Preface

The origin of sundials is lost in antiquity. The student of the history of science finds in them evidence of very early understanding of fundamental relationships of astronomy. The modern science teacher uses them to illustrate vividly the first principles of the solar system. The artist finds examples of medieval design and craftsman-ship in their intricate engraving or stonework. The architect uses them to good advantage to grace public building, and the landscape architect finds few things more suitable as accents for a formal garden.

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Historical SketchFortunately we need not start by defining time, since the concept has perplexed philosophers and lexicographers and served as the basis for learned and inconclusive arguments. We shall assume, with the man in the street, that we know what time is, that we know what time it is, and that our problem is measuring it rather than defining it.