Emergency lighting circuits were picked up by cutting out all general lighting circuits and then marking all remaining lights with a blue stripe. These circuits were then cut down to bring them to a safe carrying capacity of a 110 volt, 140 ampere storage battery, which was installed for additional safety in case of accident. These latter circuits were so arranged that if for any reason the main supply should fail a solenoid would automatically cut them in on the storage battery. VENTILATION The next problem was the ventilation of the ship. There are 113 ventilating blowers (51 exhaust and 62 supply) and after all blowers were located the problem that remained was to locate the compartment they ventilated. No plans were available. This system was traced out by starting a blower and then tracing up the ducts and recording the particular section that it ventilated. INTERIOR COMMUNICATION All interior communication was traced out in the same manner, _i. e._, start from the transmitting apparatus and from there on trace the piping and wiring until finally we arrived at the receiving end. Then there were two Anshutz Gyro compasses, which no one knew anything about, but here, again, through the close co-operation of the Navy Yard force and the ship’s electrical force, the secret of operating these compasses was successfully solved. To sum up the whole, one may say, it was the dogged determination of the electrical forces, both civilian and enlisted, who never gave in to any proposition that came before them, that carried everything through to a successful issue. _Steering Engine Data_ E. P. H. The control and manœuvering of a large ship such as the _Leviathan_ is a responsible job. This vessel’s steering arrangement, or steering gear, is of steam engine type, connected to a hydraulic telemotor. The gear is so easily manipulated that a small boy standing on the bridge of this great ship can control any course or given route that is desired to be taken.