NASA electric discharge machine, c. 1967. Full caption: "ELECTRIC DISCHARGE MACHINES WITH TURBINE BLADE AND ROCKET ENGINE AT THE TECHNICAL SERVICES BUILDING TSB"
Fullsize image: https://s3-us-west-1.amazonaws.com/h...e_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...dm_machine.jpg
Previously:
https://www.homemadetools.net/forum/...984#post168114
https://www.homemadetools.net/forum/...751#post163513
https://www.homemadetools.net/forum/...565#post178097
https://www.homemadetools.net/forum/...395#post177425
https://www.homemadetools.net/forum/...281#post177015