222 



GOLDFISH VARIETIES AXD 



inside and outside pressures. The lower frame of bars is bent up at 

 the ends to form a cradle, thus reinforcing the side walls. The ends are 

 finally again bent over at right angles, running in the direction of the 

 wall, and laced together. Above this are two continuous bands of the 

 steel. Figures 161 and 163 will indicate these points. The corners are 

 always the weakest points. As the concrete is poured, lay in extra 

 right-angle pieces of 12 inches total length. 



The pouring of the concrete makes a great strain on the forms. 

 These need to be thoroughly braced in the beginning, for it is impossible 

 to improvise means of looking after these points, once the work has 

 started and the walls have bulged or the corners sprung. The outside 

 bottom stakes are merely driven into the ground and not otherwise 

 fastened. Outside corners in addition to being nailed are secured by 

 pieces of tin, nailed through. Inside corners are held by iron elbows 

 (to be had at hardware stores). They are secured by screws. The nails 

 fastening side-cleats should be driven through and turned over. Concrete 

 walls had best be thicker at the bottom, putting all the slope on the inside. 

 A good inside depth for ordinary purposes is 15 inches, filling to 13j^ 

 inches with water. If an overflow is to be made through side, make a 

 core of soft wood and saturate it with water so that it will contract upon 



Fig. 163. Cross-section of Finished Pool 

 The lowest layer represents cinders. We have indicated here the upper layer 

 of re-inforcement in the base, impossible to show in Fig. 161. 



