On interrupting the current the permanent magnetism will increase 

 a little, but will not regain its original intensity. Repeated trans- 

 mission of a current through the wire produces only a feeble dimi- 

 nution of its permanent magnetism. If a current be transmitted 

 through the wire in an opposite direction, the magnetism will again 

 be greatly enfeebled. 



7. When a large portion of the permanent magnetism has been 

 destroyed by repeated inversion of the current transmitted through 

 the wire, and a current is made to pass through it first in one direction 

 and then in the contrary direction, the magnetization in one case is 

 found to be much stronger than in the other. At the same time a 

 very gradual diminution of magnetism is continually observable. 



In the opinion of Professor Wiedemann, these phenomena may be 

 explained by the self-same hypotheses which he used to illustrate his 

 former observations on the relation between torsion and magnetism. 

 These are : 



1. The hypothesis of molecular magnets, which take a direction 

 under the influence of a voltaic current and are thereby caused to 

 rotate round their centres of gravity, and also to glide past one another, 

 as in the case of torsion. 



2. The hypothesis, that the molecular magnets, after their move- 

 ments of translation and rotation, do not return quite to their original 

 unmagnetic positions of equilibrium, even after the disturbing forces 

 have ceased to act, so that bodies composed of these molecular magnets 

 retain a permanent magnetism, and in certain cases, a permanent 

 change of form, viz. torsion. 



II. " Preliminary Notice of Researches into the Chemical Con- 

 stitution of Narcotine and of its Products of Decomposition." 

 By A. MATTHIESSEN, Esq., and GEORGE C. FOSTER, Esq. 

 Communicated by Professor A. W. WILLIAMSON, Ph.D. 

 Received October 29, 1860. 



I. Composition of Narcotine. 



The announcement made by Wertheim*and Hmterbergerfof the 

 probable existence of various kinds of narcotine, rendered it necessary 



* Liebig and Kopp's Jahresbericht, 1851, p. 469. f Ibid. 



