Correspondence with tradesmen, including letters from booksellers; coal merchants; clock repairers; horologists; builders; chandlers; merchants; instrument makers; opticians; stationers; chemists; journeymen; photographic suppliers; decorators; bookbinders; shipping agents; glass manufacturers; the Post Office; gas engineers; electricians; furniture removers; the India Rubber, Gutta Percha and Telegraph Works Company; a grocer; a newspaper; and the South Metropolitan Gas Company. The letters cover various instructions; requests; accounts; invoices; bills; receipts; tenders; circulars; routine repairs; and adjustments and improvements to instruments. There are also notes by W.H.M. Christie.