The Cooper Hewitt Smithsonian Design Museum is housed in the former home of Andrew Carnegie, built in The sixty-four- room mansion is a fascinating study in innovative design – it was the first private residence in the United States to have a structural steel frame and one of the first in New York to have a residential Otis passenger elevator.

Andrew Carnegie, who arrived in the United States from Scotland at age 13, became a steel industrialist and philanthropist, and one of the nation's richest men. His empire included coal mines, steel mills and steamship and rail lines. He had this 64-room brick mansion, which he intended to be "the most modest, plainest and roomiest house in New York," built after his retirement in From the house he devoted the rest of his life to philanthropy, in particular the establishment of public libraries across the nation. For decades Carnegie had insisted on the most technologically advanced equipment for his steel mills, and he demanded the same for his new home. The house was a marvel of modern technology. Outside air was brought in and heated or cooled to the desired temperature. In the sub-basement, a miner's cart carried coal along a railroad track from a massive bin to three large boilers. On a typical winter day, it took two tons of coal to heat the house. If the basement's technology shouted Carnegie, the walls of his library-study did the same. Running around the walls of the room were the slogans that had inspired him throughout his life: "Let There Be Light," "The Kingdom of Heaven Is Within You," "The Gods Send Thread For The Web Begun," "All Is Well Since All Grows Better," and "Thine Own Reproach Alone Do Fear." It was here that Carnegie sat at his giant desk-so huge it had to be built in the room-and contemplated how best to dispose of his wealth.

Foyer and grand staircase

The first residential structure to employ a steel framework, the Carnegie house was a wonder of up-to-date technology. A central heating and cooling system brought air in from the outside, filtered it, heated or cooled it and adjusted the humidity. A filtering system purified the drinking water. Two huge boilers provided steam heat to the main house, two smaller ones heated the conservatory, and yet another provided hot water for bathing, dish washing, etc. In the basement, a miniature railroad transported fuel from the coal bin to the boilers. On a typical winter day two tons of coal would be consumed to heat the mansion. And although Carnegie's drink of choice was Dewar's scotch, the basement included a 1500-bottle wine cellar. For years the Carnegies lived happily with their 20 servants at 2 East 91st. From his huge desk, so large it had to be constructed inside the office, Andrew Carnegie gave away around $350 million -- over $60 million of which went for the establishment and construction of Carnegie Libraries around the country.

IN THE PROCESS LAB: POCKET BRAINSTORM TRY IT! Sketch a design that combines two items from your pocket or backpack