AQUARIUM CONSTRUCTION 215 



The frame being trued up, it is now bolted through the base, 

 aquarium cement being liberally supplied in the bolt holes and 

 between the frame and the base, all surplus being immediately wiped 

 away. 



Soldering. The ordinary amateur is equipped neither with the 

 facilities nor the experience to use a soldering iron to advantage. 

 The author has engaged in considerable aquarium construction and 

 has usually been able to get along very well without an iron, its main 

 use being to clear surplus solder away more quickly than can be done 

 with a file. Before soldering, the surface is properly prepared by 

 scraping and the application of a flux composed of hydrochloric acid 

 which has dissolved as much zinc as possible. An alcohol blow-torch 

 is satisfactory for small work, but for the heavier construction a gaso- 

 line torch is better. When the heat is applied and the liquid of the 

 flux has boiled away, touch the heated surface occasionally with soft 

 solder wire. Apply a little more heat after first sign of melting, with- 

 draw flame and proceed to quickly solder. Where work is in a posi- 

 tion so that it is difficult to hold the pieces steadily in place while 

 solder cools, an assistant can instantly "set" it by pouring on a little 

 water. Small "C" clamps are most useful in holding uprights and side 

 frames together while soldering. They may be obtained for twenty-five 

 cents or less. If acid flux darkens the hands where it touches, the stain 

 can be removed by dilute ammonia water. 



Small Aquaria. Very compact, neat and substantial aquaria can 

 be made in the foregoing manner, but without projecting base — in 

 fact, without slate at all. The bottom is self-contained concrete. 

 The top frame and upright corner posts are of j4-inch angle brass, 

 and the bottom frame of 1-inch size. In the inside edges of bottom are 

 soldered a few brass screws. Now prepare a mixture of one part of 

 Portland Cement to two of clean sand, brought to a thick, mushy 

 consistency by addition of water. Lay the frame on a good, flat piece 

 of glass and pour in the cement to a depth of ^ inch, seeing that it 

 lies smooth, particularly where the aquarium glass is to rest. 



After the cement is poured and smoothed, it should be covered 

 to be allowed to dry slowly. In about two days the frame and base 

 can be slid off the glass. The screws soldered on inside will always 

 bind the concrete base securely in place. To prevent free chemicals 

 washing out of cement into the aquarium water, it is well to water- 

 proof the inside of base before setting glass in. This may be done by 

 melting chips of paraffine on the concrete under a blow-torch. 



