Time and Tide

Time and Tide, A Romance of the Moon, is a book of two lectures delivered in the theatre of the London Institution, on the afternoons of November 19 and 26, 1888, by Sir Robert S. Ball. The book is dedicated to the Members of the London Institution. The speaker says that the tidal efficiency of the sun is less than half that of the moon. The text says that when the solar tide and the lunar tide are acting in unison, they conspire to produce very high tides and very low tides, or spring tides.

The speaker says that the tides really owe their origin to the fact that the tide-producing agent operates more powerfully on those parts of the tide-exhibiting body which are near to it than on the more distant portions of the same. The speaker mentions Professor Fitzgerald's address to the British Association at Bath last autumn, in which he gives an account of those astounding experiments of Hertz. The speaker feels that in the progress of these two lectures only the merest outline of the theory of tidal evolution in its application to the earth-moon system has been given.