AND AGRICULTURE. 21 



a fine white powder. Boiled with fats, or oil, it 

 makes hard soap. (See Appendix, 8.) 



LIME is a well-known substance. It looks 

 like pieces of white earth. It is an alkali. 

 Lime-stone is burned in a kiln, and it is then 

 called quick-lime. When water is poured on 

 quick-lime, it slakes, becoming very hot, and 

 throwing off a great deal of steam. Slaked lime 

 is in the form of a white powder. It is used in 

 making mortar, which is a mixture of slaked 

 lime and sand. It has also a metallic base, 

 which is called calcium. Chalk, marble and 

 spar, are lime combined with other bodies, called 

 acids. Bones contain much lime, and so do oys- 

 ter and other shells. When bones and shells are 

 burned in a hot fire, their organic part is con- 

 sumed, and the inorganic part, or lime, remains 

 in the fire. Egg-shells are almost all lime. If 

 fowls cannot get lime, or something which con- 

 tains lime, their eggs are soft, and have no shell. 

 Lime is one of the most abundant things the 

 earth contains. (See Appendix, 9.) 



Questions. Boiled with fats, or oil, what does soda 

 make ? What does quick-lime look like ? How is it made ? 

 What effect has water poured on lime ? Name some of the 

 varieties of lime. "What is lime found in ? Is lime very 

 abundant ? 



