ScientificAmerican1894-07-21.jpg Ivory Soap -1910AThumbnailsScientific American 1897-10-23Ivory Soap -1910AThumbnailsScientific American 1897-10-23Ivory Soap -1910AThumbnailsScientific American 1897-10-23Ivory Soap -1910AThumbnailsScientific American 1897-10-23Ivory Soap -1910AThumbnailsScientific American 1897-10-23
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