180 THE HOUSE FLY DISEASE CARRIER 



make and attach the trap, with a cost of but a few 

 cents. It is made as follows: 



"Take a flat strip of tin two and one-fourth inches 

 wide and one and one-half inches longer than the dis- 

 tance between the side rail or stile and middle rail of 

 the sash, as from c to d, Fig 3, which in this case meas- 

 ured twenty-one inches. For this window, the strip 

 must be twenty-two and one-half inches in length. 

 With the tin lying on the flat surface, bend the tin 

 along the lines ab and cd, Fig. i, which are three- 

 quarters of an inch from their respective sides, so that 

 the space abdc forms the bottom of a box and the lat- 

 eral parts the sides. To close the ends, cut small in- 

 cisions three-quarters of an inch deep at the points 

 a, b, c, and d, as ay and ex, Fig. i. Bend the flaps 

 thus made at right angles to their respective parts. 

 We then have a box twenty-one inches long, three- 

 quarters of an inch wide, and three-quarters of an inch 

 deep, as at Fig. 2. 



"To make the box water-tight, solder the joints, or 

 if solder is not handy try moistened plaster of Paris. 

 When properly made, the box should fit snugly be- 

 tween the middle and side rail or style. The corners 

 should be square and the edges straight, so as to leave 

 no passageways between the box and the glass. The 

 box should rest on top of the bottom rail, and can be 

 held in place by two or three tacks or pins thrust into 

 the rail from the back side. When the pane is very 

 large it is well to attach another trap half way between 

 the top and the bottom. 



