MAGNETIC CHARACTERS OF METALS, &c. 627 
contribute to the progress of scientific knowledge, 
that I have ventured to offer it to the considera- 
tion of this Society. 
3. The superlative degree of magnetic action 
displayed by metallic iron, above that of all other 
known bodies, has beenatheme of almost continuous 
contemplation and philosophical speculation from 
remote periods in the history of science till the 
present day, and continues to be a subject of 
interest and admiration throughout every part of 
the scientific world. The ordinary laws of the 
magnetic action of metallic iron, especially when 
in masses, are, however, now so satisfactorily 
established, and the phenomena so well known, 
that any further notice of them in this place would 
be foreign to the object of this memoir; more 
especially as it alludes to the simple magnetic 
attractions only, whilst illustrating the novel 
facts it contains, and the mode by which they 
were developed. 
4. Nickel is a metallic body which, next to 
iron, stands most distinguished for the display of 
magnetic action: and, indeed, notwithstanding 
the number of inquiries that have been made re- 
specting the magnetic action of other bodies, and 
