Legacy cache, the train

Formerly known as LTS across Hadleigh Country Park
The London, Tilbury and Southend Railway (LT&SR) is a railway line linking Fenchurch Street railway station to Shoeburyness via Benfleet, it is 40 mi (64.37 km) long. A loop line serving Tilbury provides an alternative connection from London to Southend; and a branch line connecting the two via Chafford Hundred forms a third route. The line currently has a maximum speed limit of 75 mph, although the Class 357 Electrostar trains which run on it are capable of a maximum speed of 100 mph.
The London, Tilbury and Southend Railway ran from London along the River Thames to Tilbury and Southend. It was started operating in 1854 as a joint venture between the London and Blackwall Railway and the Eastern Counties Railway. Initially the line ran from Fenchurch Street and Bishopsgate Stations to Tilbury via Stratford, Barking and Grays, but in 1858 the service from Bishopsgate was withdrawn, with the line starting at Fenchurch Street and running through Barking, Plaistow and East Ham.
The line was extended to Southend by 1856 and to Shoeburyness in 1884. Between 1885 and 1888 a shorter route between Barking and Pitsea via Upminster was built, and between 1892 and 1893 a branch line was built from Romford to Grays via Upminster was built.
In 1912 the line was bought by Midland Railway (MR). In 1923 'the grouping' of the many small companies into one of four large companies resulted in the line becoming part of the London, Midland and Scottish Railway (LMSR).
Following the creation of British Rail in 1948 the line was nationalised and became part of British Rail's Eastern Region. In 1984 it became part of Network SouthEast. As a result of the privatisation of the railways following the Railways Act of 1993 LTS Rail was run by Prism Rail, before being bought by the ...current owners. The line was electrified in 1962.
The service was withdrawn from Bromley, Plaistow, Upton Park, East Ham, Becontree, Dagenham and Hornchurch Stations which were served by the District Line of London Underground. The trains thereafter ran faster through outer London calling only at Stepney East and Barking. The branch line between Romford and Upminster was also disconnected.
In 1974 a new station opened at Basildon, in 1995 at Chafford Hundred and in 1999 platforms were added at West Ham to provide an interchange with London Underground's new Jubilee Line extension.
You are looking for a white pot slightly smaller than a 35mm can, bring your own pen.