Popular Science Monthly 



763 



To Keep the Water in the Aquarium 



Clean and Fresh 

 Ax aquarium for the lioiue ina>' he 

 M~\ ctiuipiied witli a simple contrivance 

 for keeping the water clear and fresh, 

 thus overcoming the only difificulty in 

 maintaining one. The aerator shown 

 works simply and will go for months 

 without other attention than to provide 

 water for the suppK' basin. 



In the drawing showing the apparatus 

 there are the fish 

 tank, suppl>' 

 basin, and glass 

 tubing from the 

 basin to the 

 tank. The si- 

 phon forces a 

 supply of air 

 through the 

 water in the fish 

 tank. The tank 

 consists of a 

 baseboard which 

 is slightly larger 

 than the tank itself, 

 four square posts and 

 four pieces of heavy 

 glass. The base piece 

 should be cut from 

 wood I in. thick. Screw 

 two strips of wood 

 across it on the under 

 side, one at each end, to 

 pre\"ent it from warping. 



The corner posts are 

 to be shaped as shown 

 in the drawing with a 

 rebate for the glass on 

 the adjacent sides and 

 a piece fitted in the 

 inner angle to hold the glass in position. 

 The base is also grooved* on the sides 

 and ends for the glass. Fit the posts by 

 sinking them intoa J/4-in. mortise cut in 

 the base piece and then put a long 

 screw into the end of the post througli 

 the base piece. 



In fitting the glass bed in place use 

 white lead putt>' made up with a little 

 powdered rosin to cause it to harden 

 quickly. The wood of the tank should 

 be \arnished and allowed to stand for 

 one week before the tank is filled. 



The aerating apparatus is made from 

 J^-in. glass tubing with a piece of ?4-in. 

 tube for the air-recei\cr and two corks. 



An aquarium with an automatic 

 supply basin and an aerator. 



The ^4-i'i glass tube is 7 in. long and is 

 fitted with a perforated cork at each 

 end. A hole about j § in. in diameter is 

 filed in the side of the glass. 



Fit the 34-'n- pieces of tube through 

 the corks, one at each end. Take the 

 lower piece, which should be about 

 3K ft- long, heat one end of it and 

 form into a slightly bell-mouthed shape. 

 The lower end is also heated and 

 bent as shown in the illustration. 



The upper piece of glass, which shtnild 

 be of a con\enient length, is bent in 

 he form of a s\phon. F"or the supply 

 basin use a glass jar. 



After all the parts of 

 the aerating apparatus 

 have been fitted to- 

 gether, fill the fish tank 

 and put the aerator in 

 position; fill the supply 

 basin also nearly to the 

 top with clear water. 



The upper part of 

 the li-in. glass tubing 

 is now taken out of the 

 cork, and filled with 

 water, holding a finger 

 on each end. Then 

 slip one end of the tube 

 into the supply basin 

 and the other through 

 the cork of the air- 

 receiver. 



If this is correctly 

 done, it will be found 

 that the water begins 

 at once to drop from 

 the upper pipe, taking 

 its supply from the 

 basin on the wall 

 bracket, and before very long it will 

 be forcing a supply of air through the 

 water in the tank at regular intervals. 

 — John Y. Dunlop. 



Making a Serviceable Fireless 

 Cooker 



THE cooker illustrated on the follow- 

 ing page can be made with two 

 or more pots, although the drawing 

 shows only one. The outer part of a 

 double boiler will serve for the pot. The 

 first requirement is a stout box of suitable 

 size, with llie cover hinged. To prc\cnt 

 warping, it should be reinforced with 



