The Last posted address for Forsyth as a Gunmaker was;
Alex Forsyth and Co; 8,Leicester Street,London.1850-1852.
Your gun was made in Birmingham circa 1880-1900 and has no direct connection with Alex Forsyth.
Most likely Thos; Forsyth was an Ironmonger[Hardware store]located in London. Ironmongers in this era often sold guns bearing their name. To accomplish this orders were placed with the Birmingham trade ,with specific instructions regarding the engraving/application of the sellers name.
One other possibility exists in that certain nefarious members of the Birmingham trade sold spurious guns bearing the name or part thereof of defunct famous makers for example Egg or in your case Forsyth.
W.W.Greener in his book ,The Gun, page 415 details the extent of the trade in guns bearing spurious names.

Last edited by Roy Hebbes; 03/25/15 08:15 PM.

Roy Hebbes