Early Signalling at Midford
When the Bath Extension first opened, the single-line block working was controlled by block telegraph without a train staff. Under the terms of the Somerset & Dorset Railway’s (S&DR) 1874 undertaking to the Board of Trade (BoT), the first block post south of Bath was officially supposed to be at Wellow. However, evidence from the BoT’s report on the Foxcote disaster of August 1876, near Radstock, suggests that Midford station was already acting as an intermediate block post by that time.
The precise details of Midford’s original signalling arrangements remain unclear, but it seems likely that Distant and Home signals were provided in both directions, worked from a small lever frame—probably housed in a wooden hut on or near the platform. Despite the Foxcote accident, which highlighted potential weaknesses in signalling arrangements, it appears that Midford continued to function as a block post for some time. This is confirmed by references in the S&DJR’s Working Timetable Appendix No. 7, dated 1 March 1886, indicating that Midford was still part of the operational signalling system.
A major change came on 3 October 1886, when Electric Train Tablet (ETT) working was introduced between Bath and Radstock, using Tyers No.1 instruments. With this upgrade, Midford ceased to be a block post and became a non-block location within the Bath Single Line Junction–Wellow section. However, the station’s signals appear to have remained in use for station stop purposes only, rather than for block working.
The steep climb out of Bath meant that banking engines were required for almost all Down freight trains, though assistance was needed only as far as the summit at the northern entrance to Combe Down Tunnel. To regulate this operation, a special banking system had been in place since 1876 on the Bath Single Line Junction–Midford section, involving the use of a “Bath Bank Staff”. This arrangement continued even after ETT working was introduced.
It is believed that the Bank Staff system was officially brought into use on 22 December 1876 by S&DJR Signal Instruction No.1, though no copy of this document has yet been found.
1892 Doubling of the Line
In 1892, the section of railway between Midford and Wellow was double-tracked, and new signal boxes were installed at both locations. The upgraded infrastructure was officially brought into use on 28 August 1892 (as recorded in The National Archives file MT6/598/1). As part of these changes, Midford once again became a block post, working Electric Train Tablet (ETT) to Bath Single Line Junction, most likely using the Tyers No.1 instrument previously located at Wellow. The section between Midford and Wellow operated under Absolute Block, using the S&DJR block telegraph system. The “Bath Bank Staff” arrangement remained in place, though now interlocked with the ETT instrument at Bath Single Line Junction signal box to ensure greater operational safety.
The new Midford signal box was constructed on the Up side of the line, situated between the south end of the platform and the viaduct. Built to the S&DJR Type 2 design, it featured a gable-roofed timber superstructure with a stone base, a brick rear wall, and a brick chimney stack. The distinctive wavy valencing along the eaves was a typical decorative feature of S&DJR signal boxes from this period.
With the introduction of double track, the new layout extended across Midford Viaduct, with a crossover (points 9) located approximately halfway along. The Up Inner Home signal (14) was mounted on a wooden post bolted to the outside of the viaduct, a necessity given the confined space available. A distinctive feature of early S&DJR double-line signalling was the inclusion of subsidiary arms beneath the main stop signals located at the rear of section signals. At Midford, one such example was signal 3PUSH, a full-size subsidiary arm with a ring, operated via a push-pull lever (lever 3). This lever had a mid-stroke position, allowing the signalman to either pull back to operate the main or push forward to clear the subsidiary signal.
It is believed that all original main running signals installed in 1892 were lower-quadrant (LQ) arms on wooden posts. Around 1900, three key additions were made to Midford’s signalling, as reflected in the circa-1912 signalling diagram. Lever 12 was introduced to control a subsidiary ringed arm beneath the Up Outer Home (15). Its precise function remains somewhat unclear—while it was recorded in the lever-frame locking table as a “Shunt By” arm, railway notices often referred to it as a “Calling On” arm, and by the British Railways (BR) era, it was designated a “Warning” arm. This signal allowed movements into the Up Siding, as the Up Outer Home could only be cleared if the Inner Home had already been pulled off.
