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HISTORY OF INSECTS. 



China, Tonquin, and other hot countries ; the 

 other is used in those places where the ani- 

 mal has been artificially propagated, and still 

 continues a stranger. In the warm climates, 

 the silkworm proceeds from an egg, which has 

 been glued by the parent moth upon proper 

 parts of the mulberry-tree, and which remains 

 in that situation during the winter. The 

 manner in which they are situated and fixed 

 to the tree, keeps them unaffected by the 

 influence of the weather ; so that those frosts 

 which are severe enough to kill the tree, have 

 no power to injure tlie silkworm. 



The insect never proceeds from the egg till 

 Nature has provided it a sufficient supply; 

 and till the budding leaves are furnished, in 

 sufficient abundance, for its support. When 

 the leaves are put forth, the worms seem to 

 feel the genial summons, and bursting from 

 their little eggs, crawl upon the leaves, where 

 they feed with a most voracious appetite. 

 Thus they become larger by degrees ; and 

 after some months' feeding, they lay, upon 

 every leaf, small bundles or cones of silk, 

 which appear like so many golden apples, 

 painted on a fine green ground. Such is the 

 method of breeding them in the East ; and 

 without doubt it is*the best for the worms, and 

 least troublesome for the feeder of them. But 

 it is otherwise in our colder European cli- 

 mates ; the frequent changes of the weather, 

 and the heavy dews of our evenings, render 

 the keeping them all night exposed, subject to 

 so many inconveniences, as to admit of no 

 remedy. It is true, that, by the assistance of 

 nets, they may be preserved from the insults 

 of birds; but the severe cold weather, which 

 often succeeds the first heats of summer,'as 

 well as the rain and high winds, will destroy 

 them all : and, therefore, to breed them in 

 Europe, they must be sheltered and protected 

 from every external injury. 



For this purpose, a room is chosen, with a 

 south aspect ; and the windows are so well 

 glazed as not to admit the least air : the walls 

 are well built, and the planks of the floor ex- 

 ceedingly close, so as to admit neither birds 

 nor mice, nor even so much as an insect. In 

 the middle there should be four pillars erected, 

 or four wooden posts, so placed as to form a 

 pretty large square. Between these are dif- 

 ferent stories made with osier hurdles ; and 

 under each hurdle there should be a floor with 

 an upright border all round. These hurdles 

 and floors must hang upon pullies, so as to be 

 placed or taken down at pleasure. 



When the worms are hatched, some tender 

 mulberry leaves are provided, and placed in 

 the cloth or paper-box in which the eggs were 

 laid, and which are large enough to hold a 

 great number. When they have acquired 

 some strength, they must be distributed on 



beds of mulberry leaves, in the different stories 

 of the square in the middle of the room, round 

 which a person may freely pass on every side. 

 They will fix themselves to the leaves, and 

 afterwards to the sticks of the hurdles, when 

 the leaves are devoured. They have then a 

 thread, by which they can suspend themselves 

 on occasion, to prevent any shock by a fall ; 

 but this is by no means to be considered as the 

 silk which they spin afterwards in such abun- 

 dance. Care must be taken that fresh leaves 

 be brought every morning, which must be 

 strewed very gently and equally over them ; 

 upon which, the silkworms will forsake the 

 remainder of the old leaves, which must be 

 carefully taken away, and every thing kept 

 very clean ; for nothing hurts these insects so 

 much as moisture and uncleanliness. For this 

 reason their leaves must be gathered when the 

 weather is dry, and kept in a dry place, if it 

 be necessary to lay in a store. As these ani- 

 mals have but a short time to live, they make 

 use of every moment, and almost continually 

 are spinning, except at those intervals when 

 they change their skins. If mulberry leaves 

 be difficult to be obtained, the leaves of lettuce, 

 or hollyhock, will sustain them ; but they do 

 not thrive so well upon their new diet ; and 

 their silk will neither be so copious, nor of so 

 good a quality. 



Though the judicious choice and careful 

 management of their diet is absolutely 

 necessary, yet there is another precaution of 

 equal importance ; which is, to give them air, 

 and open their chamber windows, at such 

 times as the sun shines warmest. The place 

 also must be kept as clean as posible ; not only 

 the several floors that are laid to receive their 

 ordure, but the whole apartments in general. 

 These things well observed, contribute greatly 

 to their health and increase. 



The worm, at the time it bursts the shell, 

 is extremely small, and of a black colour ; 

 but the head is of a more shining black than 

 the rest of the body : some days after, they 

 begin to turn whitish, or of an ash-coloured 

 gray. After the skin begins to grow too 

 rigid, or the animal is stinted within it, the 

 insect throws it off, and appears clothed anew ; 

 it then becomes larger, and much whiter, 

 though it has a greenish cast; after some days, 

 which are more or less, according to the dif- 

 ferent heat of the climate, or to the quality of 

 the food, it leaves off eating, and seems to 

 sleep for two days together : then it begins to 

 stir, and put itself into violent motions, till the 

 skin falls off the second time, and is thrown 

 aside by the animal's feet. All these changes 

 are made in three weeks or a month's time ; 

 after which it begins to feed once more, still in 

 its caterpillar form, but a good deal differing 

 from itself before its change. In a few days' 



