United States. Army. Signal Corps · Washington · leaf 117
there- fore be climbed with the liquid as high as possible in the U tube. When this is being done the reading on the air-speed indicator should be taken and noted for future use. The bottle is of the vacuum type so as to prevent the difference in temperature of the air out- side affecting the air… … flask similar to that used in the instrument above has also two tubes leading out of it, one of which can be opened or closed at will and the other leading to a horizontal tube which is straight or may be slightly bent. In the middle of this horizontal tube is a drop of
Aeronautics, Military
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