In government, in industry, in architecture, the imperial age was one. The underlying policy of imperialism is to exploit the life and resources of separate regions for the benefit of the holders of privilege in the capital city. Under this rule, all roads lead literally to Rome. While, as the German historian, W. H. Riehl, points out, the provincial highroads served to bring the city out into the countryside, the railroads served to bring the major cities together and to drain the products of rural regions into the metropolis. It was no accident that the great triumphs of American architecture during the imperial period were the railroad stations; particularly the Pennsylvania and the Grand Central in New York, and the Union Station in Washington. Nor is it by mere chance that the Washington and the Pennsylvania stations are the monuments to two architects, McKim and Burnham, who worshiped most whole-heartedly at the imperial shrine. With capital insight, these men established the American Academy at Rome: they recognized their home. Esthetically considered, it is true, perhaps, that the finest element in the Pennsylvania station is the train hall, where the architect has dealt sincerely with his steel elements and has not permitted himself to cast a fond, retrospective eye upon the Roman baths. When all allowances are made, however, there remains less for criticism in the railway stations and the stadiums--those genuinely Roman bequests--than in any of the other imperial monuments. Indeed, so well does Roman architecture lend itself to the railroad station that one of the prime virtues of such a building, namely ease of circulation, was even communicated to the New York Public Library, where it is nothing but a nuisance, since it both increases the amount of noise and diminishes the amount of space for reading rooms that are already overcrowded.