The building, of which a view is given on p. 131, is the largest of the group of buildings on the institute campus. It occupies an area of about 20,000 sq. ft., with over-all dimensions of 122 x 200 ft., and is made up of a main rectangular structure, 67 x 200 ft., which contains the general laboratory 55 x 200 ft., and the main corridor 12 x 185 ft., together with two rectangular wings, 55 x 55 ft. each, and projecting to the front. The west wing accommodates a lecture hall, capable of seating 300 persons, with a standards and research laboratory above, each 55 x 55 ft. and free from columns. Under the lecture room is the high potentials and insulations laboratory 55 x 55 ft. In the east wing are located, in the basement, the telephone laboratory, two offices and two lecture or recitation rooms, while on the main floor are the department offices and library, and on the upper floor are found the design room, a lecture room, three offices and a blueprint room.

The site of the building is on sloping ground, which permits of full basements above the ground level for the two wings and corridor, with entrances at east and west ends of basement corridor; while the first floor of the general laboratory is at the ground level, giving entrance at the west end to the railway tracks. which connect with the local street railway system. The main building is, therefore, but two stories high, with third floor gallery. The wings are three stories in height.

All foundations are of concrete, which extend somewhat above ground and are finished on the exterior by rough picking.