Sir: J Michael Sharman (letter, 5 January) asks about the origin of alphabetical order. In his book The White Goddess, Robert Graves explains that alphabetical order derives from the ancient Celtic alphabet, where letters were named after trees and put into the order in which the trees flowered throughout the year.
Tree names were also used to represent numbers, days of the week, and concepts such as life and death. The yew tree represented death and is still grown in cemeteries.
Mrs CHARMIAN HAYES