12 



PEESH-WATER AQUARIA. 



preferable) the length and breadth of the tank (inside measure- 

 ments), place it on the ledge which is rvmning round the lower 

 part of the frame inside, and solder or cement it there. The 

 glass for the sides should be Jin. thick, and long enough to go 

 quite across from end to end. But the glass for the ends ought 



liG. 19. Four Pieces op Zinc Moulding Joined Together, thus forming 

 either the Top or the Bottom of Frame for Aquarium. 



just to touch the glass in the sides, so helping to hold it in its 

 place. Before putting the glass into the frame its bed ought 

 to be painted with gold- size, and then covered with a thinnish 

 coating of cement. Recipes for several kinds of cement are 

 given at the end of this chapter. But, for an aquarium of this 



<x 



Fig. 20. Position of Zinc 

 Moulding when Framed. 



Fig. 21. A, Zinc Frame; 

 B, Glass; C, Cement. 



kind, a mixture of red and white lead is recommended. Now 

 put the glass in, and press it gently into its place. Put the 

 sides in first. Paint all the comers with gold-size, and then fill 

 them in with cement to the depth of about Jin. (Fig. 21). "When 

 the cement has been roughly put into position, the fixing of it 



