Popular Science Monthly 



455 



fastened together and held in place by 

 two pieces, or strips, 3 in. wide by i in. 

 thick. One piece is nailed along the 

 top and the other along the edge on 

 front and sides. ____^ 



The gates are 

 made from 2-in. 

 square material 6 

 ft. high, swung 

 between posts 

 made of studs. 

 At the top of 

 each gate is 

 placed another 3 

 by I -in. strip; 

 as shown in the 

 illustration. Each 

 pen is provided 

 with a running- 

 board on each 

 side. This is 6 in. 

 wide and i in. 

 thick, placed 5 ft. 

 from the ground 

 where it is carried 

 on wooden brackets 



2x4. 



'x3' 



^RUNNING eOAP O 



^^aflACE. 



/'xa' BASEBOARD 



Detail of the supports 

 and rvmning boar d in fly 



The whole fly is 

 covered with wire netting, preferably of 

 i-in. mesh. The 2-in. mesh is good but 

 it allows sparrows to get in. 



This house, if properly built, will 

 accommodate 200 pairs of breeders with 

 ease. The cost should be ver>' moderate 

 and it has every good feature which could 

 be demanded in a modem squab house. 



Locating Electric Conduits in 

 Old Walls 



WHEN necessary to find a conduit 

 for rep lirs or removal, the tearing 

 up of flooring or plaster is un- 

 avoidable if the location is not 

 marked. To do this quickly and 

 with little trouble, use the or- 

 dinary compass. Locate the 

 cable as near as possible, then 

 place the compass close and 

 keep it on the move until the 

 needle will not deflect in either 

 direction. The cable will be 

 found directly beneath the 

 compass when the needle stands 

 in this position. It is necessary 

 to have a current flowing 

 through the wires in the cable 

 to produce the magnetic field 

 for moving the compass needle 

 as there is nothing in the cable sheath to 

 cause it to turn, most sheaths being made 

 of insulating materials and not metal. 



A Concrete Letter Box in the 

 Form of a Post 



THIS concrete letter box is like a 

 large concrete fence post with a 

 hole in the top and a hinged lid to cover 

 the opening. It has been used for years. 

 It does not leak, it looks good, and will 

 last forever. 



Make the molds of wood. The under- 

 ground portion of the letter box should 

 be at least two or three feet deep to a 

 solid footing and below the frost line. 

 The outside dimension of the square 

 concrete is 12 in. and it need not taper. 

 If desired, the exposed corners may be 

 be\eled with an edger. The hole in the 

 top is 8 in. in diameter and 14 in. deep. 

 A hea\y bolt is placed in one corner of 

 the top of the post so that the lid can be 

 swung upon it. Reinforce the corners 

 with ^^-in. round steel rods running the 

 full length of the letter box, which is 

 about 3J^^ in. above the grade line. 



In the mixing of the concrete, if un- 

 screened ''bank run" gravel is used, it 

 should be mixed in the proportion of 

 one to four. Crushed rock or screened 

 gravel and coarse sand are better for 

 concrete work, and if such materials are 

 available use a one-two-four mixture for 

 the buildings of this simple but durable 

 letter box for the farm. Tamp the sides 

 of the forms lightly so as to remove the 

 air bubbles in the concrete and force the 

 gravel towards the inside. L'se an old 

 piece of 8-in. drain tile for making the 

 hole in the top which will hold the mail. 

 The cover is made of concrete and is 

 reinforced with a wire netting. A round 



The letters are dropped into a hollow in 

 what resembles an ordinary hitching post 



metal pin fastened in the cover fits in 

 a hole in the post top to provide a way 

 for swinging it from over the hole. 



