I have this Indian Motorcycle wrench with an M cast mark. Other examples of these Indian wrenches have no marks and have 1 or 2 very minor style differences. But I am focusing on the "M" version. Who is "M"???
I found a posting on Worthpoint that shows a Ford adjustable with a similar mark, claiming to be by Manzel Forging Company, Buffalo, NY. "Briefly Noted"in Alloy Artifacts as a Ford wrench maker.
There are similarites in these two wrench photos - but the smaller Indian wrench has a bit of curve in the handle.
Indian 7" adjustable and Ford (approximately 8 to 9").