Introduction

Corfe Mullen Junction (CMJ) was located at the southern end of the 'main line' of the Somerset & Dorset Joint Railway (S&DJR), at the divergence of the routes to Wimborne and Broadstone (both of which were on the line of the London & South Western Railway from Southampton to Dorchester via Ringwood). Apart from a level-crossing, crossing-keeper's house and signal-box this location was simply a railway junction, without any passenger or goods facilities. For some years there was a small Corfe Mullen Halt located about a mile south of CMJ on the line to Broadstone, but this halt was not opened until 1928 and was closed in 1956.

The southern part of the S&DJR had been constructed originally by the Dorset Central Railway (DCR) as a single-track line running northwards from Wimborne Junction to Blandford. The first station north of Wimborne was at Bailey Gate and between those two stations there were three manned level-crossings:- Lake Crossing, Corfe Mullen Crossing and Bailey Gate Crossing. All three crossings were provided with resident crossing-keepers and some form of signalling, although only the latter two are believed to have had actual gate boxes. Bailey Gate station itself was originally the first block-post and passing-loop up the DCR line from Wimborne Junction. Sadly there are no known details available about the original gate-box at Corfe Mullen.

The New 'Cut-Off' Line

S&DJR trains originally had to reverse at Wimborne in order to run over the L&SWR to Bournemouth, which became an increasing hindrance with the growth in through traffic from Bath and the North to the south coast. To ease this problem a new "cut-off" line was constructed, which left the S&DJR route at Corfe Mullen (just south of the level-crossing) and ran south-eastwards to rejoin the L&SWR at Broadstone Junction. Known officially as the ''Poole & Broadstone Junction Railway", it was brought into use for goods traffic in December 1885 and for passenger traffic in November the following year. Although the actual divergence from the original DCR route was at Corfe Mullen there was no physical junction there at that time - instead the Wimborne and Broadstone lines continued northwards as parallel single-lines as far as Bailey Gate station, where the actual junction was made. Consequently the gate boxes at Corfe Mullen and Bailey Gate level-crossings now controlled two parallel single-lines. The new line was the first section of the S&DJR to be worked by the Electric Train Tablet (ETT) method.

New Signal-Box and Junction

The use of two parallel single-lines came to an end in 1905, when a physical junction between the 'old' and 'new' lines was constructed at Corfe Mullen and a new CORFE MULLEN JUNCTION signal-box (CMJ) was opened to replace the original gate box. The new signal-box was a S&DJR TYPE 3 (similar to the L&SWR TYPE 4) brick box with a gable roof, containing a 24-lever frame of the Stevens 4.1/8" centres pattern and a gate-wheel. The signal-box was opened on 16-April-1905 and it was inspected for the Board of Trade by Major Pringle on 29-June-1905. The original junction at Bailey Gate (BG) was removed and henceforth the line from BG to CMJ was worked as ordinary double-track and controlled by standard S&DJR block telegraph, while the two single-lines from CMJ to Broadstone Junction and Wimborne Junction were worked by Tyers No1 ETT.

1905 Signal Diagram
Click diagram for larger image (69KB)

The Up Starting signal (No 17) was located a short distance north of overbridge No 221 and consequently was on a short post to aid sighting under the bridge. Photographs taken circa-1912 show that at that time it was on a post of the unique S&D rail-built type. During World War I some alterations at Bailey Gate Crossing (BGC) meant that BGC's Up Home signal had to be moved some distance further south towards CMJ, after which it was slotted to act also as CMJ's Up Starting signal and the existing CMJ Up Starting was removed. At the same time (1915) BGC was upgraded to block-post status, although subsequently it was down-graded again in 1923.

Bridge Indicators

One feature of CMJ which remains as one of the great mysteries of S&DJR signalling was the provision of two 'bridge indicators' (15 and 16), which were fixed one each to underbridges on the Wimborne and Broadstone single lines some distance in the rear of the respective Up Home signals. The purpose of these indicators is unknown and no other examples are known on the S&DJR, yet they are not mentioned specifically in the 1905 Inspection Report nor in any other S&DJR records. The manner in which these arms are depicted on the original signal-box diagram indicates that they were pivoted or swivelled in their centre and were fixed to the outside or underneath of the bridge, suggesting that their function was directed at the road traffic rather than the railway. It is curious that, according to the contemporary locking-table, both levers 15 and 16 had to be reversed in order to release any of the Up or Down Home signals (2, 4, 18 or 20) - i.e. the passage of a train to/from either single-line required an action affecting the other.

The bridge indicators were fixed to two bridges over the same minor road, which ran between the two lines at a point where they were on embankments within 100 yards of each other. It has been suggested that there may have been some (real or imagined) problem with horses being startled if they were on the road in the 'canyon' between the two lines when a train was passing, so the indicators might have been used to give a warning of the approach of trains. Why this should be necessary at CMJ especially is unclear, particularly as the interlocking did not preclude the fact that a Up train could approach on either line with the relevant Up Home signal 'on' and the indicator might not be reversed until after the train had passed. It is not known if the provision of the indicators coincided with the 1905 new box, nor when they were removed - certainly they did not exist after the 1933 alterations, but as their removal was not mentioned specifically at that time they may have gone at an earlier date.

