The individual calamity was, as you say, entirely unanticipated; but analogous misfortunes had been long a subject of discussion with astronomers. I need scarce tell you, my friend, that, even when you left us, men had agreed to understand those passages in the most holy writings which speak of the final destruction of all things by fire as having reference to the orb of the earth alone, But in regard to the immediate agency of the ruin, speculation had been at fault from that epoch in astronomical knowledge in which the comets were divested of the terrors of flame. The very moderate density of these bodies had been well established. They had been observed to pass among the satellites of Jupiter without bringing about any sensible alteration either in the masses or in the orbits of these secondary planets. We had long regarded the wanderers as vapory creations of inconceivable tenuity, and as altogether incapable of doing injury to our substantial globe, even in the event of contact. But contact was not in any degree dreaded; for the elements of all the comets were accurately known. That among them we should look for the agency of the threatened fiery destruction had been for many years considered an inadmissible idea. But wonders and wild fancies had been of late days strangely rife among mankind; and, although it was only with a few of the ignorant that actual apprehension prevailed, upon the announcement by astronomers of a new comet, yet this announcement was generally received with I know not what of agitation and mistrust.