Source of Turing-machine illustration
The figure appears to come from the paper "Games, Logic, and Computers" by Hao Wang, which appeared in Scientific American, Volume 213, Number 5, November 1965, pages 98-106.  There is a copy online here:

http://www.cs.virginia.edu/cs200/readings/wang.pdf

In case you're wondering how I found it, I googled 'Turing machine "memory dial"'.  None of my Turing machines have a memory dial, so I was hoping to learn where to buy one.