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observations, had doubtless read them in the hearing of the family. The father, gratified with this discovery of his son's talents and power of observation, and pleased with this early effort of his pen, encouraged him to turn it into the form of a letter, and to send it to his correspondent, in his own name, with an apology of his own. The apology and the account, which are copied from his own rough draught of both, in his earliest hand, after he had corrected the language of each with very great care, are contained in the two following letters; both of which, as left in the rough draught, are without the date, and the name of the correspondent, and the latter, though in the form of a letter, has not the customary form of conclusion.
"May it please your Honour,
"In the postscript of your letter to my father, you manifest a willingness to receive any thing else that he has observed worthy of remark, respecting the wonders of nature. What there is an account of in the following lines, is by him thought to be such. He has laid it upon me to write the account, I having had advantage to make more full observations than himself. Forgive me that I do not conceal my name, and communicate this to you through a mediator. I do not state it as an hypothesis, but as a plain fact, which my own eyes have witnessed, and which every one's senses may make him as certain of as of any thing else. Although these things appear to me thus certain, still I submit the whole to your better judgment and deeper insight. And I humbly beg to be pardoned for running the venture, though an utter stranger, of troubling you with so prolix an account of that, which I am altogether uncertain, whether you will esteem worthy of the time and pains of reading. If you think the observations childish, and beside the rules of decorum,-with greatness and goodness overlook it in a child. Pardon me, if I thought it might at least give you occasion to make better observations, such as should be worthy of communicating to the learned world, respecting these wondrous animals, from whose glistening web so much of the wisdom of the Creator shines. "I am, Sir,
"Your most obedient, humble servant,
"May it please your Honour,
"There are some things that I have happily seen of the wondrous way of the working of the spider. Although every thing belonging to this insect is admirable, there are some phenomena relating to them more particularly wonderful.
Every body that is used to the country, knows their marching in the air from one tree to another, sometimes at the distance of five or six rods. Nor can one go out in a dewy morning, at the latter end of August and the beginning of September, but he shall see multitudes of webs, made visible by the dew that hangs on them, reaching from one tree, branch and shrub, to another which webs are commonly thought to be made in the night, because they appear only in the morning; whereas none of them are made in the night, for these spiders never come out in the night when it is dark, as the dew is then falling. But these webs may be seen well enough in the day time by an observing eye, by their reflection in the sun-beams. Especially late in the afternoon, may these webs, that are between the eye and that part of the horizon that is under the sun, be seen very plainly, being advantageously posited to reflect the rays. And the spiders themselves may be very often seen travelling in the air, from one stage to another amongst the trees, in a very unaccountable manner.
I have often seen that, which is much more astonishing. very calm and serene days in the forementioned time of year, standing at some distance behind the end of an house or some other opake body, so as just to hide the disk of the sun and keep off his dazzling rays, and looking along close by the side of it, I have seen a vast multitude of little shining webs, and glistening strings, brightly reflecting the sunbeams, and some of them of great length, and of such a height, that one would think they were tacked to the vault of the heavens, and would be burnt like tow in the sun, and make a very beautiful, pleasing, as well as surprising appearance. It is wonderful at what a distance, these webs may plainly be seen. Some that are at a great distance appear (it cannot be less than) several thousand times as big as they ought. I believe they appear under as great an angle, as a body of a foot diameter ought to do at such a distance; so greatly doth brightness increase the apparent bigness of bodies at a distance, as is observed of the fixed stars.
"But that which is most astonishing, is, that very often appears at the end of these webs, spiders sailing in the air with them; which I have often beheld with wonderment and pleasure, and showed to others. And since I have seen these things, I have been very conversant with spiders; resolving if possible, to find out the mysteries of these their astonishing works. And I have been so happy as very frequently to see their manner of working; that when a spider would go from one tree to another, or would fly in the air, he first lets himself down a little way from the twig he stands on by a web, as
in Fig. 1; and then, laying hold of it by his fore feet, and bearing himself by that, puts out a web, as in Fig. 2, which is drawn out of his tail with infinite ease, in the gently moving air, to what length the spider pleases; and if the farther end happens to eatch by a shrub or the branch of a tree, the spider immediately feels it, and fixes the hither end of it to the web by which he let himself down, C and goes over by that web which he put out of his tail as in Fig. 3. And this, my eyes have innumerable times made me sure of.
