Nautical chart great circle routes. NOAA uses the polyconic projection for some of its charts of the Great Lakes, at both large and small scales. Positions of places shown on the chart can be measured from the longitude and latitude scales on the borders of the chart, relative to a geodetic datum such as WGS 84. A bearing is the angle between the line joining the two points of interest and the line from one of the points to the north, such as a ship's course or a compass reading to a landmark. On nautical charts, the top of the chart is
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.