Thompson Brothers Boat Manufacturing Co.

Serial Number Format - Usually no serial number present. There has been no pattern established for those that do have a serial number.

Dating Thompsons - So far, no good way to date Thompsons has been discovered. One possibility that has been suggested is that earlier canoes have a brass nameplate fastened to the deck, and that '50's era boats have a chromed nameplate. So far my own observations seem to support this theory, but it is still up in the air, as they say...

The following table was put together by Dave Osborne, who culled the information from the Thompson Bros. Catalog CDROM for the Hiawatha model. While using it to date canoes might require the assumption that different woods weren't substituted, it can serve to help narrow down when your Hiawatha may have been built.

Hiawatha Materials Matrix by Dave Osborne
Year	Thwarts	Seats	Gunwales
1921-1923	White Oak	White Oak	Spruce
1924-1928	Selected Maple	Selected Maple	Spruce
1929-1937	White Maple	White Maple	Spruce
1939-1941	White Maple	White Maple	Mahogany
1942-1943	Mahogany	White Oak	Mahogany
In 1921, the Hiawatha was only offered in 16' and 17' lengths. 30" decks made of cedar or mahogany were offered in all years. Catalog image shown in 1941 and later show narrower style half-ribs. (rumor has it the half rib style changed in 1938).

Deck Profile - Usually as above. Decks with a shallow single-lobe are also known (see photo below), as are long decks.

Deck Strap - The presence of a metal strap beneath the deck, spanning between the inwales, is usually a characteristic of Thompsons. See photo below.

Gunwale-Stem Junction - The inwales terminate on the inboard face of the stem, and the endgrain of the stem is exposed. The outwales carry along the sides of the stem (and outer stem if present).

Planking Pattern - Thompsons have a very distinctive planking and goring pattern; when the canoe sits upright, the planking appears to run in a straight line parallel to the keel, unlike others such as Old Town that turn upwards at the stems. See photos below.

MODELS OFFERED
Model	Years	LxWxD	Stem Profile	Half Ribs	Notes
Hiawatha	1921-1946	16 x 33 x 13 17 x 34 x 13 18 x 34 x 13	Long-Nose	Yes
Indian	1907-1927	15 x 32 x 12 16 x 33 x 12½ 17 x 33 x 12½ 18 x 34 x 12½	Traditional	No
Indian	1928-ca.1950	15 x 32 x 12½ 16 x 33 x 12½ 17 x 33 x 12 ½ 18 x 34 x 12½	Long-Nose	No
Indian	ca.1950-1959	16 x 35 x 12	Traditional	Optional	Same as 1937-50 Ranger ?
Voyageur	1910-ca.1914	15 x 32 x 12 16 x 33 x 12½ 17 x 33 x 12½ 18 x 34 x 12½	Traditional		Built on same mold as Indian of same era.
Ranger	1937-ca.1950	15 x 35 x 12 16 x 35 x 12½	Traditional	Optional	Similar to 1907-28 Indian
Ranger	ca.1950-1959	15 x 35 x 12 16 x 35 x 12½ 17 x 35 x 12½	Traditional	Optional	Flat Sheer
Agawam	ca.1922	16 x 36 x 13			Like Indian
Canadian	ca. 1907	15 x 32 x 12 16 x 32 x 12 17 x 32 x 12	Traditional		Low sheer
Hudson Bay Canoe	ca. 1936	16 x 35 x 13	Extreme at Ends	Yes
Camp Canoe	1936-ca.1939	16 x 33 x 12¾ 17 x 34 x 12¾	Long Nose		3" Tumblehome

Notes:

Stem Profile:
Traditional refers to the common, sweepingly recurved stems found on most wood canoes, such as the Old Town Otca.

Long-Nose (alsoknown as shovel-nose or sturgeon-nose) has its curve concentrated low down on its stem. This stem profile is also seen on many Ojibway bark canoes and the Old Town Molitor.

Half-Ribs:
Present, absent, or optional as noted. There is always the possibility that half-ribs were installed in Indian model canoes, but I haven't seen reference to them in the catalogs (yet).

Dates: Subject to revision.

Changing Models:
Earliest Ranger and latest Indian both similar to earliest Indian, but note different given dimensions. Still, could have been built on the same form.

Early Ranger same as latest Indian - probably used same form just changing the name. Latest Ranger probably built on same form as early Ranger and latest Indian, but with a different sheerline.

Thompson Decks

Typical Thompson deck profile. Underside of deck has a reverse ogee (cyma reversa) moulding profile	Deck removed showing strap found beneath deck.

Different deck style occasionally seen on Thompsons.	Yet another variation of the Thompson deck cut-out.

Thomspon Planking


Thompson planking appears to run parallel to the keel.