Old Town 178941 is a 17 foot Otca with 20 inch decks and coaming, fitted with a keel and originally painted dark green. Looks like it was dacron covered rather than canvassed-- not sure if I made that out right, but the build record is attached. This canoe was shipped 10/9/1967 to the Boy Scouts of America in Winter Haven, Florida. Not exactly a thirties boat, but in the 60s it was no longer standard for the Otca to have these longer decks with coaming, so perhaps someone was determining age by the canoe's appearance.
This may still not be your canoe. I checked 7894 and found it to be a 16 foot CS grade HW shipped in 1908... and Carleton 7894 is a 19 footer with mahogany long decks, shipped in 1910.
Scans of these records were made using the considerable skills, time, and money of WCHA members, and any contributions to support this and other WCHA projects are greatly appreciated. If you're already a WCHA member, I tip my WCHA logo cap and hope to see you at assembly, with or without this canoe!
Kathy