Eadie Bros & Co Ltd

This is my maternal grandfather’s ruler, one of them anyway. It is a folding three foot ruler with beautifully machined brass fittings and is marked for grandpa’s employer. 
The family story is that during WW1 and the 1916 shell crisis, grandpa was senior engineer for Eadie Bros and was sent down to London to offer the company’s engineering expertise and services to help alleviate the problem.
So there you are, a little snippet of family history.
As grandpa must have retired from the company sometime in the 40s, this ruler must be at least 75 years old, and probably a whole lot more. 
If any Blippers out there have any knowledge/information on Eadie Bros Ltd I would be most interested.