CONSTRUCTION TANKS AND POOLS 



223 



metal and has no bottom, it being impossible to withdraw a bucket on 

 account of suction. 



Another added attraction for those caring for the aesthetic side 

 is the addition of tiles in the edges. To try to push these into the 

 finishing coat is to court certain trouble and a botch job. As soon as 

 the concrete is poured the tiles should be set on little mounds of 

 cement as indicated in Figure 205, seeing that they come to exactly 



Mm^^x 





s j; 



Fig. 205 



Fig. 206 



Fig. 207 



Fig. 205. Tile set on cement mound. Fig. 206. Top finishing coat brought to 

 level of form. Fig. 207. Guideboard in position for inside finishing coat. 

 (Whether or not tiles are used, this is the best method of finishing.) 



the right level, fixing the four corner ones first. Next day the finish- 

 ing coat is filled around them, and they help to establish the correct 

 level. The cement will slop over on them a little, but this is no mat- 

 ter. Most of it can be wiped off with water, and the balance after 

 drying, with dilute hydrochloric acid. 



The author is not partial to drain-pipes. They may become dis- 

 lodged and let the tank run dry, or, on the other hand, they may get 

 sand in them and not go back into place. However, this is a matter 

 of personal preference. When the tank must be emptied, it is easily 

 done by siphoning with a garden hose carried to a lower point. See 

 page 228. In two days after the finishing coat is applied, a little water 

 may be run in. On the fourth day fill completely. 



Seasoning Cement Tanks. All cement containers should be sea- 

 soned before the fishes are introduced. This can be done by chang- 

 ing the water six times over a period of two weeks. This is not 

 thorough and a longer time is better. Seasoning can be accelerated 

 by different chemical processes. The safest is to fill the pool and 

 slake a large piece of lime in it. In a pool 8x12 feet, slake about 

 half a bushel. There is no danger of using too much. After slak- 

 ing, stir every few hours and clean out thoroughly in two days. 

 Another method is to place a piece of blue litmus paper (obtainable 



