18 DR. FARi^DAY’S EXPERIMENTAL RESEARCHES IN ELECTRICITY. (SERIES XXII.) 
ness. These, when suspended opposite one conical pole, proved to be perfectly dia- 
magnetic ; and when before it or between two poles strongly magnecrystallic. I have 
a pair of flat-faced poles with screw-holes in the centre of the faces, and these so 
much weaken the intensity of the lines of magnetic force about the middle of the 
field, when the faces are within half an inch of each other, that a cylinder of gra- 
nular bismuth 0'3 in length sets axially, or from pole to pole (2384.). But with 
the plates of arsenic between the same poles there was no tendency of this kind ; so 
much was the magnecrystallic force predominant over the diamagnetic force of the 
substance. 
2533. When the plates of arsenic were suspended with their planes horizontal, 
then they did not point at all between the flat-faced poles. Any inclination of the 
planes to the horizontal line produced pointing, with more or less force as the planes 
approached more or less to the vertical position, exactly in the manner already de- 
scribed in relation to bismuth and antimony (2482. 2518.). 
2534. Thus, arsenic with bismuth and antimony are found to possess the magne- 
crystallic force or condition. 
Royal Institution, 
September 23, 1848. 
