Science and technology in the United States finish. For example, the British engineer Joseph Swan built an incandescent electric lamp in 1860, almost 20 years before Edison. But Edison's light bulbs lasted much longer than Swan's, and they could be turned on and off individually, while Swan's bulbs could be used only in a system where several lights were turned on or off at the same time. Edison followed up his improvement of the light bulb with the development of electrical generating systems. Within 30 years, his inventions had introduced electric lighting into millions of homes. Another landmark application of scientific ideas to practical uses was the
World's Columbian Exposition their costs at $554,000 but Westinghouse under bid them by 70 cents per lamp to get the contract. Westinghouse could not use the Edison incandescent lamp since the patent belonged to General Electric and they had successfully sued to stop use of all patent infringing designs. Since Edison specified a sealed globe of glass in his design Westinghouse found a way to sidestep the Edison patent by quickly developing a lamp with a ground glass stopper in one end, based on a Sawyer-Man "stopper" lamp patent they already had. The lamps worked well but were short lived, requiring a small