242 COSMICAL ARRANGEMENTS. 



violent bodily motions, to running, leaping, pull- 

 ing or pushing objects, it is easily seen how 

 entirely we depend upon the friction of the 

 ground for our strength and force. Every one 

 knows how completely powerless we become in 

 any of these actions by the foot slipping. 



In the same manner it is the friction of objects 

 to which the hand is applied, which enables us 

 to hold them with any degree of firmness. In 

 some contests it was formerly the custom for the 

 combatants to rub their bodies with oil, that the 

 adversary might not be able to keep his grasp. 

 If the pole of the boatman, the rope of the sailor, 

 were thus smooth and lubricated, how weak 

 would be the thrust and the pull ! Yet this 

 would only be the removal of friction. 



Our buildings are no less dependent on this 

 force for their stability. Some edifices are 

 erected without the aid of cement : and if the 

 stones be large and well squared, such structures 

 may be highly substantial and durable ; even 

 when rude and slight, houses so built answer the 

 purposes of life. These are entirely upheld by 

 friction, and without the support of that agent 

 they would be thrown down by the Zephyr, far 

 more easily than if all the stones were lumps of 

 ice with a thawing surface. But even in cases 

 where cement binds the masonry, it does not take 

 the duty of holding it together. In consequence 

 of the existence of friction, there is no constant 

 tendency of the stones to separate ; they are in a 



