To insure greater safety, the fuel supply was divided among sixteen tanks, all of which were interconnected with each other and the engines so that gasoline from any tank or tanks could be diverted to any particular engine. The supply of lubricating oil for each engine was carried in a tank in the gondola itself. _Control._ Vertical and horizontal stabilizing surfaces of conventional form were built on the sharply tapering rear end of the frame, the elevator and rudder being similar to those used in aeroplane construction, except that the rudder was in two sections, the larger of which was placed on top of the envelope. The control of these surfaces, the operation of all the engines, the control of the water ballast, the air supply to the balloonets, and the fuel supply to the motors were all concentrated at a panel board in the commander’s cabin, the forward end of which bore a close resemblance to the bridge of a man-of-war. By means of thirty-eight push buttons, half red and half white, air could be released from or pumped into the balloonets, while in a similar manner the contents of any one of the water-ballast tanks could be emptied. Elaborate controls were provided for the power plant, it being possible to vary the speed or stop any one or more of the motors from the bridge. The rudder and elevators were operated by means of small hand wheels, similar to a marine steering wheel. One of the most prominent features of the operating cabin was a huge chart frame, capable of carrying a large scale map covering a considerable area, as well as an ample supply of maps. Few instruments were found in the captured ship and it is thought highly probable that everything not fastened in place had been dumped overboard at the last to increase its lifting power. [Illustration: Fig. 24. One of Six Gondolas, or Power Units of the Zeppelin L-49 _Copyright by Underwood and Underwood, New York_] Apart from the use of standardized fittings and parts and the employment of a great deal more power in a slightly different manner than had characterized the earlier types of Zeppelins, the L-49 revealed nothing of unusual importance in airship design and certainly none of the world-beating features that German propaganda had been heralding for some time previous.