DEEP-SEA EXPLORATION. 
347 
disengaged, not only from tlie toothed gears, but also from the double screw, which 
leaves it free to travel by the in’essure of the wire rope upon its sides. 
The engine receives steam from the main boilers and exhausts it into the main 
condenser or into the atmosphere, as desired. 
THE GOVERNOR. 
The hoisting engine being located on the main deck and the reeling engine on the 
deck below, entirely hidden from view, it became necessary to have some automatic 
device by which the movements of the former would govern those of the latter. For 
this purpose the governor (plate xxix) was devised by the writer. It maintains 
jiractically uniform tension on the dredge rope between the hoisting and reeling- 
engines by causing the speed of the latter to conform to that of the former. 
The reeling engine was located on the berth deck to lower its weight in tlie ship 
and to protect it and its appurtenances from the weather. 
The (lovernor consists of the sheave u, within the iron frame />, which moves freely 
on horizontal axes fore and aft, allowing the sheave to revolve in any plane in 
conformity with the angle of the dredge rope. The foi'ward motion of the frame h is 
checked and governed by the spring/, which is adjusted by the nut e and screwbolt (j. 
On the after end of the frame h is a connection to an arm of a bell crank d, which, 
through the connecting rod h, actuates a pressure-regulating valve (cut 61) on the 
steam pqie between the throttle valve and reeling engine. 
This valve was introduced at the suggestion of Chief Engineer Baird, U. S. 1ST., as 
more effective than the original plan of attaching the bell crank directly to the throttle 
