cking--his technical expertise in electrical engineering. Together the two men spent endless hours experimenting. Although Bell formed the basic concept of the telephone--using a varying but unbroken electric current to transmit the varying sound waves of human speech--in the summer of 1874, Hubbard insisted that the young inventor focus his efforts on the harmonic telegraph instead. Bell complied, but when he patented one of his telegraph designs in February 1875, he found that Elisha Gray had patented a multiple telegraph two days earlier. Greatly discouraged, Bell consulted in Washington with the elderly Joseph Henry, who urged Bell to pursue his "germ of a great invention" --speech transmission.
             Back in Boston, Bell and Watson continued to work on the harmonic telegraph, but still with the telephone in mind. By accident on a June day in 1875, an intermittent transmitter produced a steady current and transmitted sound. Bell had proof of his 1874 idea; he quickly sketched a design for an electric telephone, and Watson built it. The partners experimented all summer, but failed actually to transmit voice sounds. That fall, Bell began to write the patent specifications, but delayed application; Hubbard finally filed for the patent on February 14, 1876, just hours before Gray appeared at the same patent office to file an intent to patent his telephone design. Bell's patent was granted on March 7, 1876, and on March 10, the first message transmitted by telephone passed from Bell to Watson in their workshop: "Mr. Watson, come here, I want you!"
             After a year of refining the new device, Watson and Bell, along with Hubbard and Sanders, formed the Bell Telephone Company in 1877. Be
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