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fecm occupied only with ministring to those thai po-< &sh. They are always at hand to furnish them with) honey, or other fluid substances that are necessary both for their work and their sustenance.
Each comb is composed of two rows of cells laid dose to each other, the base of each i*ow being common. The thickness is something; less than an inch -r the depth of each cell therefore will be about five lines. I have often observed that a comb a foot in length/ had from sixty to sixty-six cells. According to this proportion, the width of each cell will be a* little more than'two lines, which is nearly a third of * its depth : this measure k that of almost all the cells in the hive; there is but a small number larger: the width of these is somewhat more than three lines, and the depth a little more than lix. These large cells are destined to contain the larvæ of the drones, which we (hall afterwards mention. We find besides in different places of the hive, three or four cells larger than the rest,, and of a different figure. The mouth of these is in the underside j they are attached to the extremities of the comb, and have the figure of a spheroid. They are supposed to be the habitation of the queens j. but I confess I have never been able to ascertain this point.
The base of the combs is at such a distance from One another that when the cells are finished there is rio more space between two combs, than is sufficient to allow two bees to pass back to back. The combs are not continued quite from top to bottom, but are often interrupted; there are besides certain openings at different distances which allow a communication from one to another, both easier and shorter.
After having explained the manner in which Bees construct their cells, I find it necessary to be more
particular with regard to their figure. The base ot each cell is formed of three rhombs, as we have already said, almost always equal. According to the measurement I have made os them, each of the obtuse angles, is no degrees, and each of the two acute ones is consequently 70. These three rhombs are inclined to one another, and are joined by the fides which form one of the obtuse angles. The mutual inclination of these rhombs makes a solid angle, which: on account of the general uniform equality of the rhombs, is situated in the axis or centre of the cell. The six other fides of the fame rhombs, besides three obtuse angles form likewise three other angles by the: reciprocal inclination, which forms their junction at the two acute angles. These six equal sides of the three rhombs are so n any bases on which the bees elevate the walls which form the six sides of each cell. Each of these walls is a trapezium which has one acute angle of 70 degrees and an obtuse one of an hundred and ten; the two angles of the trapezium which are at the mouth of the cell are right angles.We must observe here that the acute angle of the trapezium is equal to the acute angle of the rhomb at the base, and the obtuse angle of the same rhomb is equal to the obtuse angle of the trapezium. The six trapeziums which form the six sides of a cell join one another at equal sides, and are connected to the rhombs of the base; thus the obtuse angles of the rhombs are contiguous to the obtuse angles of the trapeziums, and the acute angles of these last to the acute angles of the former. Such is the structure of each cell.
T come now to the manner in which the two ranges of cells constituting the comb are formed, and the way in which the cells are joined together. Imagine to yourself in the first place, several other bases similar to those we have described; suppose farther, these bales to be applied to one another in such
ynanner that the similar angles of the one shall correspond to the similar angles of the other, and shall join together exactly. In such a case two of these bases being joined to a third, three rhombs of these three disferent bases will form the bottom of a new cell similar to the first, with this only difference, that the concavity of the solid angle is turn'ed to the other side of the comb, where there is another range of cells opposite to the first. By the junction of six bases with a seventh, there will be formed three new bases, which will have the concavity of the solid angle also turned ip a contrary direction to that of the seven bases. Lastly the twelve new bases united to the eight preceeding ones fo^m nine others with the concavity of their angle opposite to that of the twelve. By this wonderful structure are formed the two ranges of combs. Thus there are three lines of Thombs on three different planes, so well executed that several thousands of rhombs of the fame line all reft on the fame plane. Is it not truly surprising then, that so many thousands of animals, aided by natural instinct alone, should agree together in forming a work so difficult, with so much order and regularity?
Bees do not give their cells so determinate a structure without design. I have fait} .that each base is formed of t.ree rhombs, and that on each fide of these rhombs there is a wall which serves as aside to the opposite cell. Those three walls, besides serving as a side to part of a cell, likewise serve for a support to the base of the opposite cell, and lupply the detect arising from the great tenuity of the work- Moreover, the concavity of the solid angle which is in the middle of the base, serves by an admirable effect of divine providence to collect into a small space the particles of honey, which the Bees daily furnish to the little larvæ, as I shall afterwards shew. If the bottom had not been disposed in this manner, the honey which is at
O^ first sirst fluid, would have run out, and the enibrio would have perilhed for want. It is not the figure of the bottom onl/ which is favourable, many advantages arise from the number or angles in the rhombs. On the size of them depends that of the angles of the trapeziums which form the six sides of the cell. Now, as the acute angles of the rhombs are 7c0. 32' and the obtuse ones 109° 28' those of the trapeziums contiguous to them, must be of the fame degrees respectively. Besides, by this number cf angles in the rhombs, the solid angle of the base is equal to each of the three solid angles made by the obtuse angle of the rhomb, with the two obtuse ones of the Trapeziums ; from this greatness of the angles, therefore, there results not only a greater simplicity in the work and greater facility for the Bees, who thus make use, pf only two sorts of angles, but likewise greater symmetry in the disposition and figure of the cell.
The figure which Bees give to their cells is a re? gular. hexagon. Pappus, a celebrated Geometrician of the second century, has observed that it looked as if these little animals had a particular acquaintance with geometry, when they gave such just proportions to their cells. Nor could they have chosen a figure. wh}ch would have afforded them a greater number ot cells in the space contained in their hive. The property of this figure is that many united together completely sill up a space round a certain point without leaving any void whatever. The same property belongs to two pther figures, to wit, the equilateral triangle and the square. But neither of these have the capacity of the hexagon. It is therefore with great wisdom, continues the same.Geometrician, that Bees make use of that in preference to every other figure. For if the same quantity of matter is employed in the construction of a triangle, a square, and a hexagon, this last will contain more honey than the others. The
The second example of industry and sagacity in insects shall be taken from wasps, these animals construct their-nest, either in the earth, or suspend it from some new building: They do not begin their fabric like Bees at the top; but like ordinary architects they lay their foundation, and raise the superstructure in the cornmon way. The nests of all the species are not of the fame shape. Some are of the figure of an oblong, some of an oblate spheroid; some are conical, with the apex irregular and truncated, something like that of certain sea shells, and some resemble a1 bottle with a long neck. The cells in the greater number of wasp-nests are hexagonal, and surrounded externally with a white integument of a woody substance resembling the dry pods of kidney-beans; The upper part of this integument . serves as a roof to the whole edifice; it secures the' nest from humidity, which in running along it, might incommode the wasps. The sides serve as walls to defend the inhabitants from injury; and the under part is as it were a base to the whole fabric; if the integdment is removed, the inside discovers six stories at equal distances from one another. But least one should fall and demolish those below it, each story is supported by several columns which are broad at the base, and ,grow broader again at the top, so as to form a kind of arch.
The fame elegance is hot less remarkable in the structure of those nests which are shaped like a bottle with a long neck. The external cover is thin, like transparent vellum. The learned Aldrovandus, having cut one of these nests longitudinally found it defended with three other integuments which like the first, were of the shape of a bottle, but without the neck. In the centre of all these covers, he found seven hexagonal cells.