The object of "the Book" is to set forth the great fact of the reciprocal influence existing between the nervous system and the digestive organs, and the power they mutually exert in the causation and cure of diseases; and this, whether the diseases originate in disturbance _primarily_ directed to the brain or any other portion of the nervous system, or to the _digestive organs_; whether the result of accident, such as mechanical injury, or other local manifestations more commonly termed disease. In the book before us we shall find an ample refutation of many misconstructions and misapprehensions of Abernethy's views; misconstructions which have tended to obscure principles, remarkable for their simplicity and truthfulness; to impede the beneficial application of them in a manner which has been equally injurious to the public and the profession, and which, have impressed on mankind a very inadequate idea of the obligations due to the distinguished author. His views were said to be theoretical and exaggerated, whilst they were conclusions logically deduced from facts; and so far from the pervading power of the influences to which he proximately attributed the causation and cure of disease having been exaggerated, the onward study of his principles only serves, by the discovery of more multiplied and refined applications of them, to fill in with additional illustrations the accurate outline which he has so truthfully drawn. He never wrests a fact to a conclusion to which it does not legitimately lead. In virtue of that suggestive quality of his mind (so important an aid in philosophical inquiries), he occasionally, in all his writings, puts forth suppositions, but these only as _questions_, the next in the order of inquiry, and these he asks of nature alone.