The student who seeks in a preparation only the appearances described in a textbook is not studying in a scientific way. He will constantly accept the author, instead of using his own impressions for the basis of deductions, guided by the experience of others. With an unbiased mind the student should take each specimen for that alone, which it, itself, presents; and upon this he should build his conclusions. He should seek in the textbook the things he _finds_ in the material; not _seek_ in the latter the things he _reads_ in the former. Thus may he escape superficiality, avoid errors and hasty judgments, and build up for himself a sure foundation of knowledge. For these reasons the students in my laboratory course, having been thoroughly prepared for such work by the study of normal tissues in the histologic laboratory, are given the pathologic material as _unknowns_, which under careful guidance, they are enabled to work out for themselves to a satisfactory conclusion. The student is further aided in the fixing of his impressions, and in their expression, by means of the drawings and written descriptions which he is required to make of the preparations. In this way the faculties of observation and expression receive a training that is not otherwise possible. It is true that such a course of instruction is difficult for the student whose previous training has been deficient in the cultivation of these most important faculties; for this reason it is the more necessary that he should now apply himself to work in the scientific method. That this method of teaching takes much more of the instructor’s time is true; that it takes too much time cannot be granted when measured according to the results obtained. The frequent objection of the student that he cannot draw only emphasizes the necessity of that student’s receiving the necessary training to enable him to reproduce his visual impressions.