It is to the unlikely conjunction of a smooth-skinned '30s car (as streamlined as a teardrop), a rigorous geometry (the circle in the square) and a memory of forests (the cool pines of Wisconsin) that Frank Lloyd Wright, the architect, owes the astonishing design of his best commercial building.

It was built by Johnson Wax on land of no distinction in bland Racine, Wis. It is a lab-and-office complex that feels like a church.

Its windows are not planes of glass, but stacked-up Pyrex tubes. Sixty slender, hollow columns spread to form its ceilings -- they look like concrete lily pads. Its 15-story tower, another plantlike form, is rooted like a tree.

Its start was not auspicious. Wright was 69 and very nearly broke when, 50 years ago, he first encountered Herbert Johnson Jr., the wax company's young president. No sooner had the two men met than they began to fight.

"He insulted me about everything, and I insulted him, but he did a better job," Johnson recalls. "I came back from Taliesin, Wright's Wisconsin studio at Spring Green and said, 'If that guy can talk like that he must have something . . .' He had a Lincoln Zephyr, and I had one -- that was the only thing we agreed on. On all other matters we were at each other's throats."

Art history must thank their mutual delight in the beauty of their cars. Johnson had his architect. Wright had found a patron. The great complex that would grow from their subsequent agreements is the subject of "Frank Lloyd Wright and the Johnson Wax Buildings: Creating a Corporate Cathedral," the exemplary exhibit that goes on view today at the Renwick Gallery of the Smithsonian Institution.

It is one of three events held in Washington this weekend that celebrate the genius of the greatest of our architects, that cranky and combative Whitmanesque romantic:

*"Frank Lloyd Wright: Architectural Milestones," an all-day seminar, will begin today at 10 at the Baird Auditorium of the Smithsonian's Museum of Natural History. Jonathan Lipman, the architect who organized the Renwick show, will speak on the Johnson Wax Administration Building. Architectural historian Jack Quinlan will discuss its most important precedent, Wright's skylit Larkin Building in Buffalo, N.Y., which was built in 1903 and destroyed in 1950. Kathryn Smith will talk on Wright's Imperial Hotel in Tokyo, and then Donald Kalec will discuss Oak Park, Taliesin and Taliesin West, the three homes the master designed for himself. Those interested in attending may register at the door.

*"Frank Lloyd Wright and Viollet-le-Duc: Organic Architecture and Design from 1850 to 1950," is now at Jo Tartt's Gallery, 2017 Q St. NW. Its subject is the often overlooked 19th-century impulse that drove Wright's 20th-century designs. The show, which runs through May, will be on view today and from 10 a.m. to 3 p.m. tomorrow.

*Jonathan Lipman's exhibit at the Renwick includes examples of the furniture Wright designed for Johnson Wax, models of the buildings, mock-ups of their columns, photographs and films, and extraordinary drawings from the master's hand. It is just the sort of show that ought to be displayed, but hardly ever is, at the National Building Museum. Nothing is more difficult than arranging an exhibit that lets one comprehend the details and scale of an intricate and odd -- and of course absent -- building. The messages delivered by Lipman's traveling exhibit, and its accompanying catalogue, could be enhanced only by a visit to Racine.

There is something oddly plantlike about Wright's scheme for Johnson Wax. Each detail encountered there is echoed by another. The roundness of the chairs, of the desks and of the desk drawers is rehearsed by the roundnesses of balconies and columns, the round floors of the tower, and the piled Pyrex tubes. Wright's buildings in Racine look as if they grew.

The seeds from which they sprouted were three buildings that the architect had designed years before.

The scheme for the Great Workroom of the Johnson Wax Administration Building recalls the soaring enclosed space, also lit by skylights, also ringed by balconies, of the Larkin Building Wright had built 33 years before. The spreading lily pad columns were first conceived by Wright in 1931 while he was designing a newspaper plant in Oregon, a building never built. These two linked ideas -- one concerning space, one concerning structure -- were driven into order by the architect's allegiance to the circle and the grid.

Wright never cared for soulless forms. From the gardens of his childhood, the intricate designs of Viollet-le-Duc, the twists of art nouveau, and the complex interweavings of Louis Sullivan's ornaments, he took his love of plantlike forms. But -- as the show at Tartt's makes clear -- he honored Euclid, too.

Equilateral triangles, hexagons and grids generate his floor plans. The lamps he designed for Chicago's Midway Gardens (Jo Tartt has acquired the only surviving example) are based on the octagon. He made vases that, despite their plantlike decorations derived from Viollet-le-Duc, are really hollow spheres. Much as Wright adored leaves and twining tendrils, he loved circles, too.

His Johnson Wax Administration Building might be called a garden inside a machine.

One sees little from the outside but long, curve-cornered walls and miles of Pyrex tubing. In his drawings, to show scale, Wright sketched beside those flowing walls his own beloved Lincoln. He never cared for cities, he sought some rural Eden. His building, like a well-built car, seals out Racine.

"High time," said the architect, "to give the hungry American public something truly streamlined." But when he spoke about the spirit of the inside of the building, he used another voice.

Wright compared the experience he was seeking to being "among the pine trees, breathing fresh air and sunlight." He called his spreading columns "dendriform" or "tree-shaped," and gave to their three parts terms he borrowed from botany: He called the shaft "the stem." The ringed top of the column, where the lily pad begins to spread, Wright termed "the calyx." "Petal" was the word he chose for the pad itself.

(The columns he designed, despite their hollow stems, proved far stronger than trees. They were required by local building codes to support 12 tons; they easily bore 60. Wright put up one and tested it by loading it with sandbags and pig iron. An old film of that test is included in the show.)

Even from the outside, the ceiling seems to float. The outside walls don't touch the roof; there's a band of light between them. Light pours into the Workroom from the skylights between the petal-rounds.

"A silly urge comes over you to lie flat upon the bottom of this pool of liquid light and stare up at the lily pads -- of concrete -- that float upon its glassy surface," exulted one stunned visitor when at last the building opened in 1939. The opening was attended by 26,000 people. The employes loved it. A company study concluded that, following the move into Wright's building, the efficiency of the company's office operations improved by 15 percent and in some departments by 25 percent.

The laboratory tower, completed in 1950, suggests a man-made tree. The laboratory floors -- every other floor is round, the ones between are square in plan -- are cantilevered like branches from a trunk. The foundation of the tower is a 54-foot taproot stuck into the ground. One microbiologist who worked there when the tower opened said he felt he was "in heaven."

"Neither structure is just a building," Wright insisted. "Each one is a life in itself."

It is that sense of the organic, of buildings -- and not buldings only, but chairs and lamps and vases -- grown as if from seed, that ties Wright's modern structures to the gothic-revival buildings of Euge ne Emmanuel Viollet-le-Duc (1814-79). In the Frenchman's structures, too, every cell of detail seems bound to every other. Wright called his predecessor's writings "the only really sensible book on architecture in the world . . . That book is enough to keep, in spite of architects, one's faith alive in architecture."

Flowers bloom and tendrils twist in the lamps and chairs and drawings now on view at Tartt's. Wright's roots are here apparent. Two different families of form, one geometrical, the other botanical, are combined in his designs. At first the two were layered: he'd put leaf forms on a spherical vase or branch forms on a lamp. But by the time he started building his masterpiece for Johnson Wax, the laws that rule geometry and those that govern growing things were fused in his designs.

The complex at Racine still looks machine-age modern. True, many of its rooms feel small, and its Pyrex tube-walls leaked for years, but these flaws no longer matter. Most machines are cold, dead things. This one feels alive.