At around the same time, lever 5 was brought into use as another push-pull lever. The 5PUSH function controlled a new ground signal, positioned on the outside of the Down line just south of the facing points (8), which authorised movements from the Down line back onto the single line. The 5PULL function operated what became one of Midford’s most notable signalling features—a “wrong-road” signal mounted on the platform. This was likely the first signal at Midford to be installed on a lattice metal post.
By 11 June 1929, a second wrong-road signal was added at Midford under S&DJR Signal Instruction No. 293. This new signal acted as a “repeater” arm for 5PULL, positioned beneath the Down Home signal (2), which itself stood atop the “Long Arch” overbridge. These signals were primarily used in the event of an Up Goods train failing to complete the steep climb towards Combe Down Tunnel on the 1-in-50/1-in-100 gradient. In such cases, the driver would use a telephone provided for the purpose at the south end of Combe Down Tunnel to contact the Midford signalman and request permission to set back to the station. Once back at Midford, the train could either be shunted onto the Down line or, depending on operational needs, held on the Up line while awaiting an assisting engine or building up sufficient steam to attempt the climb again. It was for these Up line reversals that signal 5PULL was used.
There is no known record of any “Limit of Shunt” indicator on the Up line to restrict wrong-direction movements back towards the Up Outer Home (15) or beyond. It has been suggested that the Sykes interlocking system, introduced in conjunction with block working to Wellow, may have been considered sufficient to prevent conflicts with Up trains approaching from the south.
Layout Alterations
In the original 1892 layout, the only provision for goods traffic was a single siding trailing off the Up line south of the viaduct. This siding was controlled by a ground frame (GF) housed in a small wooden hut, secured by a bolt lock operated by lever 11 in the signal box. However, in December 1894, a small goods yard was opened north of the station, providing additional facilities with two sidings.
The new yard was located on the Down side of the line, just beyond the ‘Long Arch’ overbridge on the Bath side. It was accessed via a trailing point on the single line for Down trains and controlled by a dedicated ground frame (GF) housed in a small wooden hut on the Up side of the line. This frame was released by the single-line tablet. With this addition, the original GF at the Up Siding became known as GF ‘B’, while the new ground frame for the goods yard was designated GF ‘A’. Both ground frames also controlled ground signals for shunting movements in and out of their respective sidings.
The crossover (points 9) on the viaduct appears to have been of limited practical use and was eventually removed, along with its associated ground signals (10PUSH and 10PULL). This alteration was authorised by S&DJR Officers’ Minute 7013, dated 26 April 1918.
As part of a broader programme to improve speed restrictions on the line, significant changes were made on 9 April 1933. The facing points (8) were moved further south along the viaduct, raising the Up train speed limit from 20 mph to 40 mph. The relocated points were now 98 yards south of the signal box, while ground signal 5PUSH was repositioned between the Up and Down lines, 206 yards from the signal box (S&DJR Signal Instruction 330). This modification also involved moving the Up Inner Home bracket signal (14) 206 yards south of the signal box, while the Down Advanced Starting signal (4) was relocated to 470 yards. These changes took effect the previous weekend on 2 April 1933.
After 1933, Midford’s general layout remained unchanged until 1959–60, when the Up Siding and GF ‘B’ were taken out of use. It appears the siding itself was first taken out of use in June 1959 (BR(SR) Weekly Notice P/EW21), while GF ‘B’ was permanently abolished on 28 February 1960 (BR(SR) Weekly Notice P/EW9), after which the remaining infrastructure was removed. However, there is some inconsistency in historical records, as a 1960s BR(WR) locking sketch copy suggests that GF ‘B’ was abolished in December 1959.
The goods yard and GF ‘A’ were closed in 1963–64, with the infrastructure officially removed on 29 June 1964.
Signal Alterations
Midford’s signalling underwent numerous modifications throughout its operational life. One of the earliest changes came on 15 April 1913, when signal 3PUSH was abolished (S&DJR Signal Instruction 237). From that point onwards, lever 3 became a normal lever, controlling the Down Starting signal only.
