Mirfield Resignalling

[pitdiver]

I have just watched Don Coffey's excellent video on the TRU. The route as you will be aware goes through Mirfield. This reminded me of an article in an old railway annual that my parents had given me for Christmas many years ago. It talked about the Resignalling of Mirfield. Does anybody know what this was all about as Mirfield seems quite insignificant to warrant a full article in a railway annual

 

[Railsigns]

The LMS's resignalling at Mirfield in 1932 has an important place in history as the only significant British colour light signalling installation based on speed signalling principles, as opposed to the usual route signalling.

 

[Elecman]

Mirfield was a unified significant Speed signalling installation carried out by the LMS in this country.

Edit Railsigns beat me to it above

 

[John Webb]

There is a detailed explanation of the Mirfield speed signalling at https://signalbox.org/signals/lms-speed-signalling/ It was replaced around 1970 by a more conventional scheme.
The Mirfield scheme is also covered in Kitchenside & Allen's book "Two Centuries of Railway Signalling" Chapter 12, and Michael A Vann's book "An Illustrated History of Signalling" (Chapter 4).