Solution:The 1st Census in British India started in 1972 A.D. during the tenure of Lord Mayo (1869-72), but the regular census began in 1881 A.D. during the tenure of Lord Ripon.Richard Southwell Bourke 6th Earl of Mayo was a statesman from Ireland who held the position of Viceroy of India in from 1869 until his assassination in 1872. He was called Lord Mayo by the local Indians. Lord Mayo stabilised the northwestern frontier of India by cultivating closer relationships with Sher Ali, the emir of Afghanistan. He did this with the hope of negating Russian influence in the region and ensure a buffer state would exist between the Russian and British Empire. He ordered the first census of India in 1871 which produced a general picture of various peoples of the subcontinent and their population size. Setting up of Department of Revenue, Agriculture and Commerce. Introduction of the most improved rifle, the Snider, and of rifled guns for the artillery. Improvement in the sanitary conditions for the troops. Infrastructure development in the country by which an immense extension of roads, railroads, and canals was carried out.