Correspondence 



203 



A DEVICE FOR CONTINUOUS SUPl'LY OF FRESH WATER. 



Sir. — As a coii.stant supply of fresh water is so important for the 

 health of the occupants of our aviaries, I think that a descrij)tion of an 

 arrangement I have made in my small aviary may be of possible interest to 

 some of my fellow memliers, as the contrivance attains the desired object 

 with a minimum of trouble. 



My very rough sketch shows a vertical section of the water-trough 

 with the inlet and outlet pipes as follows : 



E. 



C 



H. 



A. Ivilet Pipe. The flow of water is regulated by a tap outside the aviary. 



B. Perforated pipe across the middle of top of the trough. As the perfora- 

 tions represent less than the section of the inlet pipe, the water comes 

 through them with a greater pressure and gets well sprayed all over 

 the trough and its contents get properly stirred up. 



Outlet Pipe. Bent as shown in .sketch, so that the top of the bend should 

 be a little lower than the top of the trough ; this level (D) prevents the 

 latter overflowing when the j^i'essure is turned full on. 

 Is the level corresponding to the lower part of the bend of the outlet 

 pipe. When the water is allowed to trickle slowly through pipes A and B 

 it will overflow slowly also, and the level of the water in the trough will 

 keep at the level of the said point C, while being constantly renewed. 

 The continuation of the ♦outlet pipe must be brought, say a couple of 



feet below the level of the trough. When the water is allowed to flow 

 through A and B fast so that it should rise to level D, the air is driven 

 out of the bend, pipe H acts as a syphon and the whole trough empties. 

 It will continue working through till the tap is closed ; if the tap is set 

 at a certain point — which experience quickly shows — the trough will 

 automatically fill and empty itself continuously. 



At this point a small pin hole is made in the lead exhaust pipe ■ its 

 function is to ensure the air being driven out and the syphon acting, and 

 also to help the continuous filling and emptying. If it gets choked, the 

 syphon, once started, is apt to continue even with very little dripping into 

 the trough, too little water to make the syphon act if the trough is 

 already at level C. 



Liverpool, August 20, 1917, P. J. CALVOCORESSI. 



