34 



Domestic Science 



in a room is usually expressed in cubic feet or cubic 

 metres ; the amount of material required to build a 

 dam is given in cubic yards or cubic metres. 



When dealing with the interior volume, or " capa- 

 city ", as it is termed, of measuring vessels, an entirely 

 different set of units is made use of in Britain. We 

 ask for a pint or a quart of milk, not for a certain number 

 of cubic inches of that fluid. No simple relation exists 

 between the cubic inch and the pint, 1 pint containing 

 34*66. . . cubic inches. In the Metric System the unit of 

 capacity is known as the "litre", and in this case 

 there is a very simple relation between the ordinary 



Fig. 11. 



unit of volume and that of capacity, since 1 litre is 

 exactly 1 cubic decimetre. It will be readily seen, 

 therefore, that the measurement and comparison of 

 volumes, when using the latter system, is much more 

 easily carried out than is the case with the British 

 System, thus emphasising what has already been 

 written under this head when dealing with the measure- 

 ments of length and area. 



The comparative sizes of the cubic inch and the 

 cubic centimetre are shown in Pig. 11. 



