A greater difficulty lies with the teacher. Not only must he select his preparations with wisdom, so that in the necessarily limited time of the course, the student may receive the greatest benefit; but he must be tactful and patient in leading the student to work for himself. It is easy to give a demonstration and then tell the student to work; it is very much more difficult and nerve-consuming to make the student _see_ and _demonstrate_ for himself. The relation of the microscopic preparation to the gross anatomy must be shown, and, when possible, demonstrated by macroscopic preparations; further, the relation to the clinical symptoms and physical signs must be made clear, so that the student receive not a narrow conception of pathologic histology as something in itself separate and complete, but as a foundation-stone to the broadest conception of diagnosis, whereby the real unity of his studies will be revealed. Moreover, the teacher must be fully awake to individual differences and needs, and carefully shape his teaching influence upon each student accordingly. The problem of the individual equation becomes especially difficult in a course of this kind. The laboratory course in histologic pathology, in the University of Michigan, follows the general order given in the second part of this book, beginning with the diseases of the blood and the circulation, and finishing with the special pathology of the most important organs. A preparatory training in general technique is first given. About one hundred and seventy-five prepared specimens, each illustrating some especial pathologic point, are given to the class as unknowns for diagnosis. In addition each student is required to prepare about fifty slides from fresh material, performing for himself all of the necessary technical manipulations, according to the methods given in this manual. To further the work in this course, and to meet the needs of advanced students and of practitioners, this book is primarily intended. ALDRED S. WARTHIN, Ph.D., M.D. ANN ARBOR, January, 1897. CONTENTS PART I. THE SOURCES OF PATHOLOGIC MATERIAL AND THE METHODS OF OBTAINING IT FOR EXAMINATION. CHAPTER PAGE _Introduction_ 1 I. The Autopsy: General Considerations 3 II. The Order of the Autopsy 24 III. The Protocol 33 IV. The External Examination 41 V. The Examination of the Spinal Cord 53 VI. The Examination of the Head 63 VII. The Main Incision: Thorax and Abdomen 96 VIII. The Examination of the Thorax 106 IX. The Examination of the Mouth and Neck 131