PROFESSOR CHATBURN: We frequently ask our students toward the end of the semester to bring the textbook down- or up-to-date. If we are using a certain man's textbook published six or seven years ago, we ask our students to write an additional chapter for that textbook, using information which they can get from journals, magazines and other textbooks.

THE BUILDING AND EQUIPMENT OF THE ROCKEFELLER PHYSICAL LABORATORY OF THE CASE SCHOOL OF

APPLIED SCIENCE.

BY DAYTON C. MILLER,

Professor of Physics, Case School of Applied Science.

A gift from Mr. John D. Rockefeller, made about two years ago, enabled me to materialize some plans I had long been making; the result is this building, which has been completed about six months. Really it is not yet quite completed as far as equipment is concerned. I wish very briefly to explain some general principles underlying the arrangement and equipment, after which you are invited to inspect the laboratories.

The purpose of the building is first to provide for the instruction of classes of two hundred and fifty students in general physics, including lectures, recitations and laboratory work. This determined some of the larger parts of the building. It has three floors and an attic, but no basement. The dimensions are 75 feet by 132 feet..

The work in general physics is provided for by a lecture room seating 250, with a preparation room adjacent, and by three recitation rooms, on the third floor; by a general laboratory consisting of one large room and four smaller rooms accommodating about 65 at one time, on the second floor; and by a locker room for 204, and a lavatory, on the first floor.

The students being thus accommodated, three offices were provided for the director and his assistants, and the remaining space was arranged for research. Adjacent to the director's office are two private laboratories, and connecting with the first assistant's office is a private laboratory, each having conveniences for special work. The other research rooms are on the ground floor and the third floor. Some of these are arranged for particular uses. There is a balance room, a galvanometer room, a room for mercury apparatus, one for machinery requiring considerable power, a constant temperature room with daylight for comparators and dividing engines, a constant temperature room for clocks and seismograph, photometer, spectroscope and photographic rooms, six dark rooms, a sound laboratory, a pendulum shaft, a battery room, a mechanician's shop and office, several small research rooms without special arrangements, a room for the heating and ventilating apparatus, janitor's closets, and storage rooms and several private lavatories.

There are about thirty piers in the building, and throughout there are wall shelves and outside window shelves. Many rooms are arranged for perfect darkening; conduits permit the running of wires from one room to any other, while 44 electrical circuits run from various points of the building to a central connecting board in the battery room, permitting many distributions and connections without special wiring. The distribution of gas, electricity, hot and cold water, steam, compressed air and exhaustion is unusually complete.