20 SIMPLIFIED SCIENTIFIC ASTROLOGY
in width (this being the distance the Sun travels in one hour), and all the clocks in each division set to one uniform time, gauged by a meridian located in the middle of the resulting time-zone, confusion of travelers would be avoided.
Accordingly America was divided into four such zones by three imaginary lines, as illustrated in the diagram,
In the Eastern Time Zone clocks are set true to the 75th meridian, 5 hours earlier than Greenwich Mean Time.
In the Central Time Zone time is regulated to the 90th meridian which is 6 hours earlier than Greenwich.
In the Mountain Time Zone timepieces are governed according to the 105th meridian, 7 hours earlier than Greenwich Mean Time,
In the Pacific Time Zone time is standard to the 120th meridian, 8 hours earlier than Greenwich.
(There is a fifth zone in the far East, comprising Maine, Nova Scotia, etc. This zone we omitted in order that our diagram might be larger.)
In all cities located on these Standard Meridians (see diagram on the opposite page), such as Philadelphia and Denver, standard time is also true local time, and no correction is required in calculation of horoscopes. But Detroit, which you will see located on the dividing line between the Eastern and Central Time Zones, is 7 degrees east of the 90th meridian,