Two years after Alexander Graham Bell patented his telephone in 1876, Connecticut's New Haven District Telephone Company issued the first telephone book in the United States. It was, in fact, just a single sheet of paper. The names of 50 telephone owners were listed, but their actual phone numbers weren't included because switchboard operators were expected to connect the callers. This "list of subscribers," dated 21 February 1878, listed residences, physicians, dentists, stores, and markets in the area that had telephones. Later that year, a longer New Haven phone book was published, which also included advertisements.
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