138 



Popular Science Monthly 



width of the seam must be added to the 

 edges of the developed pattern. This may 

 be added in two different ways. Add a sin- 

 gle width on the edge of one pattern and a 

 double width on the edge of the other 

 pattern. The other way is to divide the 

 three-seam widths in half and add the same 

 allowance on each pattern, which would be 

 one and a half times the width-of the seam. 

 Wherever there is a corner in the seam 

 or wire allowance the metal must be cut 

 out or "notched" as shown in the illus- 

 tration. This is done so that the ends of 

 the wire or seam allowance will come 

 together neatly. 



A Pin Inserted in a Cork to Make 

 an Oil Dropper 



IN oiling fine machinery, clocks, watches, 

 etc., too much oil is often used. Light 

 oil flows so freely that it 

 is difficult to get just 

 enough out of the spout 

 of an oil-can and to put 

 it in the exact spot where 

 it is needed. A needle 

 inserted in the cork of an 

 oil-bottle will be found to 

 pick up just a drop of oil. 

 This drop will be carried 

 on the point of the needle 

 and can be deposited ex- 

 actly where desired. Care 

 must be taken not to dip 

 the needle too deep in 

 the oil or there will be 

 more oil clinging to its sur- 

 face than the single drop needed for a 

 bearing. — W. H. Sargent. 



Picking up a drop 

 of oil with a pin 



An Automatic Watering Tank for 

 Poultry Yards 



MANY types of automatic tanks have 

 been invented to provide fresh clean 

 water for .the fowls all during the day. 

 Several of these must be tipped upside 

 down in the process of filling. 



The accompanying sketch presents a 

 type of tank in which the water may be 

 poured in through the top. The tank can 

 be made of galvanized iron. A small 

 faucet, A, is placed near the bottom so 

 that it will open beneath the surface of the 

 water in the dish, B. The cover must fit 

 tightly to make an airtight joint when it 

 is screwed down. To do this a broad 

 shoulder is left at C so that the gasket 

 rubber D will have a firm foundation. 



The following procedure is necessary in 

 filling the tank: Close the faucet, A, re- 

 move the screw cap, E, and pour the water 

 in at the top. The lid is then replaced and 



A reservoir from which fresh water is au- 

 tomatically supplied to the poultry yard pan 



the stop-cock, A, opened. The water will 

 run out until the level in the dish, B, 

 comes just above the opening of the faucet. 



A Trough for Thoroughly Washing 

 Film Negatives 



A SPECIAL trough for washing nega- 

 tives will be found a great convenience 

 to the photographer who uses films. The 

 trough here illustrated is nothing more than 

 a long, water-tight box, made of galvanized 

 sheet steel, having a drain cock fitted at the 

 bottom of one end and with a small piece 

 of tubing soldered at the top of the other 

 end to hold a length of rubber tubing or 



~*" A galvanized iron washing tank for rapidly 

 removing all traces of chemicals from films 



hose for making connection with a faucet. 

 The trough is 40 in. long, 7 in. wide and 

 5 in. deep. 



In use, the trough is placed in a level 



