There is a 1937 NEC book on ebay that has sparked some interest...it is bid up to 91 dollars as or this post

item #6948950311

Anything special about the 1937 NEC?

shortcircuit

sold for 127.50...any of you old timers need some extra retirement cash

shortcircuit

My old NEC books are starting to look like better investments than my Disney stock.

Wow! I wonder what I'd get for some of my old radio handbooks?

I have a "Manual of Modern Radio" dated 1933 which I remember finding in a second-hand bookshop in London about 1977. Don't want to part with it, but it would be interesting to see what somebody would be willing to pay.