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Popular Science Monthly 



A Novel Color Mixer for Teaching 

 Blending Effects 



AVERY simple and novel device for 

 illustrating the various color effects 

 produced by mixing different paint pig- 

 ments can be made in the follow- 

 ing way : 



Prepare a series of pigment 

 "matches," as shown in the illus- 

 tration. This can be 

 done by obtaining the 

 soluble pigments in dif- 

 ferent colors and making 

 each into a thick paste 

 by mixing with a little 

 glue. Dip the end of a 

 match stick into the 

 pigment and when the 

 adhering mixture dries, 

 mount it on a card- 

 board with one or two 

 other similarly prepared 

 "matches." When 

 these are immersed in a 

 cylinder of water, the 

 pigments at once dis- 

 solve, and as they inter- 

 mingle, the true color 

 effects of the mixed pig- 

 ments are at once ap- 

 parent. This is by far the best method yet 

 employed for teaching color effects to a 

 class of pupils. 



Yellow dipped match 



lever. 



RecTatpped 



' :n 



Pigment "matches" dissolved in water to 

 show the effects of blending different colors 



Employing Deadly Gases Against the 

 Sleeping Sickness Fly 



N British East Africa great annoyance 



Shoe- Shining by Electricity in a 

 Self-Elevating Chair 



ANEW shoe-shining machine, invented 

 by Otis R. Hasty, of Elgin, 111., is a 

 combination of an ordinary chair and an 

 electric elevator. You mount the 

 chair at practically the normal 

 height. The bootblack throws a 

 An electric motor drives 

 some gearing which 

 raises a rack-pinion con- 

 stituting the supporting 

 column of the chair. 

 The foot rest is rigidly 

 connected with this col- 

 umn, so that it rises at 

 the same time. 



After rubbing on the 

 paste, the bootblack 

 plugs a short flexible 

 cable to a shaft jutting 

 out at the bottom of the 

 machine. The shaft 

 which is geared to the 

 motor also, imparts its 

 rotation to the flexible 

 cable and to the cir- 

 cular buffer at the «;nd 

 of the cable. The buf- 

 fer speeds around and 

 brushes your shoes in a twinkling. Such 

 little time is required for the operation that 

 one bootblack can attend to two patrons 

 at a time, polishing the shoes of the first 

 while the paste on the second pair is 

 "setting." 



I 



species closely allied to the ordinary 

 house-fly, but which in that locality 

 is considered particularly dangerous 

 to health. In New Langenburg, a 

 district recently acquired from the 

 Germans, it has been impossible to 

 maintain horses, cows or cattle of any 

 description on account of the mor- 

 tality caused by the diseases which 

 the flies are said to carry. 



The extermination of the flies has 

 therefore become a matter for Govern- 

 mental consideration. The latest 

 suggestion awaiting experiment is the 

 use of gases, poisonous to the flies. 

 These, it is believed, could be carried 

 across the fly-infested areas by the 

 monsoons, in the same manner as 

 the destructive gases are carried in 

 trench warfare. 



You don't have to be an athlete to climb into this 

 chair. An electric motor raises you to the proper height 



