8 HALF AN HOUR WITH THE WAVES. 



as a rule, the waves are low in the latter they are 

 high. It has been advanced recently, and by some 

 of our best mathematicians, that the drag on the 

 revolving of the earth on its axis, caused by the 

 tides, must in the long run act as a break, so as to 

 render the rate of revolution slower. In other 

 words, to lengthen our days and nights. There can 

 be little doubt that this is actually the case, and 

 that, in some remote period, if the retardation goes 

 on, it will end in the earth ceasing to revolve, or 

 doing so at a much slower rate than at present. If 

 this be the case, then, in the earlier geological 

 epochs, the revolution of the earth on its axis must 

 have been more rapid than at present ; and this 

 may have affected geographical changes, and even 

 the conditions of animal and vegetable life, in a way 

 of which we can now form no conception. 



The waves or billows produced by these various 

 disturbing agencies of tides, currents, and winds 

 exercise a marvellous influence on the condition of 

 the atmosphere. The force liberated as they dash 

 over each other, or spend themselves against the 

 shore, must be immense, and more than one earnest 

 physical philosopher is turning his attention to the 

 inquiry as to whether such force cannot be utilised for 

 the service of mankind ! We know that 'nothing is 

 absolutely wasted that the mechanical motion of the 

 waves thus suddenly arrested is converted into heat, 

 electricity, &c. One cannot wonder, therefore, that 

 the sea-air should be distinguished for the peculiar 



