On The Origins Of Knowledge Of The Sea Tides From Antiquity To The Thirteenth Century
This is an exhaustive survey of the first written records concerning sea-tides and hypotheses for their cause, covering a period from 500 B.C.E. to 1250 C.E. Seamen of antiquity must have gained practical knowledge of tides by experience, but they left no written record. Despite some early Greek references to the subject, the Hellenic civilisation knew little about tides until the reports of travellers like Pytheas and Posidonius (135-51 B.C.E.), Many of the first informed writings are now lost but their gist is known to us, allowing for personal bias and distortion, through Geography by Strabo (ca. 63 B.C.E.-ca. 25 C.E.). Arab astrologers were impressed by the evident relationship to the Moon; they wrote seminal treatises, later translated and copied widely in western Europe. Nevertheless, some non-lunar hypotheses from Greek poetry, involving ocean currents, undersea caverns, and whirlpools, survived through translations for many centuries. During the Medieval period knowledge in Europe was preserved by Christian monks and extended by their observations. Meanwhile, understanding in China developed to the construction of the first known tide-table for predicting the times and heights of a tidal bore, around 1000 C.E.