This volume is comprised of a series of essays whose purpose on one hand is to exhibit a tolerable sketch of the human mind; and, aided by the lights which the poet and orator so amply furnish, to disclose its secret movements, tracing its principal channels of perception and action, as near as possible, to their source: and, on the other hand, from the science of human nature, to ascertain, with greater precision, the radical principles of that art, whose object it is, by the use of language, to operate on the soul of the hearer, in the way of informing, convincing, pleasing, moving, or persuading. The Contents are divided into the following three Books: The Nature and Foundations of Eloquence ; The Foundations and Essential Properties of Elocution ; and The Discriminating Properties of Elocution .