132 PHILOSOPHICAL TRANSACTIONS. [aNNO 1751, 



inch broad, and Vt of an inch thick, with two pieces of iron, each half the 

 length of one of the bars, but of the same breadth and thickness ; and 6 of hard 

 steel, each 54- inches long, half an inch broad, and -J^ of an inch thick, with 2 

 pieces of iron of half the length, but the whole breadth and thickness of one of 

 the hard bars : and let all the bars be marked with a line quite round them at 

 one end. 



Then take an iron poker and tongs, or 2 bars of iron, fig. 2, pi. 3, the larger 

 they are, and the longer they have been used, the better ; and fixing the poker 

 upright between the knees, hold to it near the top one of the soft bars, having 

 its marked end downward, by a piece of sewing silk, which must be pulled 

 tight with the left hand, that the bar may not slide : then grasping the tongs 

 with the right hand a little below the middle, and holding them nearly in a ver- 

 tical position, let the bar be stroked by the lower end, from the bottom to the 

 top, about 10 times on each side, which will give it a magnetic power sufficient 

 to lift a small key at the marked end : which end, if the bar was suspended on a 

 point, would turn toward the north, and is therefore called the north pole, and 

 the unmarked end is, for the same reason, called the south pole of the bar. 



Four of the soft bars being impregnated after this manner, lay the other two, 

 (fig. 3) parallel to each other, at the distance of about one-fourth of an inch, 

 between the two pieces of iron belonging to them, a north and a south pole 

 against each piece of iron : then take 2 of the 4 bars already made magnetical, 



he articled himself for i years as an assistant to Mr. Watkins, master of the academy in Spital-square : 

 on the expiration of which period, in 1742, he was taken into partnership with that gentleman, 

 whom he afterwards succeeded in the school, and there continued till the time of his death, in 1772, 

 In the 54th year of his age. 



Mr. C. being a man of very genteel and modest behaviour, he gained the respect and acquaintance 

 of the most eminent philosophers of his time ; with whom he ardently entered on the pursuit and 

 improvements of the then fashionable topics in philosophy ; as electricity, magnetism, lightning, 

 &c. in many branches of which he made considerable improvements and discoveries. In 17-1-9 he 

 was engaged, with his friend Mr. Robins, and Mr. Ellicot, in making experiments on the height to 

 which rockets can ascend, and the distance at which their light can be seen. His paper above 

 printed, on making artificial magnets, procured his election as a fellow of the a. s. and the present 

 of their gold medal : and the same year he was complimented with the degree of m. a. by the 

 university of Aberdeen. And in 1751 he was chosen one of the council of the r. s. an honour 

 which was twice repeated afterwards. In 1752 he, first of any person in England, verified Dr. 

 Franklin's hypothesis of the similarity of electricity and lightning, by drawing electric fire from the 

 clouds during a thunder storm. Next year also he communicated to the r. s. another discovery of 

 this kind, viz. the negative and positive states of electricity among the clouds; a discovery also just 

 made in America by Dr. Franklin. In 1 762 Mr. C. communicated his curious experiments on the 

 compressibility of water; for which he was a 2d time honoured with ttie r. s.'s gold medal. Num- 

 berless other ingenious papers were written by Mr. C. and published in the Philos. Trans, as well as 

 several other periodical works : a particular account of which, and many other circumstances in Mr. 

 Canton's life, may be seen in Dr. Hutton's Dictionary of Philosophy and Mathematics, 



