LESSON ELEVEN 
HOW DO HORSES MOVE? 
1. Plants and animals.—One important distinction be- 
tween higher plants and animals is that while plants are 
rooted to the ground, animals move freely about through 
a power that exists within them. No such power exists 
in plants. Mankind has taken advantage of this power 
for its own advancement. It exists in the horse in a high 
degree. Without animals man could never have ad- 
vanced beyond the stage of barbarism. America was not 
developed as was Europe because the Indian did not have 
the horse and the ox to assist him. 
2. Crowbar.—If one wishes to move a large bowlder, 
he places one end of a crowbar under the edge of it and 
then places a small stone under the crowbar. He next 
presses down on the upper end 
of the bar. What happens is 
that he increases his power at 
the expense of speed. If the 
upper end of the crowbar is ten 
times as long as the lower arm, 
ten times as much power will 
be exerted. At the same time, 
the hands of the person moving the bar go ten times as 
far as the stone which he moves. This is an absolute 
law. Increased power cannot be obtained without loss 
of speed and increased speed cannot be obtained without 
a corresponding loss of power. A horse of great speed 
cannot be a horse of great power. Powerful draft horses 
cannot be fast horses. A horse for general utility can 
have both power and speed only in fair degree. 
106 
— = SS aa 
CROWBAR INCREASES POWER 
