Instruction in Physics in the University is carried on in two buildings, the Jefferson Physical Laboratory and the Cruft Laboratory. The older building, which forms the subject of this notice, is devoted to the study of general physics both elementary and advanced, the newer is intended for advanced instruction and research in the special fields of high frequency electric currents.

Perhaps the easiest method to follow in giving a short account of the activities of a laboratory is to describe the arrangement of the rooms and the uses to which they are put. The eastern end of the basement of the Jefferson Physical Laboratory is occupied by the machine shop, the carpenter shop and the glassblower's room. This department may be said to be the heart of the laboratory, for it is here that the instruments used in the courses are kept in repair and it is here that the special apparatus for investigation is constructed. The northeastern part of the basement contains the excellent new mounting for the twenty-one foot concave grating, together with other apparatus necessary for the study of problems in spectrum analysis and magneto optics. The electric current used in this work is furnished by a storage battery recently established in the old engine house at the eastern end of the main building. The whole equipment is as good as any in this country. It is at present employed in a study of the relation of the Zeeman effect to spectral series. The central portion of the basement is devoted to storage and to a number of small research rooms used by Professor Davis and his students. The southwestern part of the same level is occupied by an optical laboratory. In the northwestern portion, Professor Bridgman carries on his well-known researches on phenomena at high pressures. In a vault under the western end of the building, Professor Sabine conducts those investigations on sound which have so largely helped to establish the scientific reputation of the Laboratory.

The eastern end of the first floor is occupied by the large lecture room and by cabinets for lecture apparatus; next comes a smaller lecture room and the students' laboratory devoted to Physics 1. The western end is taken up by research rooms devoted to the study of thermo-magnetism and to the investigation of the extreme ultra violet part of the spectrum.

The third floor is occupied by three small lecture rooms, by the reading room, by part of the Physics 3 laboratory, by Professor Davis' new heat laboratory and by the laboratory devoted to radioactivity. The eastern end of the fourth floor is taken up by the large elementary laboratory in which Physics B and Physics 1 are conducted, the central portion is devoted to Physics 3, and the rest is given up to research. It is in the western end of this floor that the high tension storage battery constructed by Professor Trowbridge is installed. Thanks to this piece of equipment, Professor Duane, Dr. Webster, and several graduate students are enabled to carry on very important researches connected with the X-rays.

The Jefferson Physical Laboratory is today a very efficient building in most respects. This is the more remarkable since it was one of the first physical laboratories built in this country. There is one improvement, however, which is really needed; the presence of heavy machinery in a building where delicate measurements are to be made, is most undesirable; it is much to be desired, therefore, that a special building be erected to contain our machine shops. Another question of great importance to the Department is the increase of our income, for the growth of research has considerably outstripped the funds available from our Endowment