MOVABLE-FRAME HIVES. 



159 



they are not strong and perfectly square, the proper working; 

 of the hive will be greatly interfered with. 



324. The underside of the top-bar may be cut to a tri- 

 angular edge, which bees usually follow readily in building 

 combs. But comb foundation strips are now used almost 

 altogether, and a groove, with wedge as in fig. 69, will be 

 found very much more serviceable. Above all, the outside 

 measurements of the frames must be carefully preserved, no 

 matter what style of hive and frame we use. 



Fig. 69. 



FRAME WITH GROOVE FOR FOUNDATION. 



325. The width of the top bar has something to do with 

 the amount of bridges and brace combs (397), built by the 

 bees, between the brood-chamber and the upper stories. A 

 wide top bar, leaving but a narrow space for passage above, 

 will almost altogether prevent the building of bridges. For 

 that reason, we make our top bars l^/g inches in width. Yet 



