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man whom they could no longer endure as a king, they were contented to worship as a god.

Under the successors of Romulus the power of the state was increased, and the boundaries of her dominions extended

Numa Pomilius was elected second king of Rome in the year 714 B. C. At first he resisted the solicitations of his friends, and refused the sovereign dignity. Overcome, at length, by their entreaties and prayers, he ac. cepted the crown, and applied himself to the instruction and civilization of his subjects. During the whole of his reign he lived at peace with the neighboring states, and exerted all his powers in inspiring his subjects with a love of piety, and a veneration for the Deity. He built many temples, and so far discouraged idol worship, that it was not resumed again in the city for more than one hundred and sixty years after his reign.

For the encouragement of agriculture, he presented the poorer classes of the people with the land gained by the conquests of his predecessor : he softened the rigor of the laws, prevented the father from selling his son after marriage, judging it unjust that a woman who had married a freeman should be constrained to live with a slave: he regulated the calendar, making the year to consist of twelve months instead of ten; and he brought about a more perfect union between the Romans and Sabines. At the age of eighty-three years, after having reigned forty-three years in profound peace, he died, greatly regretted by his countrymen

(To be continued.)

DEPARTMENT OF NATURAL HISTORY.

THE GNAT.

There are few insects with whose form we are better acquainted than that of the gnat. It is to be found in all latitudes and climates; as prolific in the polar as in the equatorial regions. In 1736 they were so numerous, and were seen to rise in such clouds from Salisbury cathedral, that they looked like columns of smoke, and frightened the people, who thought the building was on fire. In 1766, they appeared at Oxford, Eng.

in the form of a thick black cloud; six columns were observed to ascend the height of "fifty or sixty feet. Their bite was attended with alarming inflammation. To some appearances of this kind the poet Spencer alludes, in the following beautiful simile:

As when a swarm of gnats at eventide
Out of the fennes of Allan doe arise,
Their murmurring small trumpets sownden wide,
Whiles in the air their clust'ring army flies,
That as a cloud doth seem to dim the skies;
No man nor beast may rest or take repast,
For their sharp wounds and noyous injuries,
Till the fierce northern wind, with blustering blast,

Doth blow them quite away, and in the oceau cast In Lapland their numbers have been compared to a flight of snow when the flakes fall thickest

, and the minor evil of being nearly suffocated by smoke is endured to get rid of these little pests.

The instrument with which they inflict their tor tures, simple as it appears to the eye, is nevertheless wonderfully complicated and ingenious: it forms a set of lancets, consisting of five pieces, enclosed in a case. This case is split from one end to the other, and, as the creature sucks, it serves to give steadiness to the instruments, while they are thrust forward into our flesh. In the first figure (fig. 1,) the lancets alone are seen enter

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ing, and their case forms an arc, supporting them. In the second, (fig 2) the lancets are perceived to have penetrated more deeply while the case, not entering, is seen to form an angle.

In order to see the whole process of suction, Reaumur courted what most others sedulously shun-a sting or two: “After a gnat had done me the kindness of settling on the hand I stretched out, I saw that it protruded a very fine point from its proboscis, with the

extremity of which it felt four or five spots of my skin. It would appear that it knows where it can pierce through most easily, and reach a large blood-vessel. Having selected a spot for its operations, it soon causes the sufferer to feel its sting.” The fine point when magnified presen is the following formidable picture,

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of which some of the detached pieces seem admirably fitted for the gnat's purpose and our annoyance. It is not however, the introduction of these points, which, when combined, are as much less in size than the finest needle, as that is than a sword, that causes the irritation which, when extended over the limb, has in some cases rendered amputation necessary—the gnat introduces a little liquid, for the purpose, as Reaumur conjectures, of rendering our thick blood thin enough to be sucked through its proboscis. To allay the effects of this poison, there seems to be no better or readier means than sweet oil, which, if applied to the wound within a few hours after it has been made, will remove the swelling, although when delayed five or six hours, it has no effect.

The gnat undergoes many metamorphoses. If water be allowed for some time to stand still in a bucket, or if a quantity of that fluid be taken from a stagnant pool, it will be found to contain innumerable aquatic insects of the following shape (fig. 1:) these are the

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larvæ of the gnat; they swim with the head downwards, a position which, to most animals, would be fa. tal; they retain the longest tube, which is their respiratory organ, on the surface. In this state they live on the contents of stagnant waters, and change their skins several times.

After having thrice got rid of its skin, the gnat appears in a new form, for, instead of being oblong, it is lenticular (fig. 2.) "The surface of the circle is vertical to the water. In this, which is its nymphine state, it is still capable of moving briskly after the manner of a shrimp, by expanding and elongating its body (fig. 3) and striking the water with the fins at its tail. In this stage of its metamorphosis, it has no organ for food, and it seems to require none; but a regular and abundant supply of air appears indispensable; it floats on the surface of the water, and only descends by efforts made with its tail. Two ears may be observed sticking out at the thickest part; these are its respiratory organs, and afford a curious instance of an important part, being removed from one extremity of the body to the other during the progress of an insect through its different stages of life.

Its last metamorphosis into a winged fly is attended with curious circumstances. When nature has prepared the insect to change its element, instead of lying rolled up on the surface of the water, it stretches out its body, and by some mechanism, puffs up its corslet so that it splits between the stigmata or the breathinghorns. As soon as the fissure is sufficiently enlarged to make way for it, the head of the gnat appears in its perfect shape; but this is the most critical period of its whole life; up to this time it was an aquatic animal; now it has nothing to dread so much as the water. It has, moreover, the use neither of leg nor wing; these members are as yet soft, moist, and bound up, and it only protrudes itself from its skin, by means of a wriggling action given to its body. If at this critical juncture the water should happen to touch its corslet or abdomen, the gnat would inevitably and instantly perish. In such circumstances, then, it requires the prudence of an old gnat, at least, to escape the dangers which surround

the young one. Nature, however, has conferred upon the insect an instinct suitable to the emergency. As soon as it puts out its head, it elevates it above the water; and worming itself out always perpendicularly, supported only by the inequalities of the skin which it is about to cast off, with no power to balance itself, surrounded by an unfriendly element, it literally becomes a canoe, of which its own bedy forms mast and sail.

The skin floats, and wl.en the observer perceives, says Reaumur, how much the prow of the little bark sinks, and how near its sides are to the water, he forgets at the moment that the gnat is an insect which at another time he would kill ; nay, he becomes anxious for its fate, and the more so if the slightest breeze play on the surface of the water; the least agitation of the air suffices to waft the creature with swiftness from place to place, and make it spin round and round. Its body, folded in its wings, bears a greater proportion to the little skiff, than the largest mass of sail to a ship: it is impossible not to dread lest the insect should be wrecked; once laid on its side on the water, there is no escape. Reaumur has seen the surface of the water covered with creatures of this kind which had thus perished at their birth. Generally, however, all terminates favourably, and the danger is over in a minute. After having stood perpendicularly, it draws out its two fore-legs, and bending to the water, places them on its surface, which is terra firma for a gnat's weight; having secured this position, all is safe; the wings dry and expand, and the insect, quitting its natal element, mounts into the air.

It is supposed, that from the end of May to that of October, six or seven generations of these insects are born, and each gnat is capable of laying two hundred

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