Encyclopaedia Britannica Almanac 2009Archived 2014-09-22 at the वेबैक मशीन, pp. 121, Encyclopaedia Britannica, 2009, ISBN 978-1-59339-839-2, ... Also called summer time, daylight saving time is a system for uniformly advancing clocks, especially in summer, so as to extend daylight hours during conventional waking time. In the Northern Hemisphere, clocks are usually set ahead one hour in late March or in April and are set back one hour in late September or in October ... conserve fuel by reducing the need for artificial light ...
Encyclopaedia Britannica Almanac 2009Archived 2014-09-22 at the वेबैक मशीन, pp. 121, Encyclopaedia Britannica, 2009, ISBN 978-1-59339-839-2, ... Also called summer time, daylight saving time is a system for uniformly advancing clocks, especially in summer, so as to extend daylight hours during conventional waking time. In the Northern Hemisphere, clocks are usually set ahead one hour in late March or in April and are set back one hour in late September or in October ... conserve fuel by reducing the need for artificial light ...
