The Stockton & Darlington Railway’s Coal Drops at Shildon

Introduction

Shildon (or at least that part of it known in 1825 as New Shildon) is the world’s earliest railway town (Jessop this volume). New Shildon lay 2 kilometres south of the original village, at the western end of the level section of the Company’s main line, i.e. that part over which steam locomotives were able to operate. (The line extended 7 kilometres to the north-west as far as Witton Park Colliery, but the gradients on this section were too steep for steam locomotion and were worked instead by a combination of horses and steam-powered rope-inclines ). Accordingly, New Shildon developed rapidly as both an engineering and service hub for the railway. By 1827, two more horse- and incline-powered colliery railways had converged on the town which subsequently became a major marshalling facility where coal wagons were organised into trains for the steam-hauled leg of their journey east to the company’s land depots (Jecock and Hardie this volume) and to staithes on the River Tees at Stockton and later Port Darlington (Middlesbrough) for wider export.

The Company constructed the so-called ‘Coal Drops’ at Shildon in late 1846/early 1847 (although evidence suggests they were rebuilt/reconfigured several times thereafter). Despite the name, the installation was a device for re-fuelling steam locomotives using gravity to drop coal into engine tenders, not, as is more commonly the case with ‘Drops’, for dropping coal into wagons pulled by those locomotives. The Drops were intended to speed up the turn-round time of locomotives returning empty wagons to the Shildon yard before departing with their next train. Historic England recorded and researched the extant structure in early 2020 as part of its Stockton & Darlington Railway Heritage Action Zone initiative.

Description of the standing fabric

As they survive, the Drops consist of an elevated platform or stage, some 6 metres high, approached from the north-west by a ramp. Both ramp and stage are retained by stone arcading composed of 49 narrow, blind, arched recesses which gradually and progressively increase in height and depth towards the eastern stage, where the rhythm of the arcading is broken at regular intervals by four rectangular ‘bays’, one much wider than the other three. Photographic evidence from the 1920s and 30s, taken only a few years before the Drops closed in 1935, shows that the three narrow bays were where the fuelling mechanisms were located although the actual timber ‘hoppers’ and ‘spouts’ that once stood here have long disappeared. The fourth, wider, bay contained a timber platform which may have been intended as a raised surface, close to tender-height, off which coal could be shovelled if, for whatever reason, a locomotive could not refuel at the gravity-fed spouts.

The Drops lie at the end of a former branch line running down from Black Boy Colliery to the north. Coal wagons hauled up the ramp, discharged their loads through bottom-opening doors into the hopper within each bay where coal was retained until needed by locomotives passing on the ‘coaling road’ below. Given the steep angle of the approach ramp (about 5 degrees or 1:11), it is perhaps unlikely that wagons coming from the colliery were hauled up onto the stage by locomotive. Instead, since the branch line was also too steep to be worked by locomotives and was rope-hauled, it may be that wagons were allowed to free-wheel the last part of the incline and climbed the ramp using their own momentum under the supervision of a ‘wagon-rider’ who judiciously applied the brakes at the correct moment.

There is evidence in the surviving stonework of the Drops for several phases of rebuilding and strengthening, including at least one phase of heightening. Strengthening work is manifested by the buttressing which visibly infills alternate arched recesses and represents a self-evidently successful attempt to stabilise the face of the stone ramp which at some point had started to settle and lean outwards. Early map evidence also points to the high-level stage initially being much shorter and approached by an earthen incline (indicated on the OS map by hachuring). However, the principle of using gravity feed to deliver coal to locomotives was present right from the start, as is demonstrated by references to the Drops immediately after construction as ‘hoppers’ and ‘self-filling spouts’.

