The Old Century line was the cheapest design that the company offered and there is some evidence that these models were on the drawing board from the very beginning. The Model 10 was open-face and the Model 11 was hunter, and very little effort was made to dress up these 7-jewel gilt or nickel movements, which had stamped parts and flat hairsprings. They were to be a workingman's piece, retailing for $1.90 in the 1904 catalog. None were marked Seth Thomas; all of the factory's output in the Century Series were made up entirely of named grades.
The first printed record of the Century model was the 1904 catalog, in which all thirteen of the company's 18-size models were listed, even though some of them had already been discontinued. Both of the Century models were listed in that catalog for replacement parts, but the specific year that Seth Thomas's lowest-grade 18-size watch was introduced is not known, why the factory dropped the Old Century line, or when.
Totals for the Old Century models are not known, but it's doubtful that more than 100,000 were made.
To date, the only two known named grades in the Models 10 and 11 are the Century, for which the models were named, and the Pan-American, after the world's fair exposition held in Buffalo, NY in 1901, where President William McKinley was assassinated. All of the Models 10 and 11 movements turned out by the factory were named grades with matching dials; none were marked Seth Thomas on the dial or the plates, and none of them had serial numbers. There were roughly fifty named grades in total, but only these two were used exclusively on the Old Century Series, even though the New Century line would eventually add a dozen more, including Athabasca, Criterion, Liberty, Republic, Stratford, and Wyoming, and others.
7-jewel nickel Model 10/11
7-jewel gilt or nickel Model 10/11