It follows then that in making their original plan the different thicknesses of every honeycomb must be fixed upon, and at the same time the alley-ways which separate each must be different in turn, and this width must be twice the height of a bee since they have to pass each other between the upright combs.
But even the bees are not infallible, and they do not always work with exact mechanical certainty. When they find themselves in a difficult place they sometimes make very great blunders. One often finds that they leave too much, and often too little, space between the honeycombs, and they remedy these faults as well as they can--sometimes in finishing the comb which is too near another in an oblique line, or sometimes when they have left too much space they interpose a smaller comb between it.
Réamur, on this subject, says:--"Since bees sometimes make mistakes and rectify them, this must be a proof that they possess the power of reason."
It is known that bees make four different kinds of cells. There are first the "royal cells" which are exceptional and are of acorn shape. Then there are the large cells in which the male bees are reared, and in which provisions are stored when the flowers furnish forth of their abundance. Then there are the little cells which may be called the "cradles of the working bees," which are also employed as ordinary store-rooms. These generally occupy about eight-tenth's of the total surface of the combs in a hive; and finally there are a certain number of what may be called transition cells. Although these latter are inevitably irregular, the dimensions of the second or third type are so well calculated that when the decimal system was first established, and people were seeking an incontestable standard of measurement, it was the cell of the bee which was proposed first of all by Réamur. Each one of these cells is an hexagonal tube placed upon a pyramid form, and each honeycomb is formed of two strata of these tubes, base to base, in such a way that the three lozenges which make the pyramid-like base of one cell form at the same time the pyramid-like bases of the three cells on the other side.
[Illustration: WORKER.] [Illustration: DRONE.]