270 SCIENTIFIC ILLUSTRATIONS [Pil 



the solids of the globe cannot for a moment be exposed even to 

 water or to the atmosphere without becoming liable to change. 

 They instantly begin to wear down. The adamantine rock is 

 no accurate symbol of rest, for it is subject to the law of 

 change. VE. 



Pertinacity Rewarded. 



The fox, being extremely fond of honey, often attacks nests 

 of wild bees. When the bees rush out and sting him he rolls 

 on the ground and crushes them, and returns to the charge so 

 often that he forces them at length to abandon the hive from 

 which he extracts both the honey and the wax. R. 



Alteration of Physical Agents would be 

 Catastrophic. 



The physical agents which do not vary are the same in all 

 climates. Their influence, which is so permanent, seems also to 

 be so necessary that were any one of them to be altered, the 

 whole living machinery of the earth would stop, from the ani- 

 malcule to the whale, and from the byssus to the oak. If water 

 were to become solid at 100 instead of at 32, no living being 

 as now constituted could exist. If gravity were diminished on 

 the earth, a thousand inconveniences would be felt by all, and 

 though we do not see any reason why life should cease at once, 

 as in the former instance, still the amount of inconvenience 

 would be enormous and intolerable. Thus if it were suddenly 

 reduced to the force which it exerts on some of the ultra- 

 zodiacal planets, as Ceres and Pallas, a man, says Herschel, could 

 spring with ease sixty feet high, and sustain no greater shock 

 on coming to the earth than he does now from leaping a yard. 

 Giants might exist, and that enormous animal the whale, which 

 now requires the buoyant power of water to counteract its 

 weight, might then be a denizen of the land. s. 



Pilgrim Natures. 



In the arid deserts of Central South America there is a 

 strange plant, the Selaginella convoluta, a species of club moss, 



