Pen and ink and watercolour map by James Prinsep (1799-1840) of the area around the Machhodri tank at Varanasi (Benares) in Uttar Pradesh, dated between 1822 and 1829. The map contains cross sections showing the relative water levels of the marsh and the river, and the site of the proposed drain, and includes notes and measurements. Varanasi stands on the left bank of the Ganges and at its highest point stood well away from the river, but as the ground receded towards the water stagnant pools and marshes formed near the most densely inhabited areas during the rainy season and became a danger to health. Prinsep devised a plan to drain the city and built a network of drains and a tunnel which were considered a great feat of engineering. The sewers were opened in 1824 and the tunnel, in 1827. The Machhodri tank, drained by Prinsep, was formerly a marsh and later the site of a park and a grain market, the Bisheshwarganj, established in 1830. Prinsep came from a family who served in India for three generations; five of his brothers were also in the country. James, also a noted scholar and antiquarian, was Assistant Assay Master at the old Calcutta Mint in 1819, and after occupying the position at the Benares Mint from 1820-30 finally became Assay Master of the Calcutta Mint in 1832.