MAGNECRYSTALLIC CONDITION OF SULPHATE OF IRON, ETC. 
21 
in part, if not altogether, due to the magnecrystallic state of the substance ; but I 
do not think the evidence was quite conclusive. 
2542. Iridium and Osmium alloy. — The native grains of iridium and osmium are 
often flat, presenting two planes looking like crystal planes, which are parallel to 
each other even when the grains are thick. Some of the largest and most crystalline 
were selected, and, after ignition with flux and digestion in nitromuriatic acid, were 
examined at the magnet. Some were more magnetic than others, being attracted ; 
others were very little magnetic : the latter were selected and examined more carefully. 
These all pointed with great readiness and force, comparatively speaking ; for they 
were not above one-fifteenth of an inch long, and yet they set freely when the mag- 
netic poles were three or four inches apart. The faces of the crystalline particles 
were always towards the poles, and their length consequently not in but across the 
axial line ; and this was true whether the distance between the poles was small or 
great, or whether flat-faced or conical poles were used. I believe they were magne- 
crystallic. 
2543. Fusible metal. — Crystals of fusible metal (24570 pointed, but the crystals, 
which were apparently quadrangular plates or prisms, were not good, and the 
evidence not clear and distinct. 
2544. Wires. — I thought it possible that thin wires, which by the action of acids 
exhibited fibrous arrangements, might have their particles in a state approaching to 
the crystalline condition, and therefore submitted bundles of platinum, copper, and 
tin wire to the action of the magnet ; but no indications of magnecrystallic action 
appeared. 
2545. I submitted several metallic compounds to the power of the magnet, applied 
so as to develope any indication of the magnecrystallic phenomena. Galena, native 
cinnabar, oxide of tin, sulphuret of tin, native red oxide of copper, Brookite or oxide 
of titanium, iron pyrites, and also diamond, fluor spar, rock-salt and boracite, being 
all well-crystallized and diamagnetic, presented no evidence of the magnecrystallic 
force. Native and well -crystallized sulphuret of copper, sulphuret of zinc, cobalt 
glance and leucites were magnetic. Arsenical iron, specular iron and magnetic oxide 
of iron were still more so. I could not in any of them distinguish any magnetic 
results due to crystallization. 
2546. On examining magnetic salts, several of them presented very striking mag- 
necrystallic phenomena. Thus, with sulphate of iron, the first crystal which J 
employed was suspended with the magnecrystallic axis vertical, and it presented no 
particular appearances ; only the longest horizontal direction went into the magnetic- 
axis pointing feebly. But on turning the piece 90° (2470.), instantly it pointed with 
much force, and the greatest length went equatorially. The crystal was compounded 
of superposed flat crystals or plates, and the magnecrystallic axis went directly across 
these ; it was easy, therefore, after one or two experiments, to tell beforehand how the 
crystal should be suspended, and how it would point. Whether the crystals were 