By 1922, the original Up Inner Home signal (14) had been replaced by a right-hand lattice bracket, positioned just south of the viaduct. As part of the 1933 layout alterations, this signal was moved further south to a position 206 yards from the signal box, while the Down Advanced Starting signal (4) was relocated to 470 yards. Both changes took effect on 2 April 1933 (S&DJR Signal Instruction 330). At the same time, ground signal 5PUSH was repositioned between the Up and Down lines, 206 yards from the signal box. Later that year, on 21 May 1933, the ground signals at GF ‘B’ were removed (S&DJR Signal Instruction 336).
Adjustments to distant signals also occurred during this period. The Up Distant signal (16) was lowered by 12 feet on 2 September 1924, followed by the Down Distant signal (1), which was reduced by 6 feet two days later (S&DJR Signal Instruction 276). A significant incident occurred on 29 July 1936, when the Down Starting signal (3) was demolished due to an accident involving a runaway train. Evidence suggests that the original post was re-erected in a shortened form, possibly marking the introduction of upper-quadrant (UQ) arms at Midford. This may have been the first UQ arm installed at the station, setting a precedent for all later signal replacements until 1960. The Down Distant signal was replaced with a new 15-foot post on 22 March 1942, while the Up Starting signal (13) was renewed with a 25-foot post on the same date (S&DJR Signal Instruction 389).
Further changes took place on 25 July 1948, when the Up Outer Home signal (15) and its subsidiary “Shunt By” arm (12) were replaced with new signals on a 20-foot post, positioned 81 yards further from the signal box. The subsidiary arm (12) was also redesigned, becoming a small horizontally-striped “Warning” signal, accompanied by an indicator box mounted on the signal post. A photograph from this period shows the “Rule 55 exempt” white diamond sign, marked with a large black “T”, indicating that a telephone was provided inside the white cabinet with a black-and-white striped plate in the foreground. On the same day, the Up Distant signal was replaced by a new 12-foot post, positioned 306 yards further from the signal box, bringing it to a total distance of 1,000 yards from the relocated Up Outer Home. However, signal 12 was later removed on 28 February 1960, coinciding with the closure of the Up Siding. Despite this, a 1960s BR(WR) locking sketch copy confusingly suggests that the signal may have been abolished as early as December 1959 (Weekly Notice P/EW9).
By 1955, Midford’s signalling had become as varied as that found elsewhere on the S&DJR. Some signals remained on lattice posts, while signals 1 and 16 were now on SR-type rail-built posts with upper-quadrant (UQ) arms. Signals 3 and 4 were still mounted on wooden posts, though signal 3 carried a UQ arm, while signal 4 was a tall post with a lower-quadrant (LQ) arm. Signals 13 and 15 also had UQ arms, but the remaining signals—2, 5PULL, and 14—retained LQ arms. GF ‘A’ still had Stevens ‘flap’ ground signals for movements into and out of the goods yard, while 5PUSH had by then been replaced with a standard Westinghouse “half disc” ground signal. Interestingly, while signal 1 had a rail-built post, signals 15 and 12 remained on a lattice post, despite both being renewed on the same date. This inconsistency suggests that the signal engineers continued to re-use available equipment whenever practical.
By May 1955, the ground signals at GF ‘A’ were still in place, but they had been removed by June 1958. The access point to the goods yard was renewed in early 1956, and it is likely that the associated ground signals were removed at the same time.
One of the last major alterations at Midford took place on 11 September 1960, when signals 3 and 4 were replaced. Both were renewed as standard BR(WR) LQ arms on tubular steel posts. However, because the new signal 4 was considerably lower than the old one, its light was no longer clearly visible to the signalman, necessitating the installation of a lamp repeater inside the signal box (a mechanical arm repeater was already in place). Apart from a solitary example at Masbury, these were the only known BR(WR) signals on the S&DJR until a similar installation was introduced at Highbridge in March 1966.