Significance and parallels

In the decades immediately after 1825, the sole means of fuelling a locomotive - both on the S&DR and the nascent national UK rail network more generally - seems to have been by teams of men laboriously shovelling coal from lineside bunkers into the engine tender. However, our research at The National Archives uncovered a letter that suggests in October 1846 the S&DR was reviewing its procedures and had come up with a novel plan. It is unclear who exactly came up with the idea. Both men in charge at Shildon – the engineer William Bouch and the works manager Oswald Gilkes - seem to have doubted the need for the Drops, but the idea was supported by Joseph Pease, the Company manager. Designs subsequently drawn up by John Graham, the Traffic Superintendent, had been quickly approved by December; construction must have started soon after and was complete the following year.

Unfortunately, those first plans seem not to survive, and therefore detailed evidence for the original form of the hoppers and spouts is lacking. Indeed, the only evidence for what these features looked like or details on their operation consists of one newspaper report of a coroner’s inquest into a fatal accident in 1884 plus the few 20th-century photographs of the Drops in use.

Nevertheless, using these sources in combination with evidence in the stone fabric such as sockets where horizontal timber beams were once located, we have been able to reconstruct their final form. Their earlier form is unlikely to have been radically different. Wagons on the stage dropped their load of coal into timber hoppers positioned within the bays beneath, where it was retained by a trapdoor pending the arrival of a locomotive requiring fuel.

Once the locomotive had parked on the adjacent coaling road adjacent to a hopper, the fireman would clamber up into his tender, pull a lever to open the trapdoor and so allow the coal within to slide gently down a chute into the tender. 

As we have seen, what survives of the Drops today is not what was first built : they were demonstrably reconstructed and extended on occasion and their operation improved. But the general principle of how they functioned – utilising gravity to transfer coal directly between wagons and locomotive tenders without the need for manual shovelling – remained constant. In this, it is likely that whoever it was in the S&DR who first proposed the idea of the Drops in 1846 took inspiration from the coal drops that already existed - and had done for a century or more – at coastal coal staithes where they were used to transfer coal arriving by rail into sea-going vessels. These structures were designed to eliminate both the double-handling of coal and to permit gentle transfer (coal in large chunks burned better and was therefore worth more than small nuggets or dust). The coastal coal drops worked by positioning coal wagons with bottom-opening doors above chutes that guided the contents down into the ship’s hold or, alternatively, if the wagons had end doors, by lowering them into the hold on platforms and upending them.

Impact

The idea of taking an existing technology and putting it to novel use to refuel railway locomotives seems to have been an S&DR first - both nationally and, given the UK’s primacy in the development of railways, perhaps globally – but it was not one widely adopted by the S&DR’s competitors. For example, in 1851 the London & North Western Railway’s engineer, John Ramsbotham, came up with an alternative, some might say Heath Robinson, design for a canted rotating carousel of buckets.

The failure of the S&DR’s idea to be widely copied is likely because it was conditional on the design of coal wagon a company operated. Wagons at this time came in a multiplicity of types with a range of door positions (side-opening, end-opening, bottom-opening). Thus, unless the delivery of coal to a locomotive refuelling stage could be guaranteed to come always in bottom-opening wagons, other forms of coaling stage had to be developed. As it was, it was not until 1910 that the principle of gravity refuelling was adopted widely across the UK rail network, but this time it was the entire wagon that was upended into hoppers.

The Shildon Drops were already listed at Grade II prior to the HAZ, but following the research reported here that listing has been upgraded to II*. What at first sight seemed a very unassuming monument type, has been shown to be a major development in the way steam locomotives were refuelled on Britain’s early railways.

Further information

Jecock M, L, Stephens, G Young and M Bristow 2022 ‘Stockton and Darlington Railway Locomotive-Coaling Stage, Shildon, Co. Durham: Historic Building Investigation and Assessment of Significance’. Historic England Research Reports Series 75/2022.

Ramsbotham, J 1853 ‘Description of an Improved Coking Crane for Supplying Locomotive Engines’, Proc Institution of Mechanical Engineers, 7 122-5 and Plate 28.

Smith, GT 2019 A Railway History of New Shildon.

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