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That man should display wisdom in his economy is not surprising. God hath endowed him with a rational soul, by the assistance of which he thinks, judges, reasons, and is induced to conduct himself agreeably to the inductions which flow from his just principles: but that animals deprived of the use of reason, and all infects, should exhibit so much of if in their whole economy is what surpasses our comprehension. I have already remarked a; vast number of instances of this kind which authorize us to conclude that insects act according to the rules of wisdom; but as the subject is exceedingly interesting,; I shall collect in this Chapter, the principal proofsof their sagacity.

The skill of birds in constructing their nests is so* great, that the most ingenious artist could not- exceed it. With what neatness do they notcombine: pieces of wood, and straw, and mess and clay together, in the formation of their nests! What art is conspicuous in the arrangement and disposition of each of the parts which compose them? What precautions to defend them and their young from cold! The inside of the nest is always lined with hair,

*wi(h feathers, or wool, which are disposed with such '.neatness, that every particle contributes to keep the nest warm, without in the least hurting the eggs or the young. That their nests may not be exposed to view, they are generally built in secret places; and the bird takes so many precautions to conceal them, that it is with difficulty they are discovered. In general they all endeavour to Ikreen them from danger, and from the injuries of the weather. Lastly, there are some exotic birds that interweave the slender fibrous parts of plants with so much dexterity, that they construct a round and hollow nest, which they afterwards suspend from the small branches of trees, <o put them out of 'the reach of their natural enemies.

The fame fubtilty is observable among insects. They are small and weak; but they appear great and able labourers in the formation of their nests. For <his r/urpose they collect and use all sorts of substances. Some make _ small round cases of eayh, like the nests of swallows, others form them very dex■troufly of straw or grafs. Some roll up the leaves of plants, in order to lay their eggs in them, but with so much art, that we cannot help being struck with astonilhment at it. They have various ways of rolling up the leaves, but they are all wonderful. Some use but one leaf, others several. Some Toll the leaf from the point to the base, perpendicularly to the principal nerve ; or sideVvays parallel to that nerve. These last take care to roll their leaf in such a manner that from one extremity to the other, each fold of the roil is parallel to the side of the leaf, while others roll it up like a horn, with one of the ends smaller than the other. Some only double the edge of the leaf longitudinally, making a sort of hollow hem; or if they slope much, the fold is unequal. When they roll up a part of the leaf, they P 2' six fix the roll in the shape they want it by means of different parcels of threads very artificially ranged and attached on one fide to the top of the roil, and on the other to the surface of the leaf on which it retts. It is nearly the fame when they roll up whole leave?. Each circumvolution is ccmnecteJ with that which follows it, by threads disposed like those in the former instance.

There is likewise great variety in the methods used by thole that live in society. They employ several leaves to serve them for a common dwelling. Some make them round like a pear, observing to make several holes for gates. Others join these leaves together, so that externally they have the appearance of an inverted cone, or nearly so. Among those that live solitary in a habitation composed of several leaves j some construct it of leaves separately roiled up longitudinally, and placed contiguous to one another; others make a kind of tube formed of different leaves, wound up spirally.

There are insects which though they do not roll up the leaves, yet contrive to make a habitation of them. Some rake two which they so closely connect together with their threads, that the under one serves them for a bed, the upper for a covering. They are so firmly attached to each other, that neither wind nor any other ordinary accident can separate them. Others grind the leaves and reduce them to powder, which they afterwards mix with a viscid liquor issuing out of their bodies ; and of this mixture they frame their house. Some, instead of pulverising the leaves, gnaw the wood, and use the comminuted panicles in the fame way. Same, in order to polish and give a certain consistence to their nests, use the resin of trees and shrubs; others form round {heir eggs a kind of tent \vith the threads they

draw from their bodies. In'general every different species Ihows great dexterity in collecting materials for nidification. To fee them carrying what they have selected for this purpose, one would say that they had received lessons, and that some ingenious mechanic had taught them the simplest and most convenient method of conveying these materials and using them.

The structure of different nests is not less demonstrative of the address of these insects, than, the precautions they use in placing them indicates their foresight, I mould compose a large volume, were I to enter into a compleat detail upon this head. I must therefore confine myself to a few examples of those which appear to me the most singular, 1 shall begin with the structure of the combs of Bees.

These insects begin their labours by fixing the comb to the firmest part at the top of the hive, and continue it downwards, and on both sides : and to attach it with the greater firmness, they sometimes employ a kind of wax or glue. It cannot be said with accuracy, in what manner Bees perform this part pf their work. They are in such numbers, and in such constant motion, that to the eye, every thing appears confusion. The following circumstances are however observable. These little creatures are seen parrying to the places where they are at work, little bits of wax which they hold in their claws. On their arrival, they quit their burden, fix it to the work, and mould it with their feet, sometimes on one side, and sometimes on the other. All this is performed in a very short time, after which they return to the fields, and are incessantly succeeded by others in such crowds, that the comb increases rapidly. While some labour in the construction of the cells, others are occupied only in fastening the work and giving it the due degree of consistence. For this purpose they are perpetually going over it, beating it wkk their wings, and the hinder part x>f their body. Bees construct their cells with geometrical exactness, in the following manner: They begin to term the bottom, which is composed of three rhombs or lozenges. They first make one of these rhombs and then elevate two walls, on two sides of this first rhomb. To it they join a second rhomb with a certain inclination, as we stvaH afterwards mention, and raise other two walls on two of its sides. Lastly they add a third rhomb, and raise two planes on its two exterior sides, which, with the four others, form a cell of an hexagonal figure. While one party of Bees is occupied in jthis work, another set are employed in finishing it. They retouch the sides, the angles, and base of the cells with the most scrupulous accuracy; they fasten them, and, work them so thin, that three or four of the fides laid one on another, are not thicker than an ordinary leaf of paper. But as the entrance into these cells would be too weak if it were not thicker, they make a kind of rim to it, which strengthens the entrance. By this meansthebees can come out, and go in easily, without injuring their cells, which are proportioned to the size of the body of these industrious animals.

I have said that the Bees occupied in constructing the cells, only labour for a short time at once; but that is not to be understood of those who have the ■care of finishing them. They are employed for a long time, and never quit their work, but when they carry away the little particles of wax which have been rubbed ofFin the polishing .This substance is not Jofl : there are other Bees ready to receive it, or jo go in quest of it in the cells in which those employed in polishing sometimes, for a moment, retire to deposite it; this superfluous wax is made use of elsewhere. There is a .third order of bees which

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