Eastern Counties Railway No. 154 Suffolk.

This engine was at first thought to have LNWR connections but has since been identified as Eastern Counties Railway No. 154 Suffolk, built by Braithwaite & Co in 1838 as an 0-4-0 and rebuilt by Kitson & Co in 6.1848 as an 0-4-2ST with a short chimney for working on the Woolwich branch and renumbered 188.
The ECR became part of the Great Eastern Railway in August 1862, and No. 188 was sold or scrapped in 1862-5. This photograph was reproduced in an early Locomotive Magazine.
The engine on the right seems to be one of Gooch’s 2-2-2WT of 1851-5, which were the first engines built at Stratford. There is a small photograph of one of them on page 90 of The British Steam Locomotive 1825-1925 by Ahrons, which seems to have been taken at the same place and time as that of No. 188.