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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 LightHouse 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.

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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 po 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.

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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, but as a very viscid gum. This passes in little tubes or ducts to the spinners, through minute openings, in which it is drawn out into filaments,

uniting and drying instantly in the air, and so forming the single fibre from each spinner.

The silk obtained the first day was of a deep yellow; to my great astonishment, the second reeling from the same spider gave silk of a brilliant silver-white color; while on the third occasion, as if by magic, the color had changed again, and I got only yellow silk. The hypothesis of individual peculiarity, adopted the previous year to explain why some spiders gave yellow, and others white silk, was now untenable; and, remembering that, beside these two positive colors there was also (and indeed more commonly) a light yellow, as if a combination of the other two, I saw that the real solution of the mystery must lie in the spinners themselves. Examining carefully the thread as it came from the body, it was seen to be composed of two distinct portions, differing materially in their size, their color, their elasticity, and their relative position; for one of them was white and inelastic, crinkling and flying up when relaxed, and seemed to proceed from the posterior of the two principal pairs of spinners, while the other was larger, yellow, so elastic that when relaxed it kept its direction, and seemed to come from the anterior pair of spinners, and so, in the inverted position of the spider, was above the other. By putting a spider under the influence of chloroform, and then carrying the first thread under a pin stuck in a cork to one part of a spindle, and the second or yellow line over another pin to a different part of the spindle, I reeled off from the same spider, at the same time, two distinct bands of silk, of which one was a deep golden-yellow, the other a bright silver-white; while, if both threads ran together, there was formed a band of light yellow from the union of the two. Thinking such a difference must subserve some use in the economy of the insect, I made a more careful examination of its webs. At first sight these resembled those of most geometrical spiders, in being broad, rounded, nearly vertical nets; but they

were unusually large, and in their native woods often stretched between trees and across the paths, so as to be two, three, and even more, feet in diameter, and in my room at Mt. Pleasant hung like curtains before the windows. They were of a bright yellow color and very viscid; but now I noticed that neither the color nor the viscidity pertained to the entire net, for although the concentric circles constituting the principal part of the web were yellow, and very elastic, and studded with little beads of gum, (Fig 3,) yet the diverging

Fig. 3. Silk threads, viscid and dry.

lines or radii of the wheel-shaped structure, with all the guys and stays by which it was suspended and braced, were dry and inelastic, and of a white or lighter yellow color.

Now, however, a new mystery presented itself. We will admit that the spider had the power, not only to vary the size of her lines according to the number of spinners, or of the minute holes in each spinner, which were applied to the surface whence the line was to proceed, but also to make use of either golden or silver silk at will. But how was it that this yellow silk-which was quite dry and firm, though elastic, as reeled from the spider, or as spun by her in the formation of her cocoons -was nevertheless, when used for the concentric circles of the web, so viscid as to follow the point of a pin, stretching in so doing many times its length? A satisfactory explanation of this has never yet been offered, nor can be until the minute anatomy of the spinning organs is better understood, and the evolution of the silk more carefully ob

served at every stage, and under all conditions. I will merely state very briefly the few facts already established, with some of the possible explanations.

The spinning mammula are placed in pairs at the lower part of the abdomen, near its hinder end, and number four, six, or eight in different species. They are little conical or cylindrical papillæ, closely resembling the prolegs of caterpillars, and are composed of two or three joints, the terminal one of which is pierced with a greater or less number of minute holes, the sides of these, in some, if not all, cases, being prolonged into tubes. Through these holes or tubes issue the fine filaments, which, uniting as they dry in the air, constitute the line from each spinner.

Fig. 4 Spinners.

Now the Nephila plumipes possesses at least three pairs of spinners. Of these, two are much larger than the third, which indeed does not appear till they are separated. From the posterior of the two largest pairs seems to proceed the white, and from the anterior the yellow silk, while from the small intermediate pair seem to proceed very fine filaments of a pale-blue color, the use of which is to envelop the prey after it has been seized and killed, being drawn out by the bristles near the tips of the spider's hinder legs. Beside these six papillæ there is, just in front of the anterior pair, a single small papilla on the middle line, the nature and use of which I have not ascertained, though I feel quite sure that no silk comes from it. The large median papilla, just behind the posterior pair, surrounds the termination of the intestines, and through it the excrement is voided, the insect for this purpose turning back the abdomen as she hangs

