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come too near these delicate bodies, which can hardly be touched withour hurting them. All places are riot equally sit for them; they flu:nld neither be too dry. nqr too moist, nor subject to be infested by such insects as they have an antipathy at, or which arc restless and turbulent. • Ol all exposures the least favourable are those of the north and iouth. The winds from these two quarters are exceedingly pernicious to them, the one by its coldness, the other by its humidity; for which reason, it is necessary, that the place be so disposed, as that its temperature may be regulated, by shutting the windows on one side, and keeping them open on the other, according as the wind shall blow from the north or south. When the weather is moist, it is proper to keep the place quite close; but when it lightens, that is not sufficient; the silk wcrrr.s must be covered up, otherwise they contract a disease, which some curious persons have thought proper to term jaundice. They do indeed acquire a yellow colour, lose their appetite, and die insensibly. Those th.it die, should be separated from) she living, for sear of communicating insection to them,
.CHAP. I. How.insects Hurt The Produce Of The Earth,
Not only do insects pillage and ravage the fields, but they attack man in his domestic economy, and do him infinite mischief. Nothing can be protected against their ordure; we see, with regret, our most precious furniture tarnished and infected by flits. These restless insects enter our libraiies, nestle in our cabinets, pass from . one apartment to another, and leave every where behind them, the most conspicuous 'mirks of their having been present. There is not a man, from the king to the poorest of his subjects, who can defend himself against their attacks.
Husbandmen perhaps are the most to be pitied. How often do they not find themselves disappointed of a plentiful crop by the depredations of locusts \ These voracious animals often leave distant countries, "traverse oceans, pour in myriads upon sown fields, and deprive them in a few hours of every appearance of verdure. Are not caterpillars often as noxious1 to us ? I know not a more cruel scourge for gardens than they are. They eat into flowers, they gnaw the roots, and so destroy the plants they touch, that we are obliged to throw them away. Some do not wait till a plant is able to furnish them food for weeks, they devour it the moment it appears. Others on the contrary wait till the feed is produced ; they then devour it so greedily, that nothing is left but the empty skin to the owner. Weevils are not behind hand with these; they pierce the ripe grain, eat the pulp, and thus rob our granaries of that food which is of the greatest importance to the human race.
But it is not on herbaceous plants alone, that insects bring ruin ; their attacks are not less disastrous to fruit trees. If they deposit their eggs in autumn* the young caterpillars are hatched In the Spring when the trees are only beginning to flioot forth, and they commit such ravages on the buds and foliage, that wherever they are found in numbers, the fruits of the year entirely fail. The small Curculios, some beetles and several sorts of caterpillars conspire in producing this devastation, and sometimes reduce the trees to the fame state they were in during winter. This is not all, for there are some sorts of golden coloured beetles which produce two forts of larvæ, red and white. These larvæ penetrate the bark, and suck the juice till the tree becomes completely dried up. There are also some small beetles which, not content with eating the bark, attack the wood, and contrive to desolate whole forests. This accident has but too often iappened with woods planted with pines. The wood of Schwaitzenburg experienced this to such a decree in the year 1736, as cost its proprietor many thousand crowns. I ihall content myself with this one example; thole, which 1 could adduce of many other sorts
which which destroy wood are too common not to be known by every one.
Of The Evils Which Insects Cause To Man.
We have spoken of the ravages which insects make both in the country and in towns; let us now take a view of the mischiefs they occasion to man himself personally. Some disturb his sleep, others oblige him to pass whole nights without sleeping at all. Indeed, what does he not sometimes suffer from the restless flea, and the loathsome bug? How can he take rest when unhappy enough to be exposed to the sanguinary insults of such tormen'ors? But were he free from these, the gnats do not cease to persecute him. Their inceslant buzzing disquiets him, and whether asleep or awake, while in darkness he is equally a prey to those stings which he dreads but which he cannot prevent. In the East Indies the inhabitants are exceedingly tormented by those insects which the Portuguese call Mosquitoes. These dangerous animals dart upon those whom they surprize asleep, and in such prodigious numbers that it is no easy matter to resist them. When one is stung in the face, or in any other part of the body, there ensues a considerable tumour, accompanied with itching and intolerable pain.
There is another kind of insects which arc hurtful to man by mere touch. Such is the Scolopendra ma. rina, which causes a pricking in the skin, and a heat similar to that which one seels after having touched the common nettle. Among those which render themselves formidable by their prickles, some have the hair so acute that they wound almost imperceptibly, occasioning an inflammation which quickly brings on sever; others, as the hornet and bee, strike with their sting, and though the wounded part does not bleed, it does not susser the less, and a sensible swelling succeeds. Besides these different insects there are others which like the gad fly have stings so sharp and strong that they can pierce the stun through gloves and stockings; others are remarkable by their bite like spiders; and some attach themselves to our bodies and suck the blood. The East Indies swarm with leeches, to which the Dutch have given the name of Snygers. They lurk in general among the grass, when the dew has moistened the ground, and as the country, which is intersected by rivers, torrents and swamps, obliges travellers to walk for the most part with naked seet, it happens that these animals cling to the legs and gorge themselves so with blood, that they fall off spontaneously. There are some so greedy that they thrust their head into the skin as far as the neck, and the only method of making them quit their hold, is by surrounding them with moistened gun powder, when they will come away of themselves in about a quarter of an hour or thereabouts. If a person ignorant of this expedient mould think of employing force to detach these animals suddenly, he would pay dearly for his imprudence. Not only would he experience violent pain, but a part would remain in the skin, engender an abfcess, and corrode the flesh to a great depth. 1 appeal for the truth of this to the fad experience of many persons who for several years have been subject to