What a pain in the arse that was... Knew it would be. To be honest I was in two minds whether to bother with it or not, so much rust is there anything worth saving under there?
Did what I could using only wet/dry paper and elbow grease so what could be achieved was very limited... It may be pitted but at least the pits are now shiny!
Anyway, it's a J. Beal & Sons of Sheffield, trademark "ENDURE" which was perhaps something of a family motto.
This particular trademark was only used between 1871-1876 so that's how old it is, not so bad considering I suppose. Interesting back story to this maker... The company was originally called J & J Beal Ltd. Their factory was Rand Moor Cutlery Works near Water Lane in Ranmoor. They began as scissor-makers in the 1790s. Peter Beal ran the factory and after his death in 1835 his widow Sarah and their son Joseph took over. A John Beal also entered the company - John died of typhus in 1846, shortly after in 1849 the company went bust and was in the hands of the Official Receiver who would have broken it up and sold it to pay creditors, but Sarah borrowed enough money to buy it back again, and the census return of 1851 shows her as being a scissor and razor maker.