What's inside those mechanized fighting vehicles?
See the insides of rifles, handguns, automatic weapons, etc.

A gorgeous noir-like cutaway of an atomic pile by Alexander Leydenfrost.  But why does the drawing look so vague and devoid of details?

Partially, that was the Leydenfrost style.  His Brooklyn-Battery Tunnel cutaway drawing shows that he emphasized moody shadows and light over the cool and the technical.

But mainly, at the time of this illustration, atomic production was still a closely guarded secret.  So Leydenfront had to imagine what a pile must look like based on scant information from The Smyth Report.

Published in July 1945, the Smyth Report, officially known as The Official Report on the Development of the Atomic Bomb Under the Auspices of the United States Government, provided a technical, though generalized, overview of the production of nuclear weapons.

Click to Enlarge to 1609 x 766 px:

Atomic Pile Cutaway 1950

Atomic Pile Cutaway 1950

Source:  LIFE February 27, 1950

The Brooklyn-Battery Tunnel was new in 1950, when Alexander Leydenfrost drew this cutaway.  At 9,117 feet, it is the longest continuous underwater tunnel in North America, according to Wikipedia.

Click to Enlarge to 818 x 771 px:

Brooklyn Battery Tunnel 1950

Brooklyn Battery Tunnel 1950

Source:  Popular Mechanics May 1950