Important Elements. 181 



life as it now exists would have been impossible 

 upon the earth. If there had been less hydrogen to 

 combine with the oxygen, or less nitrogen to mingle 

 with it, the air would have been so rich in this ele- 

 ment that combustion would have been uncontrolla- 

 ble. Had there been no potash, the majority of 

 land plants could have had no existence ; or if it had 

 been found in small portions here and there upon 

 the earth, what a scanty vegetation would have 

 existed? And as animals depend upon plants for 

 life, without this element as it now exists, land ani- 

 mals would be almost, if not entirely unknown. 

 M'jn probably could n< The same is true 



oi other elements, of which we are accustomed to 

 think but little. If no phosphorus were found upon 

 the globe, none of the higher plants could grow 

 and mature their seeds, none of the higher animals 

 could e\ 



The bone and brain of man must have this ele- 

 ment. Now it is easy for one who has never studied 

 this subject in the light of chemistry, geology, and 

 physiology, to think of the earth as a huge conglo- 

 meration of matter, supporting plants and animals, 

 and to suppose that it might have been very differ- 

 ent from what it now is, and still support them ; but 

 it is not so. The want of a single one of the abun- 

 dant elements, of oxygen or hydrogen, nitrogen, car- 

 bon calcium, phosphorus, or potassium, would have 

 left the earth a dreary waste. Any essential variation 

 in the quantity, or distribution, or chemical power of 

 any one of them, would have entirely changed the face 



