Above, you will find the Ehrhardt American (EA) Numbered Drawings for each of the twenty-four Seth Thomas pocket watch models that he identified. The Ehrhard American (EA) Numbered Drawings record the shape and penetration points of the movements’ top plates.  The movements are described in great detail for us by Roy Ehrhardt in his “Identification and Price Guide to American Pocket Watches”.  He devised this system using numbered diagrams, drawings of every American made pocket watch manufactured before 1999. This system covers every pocket watch produced by any manufacturer in the United States. The specific EA numbers for Seth Thomas movements range from EA 805 - EA 823. The only difference in nomenclature that you will see between what is used in Roy Ehrhardt’s EA Numbered Drawing system and what is used by the Seth Thomas Fan Space is in naming the 24th model, which was never named by the Seth Thomas Watch Company, “Pendant Model 24” instead of “Model 26”. I believe that Mr. Ehrhardt used the “Model 26” nomenclature because the Seth Thomas Watch Company alternately advertised their 6-size Centennial model as a 6-size movement, a 4-sized movement, and a compact 12-size movement, which would have required a 6-size Model 24, and 12-size Model 25, and a 4-size Model 26.  In fact, the 12-size Model 25 was really a 12X6-size Model 24, and the 4-size Model 26 was really a 6-size Model 24 with a special snug dial, snug hands, and a snug case.

Another component of Roy Ehrhardt’s Identification and Price Guide to American Pocket Watches that is most correctly associated with the use of EA diagrams to identify the manufacturer of an unknown pocket watch is the “Alphabetical Listings”.  If an unknown pocket watch has a trade name or private label signature on the dial or on the movement; the actual manufacturer can be easily identified using the Alphabetical Listings. Once a name is found in the Alphabetical Listings there is coded information provided that describes the movement’s features in detail. A good example to consider would be the name Lakeside. There are six Lakeside listings to examine and disambiguate for a proper identification. See the listing below:

In the first listing: Lakeside (Chas. Wendel, Chicago) (Ca 1882)

(18S-11J-HN2L-U-”31”) (EA 332)... $35-55

Lakeside is marked on the movement - The movement was produced for Chas. Wendel of Chicago circa 1882

The 18S indicates that the movement is 18-size and the 11J indicates that it has 11 jewels. The H indicates that it is hunting orientation. The N indicates that it has a nickel finish. The 2 indicates that it is a Model 2. The L indicates that it was lever set. The U indicates that it is unadjusted. The “31” indicates that the grade is 31. EA 332 refers to the Numbered Drawing 332. By looking at that numbered drawing you can see that the movement was manufactured by Hampden Watch Company. $35-55 indicates that the 1999 value range of the movement in pristine condition is 35 U.S. dollars to 55 U.S. dollars.

The highlighted listing: Lakeside-Chicago, Ill.-15 Jewels-(Montgomery Ward) (Ca 1905)

                                                                           (18S-15J-OJ8L-U-”36”) (EA 811) (77-92)..$60-80

Lakeside - Chicago, Ill is marked on the 15-jewel movement - The movement was produced for Montgomery Ward circa 1905

The 18S indicates that the movement is 18-size and the 17J indicates that it has 17 jewels. The O indicates that it is open-face orientation. The N indicates that it has a nickel finish. The 8 indicates that it is a Model 8. The L indicates that it was lever set. The U indicates that it is unadjusted. The “36” indicates that the grade is 36. EA 811 refers to the Numbered Drawing 811. By looking at that numbered drawing you can see that the movement was manufactured by Seth Thomas Watch Company. $60-80 indicates that the 1999 value range of the movement in pristine condition is 60 U.S. dollars to 80 U.S. dollars.

If there are no markings on the movement or the dial; it is still a relatively easy process to browse through the EA Numbered Drawings.  I usually start the initial process by partially defining the movement in terms of 1. orientation, hunting or open-face; 2. type of top plate, full, 3/4, bridge; and 3. any external wheels or other features on top of the plate. Orientation is as indicated by the position of the balance bridge.  If it points counterclockwise; it is open-face.  If it points clockwise; it is hunting. Having a few initial reference points greatly enhances your ability to scan through the Numbered Drawings quickly.

Ehrhardt American (EA) Numbered Drawings

for

Seth Thomas Pocket Watches.