Changing ENIAC's vacuum tubes, c. 1940s.

Fullsize image: https://s3-us-west-1.amazonaws.com/h...e_fullsize.jpg



Previously:

Bombe code-breaking machine - GIF
Babbage difference engine - photo
4.5 megabytes of data represented by punch cards - photo
Z1 mechanical computer replica - photo
Cray-1 supercomputer - photo