Block Working
When the Bath Extension opened in 1874, Midford appears to have functioned as an intermediate block post within the single-line section between Bath Junction and Wellow. At this time, block working was controlled by block telegraph alone, without the use of a train staff. However, this arrangement ceased on 3 October 1886, when Electric Train Tablet (ETT) working was introduced between Bath Single Line Junction and Wellow, using Tyers No.1 instruments.
With the 1892 doubling of the line to Wellow, Midford once again became a block post, now working ETT to Bath Single Line Junction and Absolute Block to Wellow, using the S&DJR block telegraph system. It is presumed that the ETT instrument at Midford was the Tyers No.1 machine previously located at Wellow. Meanwhile, the “Bath Bank Staff” system remained in use at Bath Single Line Junction, but Midford no longer played any direct role in its operation.
In 1912, the original Tyers No.1 ETT instruments were replaced with a more modern system, assumed to be Tyers No.6, which was already in use elsewhere on the S&DJR and is known to have remained at Midford until closure. Although British Railways (Western Region) later considered replacing ETT with Electric Key Token working on this section, the Tyers No.6 system remained in use until the line closed.
When a tablet was removed from the ETT No.6 instrument at Midford for an Up train, an electric lock on lever 13 was released, allowing the signalman to clear the Up Starting signal for the train’s departure toward Bath Junction. However, there is no known evidence that a “one pull only” restriction was included in the electrical locking system (click here for more details on ‘tablet out releases’ on the S&DJR).
The 1948 Electrical Locking table records that a tablet out release from Bath Junction was also required to release electric locks on levers 5PUSH and 14, though not on 5PULL. This ensured that any movement past these signals would only occur when the single-line section was clear—even if the train was not proceeding beyond the Up Starting signal. Interestingly, the signal diagram does not specifically annotate these releases, as was common practice in later years, but the electrical wiring diagram suggests that the locks on 5PUSH and 14 were engaged when the signalman turned the commutator of the ETT No.6 instrument to the left after receiving a release from Bath Junction, without needing to physically withdraw a tablet.
Signal 5PULL controlled movements from the single-line back onto the Up line. However, such wrong-line moves created potential conflicts with the Absolute Block working to Wellow, as they could not be made if an Up train had already been accepted from Wellow. To prevent this, Midford was equipped with a Sykes ‘plunger lock’ instrument, fitted with a Sykes ‘point & plunger lock’ (P&P).
Before the signalman at Midford could give “Line Clear” to Wellow, the P&P lock handle had to be placed (or kept) in the right-hand position. Only then could the signalman operate the plunger on the Sykes instrument, which in turn released an electric lock on the pegging handle of the three-position block telegraph instrument. At the same time, this action released the electric lock on lever 6 in Wellow signal box, allowing the Up Advanced Starting signal at Wellow to be cleared. The Sykes instrument remained locked until signals 15 (or 12) and 13 had been pulled and replaced, confirming that the Up train had arrived from Wellow, passed through Midford, and was en route to Bath Junction.
With the P&P lock handle in the right-hand position, levers 5PULL and 11 were also locked, preventing any shunting or use of the Up Siding points that could potentially foul the clearing point in advance of the Up Outer Home (15).
To use signal 5PULL or unlock GF ‘B’ via lever 11, the signalman first had to ensure that the Sykes plunger lock instrument was in its normal state. This required moving the P&P lock handle to the left-hand position, which in turn locked the plunger in the Sykes instrument, preventing the acceptance of an Up train from Wellow. Once signal 5PULL had been used, the Sykes plunger remained locked until lever 5 was returned to its normal mid-way position and lever 13 (the Up Starting signal) had been pulled and replaced, confirming that the train had proceeded beyond the clearing point and an Up train from Wellow could now be accepted.
Despite the similarity of the Sykes instruments used at Midford, this was not an example of Sykes ‘Lock & Block’ block working. The exact installation date of the Sykes equipment at Midford remains uncertain, but it is probable—though not confirmed—that it was introduced at the same time as signal 5PULL.
