Philadelphia, which had hitherto always been extremely conservative in architecture, soon began to erect some of the most singular and fantastic structures that could well be imagined; but fortunately the refined simplicity and fertile originality of such men as Wilson Eyre, Frank Miles Day & Bro., and Cope & Stewardson have prevailed, and in both city and suburban work they and certain others have done and are doing much to counterbalance the character of the eccentricities of their predecessors, as shown in buildings for the University of Pennsylvania and the Academy of Arts and Sciences. But the restless activity of Eastern loom and machine shop, and of Western farm and mine, seemed to meet and concentrate in Chicago—the _entrepôt_ for the raw material of the West and the finished product of the East. The unprecedented increase in value of land, the low price of iron and steel, with the introduction of high-speed elevators, combined to develop a new type of sky-scraper; and as the nature of the soil was entirely unlike that of other cities, the foundations of these buildings presented problems which were solved by Chicago architects in various ways hitherto untried. The Rookery by Burnham & Root, Pullman Building by S. S. Beman, and the Auditorium (opera house, hotel, and office building in one) by Adler & Sullivan, at the time of their completion were most notable examples of architectural engineering, and were soon followed by many others more or less similar, designed by W. L. B. Jenny, Holabird & Roche, Henry Ives Cobb, and others. The buildings for the Chicago University, the Athletic Club, and Newbury Library, by the last-named architect, show a high degree of ability; the peculiarly rich arabesque ornamentation designed by Louis H. Sullivan, and the direct and rational handling of the buildings upon which it was used, are certainly indicative of the spirit of enthusiasm and conscientiousness of a well-trained mind. It is by such characteristics that John W. Root was able to accomplish so much for the advancement of architecture in the West. What Krupp and Stumm had done for the employees in their works in Germany, Pullman determined to do for his men and their families here; and a town, with dwellings, schools, churches, water-works, etc., for many thousand inhabitants was designed and built by S. S. Beman, which has been reported by experts to be the best of its kind. In Chicago, in 1893, was held our second international Exposition; and that the exhibits should be suitably housed, some of the most prominent architects of the country were called together, buildings were assigned to each of them, and Frederick Law Olmsted was appointed to lay out the grounds, waterways, and bridges. [Illustration: TRINITY CHURCH, BOSTON.]