During the third and fourth years are taken up, respectively, structural and historical geology. Both these subjects are taught largely by lectures, illustrated by charts and diagrams, a select set of specimens for the table, and a few such specimens as can be passed around the room. In the historical geology special care is taken to furnish for class use as many specimens as possible of the typical rocks and fossils of the various ages. It is nearly impossible to provide so abundantly, however, as for mineralogy and lithology. As regards examinations, the methods used are as follows: The first half hour of each exercise is taken up with answering questions or identifying specimens, the examinations in all cases being written. The ground covered by each examination includes all that has been gone over during that year previous to the examination. After the examination is finished, the instructor briefly answers and explains the questions. The papers so handed in are marked by the instructor and returned the following week. All of this serves to enable the class to keep a comprehensive grasp of the subject constantly in hand. At the end of each year's work a final examination of three hours in length is given, covering the complete subject. The final rank given each member is made up equally from an average of the term's work and the final examination. This course has proved decidedly popular. The instruction was originally given in the Geological Department of the Institute of Technology, in a room adapted to seating thirty-six persons. This was gradually crowded to accommodate fifty-six persons. At the beginning of the last four-years' course the number of the applications was so large that each applicant was required to sign a printed statement promising to be present at all exercises for the four years, except for good and sufficient reasons. One hundred and seventeen persons gave the required promise. In order to meet this demand, two divisions were formed, and on each Saturday afternoon the same lesson was repeated. In order to defray the additional expense of the second division the members of the class voluntarily contributed three dollars each. The labor of repeating the lessons on the same afternoon proving too great, provision was made the second year to transfer the instruction to the large lecture hall of the Natural History building, where accommodations were made for one hundred and twelve students. The work has since been carried on there, and a complete new set of specimens, diagrams, etc., is gradually being obtained. The membership of the class is, of course, principally made up from Boston and the towns immediately surrounding, but a few come from places as far distant as towns in Connecticut and Rhode Island, from Bridgewater, Scituate, Framingham, Fitchburg, Lowell, Lawrence, and Beverly.