This is a question for Jerry Treiman. Waltham #20166241, 19J. It is in an octagon 14K case by Depollier, with a hinged back and a snap on bezel.
I don't know if this is a 12 or 14 size watch. I am guessing 14S. Anyhow, who was Depollier, and when and where did he work?

Depollier was a New York jeweler and case-maker. There are quite a few posts on this Board, including some from Jerry Treiman, discussing Depollier. You will find them easily by running a search.

Hi Jerry -- although the serial number list does not specify the size of this run, it is a 14-size Colonial A. This thin-model watch was made in 14 and 10 size, but the first 10-size was in the 22-millions. I think they forgot to include the size because there was only the one size when yours was made. The attached picture compares the two sizes. The most readily identifiable differences are the much larger gap between the crown wheel and plate edge on the 14-size and also the way the barrel bridge comes to a sharper point to the right of the grade name on the 10-size.

Jacque Depollier was a maker of high-quality gold and platinum cases. He made a lot of cases for the factory-cased Colonial A, opera watch and many smaller ladies watches by Waltham. I am not sure when the association began, but by the early 1900s Depollier was also involved with the Dubois Watch Case Co. of Brooklyn, NY. Very fine Dubois cases are identified by the four "D"s in a flower pattern.

Jerry - octagon cases are not too common on the Colonial A. Can you post some pictures?

Jerry: Unless someone makes me an offer I can't refuse, you will see this one in Pasadena. but here are two images.

Back.

Jerry Treiman;
I always get confused about this, so if I am wrong, please correct me. My understanding is that a Colonial A Riverside movement is 10-size or 14-size and that Colonial B is 12-size. The Colonial marking was to indicate a more slender movement than the standard model 1894 (referring to the movements in your photograph). Were, however, all Colonial models marked Colonial? The "B", I am aware, was not always used, but given the model size restriction, that is understandable. I guess that my question boils down to asking just how thin is thin? Should a dress model Riverside 1894 movement be regarded as a Colonial movement even though it is not marked Colonial? Thanks!

Let's start at the beginning.

The first Waltham to have the Colonial label was the "Colonial Series". This movement was based completely on the 1894-model 12-size and uses almost entirely the same parts. It is the same thickness as a standard 12-size watch and the back (or top) plates are the same size and layout. The pillar plate is 14-size and the watch takes a larger dial although the foot positions and centers are the same as the standard 12 size. It is the larger dial that makes this watch seem relatively thinner. A standard 12-size would never be considered a Colonial.

The next Colonial is the Colonial A, 14-size. This is a distinctly thinner movement.
The 10-size Colonial A was next, using the same wheels and parts but the dial is different from the 14-size -- smaller, with different centers and dial feet.

The Colonial B is usually listed as the 1924 Colonial and is 12-size in diameter but thinner than the standard 12-size (although not as thin as the Colonial A). I don't think these movements were marked Colonial except on a few of the later production models, but never with the "B". The dial is not interchangeable with any of the other models.

Jerry,
Thank you very much. The pillar plate and dial combination explain a great deal and also why they are not interchangeable. The involvement of the 1924 movement is the key - I think. If I understand correctly, although the 12-size 1894 mechanism was used in the production of the 14-size Colonial, there is no 12-size cased 1894 Colonial. The 12-size cased Colonial is a model 1924.