24 Mr. Charles L. Barnes on 



follows: "Si bonus sis, venias; si nequam, nequaquam." 

 "If you are a good man, you may come; if you are a bad 

 one (a Neckam), we won't have you at any price." 



He composed a Latin elegiac poem on science in ten 

 books, but his principal work is De Naturis Rerum, which 

 was written before the end of the 12th century. It 

 includes an account of the Creation, and dissertations on 

 the four elements, on astronomy, natural history, and on 

 minerals. The earliest recorded mention of the man in the 

 moon occurs here, though only as a tradition ; the marks 

 on its surface are ascribed to caves, hills, and valleys. 

 His remarks on Magnetism are worth quoting, as he is 

 the first English writer who mentions this subject. After 

 explaining the hanging of Mahomet's coffin by this means, 

 he continues: "The sailors, moreover, as they sail over 

 the sea, when in cloudy weather they can no longer profit 

 by the light of the sun, and when the world is wrapped up 

 in the darkness of the shades of night, and they are 

 ignorant to what point of the compass their ship's course 

 is directed, they touch the magnet with a needle, which is 

 whirled round until, when its motion ceases, its point 

 looks direct towards the north." In another treatise, 

 De Utilitensibus, also of the 12th century, he has another 

 mention of the compass, and says that "among the stores 

 of a ship there must be a needle mounted on a pivot, 

 which will oscillate and turn till the point looks towards 

 the north." The pivot is a distinct advance over a needle 

 floating on a straw. In view of the interest attaching to 

 early references to the compass, I may quote the following 

 extracts, given for the sake of reference, in the same 

 volume. Cardinal Jacques de Vitry, Bishop of Aeon, in 

 Palestine, in a History of Jerusalem, written about 1218, 

 says: "An iron needle, after having been in contact with 

 the loadstone, turns itself always towards the north, which, 

 like the axis of the firmament, remains immovable, while 