Corfe Mullen Siding

About three-quarters of a mile down the 'old line' to Wimborne was Corfe Mullen Siding, known generally as "Carter's Siding", which was opened in 1903 to serve a small clay works. This siding was on the Up side of the line and accessed by a connection facing to Up trains, being controlled by a 4-lever covered ground-frame unlocked by the tablet for the single-line section. Although only a minor feature of the local railway scene, in due course this siding assumed a greater significance in the future shape of the S&DJR in the area when it played a part in shaping the subsequent alterations which took place upon closure of the 'old road' in 1933.
		Siding GF Diagram Click diagram for larger image (20KB)

Corfe Mullen Halt

Corfe Mullen Halt was situated on the 'cut-off' line to Broadstone. It was a simple, short platform located on the Up side of the line immediately to the south of overbridge 235. It was opened on 5-July-1928 for passenger traffic only and was closed on 19-September-1956. There have been suggestions that some form of siding also existed at one time just to the north of the halt for the purposes of loading ballast wagons, but there is no evidence for this other than the existence of a possible loading bank, which may have been served simply by trains standing on the main running line.

Economies

With the passage of time the traffic over the 'cut off' increased to such an extent that the ex-DCR line to Wimborne in effect was relegated to branch status, carrying only local traffic. In due course the traffic dropped to such a level that consideration was given to the complete closure of the line from CMJ to Wimborne Junction. Plans were prepared also for the doubling of the section from CMJ to Broadstone Junction which, coupled with the proposed closure of the level crossing at CMJ (by diverting the minor road to a nearby overbridge), would have enabled the abolition of CMJ box. At the same time it was proposed to eliminate Bailey Gate level crossing by replacing it with an overbridge and the result of all these works would have been the closure of three signal-boxes and two gate-boxes. However the proposals for the alterations on the main line never came to fruition and so the boxes at CMJ and BGC remained in use, although BGC itself was downgraded to ground-frame status in 1923.

Passenger traffic eventually ceased between CMJ and Wimborne on 11-July-1920, but goods traffic continued until 17-June-1933. Proposals for complete closure of the 'old' line were complicated by the need to continue to handle the traffic from Carter's siding. The initial suggestion was to retain the line from that siding into Wimborne, with the connection at Wimborne Junction being worked by a ground-frame - although this meant that in fact most of the 'old' route would have remained in use after all, presumably the low level of traffic would have reduced the maintenance costs. In fact the solution chosen eventually was the exact opposite and the 'old' line was closed completely from Carter's Siding to Wimborne Junction, with only the short length from CMJ to Carter's Siding being retained. This arrangement enabled the ex-L&SWR signal-box at Wimborne Junction to be closed (the S&DJR box had closed a few years earlier and its work passed to the L&SWR box) and also abolished Lake Crossing, which had been reduced previously to traincrew-operated status.

Junction Alterations 1933

Following the closure of the 'old line' to Wimborne on 18-June-1933 the layout at CMJ was simplified to become merely the end-on junction of the double-track line to the north with the single-track to the south. Block working to Bailey Gate and Broadstone remained unchanged. The 'old line' was terminated just short of Lake Crossing and the remnant was worked now simply as a long Down Siding, accessed by a facing connection off the Down Main. A ring was added to the arm of the former "To Wimborne" Down Home signal (2) to denote entry to a goods line. The ground-frame at Carter's Siding was removed and thereafter its points were worked by hand-lever.

1933 Signal Diagram
Click diagram for larger image (54KB)

Under the revised arrangements Carter's Siding was worked by Down trains, which drew their wagons to the siding and then propelled back to CMJ upon completion of shunting work. On return to CMJ the train had to be pushed 'wrong road' back onto the Down Main in order to clear the Down Siding, so a 'Limit of Shunt' board was erected to control this movement 300 yards in rear of the Down Homes on the outside of the Down Main. The curvature of the approach to CMJ along the Down Siding gave inadequate sighting of ground signal 13 (which controlled the exit from the siding), so a repeater signal 13R was provided 190 yards in the rear. This repeater was of the 'miniature semaphore' type with a yellow arm, so that the returning train could pass it in the 'on' position.

Later Changes

After 1933 the arrangements at CMJ remained generally unchanged, apart from a few minor alterations. The Up Home (20) (and the lower Up Distant for Bailey Gate Crossing) had remained on a remnant of the bracket that originally had also carried the Up Home for the 'old road', but on 11-September-1938 this bracket was replaced by an ordinary straight post 60 yards in the rear. At some unknown date the Siding Home (2) seems to have lost its ring, possibly when the arm were converted to upper-quadrant (UQ) (sometime in BR days?). The Down Distant (3) was converted to UQ in 1953 and the Up Starting (17) in 1957. In early British Railways days the Tyers No 1 ETT instrument for the single-line section to Broadstone was replaced by the No 6 pattern pattern (click to see tablet). The Down Siding was taken out of use on 19-September-1959, although at least part of it seems to have remained in place for wagon storage - there are no details known about the cessation of traffic from Carter's Siding.

Closure

On 7-March-1966 passenger services ceased on the whole of the S&DJR and most of the line was closed, but a few sections remained open for goods traffic and this included the line from Broadstone as far north as Blandford. The line from CMJ to Blandford remained as double-track initially, but eventually the Up line was taken out of use and traffic was worked in both directions over the Down line. CMJ was reduced to GF status on 25-July-1966, after which it appears to have worked only the gates with the signals being disconnected, and it was closed completely on 7-May-1968. The line itself was closed finally on 6-January-1969. The former crossing-keeper's house remains in use today as a private residence.

© CJL Osment 2001

Interested in the Somerset & Dorset Joint Railway?
Then why not join the Somerset & Dorset Railway Trust
and help to keep alive the memory of this famous line?