The Hindenburg's Gondola Under Construction (1936)

Unlike balloons, zeppelins have a rigid skeleton, generally of aluminum, that makes them a sturdy lighter-than-air craft.

 

(Note: An inexpensive viewer can turn the side-by-side images on the computer screen into a 3-D image. The viewer is available for $4.95 from the following source:

 

civilwarin3d.com/html/viewers.html )

 

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