X 



SCIENCE ANlVXTHE PROPERTIES OF MATTER 5 



TABLE SHOWING THE ORDER OF 



Malleability Ductility Tenacity Infusibility 



Gold 



Silver 



Aluminum 



Copper 



Tin 



Lead 



Zinc 



Platinum 



Iron 



9. Indestructibility of Matter. While all forms of matter 

 may be changed or modified they can never be destroyed. 

 As an illustration, when sugar dissolves in water the particles 

 of sugar are so small or so minutely divided that they cannot 

 be seen. Yet they are not destroyed because they can be 

 recovered by boiling the water until it disappears in the 

 form of steam and leaves the particles of sugar behind. Or, 

 if wood or coal is burned and the ashes, vapors, and gases 

 that have come from it are collected and separated from the 

 gases of the air with which they have united during the pro- 

 cess of combustion, it will be found that the united mass of 

 the ash, gases, and vapors is the same as the mass of the 

 original piece of wood or coal. It is a fundamental principle 

 of science that matter is indestructible. 



Questions 



1. Is shop practice based upon any or many sciences? 



2. Is it sufficient to know only the practice of the trade to be 

 a successful mechanic? 



3. How will it assist a mechanic to know why he performs each 

 operation and uses each tool? 



4. Does the average mechanic explain his work in terms of 

 science? If he does not, explain the reasons. 



