160 ROUGH WAYS MADE SMOOTH. 



arrount of work is done in the same space of time. But 

 here an important consideration has to be attended to. 



There are two things which the oarsman does in what- 

 ever style he rows. He propels the boat along, by pressing 

 the blade of his oar against the water as a fulcrum ; but he 

 also propels his oar more or less through the water. If 

 instead of the actual state of things, the boat were to slide 

 along an oiled groove in some solid substance, whose surface 

 was so ridged that the oar could bear upon the ridges with- 

 out any flexure, then indeed it would matter very little in 

 what way the oar was pulled, so long as it was pulled 

 through a good range in a short space of time. But the 

 actual state of things being different, we have to inquire 

 whether it is not possible that one style of rowing may serve 

 more than another to make the slip of the oar through the 

 water (a dead loss, be it remarked, so far as the propulsion 

 of the boat is concerned) bear too large a proportion to the 

 actual work done by the rower. 



Let us make a simple illustration. Suppose a person 

 standing on the edge of a sheet of water seeks to propel 

 across the sheet a heavy log lying near the bank. If he 

 gives the log a violent kick, it will scarcely move at all 

 through the water, but after a few vibrations will be seen to 

 lie a few inches from its former position. The force ex- 

 pended has not been thrown away, however, but has resulted 

 in a violent shock to the kicker. But if instead of kicking 

 the log the person apply the same amount of force gently at 

 first and then with gradually increasing intensity, the log will 

 receive a much more effective impetus, and its motion will 

 continue long after the force has ceased to be exerted. 

 The same amount of force which before produced a motion 

 of a few inches will now project the log several yards. 



And now to apply this illustration. If the object of the 

 rower were to move his oar through the water the boat 

 being supposed for the moment to be a fixture he could 

 not do better than to adopt the Cambridge style of pulling. 

 For this style gives a steady pressure on the oar at the be- 



