How widespread was Lock and Block?

[The Stationmaster]

1 hour ago, beast66606 said:

 

There existed a free pull at Ellesmere Port No.2 (iirc) until the mid 1970s, and this on a (double track) line with passenger trains and Stanlow tank trains !

I'm not surprised at all by that as there were various locking 'anomalies' still around in the 1970s.  c.1975 we were required on the Western to carry out a survey of movements being made from ground signals over unsignalled routes (and I don't mean past yellow discs).  At one of my 'boxes - which had received a new frame and locking in 1949 - we were making anything between 20 & 30 movements a day, including propelling freight trains but mainly light engines, past one particular disc which could not be cleared for that route.  Off went the completed forms and we heard no more of it.  And that situation lasted until the 'box was overtaken by resignalling nearly 10 years later.

 

Another interesting feature on the Western was the way the berth track circuit at Home Signals was arranged to interact with the block which was rather odd (to my wat of thinking).  If the block was at 'Line Clear' and the berth track was occupied the block would drop to 'Normal' instead of going to 'Train On Line' but at least you couldn't then peg 'Line Clear' until the track cleared.   Very odd if you knew Welwyn Control principles so I checked with the S&T if I was reading the circuits properly - I was.

[micknich2003]

Here are drawings of the H&BRly type of Sykes "Lock and Block".

 Despite almost sixty years of collecting, I have to date, never seen a interior view of a H&BRly 'box with these instruments.