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The ancient Britons, increasingly dependent on agriculture, were obliged to
study the seasons. So they founded a school of insomniac scientists鈥攁nd
built them long barrows to calibrate the movement of the stars, and later,
henges of wood and stone for observing the Sun and Moon. These people were not
druids or religious mystics, argues the erudite John North in Stonehenge, but
accomplished mathematicians and astronomers who, long before the arrival of
written numbers, developed a sophisticated angular geometry. Published by The
Free Press, $35, ISBN 0684845121.