<p>We are so familiar with the restlessness of the sea, and with the havoc which it works on our shipping and our coasts, that we need no demonstration to convince us that waves can carry energy from one place to another. Few of us, however, realise that the energy in the sea is as nothing compared with that in the space around us, yet such is the conclusion to which we are led by an enormous amount of experimental evidence. The sea waves are onl...