Surely, in this life, nothing! The student who endeavours to govern his faith by the methods of science asks no more of any ghost that ever walked the earth, than that it will prove itself a reality. Man loves the marvellous. The marvels of science, however, do not melt away into thin air on close examination. They thrive under the severest tests, and grow more and more extraordinary the more they are tried. The spectroscope and the radiometer are more wonderful than any 'supernatural' thing yet heard of. Transportation through the air in the arms of a spirit is a clear impossibility; but it is less wonderful than the every-day feats of electricity in our time, the bare conception of which would have filled Plato and Aristotle with awe.