Can someone help me identify this early pocket watch chronograph caliber?

Modest_Proposal

Needless to say, you have a very special watch. I especially love the curve-y chrono seconds hand. The movement seems to be a higher grade variant, with more jewels than usually see in these and the snail regulator.

I believe this is a caliber 19 CH, which I read came into the market is 1889.

I quote from one of the websites below: "The chronograph based on the LUGRIN patent was probably the first chronograph by LONGINES and was launched in 1878. This caliber 20 H can be found with serial numbers between approx. 164,000 and 182,000 and the sales books have not yet been quantitatively evaluated - there are probably only a few thousand of these pieces. This model initially had no successor and from the 1880s onwards you can occasionally find AGASSIZ chronographs with LONGINES signatures. After the 20 H, the caliber 19 CH came onto the market in 1889. The following chronograph seems to be an intermediate construction, it is not presented at all by Longines."

References:

http://www.pocketwatch.ch/klongines.htm
https://hans-weil.faszination-uhrwerk.de/Longines/longines.html
http://www.chronoguide-taschenuhren.com/chronograf.htm

DirtyDozen12

Thank you for sharing this wonderful watch.

Unfortunately, I do not have much information to add. As @Modest_Proposal wrote, the movement is a caliber 19CH, which was Longines' second chronograph movement. As shown above, there are two variants of the movement. Both are based on the time-only caliber 19A. This information comes from Patrick Linder's book on Longines, entitled "At the Heart of an Industrial Vocation".

As for your example, the condition is fantastic. Though I do not recall seeing another example with the same handset, the style looks appropriate for the era. The enamel dial is lovely, with red numbers for the chronograph minute counter and outer scale. I agree with your estimate of circa 1890 as the production or original invoice date. I suppose that the watch was originally sold in France, given the "M" by the stem.

Admittedly, I do not entirely understand how these chronograph movements work. I think that they use some sort of vertical clutch, rather than a horizontal clutch. I wonder if the chronograph is engaged/disengaged via a lever (red arrow) that acts on a vertical pin (green arrow), which is attached to a hidden lever (part number 506, Linder) that extends to the driving wheel (blue lever). In its current position (reset), the tooth of the lever is between columns on the column wheel. Starting the chronograph would cause the lever to pivot down and right, which would presumably move the pin and hidden lever away from the driving wheel.

Anyway, it is a fascinating and uncommon watch. Examples of Longines' first chronograph, the 20H, seem to be more common than examples of the 19CH.

DirtyDozen12

Thank you for sharing this wonderful watch.

Unfortunately, I do not have much information to add. As @Modest_Proposal wrote, the movement is a caliber 19CH, which was Longines' second chronograph movement. As shown above, there are two variants of the movement. Both are based on the time-only caliber 19A. This information comes from Patrick Linder's book on Longines, entitled "At the Heart of an Industrial Vocation".

As for your example, the condition is fantastic. Though I do not recall seeing another example with the same handset, the style looks appropriate for the era. The enamel dial is lovely, with red numbers for the chronograph minute counter and outer scale. I agree with your estimate of circa 1890 as the production or original invoice date. I suppose that the watch was originally sold in France, given the "M" by the stem.

Admittedly, I do not entirely understand how these chronograph movements work. I think that they use some sort of vertical clutch, rather than a horizontal clutch. I wonder if the chronograph is engaged/disengaged via a lever (red arrow) that acts on a vertical pin (green arrow), which is attached to a hidden lever (part number 506, Linder) that extends to the driving wheel (blue lever). In its current position (reset), the tooth of the lever is between columns on the column wheel. Starting the chronograph would cause the lever to pivot down and right, which would presumably move the pin and hidden lever away from the driving wheel.

Anyway, it is a fascinating and uncommon watch. Examples of Longines' first chronograph, the 20H, seem to be more common than examples of the 19CH.

DirtyDozen12

That is high praise, thank you.


I suppose that depends on how you define an instantaneous minute counter. Sometimes the term is used to describe minute counters that advance semi-instantaneously (about 1 second) via a sliding wheel. To me, the 19CH looks to have this design, with the typical sliding wheel (red arrow), minute recording wheel (green arrow), and jumper spring (blue arrow). This design is in contrast to the instantaneous minute counter on Longines' next chronograph caliber, the 19.73. This design has no sliding wheel. Instead, the minute recording wheel is advanced instantaneously (fraction of a second) by an elaborate lever system (red arrow). The example shown below is a caliber 19.73N, which uses the same lever system as the caliber 19.73.

https://www.ebay.de/itm/264568918205

Syrte

I am speechless to see you buy something that’s not Omega. 😲
Of course I can’t blame you, congrats 👍