70 



SOILS AND PLANT LIFE 



Now place a handful of wheat, oats, or other seed in a 

 wide-mouthed fruit jar. Moisten them enough to cause 

 them to germinate. Carefully set a small open bottle of 

 clear limewater in the jar with the germinating seeds. 

 Fasten the hd of the fruit jar on securelJ^ Keep a close 



Fig. 21. 



The clear limewater becomes milky. 



watch from day to day. See the milky film form at the 

 surface of the limewater. Finally, the limestone may form 

 a thin crust like ice over the surface, or it may settle, 



carbon dioxide, CO;, is passed into limewater, it displaces the 

 water which is combined with the calcium oxide and unites with 

 this calcium oxide, itself. We then have CaO and CO2 combined, 

 and these form CaCOs. or limestone. 



CaO + CO2 = CaCOa 



