Exp—The Mahalwari System was devised by Holt Mackenzie. In the North Western Provinces of the Bengal Presidency (most of this area is now in Uttar Pradesh), an Englishman called Holt Mackenzie devised the new system which came into effect in 1822.The collectors went from village to village, inspecting the land, measuring the fields, and recording the customs and rights of different groups. The estimated revenue of each plot within a village was added up to calculate the revenue that each village (mahal) had to pay.