The Atlantic Monthly, Volume 18, No. 106, August, 1866. Various

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СКАЧАТЬ should escape and revenge herself upon my face while I was avoiding the nets of her friends, and the relentless attacks of their smaller but more venomous associates, it was the most uncomfortable walk imaginable. To complete my misery, the path led me out upon the marsh where I could see nothing of the boat or my companions, and whence, to reach them, I had to walk across the head of the island. Excepting the dreaded recrossing of the mud, I hardly remember how we made our way back; but by one means and another I finally reached Charleston at nine o'clock, about as disreputable-looking a medical man as ever was seen.

      However, all this was soon forgotten, and, being now assured of the presence of the spiders in their former haunts, on the 30th of August, 1865, I organized a new expedition, which was to proceed entirely by water, and which consisted of a sail-boat and crew of picked volunteers. Leaving Mt. Pleasant in the morning, we crossed the harbor, and were soon lost in the meanderings of the creeks behind Morris Island. Lost is appropriate, for, once in these creeks, you know nothing, you see and hear nothing, and, if you change your course, must do so by mere guess. But the most annoying thing is, after an apparent advance of a quarter of a mile, to find yourself not twenty yards from your starting-point, so tortuous are the windings of the creeks.

      By dint of hard rowing (in the wrong direction, as we soon found), then by walking across Morris Island to Light-House Inlet, and still harder rowing from there to the wharf of Long Island, we succeeded in securing sixty spiders; but now arose a furious storm of wind and rain, which not only compelled our retreat, but drenched us to the skin, blew us back faster than we could row, and threatened to overturn our boat if we hoisted the sail; so slow was our progress, that it was eleven o'clock at night before we reached Mt. Pleasant. Thus ended my last and only successful raid upon Long Island.

      It may seem that I have dwelt longer than was necessary upon the circumstances attending the discovery of this spider and its silk. If so, it is not merely because at that time both were new to myself and all to whom I showed them, and everything concerning them was likely to be impressed upon my mind, but also because I then hoped that the idea of obtaining silk directly from a living insect might be found of practical importance, as I still hope it may. The incidents illustrate, too, the nature of the obstacles daily encountered and overcome by our troops; for no one who has never seen or stepped into a Sea-Island marsh can realize how difficult it was for our forces to obtain a foothold in the vicinity of Charleston. This was appreciated by the old freedman whom we left in the boat while crossing the mud. "No wonder," he said, "the Yankees whipped the Rebels, if they will do such things for to catch spiders."

      The sixty spiders so obtained were kept for several weeks in the little boxes in which they had been deposited when caught. Every day each box was opened, the occupant examined, and its condition, if altered, noted on the cover. They generally spun a few irregular lines on which to hang, and so remained quiet except when the boxes were opened: then, of course, they tried to escape. Half a dozen of the larger ones were placed on the window-seats and in corners of the room, where they speedily constructed webs. By preference these were stretched across the windows, illustrating one of the three principal instincts of this spider, which are, first, to seek the light; second, to ascend; and third, to take a position with the head downward.

      It was now a question how they were to be fed; not so much while there, where flies were abundant, but after their arrival at the North. So, remembering that the young ones had seemed to relish blood, I took the tender liver of a chicken, cut it into little pieces, and dipped them in water, not, I am sorry to say, with any view to supply them with that fluid for the want of which they afterward perished, but in order that the bits of liver should be more easily pulled from the pins by the spiders. To my delight they greedily accepted the new food, and now I felt assured of keeping them during the winter.

      Deferring, however, a more particular account of what was observed at Mt. Pleasant, until their habits and mode of life are taken up in order, it should be understood that, during our short stay, my attention was chiefly directed to getting from the spiders as much silk as possible; for it was evident that practical men would not credit the usefulness of spiders' silk until an appreciable quantity could be shown to them. The first trial of the machine with a live spider proved it an utter failure; for though quite ingenious and complicated, it had been devised with reference only to dead spiders. In regard to the arrangement (wherein lay its chief, if not sole, peculiarity) by which a thin slip of brass was sprung against a rubber band by the latter's elasticity, with a view to secure the spider's legs between them, it was found that, as the spider was alive, and, literally, kicking, and two of its legs were smaller than the rest, these were at once extricated, and the others soon followed; while, if the spring was made forcible enough to hold the smaller legs, the larger were in danger of being crushed, and the spider, fearing this, often disjointed them, according to the convenient, though loose habit of most Arachnida, crabs, and other articulates. It was also proposed to secure several spiders in the above manner upon the periphery of a wheel, the revolution of which would give a twist to their conjoined threads, carried through a common eyelet upon the spindle; but this can be accomplished without the inconvenience of whirling the spiders out of sight, by modifications of the apparatus which has always been used for twisting ordinary silk. It will probably be inferred from the above, that, in securing the spider, two points are to be considered; first, to prevent its escape, and second, so to confine the legs that it cannot reach with their tips either the silk or the spinners. Now the machine accomplished this by putting all the legs together in a vice, as it were, entailing upon the captive much discomfort and perhaps the loss of some of its legs, which, though eight in number, are each appropriated to a special use by their possessor.

      So, abandoning the machine, I fell back upon a simple reel, and a modification of my little contrivance of the previous year; which was, to grasp the spider by all the legs, holding them behind her back, and to let her body down into a deep notch or slot cut in a thin card, the edges of which reached the constriction between the two regions of the body, the cephalothorax and abdomen; so that, when a second piece of card was let down upon it, the cephalothorax, with the legs of the spider, was upon one side of a partition, while on the other was the abdomen, bearing upon its posterior extremity the spinning organs. The head and horns of a cow to be milked are secured in a similar manner. By placing in a row, or one behind another, several spiders thus secured, a compound thread was simultaneously obtained from them, and wound upon a spindle of hard rubber.

      By this means were produced several very handsome bands of bright yellow silk; but the time was so short, and the means of constructing and improving my apparatus so deficient, that I could procure no more than these few specimens, which were very beautiful, and shone in the sun like polished and almost translucent gold; but which, being wound upon a cylinder only an inch in diameter, and from several spiders at different times, could not be unwound, and so made of any further use.

      I tried now to ascertain how much silk could be obtained from a single spider at once. It will be remembered that the first specimen, wound on Folly Island, was one hundred and fifty yards in length, and weighed one third of a grain. I now exhausted the supply of a spider for three days, using the same spindle, one inch in diameter, and turning this at the rate of one hundred and sixty times per minute. On the first day I reeled for twenty minutes, which gave two hundred and sixty-six and two thirds yards; on the third day, the second being Sunday, for twenty-five minutes, giving three hundred and thirty-three and one third yards; and on the fourth day, for eighteen minutes, giving two hundred and thirty-three and one third yards,—amounting in all to eight hundred and thirty-three and one third yards in three or four days. This was all that could be got, and the spider herself seemed unable to evolve any more; but on killing her and opening her abdomen, plenty of the gum was found in the little silk bags into which it is secreted. As this has always been the case, I have concluded that the evolution of the silk is almost entirely a mechanical process, which is but little controlled by the spinners themselves, and that the gum requires some degree of preparation after it is secreted before it is fit for use as silk; for it must be remembered that with the spider, as with the silk-worm, the silk is formed and contained in little bags or glands in the abdomen, not as threads, СКАЧАТЬ