516 



Popular Science Monthly 



constant figure in the run of commercial 

 freighters, and may be pretty accurately 

 estimated in the cases of other larger 

 merchant ships or well-known t-'pes of 

 naval vessels. Any coloring that will 

 tend to obliterate the actual waterline 

 or conceal or confuse the top of a 

 steamer's smokestack will deceive the ob- 

 server in his effort to determine the dis- 

 tance or range of 

 his target, and, 

 therefore, throw 

 him out in calcu- 

 lating how far 

 his torpedo must 

 travel in order to 

 score. Also, any 

 coloring that de- 

 stroys the out- 

 lines of the ship 

 and makes it hard 

 to observe her 

 movement across 

 the periscope's 

 vertical lines so 

 as to estimate her 

 speed, will intro- 

 duce another ele- 

 7zient of error. 



It has been de- 

 termined by care- 

 ful investigation 

 that the eye tires 

 in the course of a 

 minute or two 

 when watching a 

 moving target 

 steadily through 

 a periscope even 

 in broad day- 

 light; and the 

 eye so fatigued becomes 

 erratic in judging both 

 range and speed. It should 

 be evident, then, that 

 marine camouflage as we 

 have developed it in this 

 country is calculated to 

 hasten visual fatigue and 

 to so bewilder the U-boat 

 commander, when he can 

 see one of our vessels, that 

 his torpedoes will be likely to go wide of 

 their mark. We may change the old 

 adage "To err is human, to forgive 

 divine" to "To err is human to increase 

 the error is angelic" in this case. 



An arrangement that makes sure of the vapor- 

 ization of the heavier gasoline of these days 



Details of mechanism for 

 actuating the valve from dash 



Save Gasoline With Tiiis Device for 

 Controlling Engine Temperature 



GASOLINE is not what it was five 

 years ago. It is becoming heavier, 

 so that it is more and more important to 

 control engine temperatures automatic- 

 ally. Otherwise the fuel will not be 

 properly vaporized and gasoline will con- 

 dense in the man- 

 ifolds and cylin- 

 ders and destroy 

 thegreasingprop- 

 erties of the lu- 

 bricating oil. 

 The by -pass 

 arrangement 

 shown in the ac- 

 companying 

 sketches is a 

 simple way of 

 controlling the 

 temperature. 



Inside of the 

 radiator at the 

 rear is a separate 

 vertical pipe. 

 This pipe enters 

 the lower radia- 

 tor tank at the 

 bottom. An el- 

 bow at the top 

 of the pipe has a 

 plain shutter 

 valve which can 

 be opened or 

 closed so that the 

 water returning 

 from the engine 

 can be sent to 

 either the verti- 

 cal pipe or to the top tank 

 of the radiator. The 



operation of the valve is 

 controlled by the car 

 driver by means of a rod 

 and two meshing gears so 

 that in cold weather only 

 a portion of the cooling 

 water may be sent through 

 the radiator or all of it 

 through in hot weather 

 when additional cooling is required. 



This little improvement will add 

 greatly to the starting-up capabilities of 

 the car, particularly in cold weather, as 

 the gasoline is always easily vaporized. 



