U-tube 1 of the chamber is filled with mercury, the level being at the same height in both branches. In measuring linear acceleration, the column of mercury in tube 1 is displaced by inertia, thereby displacing the water on top of the mercury. This forces a certain additional amount of water into one of the elastic tubes, 2 or 3. The deformation of these tubes, caused by the change in pressure, is transmitted by intermediate link 6, connected by turning pairs B and C to link 4 and to lever 5. Lever 5 turns about fixed axis A, and its hand a has a pen which records the readings of the instrument on a paper chart fastened to drum 7. Drum 7 rotates about fixed axis D. The motion of the hand depends upon the measured linear acceleration.
$4073$EHP,M$