Frank Osborne (California politician) explained

Frank P. Osborn was an American politician and the mayor of Alameda, California. In 1951 he was the recipient of the first long-distance phone call to use the direct distance dialing telephone facility, dialed by Mayor M. Leslie Denning of Englewood, New Jersey.^{[1] [2]}

Osborn served two terms as mayor. He sat on the city council between 1943 and 1953.^[3]

Notes and References

1. https://books.google.com/books?id=ar0HyeVKeY4C&dq=Mayor+M.+Leslie+Denning&pg=PA1 The mosquito crusades: a history of ... - Gordon M. Patterson - Google Books
2. http://www.corp.att.com/attlabs/reputation/timeline/51trans.html 1951: First Direct-Dial Transcontinental Telephone Call
3. News: 'Deteriorization' of Golf Course Hit . 10 November 2023 . Oakland Tribune . 3 November 1965.