JF Ptak Science Books
This is the bible of the Reeves Instrument Company's great REAC--the Reeves Electronic Analog Computer. It is a handbook of maintenance instructions and operations, published in 1951, and is chock-a-block with what seems to be any techspecs and data that you'd need to operate the machine. It is two inches thick and has multiple fold-out schematics.
The following appeared in The American Mathematical Monthly, vol 60, #4, "The NOTS REAC", pp 237-243.
Rare. Not foulnd in WorldCat/OCLC. $500