West prospective view of Portsmouth harbour. The National Gazetteer of 1868 reported 'Portsea Island, on which Portsmouth stands, is separated from the main land by a narrow inlet at its northern extremity. Portsmouth harbour, which is on the W. side of it, is entered by a narrow creek at the S., defended by Southsea Castle and Monckton Fort. The narrowest part is at Portsmouth Point, a little higher, where the width is only 220 yards. The basin of the harbour measures about 3 miles each way, and contains three channels, leading to Porchester, Fareham, and the N. of Portsea Island. The depth is sufficient to accommodate men-of-war of all sizes, even at low tide'. This original drawing is the basis for a later engraving entitled 'The West Prospect of Portsmouth, in Hampshire', made by Samuel and Nathaniel Buck on 11 September 1749.