WRUW Today?

Dash 68

And here is the Hamilton that replaced the 992. This is the 992E (for Elinvar). The handsome example posted by @noelekal has a steel and brass bi-metallic, temperature compensating balance wheel with split rim, and blued steel Breguet hairspring. The 992 was not anti-magnetic. Electric urban and inter-urban trains were introduced circa 1898, and this posed a problem for watches that were not anti-magnetic. The 992E was not the first anti-magnetic, railroad standard pocket watch, (Swiss makers had them, and some American watchmakers imported the Swiss material.) But the 992E was an early anti-magnetic model for Hamilton. The difference between the two models is that the 992E had a solid rimmed, Elinvar balance wheel (anti-magnetic, and unaffected by temperature change), and an Elinvar monometallic hairspring (likewise not affected by temperature change or magnetism). The 992E was introduced in 1931. The easiest way to identify a 992E is by the word Elinvar marked on the pallet bridge as indicated by the arrow. The mono-metallic balance wheel is also easily identified. And the white alloy Elinvar hairspring on some models. On this particular 992E, the Elinvar hairspring has been dyed BLUE because of complaints from retailers and watchmakers who hated the white alloy Elinvar hairspring. This later changed, and Hamilton quit dying these hairsprings. Are wrist watch collectors interested in such details?