14 



MATTER AND ITS MEASUREMENT 



cf. 171), standard thermometers for determining temperature (c/. 

 63), and standard pyrometers for determining higher temperatures 

 than the thermometer will measure. We can realize the value of this 

 work when we understand that the measurement of high temperatures, 

 for example, is necessary in such important industries as making glass, 



FIG. 13. 

 The Bureau of Standards. 



pottery, and illuminating gas, and in the preparation and working of 

 fche metals. Besides, the Bureau determines the strength of materials 

 such as wood, steel, and cement, the fuel value of coal, petroleum, etc., 

 as well as many other properties which the modern manufacturer 

 needs to know. 



16. Summary. Science is organized knowledge. It arranges ob- 

 jects into groups or classes and studies the changes that objects 

 undergo. 



