"Air bubble" Quotes from Famous Books
 ... was to hold the sub to the depth of water desired. This was the diving-rudder man, a most expert one, we were told, who had been known to hold a submerged sub at full speed to within six inches of one depth for two miles at a stretch. A thin brass scale and a curved tube of colored water with an air bubble in it helped out the diving-rudder man's calculations. The least deviation of the sub's course from the horizontal and these two instruments, lit up by electric lamps, showed it at once. There was a big ...
— The U-boat hunters • James B. Connolly |
