Jeremy Ackerman, Oliver Barrett, Margaret Blackburn, Lottie Child, Sacha Craddock, Dan Davis, John Dougal, Marianne Eigenheer, Alan Frienkel, James Graham, Cora Hemming, Sebastian Horsley, Dominic Kelleher, Nikos Kostavos Jeff Logsdan, Giuseppe Mascoli, Ian Morris, Paddy O’Connor,, Will Palin, James Putnam, Valentina Scambia, Yuu Takehisa, JJ Xi, Sylvia Ziranek

Water

From ancient times it has been known that there was some connection between the daily rise and fall of the sea-level round the coast which we call the tides and the Moon. It was not till the time of Newton, however, that the explanation of this connection was discovered. He showed that gravitation was a mutual attraction between all the particles of matter in the universe, and that not only does the Earth attract the Moon but the Moon attracts the Earth. The tides form the most constant and regular movement of the waters of the sea. Twice every day, as we know, the edge of the sea rises and falls. As a matter of fact this rise and fall of the ocean occurs twice every 24 hours and 52 minutes, and that is why high tide and low tide, the highest and lowest points reached by the water, do not occur at the same time every day. When the tide is rising it is called flood tide, and when it is falling it is known as the ebb tide. 

The approximate regularity of the tides and their coincidence with certain movements of the Moon soon set men thinking that one fact must have a bearing on the other. The tides, it was seen were highest when the moon was either new or full, and at full moon the interval between the time of high tide and the time when the Moon is on the meridian is approximately constant for each place. In other words, the time of high water is related to the passing of the Moon across the meridian. But it is not the Moon alone that attracts the waters on the face of the Earth. The Sun also draws the ocean- surface outward, though owing to its immense distance the Sun’s influence is only about one-third that of the Moon.