94 G. K. Gilbert—The Colorado Plateau Province. 
without quitting the bottom. And finally there is a limit to 
the power of every current, and the largest fragments of its 
bed are not moved at all. 
the time occupied in their transportation. Since fine particles 
sink more slowly than coarse, the same consumption of energy 
will convey a greater load of fine than of coarse. 
mum load of detritus of the given size. But fine detritus 
quires less velocity for its transportation than coarse, and is 
not so soon reduce the current to the limit of its efficiency. 4 
greater per cent of the 
ey by fine detri 
energy 
and on the other, it ¢ 
energy. 
