elin Harbor at Hamburg, 1912.

"DELAG"-Zeppelin Harbor at Leipzig, 1913.

"Sachsen" landing for first time after completion of harbor
June 1913.]

The Zeppelin-Maybach Gearless Car

In the fall of 1921 Maybach exhibited for the first time the 22-70
horsepower gearless motor car, designed to simplify operation. Only what
is termed the direct speed is used in driving; except for grades of more
than 10%, and for the starting on these grades, when apart from the rest
of the mechanism a single gear is used by pushing down a pedal. When it
is released, the direct grip is automatically restored without noise or
vibration. Backing is accomplished with the electric starting motor by
means of a pedal. Smaller cars of this type are now under construction.

New Methods of Gas Bag Fabrication

The early gas bags for the Zeppelins were made of rubberized cotton
fabric. This material was comparatively heavy and further, it allowed
the hydrogen gas to deteriorate during prolonged operations. Count
Zeppelin experimented with various materials, particularly goldbeater
skins, which are the big intestines of oxen and other cattle, treated
until they become like leather and then they are very thin, tough and so
durable that they wear much longer than fabric. Zeppelin learned that
goldbeater's skins held gas better, also, and unlike rubberized fabric,
practically eliminated the danger of electrical sparks due to friction
or tearing.

He organized the Gasbag Manufacturing Company (Ballon-Huellen G.M.B.H.)
at Tempelhof in 1912, to carry out this development and goldbeater's
skins were used exclusively, as the loss of two Zeppelins that year was
traced directly to the balloon fabric in the gas bags causing sparks
which exploded the hydrogen. The ships were the LZ-12 and the Schwaben,
the former exploding during inflation and the latter while moored at
Dusseldorf.

[PLATE 36: "DELAG"--Zeppelin Harbors at Liegnitz and Dresden,
1913-14.

"DELAG"--Zeppelin Harbor and Manufacturing Plant at Potsdam
(near Berlin), 1915.]

The goldbeater skins possessed certain disadvantages, however. For one
thing, they were difficult to handle because of their small size; so
they were shingled on to thin cotton fabric. Since 1917 silk has been
used, the combination when prepared being so light and thin as to be
transparent. In fact, the Zeppelins hulls are themselves nearly
transparent, the fabric envelope and gas bags be