THE narrative to which this note is introductory was found among the papers of the late Professor S. Erastus Larrabee, and, as an acquaintance of the gentleman to whom they were bequeathed, I was requested to prepare it for publication. This turned out a very easy task, for the document proved of so extraordinary a character that, if published at all, it should obviously be without change. It appears that the professor did really, at one time in his life, have an attack of vertigo, or something of the sort, under circumstances similar to those described by him, and to that extent his narrative may be founded on fact. How soon it shifts from that foundation, or whether it does at all, the reader must conclude for himself. It appears certain that the professor never related to any one, while living, the stranger features of the experience here narrated, but this might have been merely from fear that his standing as a man of science would be thereby injured.