Mile
2 of the 7 encyclopedias on this shelf carry an entry for Mile. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a measure of distance. Mile is from the Latin mille, a thousand, and means literally a thousand steps or paces. It became a legal English measure of distance during the reign of Queen Elizabeth. A legal mile is 5,280 feet in length. A square mile contains 640 acres. The ancient Scottish mile equaled 1,976 yards or 1.123 English miles. The Irish mile equaled 2,240 yards or 1.273 English miles. The Welsh mile was nearly four English miles in length. The term has been used variously in the countries of continental Europe. The greatest mile is that of Saxony which equals 9,062 metres; the least being that of Greece, a mountainous country, which equals 1,292 metres. The geographical or nautical mile or knot defined by the United States Coast Survey is the one-sixtieth part of the length of the degree on a great circle , or 6,080.27 feet.
Collier's New Encyclopedia (1921)
a measure of length or distance in use in the United States and almost all European countries. The English statute mile, in use in the United States, contains 8 furlongs, of 320 poles, or 1,760 yards or 5,280 feet; in surveying it measures 80 chains. A geographical mile is 6,075 feet (nearly), or 1.15 statute miles. A square mile is 6,400 square chains, or 640 acres. The English statute mile = 1,609.3148 French mètres. A league is 3 miles. The nautical mile is 2,028 yards, or 1,014 fathoms. The Irish mile is 2,240 yards, or 1.273 English mile. The German short mile is = 3.897 English miles. The German long mile = 5.753 English miles. See METRIC SYSTEM.