28 DR. FARADAY’S EXPERIMENTAL RESEARCHES IN ELECTRICITY. (SERIES XX.) 
Sugar. 
Starch. 
Beef, dried. 
Blood, fresh. 
Blood, dried. 
Leather. 
Gum-arabic. 
Wood. 
Mutton, dried. 
Ivory. 
Apple. 
Bread. 
Beef, fresh. 
2281. It is curious to see such a list as this of bodies presenting on a sudden this 
remarkable property, and it is strange to find a piece of wood, or beef, or apple, obe- 
dient to or repelled by a magnet. If a man could be suspended, with sufficient deli- 
cacy, after the manner of Dufay, and placed in the magnetic field, he would point 
equatorially ; for all the substances of which he is formed, including the blood, pos- 
sess this property. 
2282. The setting equatorially depends upon the form of the body, and the diver- 
sity of form presented by the different substances in the list was very great ; still the 
general result, that elongation in one direction was sufficient to make them take up 
an equatorial position, was established. It was not difficult to perceive that compara- 
tively large masses would point as readily as small ones, because in larger masses 
more lines of magnetic force would bear in their action on the body, and this was 
proved to be the case. Neither was it long before it evidently appeared that the form 
of a plate or a ring was quite as good as that of a cylinder or a prism ; and in prac- 
tice it was found that plates and flat rings of wood, spermaceti, sulphur, &c., if 
suspended in the right direction, took up the equatorial position very well. If a plate 
or ring of heavy glass could be floated in water, so as to be free to move in every 
direction, and were in that condition subject to magnetic forces diminishing in inten- 
sity, it would immediately set itself equatorially, and if its centre coincided with the 
axis of magnetic power, would remain there ; but if its centre were out of this line, 
it would then, perhaps, gradually pass off from this axis in the plane of the equator, 
and go out from between the poles. 
2283. I do not find that division of the substance has any distinct influence on 
the effects. A piece of Iceland spar was observed, as to the degree of force with 
which it set equatorially ; it was then broken into six or eight fragments, put into a 
glass tube and tried again; as well as I could ascertain, the effect was the same. By a 
second operation, the calcareous spar was reduced into coarse particles ; afterwards 
to a coarse powder, and ultimately to a fine powder : being examined as to the equa- 
torial set each time, I could perceive no difference in the effect, until the very last, 
when I thought there might be a slight diminution of the tendency, but if so, it 
was almost insensible. I made the same experiment on silica with the same result, 
of no diminution of power. In reference to this point I may observe, that starch 
and other bodies in fine powder exhibited the effect very well. 
2284. It would require very nice experiments and great care to ascertain the 
