STATES OF AGGREGATION. 



17 



air-holes c are too large ; but if they are too small, the flame is 

 yellow and not blue. For regulating the size of the air-holes a 

 rnoveable ring, fig. 19 c, is used ; it has corresponding holes to 

 those in the tube, which in different positions may be used either 

 for fully admitting or for partially shutting off the air. 



Fiu. 19 (| real size}. FIG. 20 ( real size). 



There are many bodies like atmospheric air, which 

 are called gases. Such bodies are therefore distinguished 

 as gaseous or aeriform bodies. 



Numerous bodies are capable of assuming each of 

 the three different states which have been considered. 

 Thus water, which ordinarily is a liquid, becomes ice, a 

 solid) in the cold, and steam, a gas, if sufficiently heated, 

 These three states, in which bodies occur, are called 

 their states of aggregation. The distinguishing charac- 

 ters of these states are briefly : 



SOLID bodies. Definite Shape. Definite Volume, 



LIQUID bodies. Indefinite Shape. Definite Volume. 



GASEOUS bodies. Indefinite Shape. Indefinite Volume. 



