The new plant of the Allison Div. of General Motors Corp. at Indianapolis, Ind., is the world's latest version of the air conditioned, artificially lighted, windowless industrial building. Its program for the manufacture of aircraft engines for the U. S. Army calls for a high degree of precision and careful handling of materials. Air conditioning is thus an essential in avoiding the effect of temperature changes on gages and precision machines, etching of highly polished metal surfaces because of perspiration, and for providing the comfortable conditions that are necessary because of the concentration and skill required of the workmen. The building and its equipment are unique in many respects; among its features are: (I) A combination of natural well water, "Freon" refrigerant, natural air and auxiliary oil burners in the air conditioning and heating scheme.
(2) The first application of a new type of fluorescent lighting to a large scale industrial lighting problem duplicating mid-day north light 24 hours a day. (3) Because of the unique combination of factors in heat insulation, air conditioning and artificial lighting it will take relatively less power to create this new approach to ideal working conditions. (4) Unusual paralleling of a diesel power plant with local utility electric lines to provide an adequate, uninterrupted source of power with unusual economy. (5) Unusual architectural effect, due to windowless feature and use of glass brick panels. (6) An unusual tooling set up for precision work. Four new buildings on 53 acres of land comprise the plant; they include the manufacturing building with adjoining office building, a test building and a gate house. Welded construction of steel columns and trusses is used throughout. R. H. O.