Micrographia, by Robert Hooke

Observ. xliv. Of the tufted or Brush-horn'd Gnat.

This little creature was one of those multitudes that fill our English air all the time that warm weather lasts, and is exactly of the shape of that I observ'd to be generated and hatch'd out of those little Insects that wriggle up and down in Rain-water. But, though many were of this form, yet I observ'd others to be of quite other kinds; nor were all of this or the other kind generated out of Water Insects; for whereas I observ'd that those that proceeded from those Insects were at their full growth, I have also found multitudes of the same shape, but much smaller and tenderer seeming to be very young ones, creep up and down upon the leaves of Trees, and flying up and down in small clusters, in places very remote from water; and this Spring, I observ'd one day, when the Wind was very calm, and the afternoon very fair, and pretty warm, though it had for a long time been very cold weather, and the wind continued still in the East, several small swarms of them playing to and fro in little clouds in the Sun, each of which were not a tenth part of the bigness of one of these I here have delineated, though very much of the same shape, which makes me ghess, that each of these swarms might be the of-spring of one onely Gnat, which had been hoorded up in some safe repository all this Winter by some provident Parent, and were now, by the warmth of the Spring-air, hatch'd into little Flies.

And indeed, so various, and seemingly irregular are the generations or productions of Insects, that he that shall carefully and diligently observe the several methods of Nature therein, will have infinitely cause further to admire the wisdom and providence of the Creator; for not onely the same kind of creature may be produc'd from several kinds of ways, but the very same creature may produce several kinds: For, as divers Watches may be made out of several materials, which may yet have all the same appearance, and move after the same manner, that is, shew the hour equally true, the one as the other, and out of the same kind of matter, like Watches, may be wrought differing ways; and, as one and the same Watch may, by being diversly agitated, or mov'd, by this or that agent, or after this or that manner, produce a quite contrary effect: So may it be with these most curious Engines of Insect's bodies; the All-wise God of Nature, may have so ordered and disposed the little Automatons, that when nourished, acted, or enlivened by this cause, they produce one kind of effect, or animate shape, when by another they act quite another way, and another Animal is produc'd. So may he so order several materials, as to make them, by several kinds of methods, produce similar Automatons.

scheme28

But to come to the Description of this Insect, as it appears through a Schem. 28. Microscope, of which a representation is made in the 28. Scheme. Its head A, is exceeding small, in proportion to its body, consisting of two clusters of pearl'd eyes BB, on each side of its head, whose pearls or eye-balls are curiously rang'd like those of other Flies; between these, in the forehead of it, there are plac'd upon two small black balls, CC, two long jointed horns, tapering towards the top, much resembling the long horns of Lobsters, each of whose stems or quills, DD, were brisled or brushed with multitudes of small stiff hairs, issuing out every way from the several joints, like the strings or sproutings of the herb Horse-tail, which is oft observ'd to grow among Corn, and for the whole shape, it does very much resemble those brushy Vegetables; besides these, there are two other jointed and brisled horns, or feelers, EE, in the forepart of the head, and a proboscis, F, underneath, which in some Gnats are very long, streight hollow pipes, by which these creatures are able to drill and penetrate the skin, and thence, through those pipes suck so much bloud as to stuff their bellies so full till they be ready to burst.

This small head, with its appurtenances, is fastned on by a short neck, G, to the middle of the thorax, which is large, and seems cased with a strong black shel, HIK, out of the under part of which, issue six long and slender legs, LLLLLL, shap'd just like the legs of Flies, but spun or drawn out longer and slenderer, which could not be express'd in the Figure, because of their great length; and from the upper part, two oblong, but slender transparent wings, MM, shaped somewhat like those of a Fly, underneath each of which, as I have observ'd also in divers sorts of Flies, and other kinds of Gnats, was placed a small body, N, much resembling a drop of some transparent glutinous substance, hardned or cool'd, as it was almost ready to fall, for it has a round knob at the end, which by degrees grows slenderer into a small stem, and neer the insertion under the wing, this stem again grows bigger; these little Pendulums, I may so call them, the litle creature vibrates to and fro very quick when it moves its wings, and I have sometimes observ'd it to move them also, whil'st the wing lay still, but always their motion seem'd to further the motion of the wing ready to follow; of what use they are, as to the moving of the wing, or otherwise, I have not now time to examine.

Its belly was large, as it is usually in all Insects, and extended into nine lengths or partitions, each of which was cover'd with round armed rings or shells; six of which, OPQRST were transparent, and divers kinds of Peristaltick motions might be very easily perceiv'd, whil'st the Animal was alive, but especially a small cleer white part V, seemed to beat like the heart of a larger Animal. The last three divisios, WXY, were cover'd with black and opacous shells. To conclude, take this creature altogether, and for beauty and curious contrivances, it may be compared with the largest Animal upon the Earth. Nor doth the Alwise Creator seem to have shewn less care and providence in the fabrick of it, then in those which seem most considerable.

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Last updated Monday, March 17, 2014 at 16:42