PHOTO GALLERY: NORTH BRITISH RAILWAY
Banavie Swing Bridge
OPENED: 1901 CLOSED: 1987
Click or tap the images for enlarged views
The contract for signalling the West Highland Extension line from near Fort William to Mallaig was, interestingly, let to the Railway Signal Company although at first glance their is little to show for it. A closer look at the signal boxes, however, shows them to be very similar to the standard RSCo signal boxes but for one feature – a hipped roof with large overhang. Perhaps the North British Railway specified this to comply with their own architectural policy.
The new line had to cross the Caledonian Canal, already served nearby by a short branch, and this required a swing bridge. This signal box controlled the single line through the station, three level crossings and the bridge.
The photographer is standing on the bridge in this view, and the apparatus that links the signal wires when the bridge is set for rail traffic can be seen in the foreground. Centrally between the two rails is a bolt mechanism that holds the bridge firmly in the correct position for trains to pass.
This delightful period image, taken only 13 years after the line (and signal box) opened, shows plenty of activity – passengers await the next train and a porter is in evidence with a trolley! Two platelayers are tidying the ballast.
In accordance with British Railways practice in Scotland the nameboards on each end of the signal box just proclaim it as “Banavie” but the original board was never removed from the front wall, still displaying its full name.
Although built by the Railway Signal Company, the lever frames were of the Stevens (Glasgow) design – again this was probably specified by the NBR in the contract.
W R Sykes & Co Lock & Block instruments were provided to give extra protection and interlocking between the bridge and the railway.
These Sykes instruments are for the Up line signals. The accepting instrument has no key release facility, as was practice on the NBR in Lock & Block areas.
Other features of interest in this view:
- There is a Sykes keyhole on the shelf to release the backlock on lever 13, the Up Inner Home that protects the bridge.
- An additional Sykes plunger has been mounted on the front of the instrument shelf marked “LEVER NO11 BRIDGE BOLT LOCK”. This would have electrically interlocked the levers with the various block instruments to ensure there were no trains signalled when the bridge needed to be released.
- On the right is a chunky switch marked “DISTANT ON OFF, PULL 9, 13 14”. When an Outer Home was provided, the distant lever was adopted for that purpose – for convenience the distant was altered to be worked by electric motor and operated from this switch.
The instruments at the left end of the instrument shelf were broadly similar, although only two were provided because there were only two Down signals. A similar keyhole and lower plunger are provided.
I do not pretend to fully understand the functions of these instruments – close study of the lettering on them suggests that they do not operate in the conventional manner of Lock & Block instruments. At least one is marked Camus Na-Ha (closed in 1964) but at this date (1972) working to Annat. The boxes that existed varied over the years but what is clear is that several successive signal boxes had no crossing loops or other passing facilities and care would have had to be taken to ensure trains didn’t enter the multiple sections from either end simultaneously. These boxes can be summarised as follows:
Signal boxes between Mallaig Junction and Glenfinnan
|Mallaig Junction||Tablet station||Crossing facilities|
|Banavie Junction||Tablet station||No crossing facilities||Abolished 1921|
|Banavie Swing Bridge||Tablet station||No crossing facilities|
|Tomonie||Not a tablet station?||No crossing facilities||Abolished 1912|
|Corpach||Not a block post||-||-|
|Annat||Tablet station||No crossing facilities||Opened 1964|
|Camus Na-Ha||Tablet station||No crossing facilities||Opened 1942
|Glenfinnan||Tablet station||Crossing facilities|
These instruments, however, I do understand:
Here we have a pair of Tyer & Co No 6 Tablet Instruments working to Mallaig Junction (left) and Annat (right). Notes accompanying the photograph suggest the latter had worked to Glenfinnan before Annat was commissioned in 1964.
Between the tablet instruments is a W R Sykes & Co “centre pillion” instrument similar to that at Beddington Lane. Levers on the front were operated to select the direction of trains to prevent trains being accepted in opposite directions – there was nowhere to cross trains here! At 1972 this device would have dealt with the single line well but it would not have been sufficient when other intermediate boxes without loops existed (see table above) unless all boxes had them and they were interlocked with each other in some way.
The 1943 London & North Eastern Railway Appendix gave instructions on operation:
Before Canal Bridge signal box can give permission to either side to take out a tablet, the slide control switch which is fixed between the two tablet instruments must be turned to right or left according to the station requiring the tablet. The switch must be lifted up, and it will then remain locked until the tablet is inserted at the Home station or if it is to be replaced again at the Distant station, when the instrument is dropped to “FREE” releasing the switch.
Before the signalman can turn the commutator to “TABLET OUT” he must press home the respective plunger after which he will be able to lower the starting signal. Treadles are placed ahead of these signals at canal Bridge releasing the instrument after which the signal lever may be replaced and it will become front-locked again to the tablet instrument.
In this photograph, the switch has been locked in the left position indicating that a tablet has been released at Mallaig Junction.
Soon after the above photograph was taken, the tablet working was replaced by Tyer key token.
Banavie Swing Bridge signal box closed on 14th June 1987 when operations were taken over by a new box at Banavie which ultimately controlled the Radio Electronic Token Block operation introduced throughout the area. It was built in a distinctly familiar style.