|Two Rotherham 19J watches from 1910, one size 12 the other size 16.|
The two watches above both have the classic 19J three-quarter plate pin set movement by Rotherham, one in size 12 the other size 16. Both are from 1910 and coincidentally I acquired them on the same day from different sellers. One interesting point is the difference in serial numbers.
|The size 12 is number 293,062.|
|The size 16 is number 148,956.|
The reason is that Rotherhams used multiple serial number ranges, I don't know how many but at least the two shown by these examples, one for size 0 and 6[i] , at least one for earlies models and probably more. This makes it difficult to determine the companies total production which Cutmore[i] estimates at about 600,000 in total over 50 years. It can also make dating watches in filled gold cases tricky if the movement is an unusual size.
[i] Watches 1850 – 1980 M. Cutmore, David & Charles, 1989
The size 16