Treadles and Track Circuits
Several treadles were installed at Midford to assist with block and signal interlocking, providing the signalman with visual and audible indications of train movements. These treadles were labeled ‘A’, ‘B’, and ‘C’, with an additional treadle ‘E’ positioned on the Up line, just behind the Up Outer Home signal (15). When activated, treadle ‘E’ triggered a warning buzzer in the signal box and illuminated a ‘Train Waiting’ indicator on the instrument shelf. This indicator remained active until the signalman cleared signal 15 or 12, providing a safeguard against trains being overlooked while standing at the signal.
Around 1923, a track circuit ‘A’ was installed on the Down line, stretching 1,000 yards south from a point near ground signal 5PUSH. The track circuit extended beyond the Down Advanced Starting signal (4), which was located in a curved cutting. Due to restricted visibility, the signalman could not see far beyond signal 4, making it difficult to determine whether a Down train had fully cleared the gradient. The new track circuit ‘A’ solved this problem, allowing the signalman to confirm that the rear of a Down train had passed beyond the end of the 1-in-60 uphill gradient.
On 4 April 1933, signal 15 was fitted with a diamond sign, as recorded in S&DJR Signal Instruction 331. This indicated to train crews that, if detained at the signal, they did not need to follow Rule 55, which ordinarily required the fireman to walk to the signal box and report the train’s presence. Instead, the ‘Train Waiting’ indicator, activated by treadle ‘E’, would notify the signalman automatically. Curiously, despite the presence of track circuit ‘A’, a diamond sign was never installed on signal 4, leaving crews stopping there still subject to Rule 55 procedures.
In March 1952, a second track circuit ‘B’ was introduced, covering the facing points (8) and extending from signal 3 towards signals 14 and 5PUSH, where it abutted track circuit ‘A’. It was likely around this time that the ‘Last Vehicle’ treadle ‘B’ was removed, as the new track circuit provided a more reliable method of detecting train movements over the points.
Midford Signal Box
The 1892 signal box at Midford was originally constructed in the S&DJR Type 2 style, featuring a gable-roofed timber superstructure with wavy valencing, resting on a stone base. The rear wall and chimney stack were built in brick, a typical feature of signal boxes on the Bath Extension. However, the box underwent a dramatic alteration following an accident on 29 July 1936, an event described in “Red for Danger”, though the book records an incorrect date.
The accident itself, though potentially serious, had humorous elements. A runaway locomotive—which had been shunting at Writhlington (north of Radstock)—escaped without its crew, propelling eight empty wagons down the Up line. On reaching Midford, the leading wagon derailed at points 8, which were still bolted for the Down line. At precisely 10:06 am, according to the signal box clock, the wagon smashed into the base of the signal box, tearing a large hole in the wall and shifting the lever frame, before coming to rest on the platform.
As a result of the damage, the signal box was rebuilt with a flat roof, a significant departure from its original design. The reason for this alteration remains uncertain—possibly a matter of expediency. Records indicate that a temporary box was dispatched from London, though details of its use remain unclear. The damaged box was ultimately rebuilt by Hayes & Sons of Bristol, and the rebuilt flat-roofed signal box can be seen in the photographs in the Introduction section.
Inside Midford Signal Box
A photograph from 23 May 1957 provides a rare glimpse into the interior of the rebuilt signal box. Despite various upgrades, it retained a general L&SWR/SR appearance.
