Today’s episode brought to you by my audio-book Global Wording - The Fascinating Story of the Evolution of English . Available in downloadable form from iTunes or Audible.com or as a CD from bookstores. For more information and a few samples, go to www.globalwording.com Like a belt around the belly of a very fat man the equator runs around the middle of our planet earth.  To the north of the equator is the northern hemisphere, to the south the southern hemisphere. The equator divides the world into two equal halves and although the word equator literally means something that makes things equal, such as halves of a planet, it is not this particular equalization that gave the equator its name. It was Geoffrey Chaucer in approximately 1391 who put pen to paper and scribbled out the word equator for the first time in English. This was not as part of one of his Canterbury Tales , but instead, it is believed, a piece he wrote for the son of a friend.  The piece is entitled A Treatise on the Astrolabe and is dedicated to Little Lewis. For a while it was assumed that Little Lewis was Chaucer’s own son.  In fact that’s how the work was republished when Walter Skeat, the great etymologist gave it a close going over back in 1872. But researchers now think Little Lewis was Lewis Clifford and that poor Lewis passed away before the treatise was complete, explaining why Chaucer never finished the thing. What the thing was is now believed by some to be the oldest known “technical manual” in English. An astrolabe is a kind of tool used by ancient sailors, mapmakers and astronomers.  With an astrolabe you could figure out based on the time of day and the position of the sun or stars where you were on the globe. So this work of Chaucer’s wasn’t a story like his more famous Canterbury Tales, it was a practical instruction manual for Lewis’ further edification. You can see that an instruction manual for such a practical navigational tool would logically refer to the equator from time to time. But that doesn’t tell you why the equator is called the equator . The reason is due to a natural phenomenon observed much earlier than Chaucer. In fact our term equator is actually a contraction of a whole Latin phrase circulus aequator diei et noctis or in modern English “the circle that makes day and night equal.” You see, we in the northern hemisphere have longer days in summer and shorter days in winter since the world is tilted in respect to its orbit around the sun. In Australia and such places when we are tanning, they are flicking on the light switch. But those places that lie along the earth’s equator have 12 hours of day and 12 hours of night all the time. There is no winter or summer for them.  They are on the circle that makes equal day and night, the equator. Less