Further information from J Thickitt:

The grey vehicles in the foreground were called 'mineral waggons' which were loose-coupled, attached to each other by a short length of chain. They had been synonymous with coal traffic, with empties on return journeys. A train of mineral waggons could only be controlled by brakes on the locomotive and Brake Van, the latter attached to the end of the train (in this photograph an example was the taller, brown vehicle on the middle rake of waggons). Also known as a Guards Van, either name adequately described their purpose.

In this scene the brown-painted timber 'five-plank' waggons beside the brake were operated by the Permanent Way Department who were responsible for track maintenance. Possibly this location was a regular haunt for their vehicles, as in the 1960s and 1970s Mr Thickitt sometimes saw their trains stabled in sidings near Woodhouse station.

In the background an apparently empty 'Merry-go-Round'# train was passing. Introduced in 1965 and so-called because, eventually, there was no requirement for the train to stop either when loading coal at a pit nor discharging the load at a power station. During the 1960s and 1970s the pits to the south-east of Sheffield (thinking in particular of Thurcroft and Dinnington) also supplied coal to Trent-side power stations at Cottam and West Burton in Nottinghamshire.

Merry-go-Round vehicles carried the identification code HAA, identifying an air-braked hopper-waggon with automatic load-discharge. Note also one of the nearest mineral waggons carried the code ZHO; no doubt a relatively recent development by the date of this photograph.