WAX, AND BEE ARCHITECTURE. 163 



venience of convex bases on the other, like, indeed, 

 the bottoms of those bottles which are made to look 

 large and hold little — the very opposite of a principal 

 requisite in comb structure ; but equal concavities 

 are given on both faces, by the cell walls of one 

 surface coinciding with the adjacent edges of the 

 rhombs, which diverge from the centres of the cells 

 on the other (see A) — an arrangement easily under- 

 stood by noting that the single lines dividing the 

 rhombs in B indicate the lines of the cell walls on 

 the remote side of the comb, while the double lines 

 indicate the cell walls on the near side. The same 

 fact may also be made apparent by piercing three 

 pinholes through the several rhombs of the base of 

 any cell, when these holes will be found to belong 

 to three different, though adjacent, cells of the 

 opposite face. Anyone really desirous of thoroughly 

 understanding this, and the other points yet to en- 

 gage us, will do well to make, in cardboard, the form 

 given at D, where all the obtuse angles (marked or 

 0), and the acute (marked a), are equal to one another 

 respectively; the sides (s), if extended as far as the 

 edge of the letterpress, giving the correct proportions. 

 The dotted lines being half cut through, the form will 

 fold into two cells thrice natural size, and in correct 

 relative position on opposite sides of the comb, when 

 the edge 1 will fall on i', and the other numbered 

 edges meet as indicated. Designing a more com- 

 plicated form, including two cells on each side, and 

 cut out in one piece, is an interesting, and not 

 excessively difficult, puzzle. Strips of gummed tissue 

 paper will hold the cells in form, which, when made 



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