Whenever I see something I don’t understand I get curious. So the plaque in the picture below set me searching and I uncovered so much information that I had to stop digging. But I thought I would share some of it on my blog.
The only thing I thought I might have understood was the bit at the bottom. But then I thought 167 miles or metres, and could ch possibly mean chains? Surely not. Well, it turns out that m does mean miles and ch does mean chains (Remember 1 chain is 22 yards? I did not!). Then I thought, 167 miles from where?
I Googled BML3 30/231 and found the website abcrailwayguide.co.uk which correctly recognised the bridge as the Spa Road bridge in Radipole and it told me that BML3 is an ELR number. More searching indicated that ELR stands for Engineer’s Line Reference. This is a code applied to all railway lines in UK . (For a complete explanation and listing look at the mind-bogglingly extensive website.)
BML3 is the third section of the Bournemouth Mainline, running between Dorchester Junction and Weymouth. BML2 is the line from Northam Short Mile to Dorchester Junction and BML1 is the stretch of line from Waterloo to Northam Short Mile. So, you might think that the distance 167 m 22 ch would be the distance from Waterloo. Not so, For some reason I have yet to discover distances on BML3 are from Paddington following the line via Melksham.
At this stage I had explained everything on the sign. I was still a little perplexed about some things. Why use chains as units? But, on the whole, it was mission complete. I should have stopped. But no, I carried on digging.
I then found that the railway line has a Line of Route Code SW105, this being, you might think, the line from Waterloo; not so. From Paddington then? Not that either, but the line between Clapham and Weymouth. This line has Route Availability Code 8 which means it can take quite heavy trains but not the heaviest, which require Route Availability Code 10. Stations have CRS codes (Computer Reservation System). Weymouth’s is WEY and there is a listed station with CRS code WOY called Weymouth Olympic Games. Railway junctions have STANOX codes. Weymouth Jersey Siding Junction, for example, is 86982. At this stage I stopped but there is more of this type of stuff out there if you are interested. Good luck.