Parker, Field & Sons, London.
An entry from. Geoffrey Boothroyd's revised Directory.
John Field was the son-in-law of William Parker, his sons were John William Parker Field and William Shakespear Field. John Field Died in 1850 and the firm was run by his sons.
In business at 82 Tavistock street from 1822 to 1826 and then at 58 Mansell street from 1851 to 1881.
They are listed at 223 High Holborn from 1841 to 1876 then at 122 Leman Street from 1877 to 1878 moving to 59 Leman Street in 1879 until 1881.
They were granted a couple of registered designs no. 928 for a cartridge belt in 1847 and no. 3300 for a revolver rammer in 1852.