Styles and Design
Cases with pillars and scrolling echoed the popular French-style mantel clock. Resembling an S-curve in profile, simpler Ogee cases were also featured. Rectangular mantel clocks (measuring approximately 26 by15 1/2 by 4 1/2 inches) had the clock face at the top and a decorated glass panel at the bottom. On the dial were two small winding holes and dotted minute marks surrounded by one or two lines, two on earlier models.
Construction Materials
The clocks utilized wood for movement and case until brass movements replaced wood in 1842. Dials were ceramic or metal and often decorated. For casings, Thomas used etched or painted paned or beveled glass, as well as enameled iron and enameled, veneered and gilded wood. The company also used an exclusive celluloid veneer called adamantine to simulate marble, wood and onyx.
Marks and Labels
The trademark initials "S" and "T," written in either Old English or plain upper-case letters, sit within a diamond, surrounded by a circle. The Seth Thomas name or logo is imprinted on metal inside or printed on the dial. In addition, paper labels and stamped dates can be located on the bottom or back of the clock.