The Seth Thomas Grade 291: 18-Size, Model 5, Two-Tone, 21 Jewels – Reclassified From Research Grade 280

The lack of factory records for Seth Thomas has been a challenge for researchers and collectors alike. Fortunately, serial lookup engines have been created using observations from surviving watches, allowing some insight into the watch production for this company.

Proper grade classifications have been another hurdle in properly identifying Seth Thomas watches. While most grades can be found with descriptions in original advertising and trade materials, several recorded movements do not have logical matches. This has puzzled collectors and forced researchers to fabricate “researcher-assigned” grades for these particular movements.

Recently, a new factory grade classification finally unsurfaced in the c.1911 N. Gamse catalog. The researcher-assigned “Grade 280” can now properly be replaced with the factory Grade 291.

The N. Gamse catalog describes the No. 291 as:

18 SIZE, 21 Jewels, No. 291 Seth Thomas.
No. 291, 18 size, 21 jewels, special, gilt, nickel, Damaskeened, Breg. Hair-Spring, patented regulator, adjusted, double-depressed dial. $12.90c.1911 N. Gamse Illustrated Catalogue

The catalog also includes an illustrated cut of the movement, removing any doubt as to the appearance of the Grade 291, exactly matching the researcher-assigned Grade 280. Below is a surviving example of the Seth Thomas Grade 291 that was auctioned by Jones & Horan in October 2019 as a Grade 280.

The mention of “special” in the grade description also indicates the Seth Thomas No. 291 may have been a watch sold exclusively by N. Gamse, explaining why no other standard advertisements or references in grade lists has been discovered.