Back when trains were first connecting America’s coasts, a railroad worker’s watch would be worn through some tough conditions.
First, it must endure temperature and humidity changes, as well as changes in magnetic fields.
That’s not to mention regular wear and tear a watch will be presented while working a long day on the railroad. When railroad watches were inspected, they were to run within 30 seconds accuracy.
The Elinvar metal alloy set out to help protect watches from those conditions.

Introduced as the 922 Elinvar Watch Movement, the device differs from the 992 Movement by replacing the conventional steel hairspring with a mono-metallic balance wheel and an Elinvar hairspring.
The movement helps against declining elasticity that steel hairsprings tend to see when temperatures rise, making them weaker. This means a watch would run slowly when warm and faster when cool.
As trains need to run on a precise time schedule, it only makes sense that a railroad worker’s watch must be exact.
The time error can be made up by using a bimetallic balance to help a watch keep steady time when heated up or cooled down.

The Elinvar development meant a metal which would be automatically temperature compensated, so that correct time would be kept regardless of temperature changes.
The Elinvar movement also had other favorable aspects. Because it was made from nickel-steel alloys, it was rust-proof, something other steel hairsprings did not have the benefit of being. Watches with the Elinvar also help against magnetization.
In short, the 922 Elinvar eliminates time changes stemming from damaged mainsprings to keep the watch maintained to its factory standards.

Mark Sirianni Watch Repair
25 Fraley Street
Kane, Pa. 16735
814-837-9435
814-558-4818 (cell)
watchdoctorpa@gmail.com

9 Comments
Warren Wagoner
Really informative – Thanks !
Warren in Phoenix
Gary A
Thanks for yet more great information on railroad pocket watches. I especially enjoy hearing anything about them. I have a very modest collection of 6 from Hamilton, Elgin, Illinois and Waltham. You’ve serviced 4 just 2 more to go as my extra $$ become available. I love the workmanship that went into these and the service they provided.
Johnny
I also have a bunch of pocket watches and several of them are actually railroad watches that you have to take the front off of and pull a little lever to set them and then you screw the front back on. I have one in particular (you serviced) that has fancy scroll work inside and actually signed inside. I can’t recall the name but it is a large and heavy pocket watch and made by Illinois Watch Company, and it is very accurate for a mechanical watch, Gaining/losing less than one minute a week.
Charles tortorice
Mark,
I’m happy to see an article dealing with pocketwatches.
There still are devotees of these as evidenced by the huge number of eBay listings , in excess of 50,000 on a regular basis.
The craftsmanship and beauty of many of these pieces of history provide a glimpse into the day when QUALITY VERSUS QUANTITY was the rule, not the exception.
I’d love to see a review of some of these masterpieces.
The craftsmanship and beauty
Paul A. Baluch
Love your articles. Did all of the 922’s after 1931 have the Elinvar movement, or is there a particular series of serial numbers, or starting serial numbers, or just the ‘Railroad’ 922’s?
Melvyn Schuman
I own a pocket watch with the Elinvar movement. Thank you for the article.
Mark Morgab
Great information thank you
Patrick B
Mark,
Great article. I love my Hamilton.
Greg Keefer
Very informative. Thanks Mark