Welcome and congratulations, the Old Town canoe with serial number 67680 is an 18 foot long, CS (common sense or middle) grade, HW (Heavy Water) model with red western cedar planking, open spruce gunwales, ash decks, ash thwarts, ash seats, a keel, outside stems, a floor rack, and sponsons. It was built between June and July, 1922. The original exterior paint color was dark green. It shipped on August 8th, 1922 to Kalamazoo, Michigan. A scan of this build record can be found by following the link at the attached thumbnail image below.
This scan and several hundred thousand more were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others. A description of the project to preserve these records is available at
http://www.wcha.org/catalogs/old-town/records/ if you want more details. I hope that you will donate, join or renew your membership to the WCHA so that services like this can continue. See
http://www.wcha.org/about-wcha to learn more about the WCHA and
http://www.wcha.org/store/membership to join.
It is also possible that you could have another number or manufacturer if this description doesn't match your canoe. Canoes with a family connection are always extra special. Feel free to reply here if you have any other questions.
Benson