 In fact the initial six vessels were generally differentiated by a slightly lower speed and were often referred to as "26-knotters" to distinguish them from the following batch of thirty-six vessels; all fifteen surviving "27-knotter" vessels were classified by the Admiralty as the A class in 1913 to provide some system to the naming of HM destroyers.All of the "26-knotters" and most of the "27-knotters" had been lost or scrapped before the 1913 classification (and so - strictly speaking - never survived to become 'A' class), but for convenience all 42 ships are listed below.The number of funnels varied from one to four.