The number of physicians, and surgeons, and medical men, whose testimony is brought to bear on the subject of diet, in the chapter which follows, is by no means as great as it might have been. There are few writers on anatomy, physiology, materia medica, or disease, who have not, either directly or indirectly, given their testimony in favor of a mild and vegetable diet for persons affected with certain chronic diseases. And there is scarcely a writer on hygiene, or even on diet, who has not done much more than this, and at times hinted at the safety of such a diet for those who are in health; particularly the studious and sedentary. But my object has been, not so much to collect all the evidence I could, as to make a judicious selection--a selection which should present the subject upon which it bears, in as many aspects as possible. I have aimed in general, also, to procure the testimony of intelligent and philanthropic men; or, at least of men whose names have by some means or other been already brought before the public. If there are a few exceptions to this rule, if a few are men whose names have been hitherto unknown, it is on account of the _aspect_, as I have already said, of their testimony, or on account of their peculiar position, as regards country, age of the world, etc., or to secure their authority for certain anecdotes or facts. In the arrangement of the testimony, I have been guided by no particular rule, unless it has been to present first that of some of the older and most accredited writers, such as Cheyne, Cullen, and Rush. The testimony of certain living men and authors, particularly of our own country, has been presented toward the close of the chapter, and in a very brief and condensed form, from design. The propriety of inserting their names at all was for a time considered doubtful. It is believed, however, that they could not, in strict justice, have been entirely omitted. But let not the meagre sketch of their views I have given, satisfy us. We want a full development of their principles from their own pens--such a development as, I hope, will not long be withheld from a world which is famishing for the want of it. But now to the testimony. DR. GEORGE CHEYNE.