Welcome, the Old Town canoe with hull identification number XTC91939M74I and serial number 191939 is an 18 foot long Chipewyan model that weighed 76 pounds. It was built in November, 1972. The original exterior color was yellow. It shipped on May 6th, 1974 to Minneapolis, Minnesota. The back side of this scan shows that it was soft in the stern end. Scans of both sides of this build record can be found by following the links at the attached thumbnail images below.
These scans 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 contribute, 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. The Tripper model is made of the same material but the length is 17 feet, 2 inches long and it is a few inches deeper than this canoe. Feel free to reply here if you have any other questions.