THE ELEMENTS 



OP 



LABOBATOBY WOEK 



CHAPTER I 



MEASUREMENT OF QUANTITY OF MATTER 



1. To Find Equal Quantities of Matter. 1. Use a balance, 

 and counterpoise two pieces of wood, cutting away one or the 

 other with a knife until exact balance is obtained. 



2. Counterpoise a piece of wood and a piece of lead. 



3. Counterpoise another piece of wood with the lead, and 

 then observe that the two pieces of wood counterpoised by the 

 lead counterpoise one another. 



The above exercises show : 



1. That with the same kind of matter, wood, the pieces 

 which counterpoise each other are the same size, or there- 

 abouts ; but different kinds of matter which counterpoise each 

 other are not of the same size. 



2. That two bodies counterpoise each other if they each 

 counterpoise a third body ; for these two bodies have been 

 found to act alike under the same conditions that is, when 

 placed in the same position, and with all the surroundings the 

 same. 



Two such pieces of matter are said to be equal quantities 



B 



