Popular Science Monthly 



383 



Cleaning the Air Fed to Automobile 

 Engine Cylinders 



OF interest to every 

 automobilist, and to 

 the Government whose 

 army trucks run in con- 

 voys almost hidden in 

 clouds of dust, is the car- 

 bureter air-cleaner shown 

 in the illustration below. 

 The device is distin- 

 guished by its simplicity; 

 for it has no moving parts. 

 By extracting the dirt 

 and grit from the* air 

 sucked through the car- 

 bureter into the engine 

 cylinders, excessive wear 

 on pistons and piston 

 rings is avoided, as well 

 as scoring of the cylinders, 

 pitting of the valves and cutting out of 

 bearings. 



The cleaner operates on the principle of 

 centrifugal action. The air is sucked in 

 near the top and down through the two 

 curved square - sectioned 

 tubes. The circular path 

 of the air down through 

 the tubes throws the 

 heavier particles of 

 dust to the out- / 

 side so that . 



when air and A,rm 

 dirt are sucked 

 through the ends of 

 the tubes, the dirt drops 

 down on to a cone- 

 shaped shield in the 

 bottom while the air passes 

 up and out through the 

 center of the top to the 

 engine cylinders. The dirt 

 slides down off the cone 

 into a pocket beneath, 

 which is cleaned out as re- 

 quired when the engine is 

 stopped. 



Another point in favor of 

 such a cleaner is that it 

 reduces the carbon forma- 

 tion. The dried out lubricant 

 remaining in the cylinder 

 after each explosion attracts 

 the particles of dirt usually 

 sucked in with the fuel air, 

 forming points on which 

 carbon readily collects. 



In circle: Smoking the rifle sight for use when firing in 

 the sunlight. Above: Using the rifle strap as a sling-grip 



Some Rifle-Firing "Kinks" That Are 

 Taught the West Pointers 



THE average recruit who starts in at 

 West Point knows as much about the 

 fine points of rifle firing as a long- 

 shoreman about flying. First he 

 masters the elementary steps — 

 the manual of arms and the cor- 

 rect firing positions. Then he 

 must learn a thousand facts not 

 mentioned in the "Drill Regula- 

 tions." Among the rifle kinks, 

 for instance, is the smoking of the 

 glass rifle sights for work in 

 the sun. By simply holding 

 the sights over the flame 

 of a match — or better, over 

 an alcohol flame — a light 

 layer of lampblack is spread 

 over the sight which enables 

 the soldier to fire even when 

 he is directly facing the sun. 

 And when his back is to- 

 wards the sun, the reflected 

 glare is eliminated so that he 

 can work without danger to 

 his eyes. 



Another kink is the doub- 

 ling up of the ordinary rifle- 

 strap in order to use it to ob- 

 tain a sling-grip. By making 

 the sling short enough, it is 

 possible for the left hand to 

 obtain a vise-like grip on the 

 rifle. This helps consider- 

 ably in steadying it. 



Air drawn to 

 carbureter' 



Dirt falls to 

 bottom 



Clean out 

 The principle of centrifugal 

 action explains the working 

 of the carbureter air-cleaner 



