ing so thin that one can
make out figures silhouetted on the opposite side of the hull when it
faces the light.

The Tempelhof factory, with Mr. Trenkmann as Manager, now includes many
buildings and workshops, several put up recently for dyeing and treating
fabrics. During the war a thousand persons were employed. The gas bags
used in all the German airships were made there; and the factory working
with another firm under a patent license agreement, made a majority of
the German observation balloons.

The Maag-Zeppelin Gear Works

It was not long after the war started that Count Zeppelin had difficulty
in securing delivery of cog-wheels, etc. In 1915 he co-operated with Mr.
Maag, a Swiss engineer, in starting the Friedrichshafen Cog-wheel and
Gear Factory (Zahnradfabrik Friedrichshafen G.M.B.H.), another
subsidiary (Plate 18.). The plant is as modern as they could make it.
The buildings occupy three acres. They include office buildings,
workshops for hobbing, heat-treating, grinding and polishing cog-wheels
and the complete gear transmissions. Aluminum castings are obtained from
the foundry of the parent company, Luftschiffbau-Zeppelin.

The gear works is equipped throughout with automatic machines built on
the Maag patents. His cog-wheel involves a new principle, giving utmost
safety and freedom from wear and noise. Specially designed testing
machines are used, guaranteeing precision of the gear wheels.

[PLATE 37: "DELAG" Zeppelin Route Chart, 1912-13.]

During the war the company made all the gearing on the Zeppelins and
airplanes. The factory is now operating at full capacity, employing 500
men, making motor car gears, transmissions, etc. The manager is Dipl.
Ing. Count von Soden.

The Hangar Construction Company

Back in 1913 a subsidiary was founded, first as a consulting engineering
concern; but soon thereafter it became the Zeppelin Hangar Construction
Company (Zeppelin Hallenbau G.M.B.H.). Through long practical experience
it is prepared to build and equip complete airship harbors and dock
yards, prepare landing fields and airdromes. One of the principal
developments with which it has been accredited is the rotary shed,
single or double. It has erected special workshops, gas plants and all
the accessories of a modern flying terminal.

The company designed and constructed the two modern sheds at
Friedrichshafen, the entire Staaken plant, the "DELAG" airship harbors
and nearly all the other air