[Letter] 1825 Mar, Buckingham Street, Fitzroy Square, London [to] Charles Macintosh/W.H. Wollaston. [Hastily written in reply to urgent request for an opinion on Macintosh's steel samples. Urges immediate patent application. Postscript describes Macintosh's distillation of coal tar as being better than "laborious condensation of peat" and advises him on methods of reducing iron oxides. Accompanied by typed transcript [19--] of part of the letter also giving some background information.]