There was published, several years ago, by Gould & Lincoln, Boston, a little work entitled: "TO DAIMONION, OR THE SPIRITUAL MEDIUM. _Its nature illustrated by the history of its uniform mysterious manifestations when unduly excited._ By TRAVERSE OLDFIELD." This author deals largely in quotations from ancient writers in illustration of his subject; and as an attempt to explain the mysteries of clairvoyance, trance, second-sight, "spirit-knockings," intelligent movements of physical bodies without hands, etc., his work has claims to our attention which do not usually pertain to the class of works to which it belongs. "_To Daimonion_" (the demon), or the "spiritual medium," he supposes to be the _spiritus mundi_, or the spirit of the universe, which formed so large an element in the cosmological theories of many ancient philosophers; and this, "when unduly excited" (whatever that may mean), he supposes to be the medium, not only of many psychic and apparently preternatural phenomena described in the writings of all previous ages, but also of the similar phenomena of modern times, of which it is now admitted that Planchettism is only one of the more recently developed phases. For some reason, which seemed satisfactory to him, but which we fear he has not made clear or convincing to the mass of his readers, this writer assumes it as more than probable that this _spiritus mundi_--a living essence which surrounds and pervades the world, and even the whole universe--is identical with the "nervous principle" which connects the soul with the body,--in all this unconsciously reaffirming nearly the exact theory first propounded by Mesmer, in explanation of the phenomena of "animal magnetism," so called. Quotations are given from Herodotus, Xenophon, Cicero, Pliny, Galen, and many others, referring to phenomena well known in the times in which these several writers lived, and which he supposes can be explained only on the general hypothesis here set forth; and in the same category of marvels, to be explained in the same way, he places the performances of the snake-charmers, clairvoyants, thought-readers, etc., of modern Egypt and India.