CRUFT LABORATORY COMPLETE

The new Cruft high tension laboratory building is now practically completed, and will be ready for the use of Physics courses 4b, 4c, 15 and 17, and Engineering courses E17n and E20d which will be held there, probably by the end of next week.

The new building is the result of a bequest of $50,000 made by Miss Harriet Cruft, and is to be known as the Cruft Memorial Laboratory. Miss Cruft has also given an additional sum to be used in the purchasing of equipment.

The building is three stories in height, with a loft for storage purposes. The structure is absolutely fireproof, and represents the latest ideas in current construction. The floors, roof and stairways are built of reinforced concrete, while the outer walls are of brick and the inner walls of hollow tile blocks. The roof is slated, and has, on the top, a flat runway, on each end of which a steel lattice-work tower for supporting wireless antenna is to be erected. These have not yet been erected, but will be in place in a few weeks. The building contains 25 rooms, for research and instruction work. Five of these rooms are under ground, and will be used as constant temperature rooms. One of these, about 32 by 44 feet area, is to contain a storage battery of 100,000 volts. This storage battery, which will be the highest voltage storage battery in the world, involves many new problems in its insulation and switching devices, but considerable aid in solving them has been derived from the previous experience of Professor Trowbridge in his work with the 40,000 volt storage battery at the Jefferson Physical Laboratory.

Each room of the new laboratory is provided with equipment for turning it into a dark room for photographic purposes, and all are provided with water and gas, and a distributing board for electric currents. The currents available in each room at the outset will consist of 110 volts direct current, 110 volts 60 cycle alternating current, 220 volts 500 cycle alternating current, 500 volts direct current, and a storage battery voltage from 2 to 80 volts, in two volt steps. Ten of the rooms are also provided with insulated bushings through the floors, in such a way as to permit their connection with the 100,000 volt storage battery. The various alternating current lines through the building permit the use of a great range of alternating high potentials obtained from transformers.

The building was designed by Professor E. J. A. Duquesne and Professor H. L. Warren, and recent modifications have been designed and supervised by Professor W. S. Burke and Mr. Beard. The main contractor was Mr. Willicut, Ground was broken for the building a little over a year ago, and since then the work has been pushed as much as possible in order to have it ready for use this spring.

Professor G. W. Pierce has been appointed director of the Laboratory, and he and Dr. E. L. Chaffee will have direct charge of the work carried on there