Brief history of the telephone in Oxford
The following article about the introduction of the telephone to Oxford appeared in Jackson's Oxford Journal on 26 January 1878:

Timeline
1877: Oxford’s first two telephones were installed, with lines from the Telegraph Office in Mill Street, Osney to (1) the Post Office, which was then still at the Old Town Hall in St Aldate's and (2) 48 Cornmarket Street, the home and shop of the cutler George J. Neill who was the engineer to the Oxford Volunteer Fire Brigade, who had a line to the Fire Brigade office in New Inn Hall Street
1879 (September): The Edison Telephone Company gave notice in Jackson’s Oxford Journal of its intention to open a telephone exchange in Oxford, but it appears not to have had enough response to make the enterprise worthwhile
1885: By 17 October the reservoir-keeper's cottage at Headington had been connected by telephone to the pumping station at Hinksey, enabling the level of water to be regulated.
1886: The South of England Telephone Company Ltd opened Oxford’s first exchange at 54 Cornmarket Street
In March that year it was proposed to establish telephonic communication between the lodges of all the Oxford colleges, but there were protests against disfiguring Oxford by a system of overhead wires.1889: There were 55 telephone subscribers in Oxford
1890: The South of England Telephone Company was taken over by the National Telephone Company
1895: A second Exchange, the Post Office Trunk exchange, opened in Oxford, and the National Telephone Company moved to an upstairs room over the ‘Domestic Bazaar’ at 5 and 6 Magdalen Street
There were now 95 telephone subscribers in Oxford (see list below)1899: There were 111 telephone subscribers in Oxford
1912: The Post Office Trunk Exchange took over the National Telephone Company
1923: A new central Oxford telephone exchange opened in Pembroke Street
1924: There were 1,090 telephone subscribers in Oxford
1928: Cowley and Headington exchanges opened
1929: Summertown telephone exchange opened
1934: There were 1,987 telephone subscribers in Oxford
1959: New exchanges at Oxford and Headington were opened
1963: STD (Standard Trunk Dialling) services started in Oxford
1977: There were 11,520 telephone subscribers in Oxford
For further information, see R. A. J. Earl, The Development of the Telephone in Oxford, 1877–1977 (The Post Office, 1978)
Transcribed telephone directory for Oxford in 1895
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