About the Seth Thomas “Mark I” Clock
The Seth Thomas “Mark I” Boat Clock, produced around 1941, is a noteworthy addition to any collector’s inventory. This model, identified by the Mark I designation, features a compact black bakelite case, measuring approximately 6 inches (15 cm) in width, with a dial diameter of 3 inches. The clock, specifically unit number 13929, is distinguished by its naval origins, as evidenced by the removable wall mount that was once secured to a boat. Despite its history, the clock remains in running order and functions well as a desk clock after being removed from service. While the exact rarity of this model is not specified, it holds significance due to its unique combination of design and historical context.
Auction Records and Price History
The following 1 auction record(s) show actual sale prices for the Seth Thomas “Mark I” model clock. Prices vary based on condition, originality, and current market demand. Search for more records on AntiqueClocksPriceGuide.com.

C.1941, (dated), Seth Thomas, Mark I Boat Clock in a black bakelite case, less rear mount.
Condition: obviously removed from Naval service at some time, the person simply pulled the hinge pin and left the wall mount on the boat. Still works fine as a desk clock. Unit with serial number 13929, and is in running order. Dial = 3″, overall width = 6″ [15cm]
Sold: $125 | Date: 4/22/2007 | Source: R. O. Schmitt Fine Arts