The dwellers in the soil 



59 



of a pint of boiling water, pour into each of three saucers, 

 and cover over with plates. Then stir up some baked 

 soil in a cup half full of cold boiled water, and quickly 

 put a teaspoonful of the liquid into a second cup, also 

 half full of cold boiled water. Stir quickly and put 

 a spoonful on to the jelly, tilting it about so that it 

 covers the whole surface and label the saucer "baked 



A B 



Fig. 27. 



Bottle containing lime water, used 



to show that breath makes 



lime water milky 



soil." Do the same with the "unbaked soil," labelling the 

 saucer; leave the third jelly alone and label it "un- 

 touched." Cover all three with plates and leave in a 

 warm place. After a day or so little specks begin to 

 appear on the jelly containing the unbaked soil, but 

 not on the others (Fig. 26) ; they grow larger, and before 

 long they change the jelly to a liquid. The other jellies 



