The Materia Medica, after all, furnishes us with the powder, shot, and cannon by which we assail the citadels of disease, and, without this materiel of war, all our fine-spun rules of gunnery and fortification are of no avail. Dr. Thomson has dedicated a long" professional life, not, indeed, to the exclusive study of this branch of our art, but certainly to a more than ordinary cultivation of it:?he is, therefore, well qualified to bring-this portion of study to the greatest degree of perfection of which it is, at present, susceptible. He laments that a wrong-direction is given, by the corporate bodies, to the routine of the tyro's studies, by compelling him to commence his medical education with the materia ree^'ca ; whereas he should be directed previously to attend at least one couioe of natural history, botany, chemistry, anatomy, and physiology, without some knowledge of which, he cannot comprehend the doctrines delivered in a course of materia medica, far less those relatingto therapeutics. The author flatters himself that, in this work, he has rendered the mistake in medical education sufficiently evident, and, consequently, tended to effect its correction. Dr. Thomson appears to have availed himself, with his characteristic assiduity, of the labours of the Continental chemists and medical writers, as well as of his own country and America, to enrich his work; and, although much of it must necessarily be a compilation, yet the author has introduced the results of 30 years' attentive observation in the treatment of disease into the work, and thereby given a considerable portion of original information to his readers. This first volume is divided into three parts?first, on the general action ?f medicines?secondly, on the classification of medicinal agents?and, thirdly, on materia medica and therapeutics. It must be evident that such a work is insusceptible of analysis, and not a fair subject of criticism. The No. XXXVi.