Copper foil with etched perforations at 20,000 holes to the square inch
Nuclear Physics
1942-1943
Copper foil with etched perforations at 20,000 holes to the square inch, by Sun Engraving Co., Watford, Hertfordshire, England, 1942-1943. Object was constructed for the Tube Alloys Project for experiments on the separation of uranium isotopes, 1942-1943.