Diagram of the hurricane on the 3rd June 1839 reduced to half-scale from the
General Chart, outer circle 530 miles in diameter. Time, Noon. From: "The Law
of Storms in India" 1839-1842, by Henry Piddington. Calcutta, Bishop's
College Press. First Memoir, 1839. P. 584. This was one of the first diagrams
to show the circular shape and circulation of tropical cyclones.