PRINCIPLES OF NAVAL ENGINEERING 



MAGNETIC COI 



BREAKAWAY PIN 



VALVE STEM 



VALVE SEAT 



INLET 



PLUNGER 



ELECTRICAL 

 CONNECTIONS 



MAGNET 



BELLOWS 



TO 

 THERMO- 

 BULB 



PISTON 



^OUTLET 



CONNECTOR 

 ROD 



—SPRING CAP 



SPRING 



47.98 



Figure 19-10.— Solenoid valve (top) and thermostatic control switch (bottom). 



The saturation point is usually called the 

 dew point. If the temperature of saturated air 

 falls below its dew point, some of the water 

 vapor in the air must condense into water. The 

 dew that is visible in early morning after a 

 drop in temperature is the result of such con- 

 densation. The sweating of cold water pipes is 



the result of water vapor from the air condensing 

 on the cold surfaces of the pipes. 



The amount of water vapor in the air is ex- 

 pressed in terms of the weight of the water 

 vapor. This weight is usually given in grains 

 (7000 grains : 1 pound). Absolute humidity is 

 the weight of water vapor (in grains) per cubic 



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