In 1905 he co-invented the first metallic alloy from which a high-resistance wire could be made that could be used as a durable and safe heating element.
While working with an electric storage battery and doing technical writing, he experimented with nickel and chromium alloys in his spare time.
In 1904, needing a better location to work on his wiring project and additional funding, he made a business arrangement with William Hoskins of Chicago.
He hired Marsh at a small salary – while giving him permission to work on the alloy project in his spare time.
This aluminum found a wide range of applications, from the aviation industry to electrical cables and packaging materials.
[4] Toasters, dental furnaces[clarification needed] and chromel wire for home appliance manufacturers were the first focus of the Hoskins company.
In 1941, the American Metals Congress bestowed upon Marsh with The Sauveur Award for outstanding metallurgical achievement.