• U.S.

Art: From Pile to Pull

2 minute read
TIME

What makes architecture modern? Writing in the current Harper’s, Architect Harrison Gill, 56, of Chattanooga, Tenn., answers his own question with one word: “Tension.” Writes Gill:

“Transparent glass enclosures such as the United Nations . . . can be built only because materials in tension rather than walls bear the load of the building. [The] basic structural qualities [of building materials] are only two: resistance to compression and to tension stresses … In all architecture before our time, only the compression strength of materials was taken into consideration. Rocks like granite and basalt were the strongest, and great feats were performed with marble, limestone, sandstone, travertine, and even with manmade stones—burnt brick and mass concrete . . . The builders who used the arch . . . merely carried the use of materials in compression to its ultimate capability . . .

“It was not until the middle of the 19th century that builders fully understood and applied the use of steel in tension on a calculated basis . . . Roebling began to hang the Brooklyn Bridge on a spider web of steel cables in 1868 . . . Major William LeBaron Jenny designed the first true steel-frame building in Chicago in 1883 . . . In the spring of 1896, Frank Lloyd Wright built a wooden windmill tower at Spring Green, Wis. It was slender and 60 ft. high, built of two-by-fours and wood sheathing anchored to a heavy stone foundation. The lightweight wood construction was designed in perfect tension balance, and it has withstood the storms for over half a century, far beyond the life of steel windmills built at the same time . . .

“As we enter the Age of Tension, man . . . comes closer in his methods of building to the forces and mechanics of nature than ever before. The oak tree holds its own against the gale only because its roots are strong enough to resist the pull of the wind, and the fibers of its branches restrain the buffeting with their tautness . . . All living things exist in a state of constant tension; only the inanimate and the dead rest in place by weight alone, rock piled on rock and slab leaning against slab. All truly modern building is alive.”

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