SOLUTION AND CRYSTALLIZATION >'- '- 



For study of how roots act in different kinds of soils use the 

 glass frames used for seed-planting. Pack the clay well. 



What gives the dark shades of color to the soil? Where a ditch 

 or other cut in the surface of the soil shows a section, note that 

 the upper part is of a darker shade than the lower; sometimes it 

 is quite black. Take a portion of such soil, and in a crucible (a big 

 spoon will answer) in an open fire burn the soil thoroly. The 

 dark color will disappear. It was due to partially decomposed 

 vegetable (rarely animal) remains, that is, of roots, stems, leaves, 

 etc. , and the fire has burned this organic matter away. This dark 

 layer is sometimes called loam, while the brighter colored soil 

 beneath is called the subsoil. 



Experiments With Ice. 

 FROST. 



The method of making ice-cream has already taught most 

 children that salt and ice make a freezing mixture. To show by 

 its means the formation of frost, fill a tin cup, or other similar 

 metal vessel, with a mixture of salt and pulverized ice. Stir the 

 mixture. Soon the sides of the vessel will be covered over with 

 moisture condensed from the air. As the vessel further cools, this 

 moisture is frozen, and the vessel becomes covered with a coating 

 of frost. Press the tips of the fingers firmly against the frosted area 

 until the small space thus covered is melted. Remove the fingers 

 and watch the formation of the frost crystals as the film of water 

 freezes. 



The temperature of melting or forming ice is 32 F. This 

 can be determined by the thermometer in a vessel of melting ice 

 or in a vessel in which water is made to freeze. The latter can be 

 accomplished b}' surrounding a small vessel of water with the ice 

 and salt mixture. As long as any of the water remains unfrozen, 

 it does not sink below 32. 