head downward, so that neither the web nor the spinners shall be contaminated. Now it has recently been ascertained that the minute globules with which the circles are studded, and the number of which on a web of average size is estimated at one hundred thousand, do not exist in that form when the viscid lines are first spun by the spider, but as a uniform coating of gum upon a thread; this gum, of itself and according to physical laws, soon exhibits little undulations, and then separates into the globules which have long been observed and supposed to be formed by the spider. The fact of spiders selecting the night for the construction of their webs, the difficulty of making any close observations upon them while so engaged without disturbing them, and the near approximation of the two larger pairs of spinners while the viscid line is slowly drawn out by the hind leg, have hitherto prevented my determining its exact source and manner of formation. If it comes from the anterior pair only, then one and the same organ has the power of evolving a central axis and covering it with viscid gum; and it seems less improbable that the axis is white and formed by the posterior pair, the yellow gum being spread upon it by the anterior pair, which also would then have the power to evolve this same gum at other times as an equally dry, though more elastic thread. But in either case we have only three pairs of spinners and four kinds of silk, the pale-blue fasciculi, the dry white, the dry yellow, and the viscid and very elastic silk which is employed only in the circles of the web, and which often does not become yellow till after exposure to the light. Apparently the surest method of investigation will be carefully to destroy one pair of spinners at a time without injuring the others, and then note the effect upon the spinning.

Let us go back now to the sixty spiders left at Mt. Pleasant. A few of these died on the way North, but the majority reached Boston in safety about the 20th of September, 1865;

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for some time I had observed that they all were becoming more or less emaciated, and relished their food less than at first. Occasionally one died from no apparent cause. The mortality increasing toward the end of the month, and all of them losing both flesh and vigor, I was persuaded to try them with water, a thing I had thus far declined to do, never having heard of a spider's drinking water, and knowing that our common house species can hardly get it at all. The result was most gratifying: a drop of water upon the tip of a camel's-hair pencil, not only was not avoided, but greedily seized and slowly swallowed, being held between the jaws and the palpi. All of the spiders took it, and some even five or six drops in succession. You will exclaim, "Poor things! what tortures they must have suffered!" I admit that it could not have been pleasant for them to go so long without that which they crave every day, but I cannot be lieve that creatures whose legs drop off on very slight provocation, and which never show any sign whatever of real pain, suffered very acute pangs even when subjected to what occasions such distress to ourselves.

The few survivors straightway improved in health and spirits; but being now convinced that a moist atmosphere was almost as needful as water to drink, I turned them loose in the north wing of the hot-house in Dr. Gray's Botanical Garden at Cambridge. They all mysteriously disappeared, excepting one, which made a nice web at one end just under the ridge-pole, and for several weeks lived and grew fat upon the flies; but a thorough fumigation of the house with tobacco so shocked her not yet civilized organization that she died.

Her untimely death, however, afforded opportunity for a closer examination of the web itself. The first one she had made was not vertical; and, following the prevalent ideas as to the precise construction of the spider's web, I had felt somewhat ashamed of my pet, but supposed the next she made would be an improvement. But

no, the rebellious insect constantly made them all (for, it should have been said before, this spider seldom uses the same web more than forty-eight hours) after the same manner, and finally I laid it to a depraved idiocrasy, incident to captivity and poor health. But now another and most unexpected feature developed itself; for, on attempting to remove the last web by placing against it a large wire ring, and cutting the guy-lines, I found that this most degenerate spider had not only failed to make her house perpendicular, but had so far departed from the traditions of our ancestors as to have the centre thereof decidedly eccentric, and four times as near the upper as the lower border of the web, so that its upper portion was only a confused array of irregular lines, which it was impossible to secure to the frame. For any accurate observation my web was of no value. But perhaps this was best; for had I then learned what I have since, that our spider utterly ignores every precedent, not only in the position and shape of her web, but also in its minute arrangement, I might have been so affected by her evident bad character and radical proclivities, as to have feared paying her any further attentions, - much more, presenting her to the world.

But in order to understand how these further discoveries were made, we must again go back to the original sixty spiders in my room at Mt. Pleasant, South Carolina.

At the time of their capture, I had observed upon a few of the webs little brown spiders, which I then imagined might be the half-grown young. Six of these were found among the sixty larger spiders, and a moment's examination of their palpi or feelers (Fig. 5) showed that they were males, though even then I could not believe they had reached their maturity; for their bodies were only about one fourth of an inch in length, and weighed only one thirtysecond part of a grain, while the females were from an inch to an inch and a quarter in length, and weighed from three to four grains. It was as absurd

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