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with difficulty comprehended; I have therefore thought it neceffary, to reprefent, by the annexed pate, the figures which the author defcribes.

The structure of a cell feems at first fight very complica ted, though it is made up of only two different pieces; the firft is, the rhomb, Fig. I. the obtufe angles of which, according to M.Maraldi, are each of 109o 28', and the acute ones, A and C, each of 70° 32': the other is the Trapezium, Fig. II. the fide of which, G H, is equal to one of the four fides of a rhomb; the fide, G E, equal to the depth of the cell, together with the hollow of its bafe; the angle, H, equal to each of its obtufe angles, and the angles E and F are right angles. Three rhombs, equal to that of Fig. I. form together the base of a cell, and fix of the trapeziums compofe its fides.

In order to comprehend how thefe rhombs form a base, imagine the three rhombs, I K L, Fig. III. placed on the fame plane, fo that any three obtufe angles fhall meet in one point, M; then, leaving thefe three angles in their point of contact on the plane, raise the three angles, N O P, fo that the fide, M Q fhall unite with M R, the fide M S, with M T, and the fide M V, with M X, then, from the junction of these three rhombs, thus elevated, there will be formed, the folid concave angle, Y, Fig. IV. which, turned upfide down, will be the folid convex angle, Z, Fig. V. the firit of which will be the bafe of a cell, having its mouth uppermoft, and the other, of a cell having its mouth downwards. Place, on the fix external fides, 1, 2, 3, 4, 5, and 6, of these three rhombs united at the bafe, Fig. IV. as ma ny fuch trapeziums as we have described, raised perpendicularly to the plane, so that, their acute angles fhall meet the acute angles of the rhombs, and the obtufe angles of the rhombs, the obtufe angles of the trapeziumis, which may be eafily done, by turning the fix fim lar trapeziums, one within the other, alternately outwards, then, by the union of thefe nine pieces, will be formed, the hexagonal cell, reprefented in two different tituations, Fig. VI. and VII. to give a more diftinct idea of it.

Now, to know how feveral cells are connected, imagine, in the first place, three concave bases, B A F D, B D E C, BCGA, Fg. VIII. fuch as we have defcribed, and set upon the fame plane. If you join them together, each by the obtufe angle of one of their rhombs, fo that the three

angles you have taken, fhall meet in one point, B, Fig. IX. then their fides, B A, B D, B C, will unite and become common, in the fame manner as the trapeziums which you are afterwards to raise on them, joined to the other trapeziums, placed on the external fides of the three united bales, will form three contiguous celis, as in Fig. X.

It will be easily conceived, that, by joining in the fame manner, other bafes to the three here mentioned, they will become the bottom of as many new cells as may be joined to the first, by their common fides, and this may be carried on at pleafure.

It remains to know, how the bafes of cells make part of the bafes of thofe oppofite to them. For this purpose, confider again, the three united bafes of Fig. IX. which form each a folid cóncave angle, KI H. You will fee, that, by the union of the three rhombs, A D, D C, and CA, which meet in BD, B C, B A, they confpire to form in B, a folid concave angle, equal to each of the three folid concave angles, KIH, the pofition of which is reverfed. It is this angle, B, which makes the bottom or bafe of an oppofite cell, and the fix exterior fides, AK DICH, of the three rhombs, A D, D C, C A, which compofe this angle, ferve for fupport to the fix trapeziums, which fhould be raised on them, and form by the union of their fides, a cell refting on three others oppofite to it, as in Fig. XI. where the cell is reprefented erect, the better to fhew the way in which a cell refts on three.others. And, as by joining many bafes, the angles of which are folid and concave, thefe bafes, by the junction of their external fides, likewife form convex angles, fimilar to the firft, it follows, that feveral bases of cells united, which belong to one of the rows in a comb, form by their junct on, feveral of the united bafes of the. oppofite row. Thus, in Fig. XII. the union of the feven concave bafes, A, B, C, D, E, F, G, form the convex bafes, H, 1, K, of the three oppofite celis.