"Now, Sir, it is certain that these webs, when they first proceed from the spider, are so rare a substance, that they are lighter than the air, because they will ascend in it, as they will immediately in a calm air, and never descend except driven by a wind; wherefore 'tis certain. And 'tis as certain, that what swims and ascends in the air is lighter than the air, as that what ascends and swims in water is lighter than water. So that if we should suppose any such time, wherein the air is perfectly calm, this web is so easily drawn out of the spider's tail, that if the end of it be once out, barely the levity of it is sufficient to draw it out to any length; wherefore if it don't happen that the end of this web, b c, catches by a tree or some other body, 'till there is so long a web drawn out, that its levity shall be so great as more than to counterbalance the gravity of the spider, or so that the web and the spider, taken together, shall be lighter than such a quantity of air as takes up equal space, then according to the universally acknowledged laws of nature, the web and the spider together will ascend, and not descend, in the air: as when a man is at the bottom of the water, if he has hold of a piece of timber so great, that the wood's tendency upwards is greater than the man's tendency downwards, he together with the wood will ascend to the surface of the water. And therefore, when the spider perceives that the web b e is long enough to bear him up by its ascending force, he lets go his hold of the web a b, Fig 3, and ascends in the air with the web b c. If there be not web more than enough, just to counterbalance the gravity of the spider, the spider together with the web will hang in equilibrio, neither ascending nor descending, otherwise than as the air moves. But if there is so much web, that its greater levity shall more than equal the greater density of the spider, they will ascend till the air is so thin, that the spider and web VOL. I.
together are just of an equal weight with so much air. And in this way, Sir, I have multitudes of times seen spiders mount away into the air, from a stick in my hands, with a vast train of this silver web before them; for, if the spider be disturbed upon the stick by shaking of it, he will presently in this manner leave it. And their way of working may very distinctly be seen, if they are held up in the sun, or against a dark door, or any thing that is black.
Now, Sir, the only remaining difficulty is, how they first put out the end of the web b c, Fig. 3, out of their tails. If once the web is out, it is easy to conceive how the levity of it, together with the motion of the air, may draw it out to a great length. But how should they first let out of their tails, the end of so fine and even a string; seeing that the web, while it is in the spider, is a certain cloudy liquor, with which that great bottle tail of theirs is filled; which immediately, upon its being exposed to the air, turns to a dry substance, and exceedingly rarifies and extends itself. Now if it be a liquor, it is hard to conceive how they should let out a fine even thread, without expelling a little drop at the end of it; but none such can be discerned. But there is no need of this; for it is only separating that part of the web b c, Fig.2, from a b, and the end of the web is already out. Indeed, Sir, I never could distinctly see them do this: so small a piece of web being imperceptible among the spider's legs. But I cannot doubt but that it is so, because there is a necessity that they should some way or other separate the web a b, Fig. 3, from their tails, before they can let out the web b c. And then I know they do have ways of dividing their webs by biting them off, or in some other way. Otherwise they could not separate themselves from the web a b, Fig. 3.
"And this, Sir, is the way of spiders going from one tree to another, at a great distance; and this is the way of their flying in the air. And, although I say I am certain of it, I don't desire that the truth of it should be received upon my word; though I could bring others to testify to it, to whom I have shown it, and who have looked on, with admiration, to see their manner of working. But every one's eyes, that will take the pains to observe, will make them as sure of it. Only those, that would make experiment, must take notice that it is not every sort of spider that is a flying spider, for those spiders that keep in houses are a quite different sort, as also those that keep in the ground, and those that keep in swamps, in hollow trees, and rotten logs; but those spiders, that keep on branches of trees and shrubs, are the flying spiders. They delight most in walnut trees, and are that sort of spiders that make those curious network polygonal webs, that are so fre
quently to be seen in the latter end of the year. There are more of this sort of spiders by far than of any other.
"But yet, Sir, I am assured that the chief end of this faculty, that is given them, is not their recreation, but their destruction; because their destruction is unavoidably the effect of it; and we shall find nothing, that is the continual effect of nature, but what is of the means by which it is brought to pass. But it is impossible, but that the greatest part of the spiders upon the land should, every year, be swept into the ocean. For these spiders never fly, except the weather is fair and the atmosphere dry; but the atmosphere is never clear, neither in this nor any other continent, only when the wind blows from the midland parts, and consequently towards the sea. As here in New-England, the fair weather is only when the wind is westerly, the land being on that side, and the ocean on the easterly. And I never have seen any of these spiders flying, but when they have been hastening directly towards the sea. And the time of their flying being so long, even from about the middle of August every sunshiny day, until about the end of October; (though their chief time, as I observed before, is the latter end of August, and beginning of September ;) and they never flying from the sea, but always towards it; must needs get there at last; for its unreasonable to suppose that they have sense enough to stop themselves when they come near the sea; for then they would have hundreds of times as many spiders upon the sea-shore, as any where else.
"The same also holds true of other sorts of flying insects; for at these times, that I have viewed the spiders with their webs in the air, there has also appeared vast multitudes of flies, and all flying the same way with the spiders and webs directly to the ocean; and even such as butterflies, millers and moths, which keep in the grass at this time of year, I have seen vastly higher than the tops of the highest trees, all going the same way. These I have seen towards evening, without such a screen to defend my eyes from the sunbeams; which I used to think were seeking a warmer climate.
"The reason of their flying at that time of year, I take to be because then the ground and trees, the places of their residence in summer, begin to be chilly and uncomfortable. Therefore when the sun shines pretty warm they leave them, and mount up in the air, and expand their wings to the sun, and flying for nothing but their own ease and comfort, they suffer themselves to go that way, that they find they can go with the greatest ease, and so where the wind pleases; and it being warmth they fly for, they find it cold and laborious flying against the wind. They therefore seem to use their wings,