International Meridian Conference
On 11 October 1883, a convention of railroad executives met in Chicago and agreed to the implementation of five time zones in North America, using as a basis Greenwich Mean Time. Before the invitations to the Washington conference were sent out on December 1, the joint efforts of Abbe, Fleming and William Frederick Allen, Secretary of the US railways' "General Time Convention" and Managing Editor of the "Travellers' Official Guide to the Railways", had brought the US railway companies to an agreement which led to standard railway time being introduced at noon on 18 November 1883 across the nation. Although this was not legally established until 1918, there was thus a strong sense of "fait accompli" that preceded the Washington conference, although setting local times was not part of the remit of the conference.
Prime time
In North America, television networks feed their prime time programming in two blocks: one for the Eastern and Central time zones, and the other, on a three-hour tape delay, for the Pacific time zone, to their local network affiliates. In Atlantic Canada (including Newfoundland) as well as Alaska and Hawaii, there is no change in the interpretation or usage of “prime time” as the concept is not attached to time zones in any way. Affiliates in the Mountain, Alaskan, and Hawaiian zones are either on their own to delay broadcast by an hour or two, or collectively form a small, regional network feed with others in the same time zone.