THE HOUSE FLY 71 



When properly made the box should fit snugly between the 

 middle and side rail or stile. The corners should be square 

 and the edges straight, so as to leave no passage-ways, 

 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. 



" After the traps have been attached, some substance 

 should be put into them that will either kill the insect 

 upon falling into it, or on account of its sticky nature 

 will hold the insect so that it cannot escape. For the 

 first, kerosene, kerosene emulsion, soapsuds, and pyrethrum 

 are the best : and for the second, molasses, or a mixture 

 of castor oil and resin. For general use the soapsuds are 

 to be recommended. When using the liquids fill the traps 

 two-thirds full. 



" There should be one trap for every pane of glass of at 

 least one window in the house. For instance, when the 

 sash contains two panes of glass, as in the illustration, 

 there should be two traps, one at the base of each pane. 

 When the sash contains four panes, there should be four 

 traps, two on the bottom rail and two on the cross-bars, 

 or munting. It is not necessary to apply traps to all 

 the windows. Attach traps to one or two windows in 

 the sunny part of the house, and pull down the blinds 

 of the remaining windows. The flies will seek the lighted 

 rooms, and especially the windows. 



" When the traps are full of flies, remove them from 

 their fastenings, empty out their contents, and fill them 

 with fresh material. 



