Welcome, the Old Town canoe with serial number 152630 is a 16 foot long, CS (common sense or middle) grade, HW (heavy water) model with red Western cedar planking, open spruce gunwales, and a keel. It was built between March and June, 1949. The original exterior paint color was dark green. It shipped on June 17th, 1949 to Mahopac, New York. A scan showing this build record can be found below.
It is also possible that you could have another number or manufacturer if this description doesn't match the canoe. If you really have an 18 foot canoe then please attach some pictures of the serial numbers from both ends (or indicate which digit is the least clear). Some of the suggestions at https://www.wcha.org/forums/index.php?threads/791/ may also help. Feel free to reply here if you have any other questions.