Longitude by chronometer highest point, diminish the accuracy of determining longitude by chronometer as a method of celestial navigation. Accuracies of less than error in position are difficult to achieve using the "longitude by chronometer" method. Other celestial navigation methods involving more extensive use of both the Nautical Almanac and sight reduction tables are used by navigators to achieve accuracies of one nautical mile (1.9 km) or less. This only calculates a longitude at the assumed latitude though a position line can be drawn. The observer is somewhere along the position line. Time sight is a general method for determining longitude by celestial
How Many Miles to Babylon? good and your spurs be bright. How mony men have ye? Mae nor ye daur come and see.</poem> Various places have replaced Babylon in the rhyme, including London town, Barberry and Berry Bright. The rhyme was not recorded until the nineteenth century, but the reference to Cantelon in the Scottish version has led some to conclude that it refers to Caledon in the time of the Crusades. Babylon may be a corruption of 'Babyland', but the city was a common allusion particularly in seventeenth-century England and 'Can I get there by candlelight?' was a common saying in the sixteenth century.