This is a heckuva story although most of it occurs after 1939. Click on the link to learn more.
“Chestien Wynn, a 70 year old retired attorney with an interest in lubrication chemistry, discovered a formula he named ‘Wynn’s Friction Proofing’ Oil. This surface treatment for metal actually changed the chemistry of the metal, making it softer and better able to withstand friction and wear.
“Chestien Wynn would mix a batch of his product in his one car garage workshop, fill and label glass bottles with it and sell them to the local service stations and garages. Motorists, who used the products once, wanted another bottle of it.”
“While some thrifty growers still burned stacks of old tires, the majority turned to the coke burning units (‘smudge pots’) as they became available and later invested in the more efficient oil-fueled heaters. All methods of orchard heating are costly, not only in the price of the fuel consumed, but in the wages paid the manpower required for the operation and maintenance of the system. I recall that as a general figure it was estimated that fuel oil costs accumulated at a minimum of $50 per hour (1939 dollars!) for every ten acres heated.” — G. Carrol Rice
Plomb was a major tool manufacturer founded in Los Angeles. It was the predecessor of Proto Tools. As the company expanded and acquired factories elsewhere, they changed the location name on their tools in 1939.
Early 1939 – “9” followed by a letter. The “O” in Plomb was represented by an upside down triangle, and the tools in Early 1939 were stamped Los Angeles.
Late 1939 – “9” followed by a letter. The “O” in Plomb was represented by an upside down triangle, and the tools in Late 1939 were stamped “Made in U.S.A.”