68 PRACTICAL TROUT CULTURE. 



side removed. Fig. 15 is an enlarged view of the 

 front of the same box. At A is seen a double row 

 of coarse wire screens (three meshes to the inch), 

 eight in number. Instead of being made singly, 



FIG. 14. 



each two feet square (as usually made), they are 

 put together in one frame, eight feet by four. 

 These screens are to be filled with coarse gravel, 

 and the eggs pass through, as in Ainsworth's 

 screens. Under these is an endless apron of fine 

 wire cloth (B), passing over rollers at the two ends 

 of the box. This apron is about one inch beneath 

 the upper screen, and is kept from sagging by 

 small cross-bars (two of which are seen in the 

 cut), corresponding to the divisions of the upper 

 screen. 



These cross-bars are supported by, and, when 

 the rollers are turned, slide on an inch square strip 



