CHAP. V. | DEEP-SEA SOUNDING. 2D5 
the vanes. The revolving axis communicates its 
motion to the indices on the dial-plate c, which are 
so adjusted that the index on the right-hand dial 
passes through a division for every fathom of 
Fig. 43.—‘ Massey’s’ Sounding Machine. 
vertical descent, whether quick or slow, and makes 
an entire revolution for 15 fathoms, while the left- 
hand index passes through a division on the circle for 
15 fathoms, and makes an entire revolution during 
Q 
