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Scientific American 1894-07-21

ScientificAmerican1894-07-21.jpg Sanatogen Food Tonic -1910BThumbnailsScientific American 1912-11-02Sanatogen Food Tonic -1910BThumbnailsScientific American 1912-11-02Sanatogen Food Tonic -1910BThumbnailsScientific American 1912-11-02Sanatogen Food Tonic -1910BThumbnailsScientific American 1912-11-02Sanatogen Food Tonic -1910BThumbnailsScientific American 1912-11-02

Hardening composite plates for bank vaults by immersion in the Hudson River. hardening to make burglar-proof vaults.



Source: Steve Kirch, collector, and creator of a great website about SCIENTIFIC AMERICAN in the past

Restoration by: magscanner