50 PEESH-WATEB AQTTARIA. 



beiind it, wiU give both stade and eflEect. The back of the 

 mirror must, in some way or other, be protected from the action 

 of the snn. 



It has been ah-eady mentioned that the water of an aquarium 

 should obtain the necessary oxygen, not only directly from 

 the atmosphere above it, but also from the vegetation growing 

 within it ; but there are circumstances under which artificial 

 means of aeration should be resorted to. For instance, the 

 tank may be overstocked with fish, and their owner, unwisely, 

 be reluctant to part with any of them ; or the temperature 9f 

 the water, from some cause or other, may suddenly have risen 

 too high. I think, therefore, that a short description of some 

 of the instruments by which the water of an aquarium may be 

 artificially aerated, will not be out of place here. 



A fountain is very useful for this purpose, and is also, if 

 properly arranged, ornamental. Fig. 39 represents one which 

 may be easily and inexpensively constructed. A is a tank, 

 made of wood, slate, or zinc; but if made of the last-named 

 material, its interior should be protected from the action of 

 the water by tar-paint, or something of the like kind. This 

 tank has a spout and a tap at the bottom of one end. It is 

 placed upon the top of a bookcase or some other convenient 

 elevation, and should be hidden there if possible. B is a deal 

 table, over which there is a cover reaching down to the floor 

 of the room. is an easily-lifted can, capable of holding 

 about three gallons of water. D is a leaden or indiarubber 

 tube, joined at the upper end to the spout of the tank A, and 

 at the lower to E, which is a leaden pipe running under the 

 table and through its centre, and through that of the bottom 

 of the aquarium. The hole in the tank to receive E should 

 be rather larger than the pipe. "When the pipe has been 

 inserted into the hole, it can be fastened in its place by 

 means of little wooden wedges, and all the interstices left 

 between the wedges, the pipe, and the bottom of the tank, 

 should be tightly fiUed up with red and white lead. F is a 

 leaden waste-pipe, the lower end of which runs just through 

 the table in order that it may be inserted into the indiarubber 

 tubing (H), which will connect it with the can (C). F is fixed 



