One of the accessory companies founded by Zeppelin in 1909 was the Maybach Motor Factory (Maybach-Motorenbau) (Plate 18), at Friedrichshafen. It was enlarged considerably during the war, supplying practically all the airship motors used. Today the Maybach works include three large three story factory buildings, parts of which are devoted to executive offices, two workshops of recent origin occupying two acres, many engine testing stands, laboratory, and a power plant fully equipped with the latest machinery. The entire plant is under the management of Mr. Maybach, inventor of the only motor designed for airships alone. One reason for the peculiar efficiency of the plant is the special workman’s training department which has received considerable attention from the executives. [PLATE 34: “DELAG”-Zeppelin Harbor at Frankfort a.M., 1912. “DELAG”-Zeppelin Harbor at Baden-Baden, 1910.] The first Maybach motors were produced in 1912 (Plate 19), and were 140 and 180 horsepower. They contributed largely to the success of the commercial Zeppelin before the war. In 1915 a 240 horsepower motor was built, and this was the principal motor used on the military and naval Zeppelins. Maybach produced an entirely new motor in 1917. It supplied from 260 to 320 horsepower and is noted as the first supercompression motor. Quickly recognized as the best engine for airplanes, it became the leading German aviation motor until late in 1918 when other motors built on similar principles appeared and were found more adaptable to the planes. Maybach, meanwhile, developed other types (Plate 20), principally 160 and 260 horsepower units for heavier-than-air craft. The following table illustrates the development in types and performance of engines: Performance of Engines—1892-1918