The 16-lever frame, manufactured by Stevens, was of the direct tappet pattern, with levers spaced 4⅛ inches apart. Notably, the ‘push-pull’ lever 5 is visible in its mid-way position, while lever 8 is reversed. The lever description plates were of the L&SWR rectangular brass type, except for the white-painted spare levers (6, 9, and 10). However, following the abolition of levers 11 and 12 in 1959–60, their plates were replaced by the BR(WR) rectangular type, featuring “Traffolyte” faceplates mounted near the tops of the levers. These newer plates are visible in a circa-1965/66 colour photographs.
| Lever | No. | Nomenclature | Requires |
|---|---|---|---|
  | 1 | DOWN DISTANT SIGNAL | 4 3 2 |
 | 2 | DOWN HOME | 7 |
| 3 | DOWN STARTING | 7 |
| 4 | DOWN ADVANCED STARTING | |
| 5 PULL | ? | 8 |
| 5 PUSH | ? | ||
 | 6 | ||
 | 7 | F. P. LOCK ON 8 | |
 | 8 | DOWN FACING POINTS | |
| 9 | ||
| 10 | ||
 | 11 | RELEASE LOCK TO GROUND FRAME | 8 |
| 12 | ||
| 13 | UP STARTING SIGNAL | |
| 14 | UP INNER HOME | 8 |
| 15 | UP OUTER HOME | 14 |
| 16 | UP DISTANT SIGNAL | 13 14 15 |
In the front left-hand corner of the signal box, atop a cupboard, stood the Tyers No.6 ETT instrument, with its foot plunger set into the floor in front of the cupboard. Nearby, an iron ring handle was set into the floor, which, when pulled vertically, operated a wire that turned the Whitaker ‘pick-up’ apparatus arm 90 degrees, ready to receive a tablet pouch from a passing locomotive. Several Whitaker pouches can be seen hanging on the wall to the left of the cupboard, with larger hand-exchange pouches hanging from the window frame above them.
| Name | Description | Collection |
|---|---|---|
| Bath Junction Tablet Tablet Instrument | Tyres No. 6 |  |
Above the lever frame, the instrument shelf housed a variety of essential signalling equipment. From left to right, the following devices were present:
| Name | Description | Collection |
|---|---|---|
| Bath Junction Block Bell | The block bell to Bath Junction, which worked in conjunction with the Tyer’s No 6 instrument. Midland/LMS Non-tapping with mushroom bell | |
| Wellow Block Bell | The block bell to Wellow (of the type with a built-in ‘tapper’). GWR/WR Thompson tapping instrument with cowbell | |
| ‘A’ Treadle Bell | Indicator Bell – unknown origin | |
| Lamp Indicator for 5 signal | GWR/WR Thompson (provided in September 1960) | – |
| Wellow Double Line Block Instrument | A standard S&DJR Block Telegraph ‘pegging’ instrument for the Up line, but with an additional upper indicator for the Down line instead of the usual separate ‘non-pegging’ instrument. Midland Railway “pin and chain” pegging instrument with a Southern Railway non-pegging unit mounted above it. | |
| ‘B’ Track Circuit Indicator | GWR/WR Brass Indicator | |
| ‘A’ Track Circuit Indicator | GWR/WR Brass Indicator | |
| Train Waiting Buzzer | | |
| Sykes “Indicator Lock” | Showing whether the back-lock on the Up Starting signal (No 13) was ‘locked’ or ‘free’. Released by treadles ‘A’ or ‘B’. The Back-lock on 3 was removed in 1952. Brass plate “(3) 13 OVER (LOCKED / FREE) TO TREADLE” | |
| Sykes “Plunger Lock” with Point & Plunger Lock. | Back-locks on signals 5 PULL, 12 and 15, released by treadle ‘C’. Plunger released lock on Up Line block instrument commutator, and also Up Advanced Starting at Wellow. Fitted with P&P lock. Brass plate Sykes Lock n block lots of controls “5 PULL 11 OVER 15 (LOCKED /FREE) TO STARTER (TRAIN ON/Blank) FROM WELLOW” | |
Along the front of the instrument shelf, a series of signal arm and lamp repeaters displayed whether a signal arm was “on” or “off”, or whether its lamp was lit. Several circular plungers, mostly in brass cases, were also positioned here, controlling the electric locks on certain levers in conjunction with track circuits and interlocking. Among these, two plungers were housed in bakelite cases.
