XV 



THE ATMOSPHERE 



221 



EXPT. 215. Fit a delivery tube B to a flask A, and in the 

 flask put a mixture of potassium chlorate and manganese 



FIG. 111. Preparation of Oxygen. 



dioxide. Let the end of the delivery tube dip under water 



contained in the trough C. Fill 

 invert them in the trough. Heat 

 the flask, and when the gas is 

 being evolved place the mouth 

 of the jar D over the end of the 

 tube so that the gas displaces the 

 water. When all the jars are 

 full take out the delivery tube 

 from the water, and leave the 

 flask for further examination. We 

 must now examine the gas. Its 

 action upon burning wood has 

 been seen before. 



EXPT. 216. First jar. In this 

 plunge a piece of red-hot charcoal 

 placed in a deflagrating spoon (a 

 small upturned iron spoon with a 

 long handle) (Fig. 112). Note the 



brilliancy of the combustion. Now 



J . 



pour into the jar some clear lime- 



five jars with water and 



FIG. 112. Jar with Deflagrating 



Spoon in it. 



