Old communications encryption equipment;

http://jproc.ca/crypto/kg14.html

http://en.wikipedia.org/wiki/KW-26

http://jproc.ca/crypto/kl47.html

http://www.cryptomuseum.com/crypto/usa/kw7/ 

How to send photos (1937) Watch this video to see explained the latest technology in 1937:

               http://www.youtube.com/watch?v=LRTlm_cKZ8Y&feature=em-uploademail