A Non-Rewinding Film Device An Adjustable Window Screen An Electric Fly Catcher 



Window Screen on a Roller 



A practical type of disappearing roller 

 screen has been devised which can be 

 installed without a special type of frame 

 and is quite simple in construction. The 

 screen rolls into a metal cylinder two 

 inches in diameter, similar to those com- 

 monly used for house shades. On the 

 bottom of the screen is a metal slide 

 which moves in a groove on either side 

 of the window frame. 



The advantage of this type of screen 

 is that it can be rolled up out of the way 

 when not in use and is thus well protect- 

 ed in case of rain or snow storms. 



Another advantage of this screen is 

 that when it is not required when the 

 window is closed better light is ob- 

 tained. 



Electrical Fly Catcher 



A fly catcher which operates on the 

 principle of a vacuum is the latest addi- 

 tion to the sanitary forces of the "swat 

 the fly movement," as it is popularly ex- 

 pressed. Various types of mouthpieces 

 are utilized, and extensions can be made 

 in any direction to catch flies or insects. 

 The fly catcher performs a double func- 

 tion, its latter being that of an air circu- 

 lator. A moistened sponge is placed over 

 the opening of the outlet and saturated 

 with disinfectants or perfumes, as de- 

 sired. At night time an electric bulb 

 with a reflector is placed before the fun- 

 nel-like trap, for the purpose of attract- 



ing moths and other "night" insects. In 

 ordinary use in the daytime, various sorts 

 of baits are used. It has been found by 

 sanitary experts that milk attracts flies 

 more quickly and numerously than any 

 other substance. The "vacuum fly trap" 

 weighs about thirty pounds and consumes 

 as much current as a 16 c. p. carbon fila- 

 ment lamp. 



Using Kerosene to Extinguish Fires in 

 Cotton Bales 



Kerosene would not seem of much 

 value as a fire extinguisher, yet the 

 Standard Oil Company of California re- 

 cently sold a barrel of it for that purpose. 

 It put the fire out, which was something 

 water could not have done. 



The fire was inside a bale of cotton 

 in a warehouse. Cotton is packed so 

 tightly that water will not penetrate deep- 

 ly, so that, although the outside of the 

 bale may be wringing wet, the fire may 

 be still eating its way slowly through the 

 cotton inside. Kerosene is much more 

 penetrative than water, and will go to the 

 center of the tightest bound bale. 



Such kerosene soaked cotton requires 

 a higher temperature to ignite it than the 

 fire inside can reach, due to the tight 

 packing and lack of air. Consequently, 

 the fire stops when it reaches the kero- 

 sened part. After waiting a day or two 

 for the fire to burn itself completely out, 

 the bale is broken open and spread out 

 for the kerosene to evaporate, leaving the 

 unburned cotton as good as before. 



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