THE FREEDOM OF THE SEAS
since they depended on a large amount of air for their performance, it was not possible to use them when submerged. When ready to sink the Diesels were stopped and uncoupled from the shafts and the motors started. These obtained their energy from storage batteries located beneath the deck on which they stood. The petty officer in charge explained the working of the contractor gear by which the control of the motors is effected in the central station. The main motors compartment, like every other section of the submarine, was painted white and was as clean as a Dutch kitchen. The electric bulbs flooded the place with light. The arching sides were crowded with switchboards and hung with a confusion of cables and wires.
Returning forward, they passed into the long compartment at that moment presided over by the diligent Clancy. The two great engines occupied every bit of space there save for a central passage barely wide enough to move through. Clancy held forth at length and with enthusiasm on those engines, but Nelson, whose bent of mind was not mechanical, found it difficult to understand what was told him. He did get away with one or two interesting facts, however: as, for instance that the Diesels burned crude oil instead of kero-
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