It is a well-known fact that Pyrrhotite, or Magnetic Iron Pryrites, frequently, if not invariably, contains nickel, generally with cobalt in various proportions, amounting together from traces, up to nearly six per cent., and that most of the nickel of commerce is derived from this mineral

The following notes contain in the first place the results of the examination of a few varieties of pyrrhotite, occurring in Nova Scotia, New Brunswick, and the United States, chiefly with reference to presence or amount of nickel and cobalt, and they shew also that remarkable differences exist in the intensity of the magnetism displayed, which ranges from distinct polarity in the mass, down to very iceble attraction by a magnet in the finely powdered state of the mineral, and further, that the most feebly magnetic of the specimens examined is that containing the largest per centage of nickel. The subsequent notes relate to other species from h~ova Scotia and Newfoundland.