“Our survey of the question produces one impression, and that very forcibly, viz.: that this narrow ridge of separation is ephemeral, that it is perishable, that under the tests or against the shocks of earth strains, it will succumb, and”--the lecturer raised his voice, half turned deferentially to the chairman, Dr. Smith, who accepted the attention with an assenting nod--“again the waters of the two oceans will unite, and the impetuous violence of the rushing oceanic river, the Gulf Stream, that now races and boils through the Caribbean Sea, will fling its torrential waves across this divide into the Pacific.” The audience that with manifest absorption had thus far followed the speaker, was disturbed. A movement of chairs, a half audible protest of whispered incredulity, and a sensible emanation around him, of mental repugnance to such a catastrophe, made Leacraft momentarily turn his eyes from Mr. Binn to the frowning countenances at his side. “But,” the speaker raised his voice with reassuring quickness, as if to stay the emotional resistance he had aroused, “we have no reason to believe that in our lifetime, or the lifetimes of many generations yet to come, so strange a reversal of present conditions should occur. And again, that in this matter, we may be calmly judicial, we have reason at least for a moderate fear. Whatever state of unstable equilibrium, of unadjusted balance is implied, or actually is resident in this section of our earth, a section that has undergone the extremes of hypsometrical displacement, we may conceive that like the explosive cap, or the compressed spring, or the bent bow, it will win instant relief upon the impact of any force, deep-seated enough, and powerful enough, to liberate its tectonic strain. “I am thus brought to consider that world-wide source of terrestrial deformation--earthquakes; but I should forget the indulgence of your patience up to this point, if I should now undertake any partial review of these astonishing and alarming occurrences. I am deeply impressed, however, with an aspect of the subject that demands attention, that throws into sharp relief the prophecies of disaster, with which, willingly or unwillingly, we have all become familiar.”