| Name | Description | Collection |
|---|---|---|
| ‘1’ Lamp Repeater | Sykes SR Shelf Repeater – LIGHT In/Out (black needle) | |
| ‘1’ Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (yellow needle) | |
| ‘2’ Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (red needle) | |
| Plunger | SR Brass Plunger for 3 | |
| ‘4’ Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (red needle) | |
| Plunger | SR Brass Plunger for 5 | |
| ‘5PULL’ Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (red needle) | |
| Plunger | W.R. Bakerlike Plunger for 7 | |
| Plunger | W.R. Bakerlike Plunger for 8 | |
| Release Key | Sykes Release Keyhole | |
| Release Key | Sykes Release Keyhole | |
| 12 Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (red needle) | |
| Plunger | W.R.Sykes Brass Plunger for Lever 13 | |
| Plunger | W.R.Sykes Brass Plunger for Lever 14 | |
| 15 Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (red needle) | |
| 16 Signal Repeater | SR Shelf Repeater – S.R.ly On/Wrong/Off (yellow needle) | |
| Train Waiting Indicator | SR Shelf Repeater – Blank/Train Waiting (green needle) operated by Treadle ‘E’ | |
| 12, 15, 16 Light Repeater | SR Shelf Repeater – Light In/Out (black needle) | |
A brass push-button, recessed into the front of the instrument shelf, was located between the plungers for levers 7 and 8. Although its exact function is unknown, it may have been an economiser plunger, used to release the electric lock on the block instrument’s commutator handle after the signalman had plunged on the Sykes ‘plunger lock’ instrument.
Lighting within the signal box was provided by a large pressurised oil lamp, suspended from the ceiling. The lifeboat-style fuel container and enamelled reflector ensured an even distribution of light. Despite advances in technology, Tilley lamps remained in use until the signal box’s final years before closure.
Above the instrument shelf, a framed signal box diagram was displayed. During the early BR(SR) period, this was Diagram No.191, which included details of the mechanical and electrical locking table. This was modified in 1952 following the replacement of treadle ‘B’ with track circuit ‘B’, and a portion of it can be seen in the 1957 interior photograph.
In December 1959, BR(WR) issued a new version of the diagram (S435), omitting the locking tables. This was updated again in early 1960 to reflect the abolition of signal 12, the Up Siding, and GF ‘B’. The post-1959 version of the diagram appears in the circa-1965/66 colour images.
The arm repeater for signal 12 was removed following the abolition of the signal on 28 February 1960. Later that year, a lamp repeater was installed for the replacement Down Advanced Starting signal (4). This was a wooden-cased BR(WR)-style indicator, positioned on top of the instrument shelf, between the Wellow block bell and the Block Telegraph instrument.
At an unknown date, a small round (possibly bakelite) toggle switch was added to the front of the instrument shelf, located above and between the arm repeater for signal 16 and the ‘Train Waiting’ indicator. While its exact function remains unclear, it is likely that it was installed to allow the signalman to cancel the warning buzzer associated with the ‘Train Waiting’ indicator.
Both the BR(WR) lamp repeater and the round toggle switch can be seen in colour photographs from circa 1965/66. Also visible in these images, beneath the window and behind the frame, are three large ratchet wheels, painted yellow or red, corresponding to signals 1, 15, and 16. These were used to adjust the signal wires and ensure proper tension for their operation.
Above the instrument shelf, a framed signal box diagram was displayed, providing an overview of Midford’s signalling layout. During the early BR(SR) period, this was Diagram No. 191, which included Mechanical and Electrical locking table details. This diagram was modified in 1952, following the replacement of treadle ‘B’ with track circuit ‘B’, and a portion of it can be seen in the 1957 interior photograph.
In December 1959, BR(WR) issued a new version of the diagram (S435), which followed their own style and omitted the locking tables. This version was further updated in early 1960 to reflect the abolition of signal 12, the Up Siding, and GF ‘B’. The post-1959 version of the diagram is visible in colour photographs from circa 1965/66.