4?88 HABITATIONS OK INSECTS. 



What a surprising agreement between the solution of 

 the problem and the actual admeasurement 8 ! 



Besides the saving of wax effected by the form of the 

 cells, the bees adopt another economical plan suited to 

 the same end. They compose the bottoms and sides of 

 wax of very great tenuity, not "thicker than a sheet of 

 writing-paper. But as walls of this thinness at the en- 

 trance would be perpetually injured by the ingress and 

 egress of the workers, they prudently make the margin 

 at the opening of each cell three or four times thicker 

 than the walls. Dr. Barclay has recently discovered 

 that though of such excessive tenuity, the sides and bot- 

 tom of each cell are actually double, or, in other words, 

 that each cell is a distinct, separate, and in some mea- 

 sure an independent structure, agglutinated only to the 

 neighbouring cells, and that when the agglutinating sub- 



a Father Boscovich observes, that all the angles that form the 

 planes which compose the cell are equal, i. e. 120° : and he supposes 

 that this equality of inclination facilitates much the construction of 

 the cell, which may be a motive for preferring it, as well as economy. 

 He shows that the bees do not economize the wax necessary for a flat 

 bottom in the construction of every cell, near so much as MM. Kce- 

 nig and Reaumur thought. 



MacLaurin says, that the difference of a cell with a pyramidal from 

 one with a flat bottom, in which is comprised the economy of the 

 bees, is equal to the fourth part of six triangles, which it would be 

 necessary to add to the trapeziums, the faces of the cell, in order to 

 make them right angles. 



M. L'Huillier, professor of Geneva, values the economy of the bees 

 at A of the whole expense ; and he shows that it might have been 

 one-fifth if the bees had no other circumstances to attend to ; but 

 he concludes, that if it is not very sensible, in every cell, it may be 

 considerable in the whole of a comb, on account of the mutual set- 

 ting of the two opposite orders of cells. Huber, Nouvelles Observa- 

 tions, &c. h\ 34. 



