The island on which the city of Key West stands forms one of the links in a long, curving chain of shoals, reefs, and keys extending in a southwesterly direction about a hundred miles from the extreme end of the peninsula of Florida. It is approximately six miles long, has an average width of one mile, and resembles a little in shape a huge comma, with the city of Key West for its head and a diminishing curve of low, swampy chaparral and mangrove-bushes for a tail. The shallow bay of pale-green water between the head and the tail on the concave side of the comma is known as "the bight." It is the anchorage of the sponging-fleet, and is the eastern limit of settlement on that side of the island. Beyond it are sandy flats and shallow, salt-water lagoons, shut in by a dense growth of leather-leaved bushes and low, scrubby China-berry, sea-grape, and Jamaica-apple trees. The highest part of the Key is occupied by the city, and the highest part of the city is the low bluff on its western side, where the slender shaft of the lighthouse stands at a height of fifteen or eighteen feet above the level of tide-water. Owing to its geographical position in a semi-tropical sea, just north of the Gulf Stream and within the zone of the northeast trade-winds, Key West has a climate of remarkable mildness and equability. Twenty years' observations show that its lowest monthly mean of temperature is 70 deg. F. in January, and its highest 84 deg. in August--an annual range of only 14 deg.. Between the years 1886 and 1896 the highest temperature recorded was 92 deg., and the lowest 40 deg.--a range of only 52 deg. between maximum and minimum in a period of ten years. New York and Chicago often have a greater variation of temperature than this in the course of ten days.