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A swimming pool lined with the glazed tile referred to above is shown 

 in Fig. 1, Purdue University Memorial Gymnasium. 1909. 



In addition to the outlets for the water in the bottom of the pool, it 

 is advisable to have, at the overflow point, a sufficient number of outlets, 

 or a trough extending all around the pool, so that when a scum or dirt 

 collects on the surface of the water, the upper layers may be drawn off 

 without necessarily emptying the whole pool. 



Fig. 2. Men's Swimming Bath, Leeds, England. (Lighted by sky-light only.) 

 By courtesy of "Modern Sanitation." 



The floor of the pool room should be so drained that water dripping 

 from bathers "who have come out of the pool can not collect in puddles, 

 and, furthermore, such water should drain, not back into the pool, but 

 into the overflow waste pipes. 



The Water Supply. 



The water supplied to the swimming pool must be pure, and every 

 possible means used to keep it so during and after its use by the bathers. 

 The nearest approach to an ideal water supply for an indoor swimming 

 pool would be the provision for a pure water to start with, and a continu- 

 ous change of water, during the use of the pool, the rate of this change 

 being governed by the number of bathers in the pool. In most cases this 

 is out of the question on account of the expense. 



The water of these pools is not exposed to the many purifying fac- 

 tors that affect out-door waters. The pool is usually located in the base- 

 ment or in buildings the interior of which the direct rays of the sun 

 seldom reach. Thus one of the most important factors in the purification 

 of natural waters is removed. It is true that the water does get some 



