128 



SEASON 1874-75. 



ciple is very great, and the advantages of grilles are yet but 

 little understood. This will be treated of more fully hereafter 

 (Fig. 70). 



FIG. 70 -scale i. 



The next point in the hatehing-boxes was to introduce the 

 water ; and here I had several failures. The first idea was to let 

 the water fall on a sheet of perforated zinc (Figs. 71, 72, 73). 



Fio. 71 scale 



Fio. 72 scale -f,. 



FIG. 73 scale &. 



This had answered so well in the leaf-screen, I did not see any 

 objection. But I soon was undeceived. The water on the small 

 sheet behaved abominably. The very excellence of its power of 

 keeping the sheet free slopped half the water on the floor when- 

 ever the supply was increased. This in frost meant the floor 

 one sheet of ice at Middlethird. 



Fio. 74 scale ^. 



FIG. 76 scale 



