THE 



LONDON AND EDINBURGH 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



MARCH 1839. 



XXVII. On the general Magnetic Itelatio?is a7id Characters 

 of the Metals: Additional Facts. Bi/ Prof. Fakab ay. *^ 



A N idea that the metals would be all magnetic if made ex- 

 -'^^ tremely cold, as they are all non-magnetic if above a cer- 

 tain temperature, was put forth in March 1836tj and some 

 experiments were made, in which several were cooled as low as 

 — 60° or —70° Fahr., but without acquiring magnetic powers. 

 It was afterwards noticed X that Berthier had said that be- 

 sides iron, cobalt, and nickel, manganese also possesses magrietic 

 force beneath a certain degree of temperature^ much heloix) zero. 

 Having had last May the opportunity of working with 

 M. Thilorier's beautiful apparatus for giving both the liquid 

 and the solid state to carbonic acid gas, I was anxious to 

 ascertain what the extremely low temperature procurable by 

 its means would effect with regard to the magnetic powers of 

 metals and other substances, especially with relation to man- 

 ganese and cobalt ; and not having seen any account of similar 

 trials, I send the results to the Philosophical Magazine (if it 

 please the Editors to insert them) as an appendix to the two 

 former notices. 



The substances were cooled by immersion in the mixture 

 of ether and solid carbonic acid, and moved either by platina 

 wires attached to them, or by small wooden tongs, also cooled. 

 The temperature, according to Thilorier, would be about 112° 

 below 0° of Fahrenheit. The test of magnetic power was a 

 double astatic needle, each of the two constituent needles be- 



• Communicated by the Author. 

 t London and Edinb. Phil. Mag., vol. viii. p. 177. 

 J Ih'id., vol. ix. p. Ga. 

 Phil. Mail. S. 3. Vol. H. No. 88. Mar. 1839. M 



