'Dan O’Callaghan Sahib, the doctor of the arsenal of the Delhi troops. The date of the victory, twentieth of the month of September, corresponding to the first of the month of Safar,  the Christian year 1857'
This gun was most probably produced in India by one of the local English gunmakers installed there, the most well known being John Manton. The inscription, which mentions a Dr Dan O'Callaghan, must refer to someone of that name who published a work on the Indian Mutiny: "O’Callaghan was the Surgeon of the iith N.I., one of the regiments at Meerut ... and it is to be sup-posed that these figures were obtained by enquiry from the Adjutants of the regiments concerned soon after the outbreak." D. O’Callaghan, Scattered Chapters on the Indian Mutiny:The Fatal Falter at Meerut, Calcutta, 1861., p.3. Presumably after the Mutiny in 1858 he was positioned in Delhi.
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