I'm brand new to your site but it looks like there are some decent folks and not without good wit. I found the forum here trying to find some info on a pocket watch that belonged to my Grandfather.
It's face reads 'La Salle Express', '21 jewels', and 'made in Switzerland'. Inside the back cover it shows 'Derby Rollerplate Sturdy' and 'case made in Canada'. It's stamped with 4219123 and freehand engraved with 111974B.
The mechanism itself is marked with 'La Salle Watch Co.', 'Made in Switzerland', '21 Jewels', and has some kind of adjustment.
The watch works perfectly. I'm sure that my Grandfather had it for a long time and he passed in the early eighties. I've had it since then.
I'm also trying to nail down an approximate age and any other details I can learn about it before putting it up on Ebay.