42 C O N T E X T 1 3 1 : S E P T E M B E R 2 0 1 3 barrels were not replaced simultaneously was perhaps due to cost, but the eastern barrel may also have been in a worse state than the west, as the eastern side of the station building had structural deficiencies from the outset. While thewestern range buildings (booking hall,waiting rooms and offices) adequately supported the west barrel, the weight of the roof caused problems on the station’s eastern side, where support came only from the narrow cab run, originally a single-storey structure.This enduring problem was recognised and the cab run strengthened when a large inverted brick arch was added below the north entrance, recorded by MOLA in 2009. The replacement east barrel of 1869 mimicked the timber original, with plate-riveted, wrought-iron ribs supported by the original cast iron spandrels.The design was similar to the iron roof at GNR’s 1854 Bradford station (demolished in 1976).Ventilationwas incorporated into the new design, with an open-sided clerestory and horizontal line of horse-shoe vents, iron loops within a gap below the glazed area of the roof. The construction contractor was John Jay (1805–72), a prolific railway contractor and Cubitt’s original station builder in 1852.He also constructed part of GNR’s goods yard to the north (c1851). Established engineers and ship builders Westwood Baillie supplied the iron work. The roof was accessed from below by temporary timber staging, built on wheeled trestles running on the track rails, allowing work to progress along the roof as passenger locomotives passed below.After work was completed, the parts of the staging were numbered, dismantled, stored and used again 18 years later in 1887 when the timber ribs of the west barrel were also replaced with wrought iron. The leather-bound, handwritten contract, dated 3August 1886, between GNR and builders Andrew Handyside, held at the National Archives, gives the specification and details for the removal of the old western barrel roof and the construction of new roof ribs, including instructions to reuse the movable staging. The area known as the bomb gap, looking south west from platform 8. An original spandrel from 1852 is on the left and its 1948 replacement is on the right. Far right: By comparison, the clerestory of the west barrel of 1887 looking north. Note how the lattice purlins run over the top of the iron rib, raising the clerestory higher and giving a steeper pitch. The clerestory of the east barrel of 1869, looking north. Note the lattice purlins fixed to the face of the iron rib. During the recent works a movable staging was reemployed, though modern scaffolding replaced timber, and instead of running on train tracks it was suspended from and supported by the station structure.The requirement to keep trains running beneath as work gradually progressed along the roof was the same. Curiously the 1869 east barrel and the west barrel of 1887 are different in design. Lattice purlins were attached to the face of the ribs in the 1869 roof, while those of the 1887 roof ran over the top of the ribs, a less stable arrangement than the earlier scheme, being prone to lateral movement.An article by RMBancroft in the 1887 Transactions of the Society of Engineers explains that the clerestory of the earlier eastern roof had an angle of eight degrees at the pitch. As this had become grimy, in 1887 the height of the western barrel clerestory was raised by positioning the lattice purlins over the ribs, giving a steeper angled pitch of 20 degrees, despite the reduced stability, so that it might be kept clean with the flow of rain water. No major changes were made to the roof until 1941, when the station was hit by a Luftwaffe bomb which killed 12 people and brought down three bays of the western roof barrel, destroying part of the western range and severely damaging the booking hall. Temporary booking and refreshment facilities were quickly organised,
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