung vertically between two sets of lines, stretched one above the other athwart the pathways.' 'Some of the cords,' he adds, 'thus carried horizontally from tree to tree at a considerable height from the ground, are so strong as to cause a painful check across the face when moving quickly against them; and more than once in riding I have had my hat lifted off my head by a single line.' One cannot read these accounts without concluding that such a product, if found in abundance, might be successfully applied to some economical purpose. Indeed, the application of spider-web has already been attempted, with various success, to the manufacture of a kind of silk, of which we shall now give some

account.

SPIDER-SILK.

The idea of obtaining silk from the produce of the spider occurred first, we believe, to Reaumur, who for that purpose collected the eggbags or cocoons, and not the webs, of the common garden-spider.

Having obtained, with some trouble, thirteen ounces of these bags, he had them beaten and washed, to free them from extraneous impurities. After this they were steeped in a solution of soap, nitre, and gum-arabic, and then boiled in the same mixture over a slow fire. Clean warm water was then used to free them from the soap, &c.; and having been laid for some days to dry, they were loosened with the fingers previously to being carded by the common silk-carders. By this process a beautiful ash-coloured silk is said to have been obtained, easy to be spun, and much stronger in the thread than that of the silk-worm. This was woven in a stocking-weaver's loom. The thirteen ounces of bags yielded about four ounces of silk, three of which were sufficient for the manufacture of a pair of stockings. This experiment fully demonstrated the capabilities of spider-silk; but the impossibility of obtaining abundance of the raw material precluded any further application of the discovery. Naturally, the substance is concealed, or torn and scattered about in insignificant quantities; and to rear spiders artificially, as we do the silk-worm, has been found impossible, in consequence of their hostile and ferocious natures. Reaumur placed 5000 in fifty different cells, and fed them on insects and proper juices; notwithstanding, the larger devoured the smaller, till in a short time only two or three were left in each compartment.

More recently, a gentleman of the name of Rolt received an honorary medal from the London Society of Arts for obtaining silk from the produce of the same spider. In Mr Rolt's experiment, the silk was obtained directly from the spinnerets of the animal, and not from its egg-bags or cocoons. He connected a small reel with the steam-engine of the factory in which he was occupied, and putting it in motion, at the rate of 150 feet per minute, found that a fullgrown spider would thus continue to afford an unbroken thread during from three to five minutes. The specimen of this silk which Mr Rolt presented to the Society was wound off from twenty-four spiders in two hours. Its length was estimated at 18,000 feet, its colour was white, and its lustre of metallic brilliancy, owing probably to its great opacity. Mr Rolt did not attempt to combine two or more filaments into one winding, nor to form it into thread by throwing. The thread of the garden-spider is so much finer than that of the silk-worm, that the united strength of five of the former is, according to Mr Rolt, equal only to one of the latter; and assuming that the weight is in proportion to the strength, and that a spider will yield twice a year a thread 750 feet in length, while that produced by a single silk-worm is 1900 feet, it follows that the produce of one silkworm is equal to that of 6 spiders. 'Now,' says the Report in the Society's Transactions, 'as on an average it takes 3500 silk-worms to produce a pound of silk, it would take about 22,000 spiders to produce an equal quantity. Besides, spiders are not so easily confined as silk-worms, and whenever two come in contact, a battle

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ensues, which ends in the destruction of the weaker one. Spiders kept for silk must therefore be each in separate dens or cells; and the apparatus contrived by Mr Rolt for this purpose, though very ingenious, and well adapted to carry on a course of experiments with a hundred or two, would manifestly be wholly inapplicable to any purpose of commercial utility.' Such has been the result of the experiments to obtain silk from spiders. The scantiness of the produce, the impossibility of rearing the animals in communities, and, above all, the difficulty of supplying them with food, leave little or no hope of amendment.

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Strange as it may seem, spiders have otherwise had, or still have, some economical importance attached to them. Medicinally,' says Hentz, 'the web is narcotic, and has been administered internally in some cases of fever with success.' The web of the common housespider has long been employed in stopping the effusion of blood. Good Master Cobweb,' says Bottom, if I cut my finger, I will make bold with thee.' Though spiders are regarded by us with aversion, there are savage tribes who eat them. Sparman says that the Bashie men consider them as dainties; and Labillardière asserts that the inhabitants of New Caledonia seek for and devour large quantities of a spider nearly an inch long, which they roast over a fire.

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WAS born on the 24th of July 1687, in Crutched Friars, London, where my father then lived; but soon after, he removed to the Old Jewry, near Cheapside, where he kept, for several years afterwards, that noted house called the King's Head, a famous beef-steak house in its day, and a great resort of merchants and other gentlemen. Reared in London, and often about the Thames, I acquired an unconquerable desire to go to sea; and though my parents did everything in their power to give me a good education, and promised to push me on in the world, if I would abandon this notion, I persevered in my obstinate resolution. Not all the entreaties of my poor dear mother, though she once begged me on her knees, nor the persuasions of my father or any other friends, could make the least impression on me.

When they found their endeavours were ineffectual, they formed a new scheme to wean me from a sea-life. This was to procure me a short voyage, hoping that the many dangers and hardships to which I should be exposed, and should see others undergo, would deter me from persevering in that course of life.

As wilful persons never want woe, such was my obstinacy, that

No. 36.

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