Born in the 18th century, its adolescence spent in the 19th, the nation's capital reached adulthood only with the arrival of this century's complexities.

Washington 80 years ago was small in comparison with Baltimore, Philadelphia, New York or Boston. To many, it was still a provincial big town with a terrible climate and an excess of politicians, a place to pass through and look at briefly on the way to newly developing Florida.

But new technological, political, economic and demographic forces were destined to give Washington its eventual fleshy, grown-up city form: the automobile and the telephone; the phenomenal expansion of government accelerated by new ideas about the interventionist role of the federal government and by the necessities of war; the optimism of the Roaring '20s and the New Deal of the depressed '30s; Washington's relative economic stability, expansion of business and increasing population; and with mobility, enduring employment, and air conditioning, the discovery that Washington was a livable city.

In 1918, at the end of World War I, there were approximately 120,000 federal civilian employes in Washington. In 1943, halfway through World War II, the number reached 285,000.

The population of D.C. rose from 487,000 in 1930 to 553,000 in 1940, primarily because of New Deal activity. Prior to 1930, the number of federal workers had actually decreased, but overall D.C. population rose steadily as commercial activity and immigration increased during the '20s. By 1940, the Washington metropolitan area population hit 1 million.

Congress and local citizens realized earlier in the century that things were going to change even more rapidly than before. Without proper planning and management, Washington might return to some of the physical conditions deplored in the 19th century. And the pressure to take the short-term, expedient approach was difficult to resist in the face of real estate developers or government agencies motivated primarily by their own immediate needs and points of view.

The L'Enfant and McMillan conceptions had demonstrated the value of making and adhering to long-range plans. Thus, both new laws and planning bodies aimed at directing the city's physical growth seemed indispensable:

*In 1910 the Fine Arts Commission was permanently established and the Height of Buildings Act was passed.

*In 1920 a zoning ordinance separating residential, commercial and industrial uses of land and stipulating height and area limits was adopted.

*In 1926 the National Capital Park and Planning Commission was created and the Public Buildings Act, authorizing construction of the Federal Triangle, was passed.

*In 1930 the Shipstead-Luce Act passed, giving the Fine Arts Commission the authority to review all new development adjoining public parks and government buildings.

However, rational acts of government historically have failed to keep pace with the forces of technology, politics, economics and demography. Accordingly, as railroads had dramatically transformed the scale and landscape of continents, so the automobile was to transform the scale and form of cities.

Street car and bus lines provided some mass transit, theoretically diminishing the need for personal means of conveyance. But Washington's commitment to relatively low density -- even downtown -- made suburban development and sprawl inevitable. So while row housing followed street car lines northward and eastward from downtown, new roads and automobile-oriented subdivisions proliferated in other areas, created by developers and designers who correctly anticipated the future.

Whole neighborhoods materialized: Shannon & Luchs built Burleith, west of Wisconsin Avenue, in the mid-'20s; Waverly Taylor built Foxhall Village, west of Georgetown, between 1925 and 1930; Wesley Heights and Spring Valley were laid out northwest of Cleveland Park, but with roads conforming more naturally to the terrain, resulting in sometimes radical distortions of the Washington street grid.

Between 1900 and 1930, after construction of bridges spanning Rock Creek Park, the building of mansions along Massachusetts Avenue and of apartments along Connecticut Avenue reinforced the designation of these areas as "special." However, Georgetown had not yet been gentrified, and Capitol Hill, Southwest, Foggy Bottom and close-in Northwest were being further abandoned to tenancy by those unable to take advantage of the new mobility.

At the same time, the inexpensive farmlands of Maryland and Virginia were being discovered and suburbanized by the automobile and the detached home of the American dream. Crossing the Potomac -- at 14th Street, Memorial Bridge, Key Bridge at Georgetown and Chain Bridge -- made the formerly rural northern Virginia counties readily accessible. By 1925, the metropolitan area stretched from Fairfax to Rockville to Hyattsville.

Meanwhile, the federal government never stopped building. The National Museum (later the Museum of Natural History) was completed in 1910, the first building erected in accordance with the McMillan plan. The Freer Gallery and the Lincoln Memorial were subsequently constructed. In the '30s, after some debate about its location, the Jefferson Memorial was built. It formed the southern terminus of the cross-Mall, north-south axis visually linking the Memorial to the White House and the off-axis Washington Monument.

The Federal Triangle project, conceived by the McMillan Commission at the beginning of the century, finally began in 1926, supported enthusiastically by Secretary of Commerce Herbert Hoover. Guided by Treasury Secretary Andrew W. Mellon and planner Edward H. Bennett, it involved demolition and rebuilding of the area bounded by Pennsylvania and Constitution avenues between 15th Street on the west and 6th Street -- the apex of the triangle -- on the east.

Historian Frederick Gutheim points out that "the triangle area was the large squalid slice of land that had accumulated an infamous reputation in the 19th century as a haven for the city's criminal element, and included the area known as Murder Bay." Only the Romanesque-styled Post Office, built in 1899, had been sited in this blighted lowland subject to periodic flooding. The classically inspired Federal Triangle, made up mainly of office buildings, was one of Washington's first slum clearance projects, and it foreshadowed things to come.

But despite such ongoing efforts to complete the symbolic and functional monumental core of Washington, the government's policies were inexorably shifting. Pragmatism and the new mobility had engendered thoughts of dispersal. Geographic concentration of the government in proximity to the White House or the Capitol seemed both unnecessary and undesirable. Parking in the center of Washington had become nightmarish, because few buildings had parking garages. Every available foot of curb space and open space, paved or otherwise, was filling with cars.

According to historian Gutheim, "a traffic study performed in 1934 . . . revealed that 'the proportion of people in Washington who use private automobiles or taxicabs is over twice the average reported from six other cities,' a larger proportion than Los Angeles." Between 1920 and 1930, auto registrations in the District increased 400 percent!

As the '30s ended and war clouds gathered, temporary buildings from World War I still occupied parts of the mall. Citizens, mostly black, were still crowded into countless, substandard alley dwellings. Neighborhoods embarrassingly near to the White House and the Capitol were deteriorating.

World War II would represent a six-year hiatus in coping with urban problems eclipsed by the problems of fighting wars globally. But it was only a postponement.

NEXT: The Last Forty Years