St. Louis has one passenger station to serve as city gate for the traffic that comes and goes at that important railroad centre. That gate is the chief through passenger traffic point of the world. From its train-shed one may take through trains to every corner of the United States and a few distant corners of Mexico and Canada. St. Louis, like most Western cities has no volume of suburban traffic as New York, Boston, or Philadelphia, but it is a consequential point for through passengers. The better to serve the needs of the 22 different railroad systems entering that city, the Union Station was built a dozen years ago. It was thought to be big enough to last St. Louis many years. Before the World's Fair of 1904 opened in that city the Union Station was already judged inadequate, and an elaborate plan was consummated for its enlargement. When the Union Station was originally planned, St. Louis demanded a gate that would be worthy of her size and dignity. No type of through station would do, the head-house terminal was demanded and built, even though in actual practice it necessitated backing each arriving train into the shed. A station of giant size with the largest train-shed in the world was built and hailed with a glad acclaim by the Western town. When the station was found inadequate, the engineers found their plans for enlarging it would have to be adapted to a very confined area, proscribed by immovable railroad properties to the south, highway viaducts to the east and west, and a granite head-house, costing several million dollars, to the north. Within that confined area, they were to correct the evils of insufficient capacity--a train-shed with a single 4-track throat and some standing tracks of but 3 cars' length, inadequate baggage arrangements, and lesser evils. Within two years, they had substituted, without increasing the area of the Union Station property, a 10-car capacity for each of the 32 tracks of the train-shed, a double throat with 6 tracks, increased concourses and distributing platforms for passengers, and a complete subway system for the handling of baggage. The prosecution of that work, while the station was in constant and busy use, ranks as one of the marvels of latter-day practical engineering. From the standpoint of the architect, no other station has yet been built in the United States that can compare with the new Union Station at Washington. For years, the overcrowded railroad stations at that city have been but wretched gateways to the national capitol. Now the city that is fast becoming the Mecca of all Americans has an entrance worthy of her dignity, and in keeping with the increasing magnificence of her architectural works.