To give a more diftinét idea, ftill, of the manner in which the two rows of cells in a comb, are placed on the common bafe of the comb, I have added figures XII and XIV. Fig XIII reprefents the plan of a part of the base of a comb; the hexagons, marked with dots, ind cate the pofition of the cells of one row; and the hexagons with lines, that of the other row. Fig. XIV. is a fection of the fame comb.

PAGE

PAGE 124, 1. 23.

Thefe tumours vary in appearance. These tumours are generally named galls, and are of many different k nds: the gall-nut, fo well known for its various ufes, is one fpecies of it. M. de Reaumur defcribes feveral of them, in his Memoires, Tom III. his obfervations are exceedingly curious, and deferve to be read.

PAGE 125, 1. 4.

Choose a place, where they may be fecure. That place of retreat is generally the earth; the greater part of infects, which pafs the winter without eating, and in their nymph or chryfalis ftate, retire into habitations which they make there, each in its own way.

PAGE 125, 1. 30.

Or by the mouth or abdomen. It is not properly by the mouth, that these infects fpin their webs; it is by an apparatus which they have under their mouth. Spiders, and the infects of the genus Hemerobius, draw, from the extremity of their abdomen, the filk of the coques in which they inclose themfelves. Some fpecies, likewife, of Dytisci, do the fame, in order to construct the nefts in which they lay their eggs.

PAGE 125, 1. 31.

Or by the abdomen. This is the way in which spiders extract the matter of their webs. Thofe larvæ, called by the French, Pucerons-lions, likewife draw from the extremity of their abdomen, the filk of which they make their coque, and in which they inclofe themfelves. Some species of Dytifci likewife do the fame to fabricate the coques in which they depofite their eggs.

PAGE 125.1 34.

Others are coarfer. Spiders have the power of fpinning their threads, either fine or coarfe, as they pleafe, by drawing from their bodies, as many threads as the occafion requires, and joining them together: thofe which spread their nets in gardens, can even spin two forts of threads, the one glutinous, the other not: this we can affure ourselves of, by throwing dry fand on their web: we fhall find, that the

fand

fand will stick only to those threads that turn fpirally, but will by no means adhere to those that run straight across the web.

PAGE 126, 1. 12.

As fkilful dyers. It is not in the option of infects, to paint or vary the colours of their filk, at their own pleasure: this depends on the nature of the filky matter which is formed in their entrails. It is this, and not the infect, which gives the colour to their thread. Befides, what is said here, of the beauty of thefe colours, is applicable, only to a few of these animals; the filk which most of them spin, is of a very ordinary colour, and much inferior to that which a good dyer could give them.

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The wife form of government. What authors have advanced, on the conftitution and government of bees; on the authority of their king; on his fkill in the art of reigning, on the obedience paid by his fubjects, and on many other things of this nature, is fo fine, fo marvellous, that it ccafes to be probable. Suppofe thefe circumftances to be nothing but ingenious fictions, as there is every reafon to believe, it would not be difficult to trace their origin. People have at first admired the art with which bees conftruct their combs and have, from that, conceived very high ideas of them: they have feen them living in fociety, and labouring in various ways for the common good; from this it would be inferred, that they have laws and established ranks having found in their fwarms, fome bees larger than the reft, thefe would be confidered as kings; feeing thofe furrounded by a number of other bees, thefe would be courtiers or guards, or fubjects coming to receive orders, and to execute them; in a word, no particular has been obferved, in the economy of bees, that has not received an interpretation conformable to the high ideas conceived of them, and to the monarchical fyftem, under which it feemed certain, that they lived. But, what would be our furprife, when, after having attended more closely to the behaviour of this king, and having dared, even to lay hands on his facred perfon, to find his body full of eggs, and to fee his principal occupation, that of laying thefe eggs in the empty cells! From thefe circumftances, unprejudiced per

fons

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