After last year’s return to Stranraer Harbour, it is time to pay another visit to south-west Scotland and to the four southernmost outposts of mechanical signalling on the Glasgow & South Western main line between Glasgow and Carlisle.
Three of the quartet are Glasgow & South Western Railway (G&SWR) designs, but a fascinating exception is the box at Thornhill, one of the few surviving and working examples on our rail network of a fortified war-time (LMS, 1943) ARP signal box.
My visits to this area were on two separate occasions, firstly by rail from Edinburgh to New Cumnock and Kirkconnel (8 March 2017) and then during the following month, and making rare use of a hire car after visits to Glenwhilly and Girvan, a look at the remote boxes at Thornhill and Holywood (26 April 2017).
GBRf 66750 “Bristol Panel Signal Box” passes New Cumnock on 8 March 2017 with empty coal hoppers from Tyne Coal Terminal bound for the nearby Greenburn open cast mine
Having noted, but sadly been unable to visit, the two other mechanical boxes along the G&SW on my rail journey south from Glasgow Central (Lugton and Mauchline), our first call is at New Cumnock, where an all-wooden 1909-vintage G&SWR box with a 40-lever frame stands just north of the station on the west side of the line (top photo and below).
156435 approaches New Cumnock on 8 March 2017 with the 13.15 for Carlisle
Semaphores to note here are an up starter (NC31) at the end of platform 2, a tall down starter on a bracket close to the signal box (NC13) at the north end of platform 1 (as seen above) and an up home signal some way beyond (NC32), with a small junction arm (NC29) controlling access to a loop east of the station, as seen above.
While my attention is normally on semaphore arms, another notable survival that caught my attention at New Cumnock is this interesting pair of shunting disc signals on a short lattice post, adjacent to the up platform.
Just over seven miles – or nine minutes by train – brings you to Kirkconnel, the only other open station on the G&SW route with a signal box and semaphores. The 1911 G&SWR box here stands some distance north of the station on the east side of the line, as seen above, and controls home and starter arms in each direction.
156435 departs Kirkconnel on 8 March 2017 with a Glasgow-Carlisle service
Continuing south, by road now along the A76 towards Dumfries, and after passing through the village of Sanquhar (station but no signal box) the next settlement you will reach is the small town of Thornhill, where its former station and signal box stand just over a mile north-east of the main street.
More than half a century after its December 1965 closure Thornhill station remains remarkably intact, with both platforms still in situ and an attractive and privately-owned station building standing on the up (southbound) side of the line, as seen above. It has been a longstanding candidate for re-opening.
The signal box here is a war-time LMS box dating from 1943, which was actually closed for a number of years before being re-opened in 2000 to handle increased traffic on the line, at a time when an up loop was reinstated and signal TH10, as seen in these photos alongside up home TH8, was commissioned.
156501 passes Thornhill on 26 April 2017 with the 10.13 Glasgow Central-Carlisle
Reading a fascinating account of WW2 ARP signal boxes by the Pill Box Study Group, Thornhill was one of around 45 ARP design signal boxes built during World War Two, with one of the largest and finest examples to survive being Crewe North Junction, which was built in 1940 and is now an impressive signalling museum within the Crewe Railway Heritage Centre.
ARP signal boxes were designed to prevent blast damage rather than a direct hit from a bomb, and LMS ARP boxes like Thornhill were only designed to resist a direct hit from a 1kg incendiary bomb.
They were generally built with 14″ thick brick walls, a reinforced concrete roof around 12″ thick, and concrete floors, with use of wood minimised to avoid the risk of fire damage. Pre-cast concrete staircases were also a feature of the LMS ARP signal boxes, as seen here at Thornhill.
Finally on this route, its most southerly mechanical signal box stands at remote Holywood, four miles north of Dumfries, where a G&SWR box dating from 1920 controls mechanically worked wooden gates on a quiet country lane around a mile from the village.
Pictured here is 66739 approaching Holywood on 26 April 2017 with a train of empty coal hoppers bound for Killoch Colliery.
Pictured below is Scotrail 156493 passing Holywood Signal Box with the 12.13 Glasgow Central-Newcastle service.
Despite having closed to passengers in September 1949, Holywood station is still signposted off the A76, and its up platform remains largely intact. A total of four semaphore arms can all be seen from a farm crossing over-bridge, to the south of the crossing, and comprise home and starting signals HW2/3 in the up direction and HW20/18 in the down (northbound) direction, all visible in the photo above.
My book “Britain’s last mechanical signalling” is available from publishers Pen & Sword, from good transport bookshops (when they re-open) and from many online retailers.