The Rotary Seconds Dial

The rotary seconds dial, the wondering second, the secometer, modern seconds indicator and the jump second are just a few of the names associated with a unique seconds display used in wrist and pocket watches. 

My 1930 Illinois Guardsman with the rotary seconds dial
This is a first for me as I picked up an Illinois "Guardsman" that features a rotary disc that displays the seconds where traditionally you would see a hand; either a sweep seconds hand or a seconds hand positioned at the 6 (or 9 like a number of my other Illinois watches).

Close up of rotory dial on my Guardsman
If you look closely above you can see a dark spot on the "6". That is the pivot from the middle of the seconds disc and it protrudes through the dial. Below you can see the centre of the disc and the raised pivot that goes through the 6 of the dial.

Close up of the Guardsman seconds disc on the watch movment


1930 ad showing the Guardsman bottom middle with its "seconds indicator"

Illinois, Waltham, Bulova, Hamilton and other makers have incorporated this novel way of displaying the seconds. Some with better success than others. I equate the success with the ease with which you can read the seconds. For my Guardsman above, you can easilty read it. On the other hand Waltham's rotorary second on its wristwatch models featuring it were pretty small to see but their pocket watches below were quite readable.

Walthams "Modern Seconds Indicator" pocket watch version ad

Hamilton's 1930 secometer for their pocket watches

The seconds disc did not seem to find a permanent home in watch manufacturing and seems to have disappeared in the pocket and wrist watch in the 30's. I may have found another watch niche for me to collect!