The real importance of world's fairs in the 193os can be measured by considering them only as few in long series of such events dating from 1851, the year of the Crystal Palace Exposition in London. Before the Crystal Palace, all expositions had been national. The 1851 exhibit was international, and included innumerable examples of craft and industry as well as art. The United States sent, as part of its collection of 1760 exhibits, false teeth, chewing tobacco, artificial legs, and air-exhausted coffins. Prince Albert, sponsoring the affair, looked at it with lofty idealism as symbolizing the unity of mankind. He spoke of it as a living picture of the point of development at which mankind has arrived, and new starting point from which all nations will be able to direct their future exertions.' At any rate, it was clearly international. As you all know, the most influential part of the exhibition was not, paradoxically, any of the seventeen thousand individual exhibits, but the exhibition building itself. For the next seventy-five years builders of railroad terminals, palm palaces, and further exposition halls were to rely heavily on Paxton's provocative crystalline effects and his utilization of mass production methods in making prefabricated components. By the 1930os what was revolutionary in 1851, namely the great glass container lighting exhibits with daylight, was passe and, instead, the opposite condition became desirable. Exterior light was generally excluded, and windowless interior spaces were electrically lighted with what one critic of the Chicago fair in 1933 called gas-filled tubes. The neon light, so brilliant and gay at night, and the use of intense color values, turned what used to bethrough the British Empire exhibit of 1924-a comparatively dignified policy of exhibition into an atmosphere of the carnival. A Century of Progress, the slogan for Chicago's fair referring to the time elapsed since the founding of the city, brought before the public many new scientific discovery or improvement. But, and here is the weakness, the exhibits were frankly commercial advertising, privately financed, whereas the Chicago fair of 1893, and most others, were financed with public subsidy. Perhaps because of the spirit of progress, the Chicago Fair Commission in 1933 chose as architects men with forwardlooking point of view.2 To repeat the architectural debacle of 1893 would only have played into the hands of reactionaries and revealed to the immense depression-era crowds real lack of progress. Thirty-eight million people went there in two years to saunter up and down the threeand-one-half miles of lakefront.