Historical narratives of cartographic surveys conducted in nineteenthcentury Ireland and India have been well documented individually within the context of their own national formations and, albeit to a much lesser degree, in a comparative colonial light. Yet, while similarities and points of contact between Ireland and India in the formation of imperial geographical knowledge has often been recognised, relatively little scholarly work has been devoted to unearthing the interconnected history of cartography between these two countries. In recent years, there has been a growing body of work that has interrogated the relationship and influence between Ireland and India in terms of a critique of empire, literary influences, ideas of ‘internationalism’, and transnational histories of famine, to name but a few areas that have come under increased scrutiny. As Jill Bender observes, S.B. Cook's historical scholarship in this area set the stage for subsequent studies that would examine the ‘relations between Ireland and India in terms of a two-way traffic mediated through distinct but analogous experiences of British rule’. More recently, in Irish Imperial Networks, Barry Crosbie argues that one needs to further nuance the history of the Irish experience of empire (‘the multiplicity of communities’), as he writes: ‘To the detriment of empire studies in Ireland, nationalism during this period was generally equated with anti-imperialism and as a result the role that Ireland played in British overseas expansion was largely omitted from the Irish history books’. This lack of attention is all the more surprising given that ‘during the late eighteenth and early nineteenth centuries Irish scientific institutions and Irish people played an increasingly prominent role in Britain's attempts to expand the boundaries of empire eastward’. And, as Cóilín Parsons observes, ‘the historical fact of empire and the development of geographical knowledge and cartographic practices cannot be disaggregated’. It is argued here that British maps produced for state administration in this period (most notably with the Ordnance Survey in Ireland and the Great Trigonmetrical Survey in India) were very much embedded within a discourse coloured by scientific positivism, where the language of maps and science was seen to ‘faithfully’ and objectively depict the ‘real’ world.