2 MATTER AND ITS MEASUREMENT 



grouped as flowering or non-flowering plants, and each of 

 these will have many divisions. To take one illustration : 

 the daisy, the dandelion, and the sunflower belong in one 

 great group of flowering plants because the structure of 

 their flowers is similar, while the rose, the strawberry, 

 and the apple belong in an entirely different group. 



But the classifying of objects, while very valuable, is 

 only a part of science. By far the greater part is taken up 

 with the study of the objects themselves. We want to 

 know their beginning, or origin, what they do, and what 

 becomes of them. For the objects of nature are always 

 changing. Living things grow, and then decay; rocks 

 are made, and then crumble. Even the "eternal hills" 

 are worn away, and the "fixed" stars appear to be fixed 

 only because, to the eye, they change their positions so 

 slowly. 



2. Phenomena. By a "phenomenon" (plural, phe- 

 nomena) we mean simply a happening, a change, that takes 

 place in some object. It is not necessarily a strange 

 occurrence, like the appearing of a comet or an eclipse. 

 We observe a phenomenon when we see a marble roll over 

 the floor, when an apple falls to the ground, when a com- 

 pass needle takes a north and south position, when an 

 electric light is "turned on" or "goes out." Other phe- 

 nomena are such common changes as the burning of wood, 

 the souring of milk, the freezing of water, and the rusting 

 of iron. 



3. The Scientific Way, or Method. Primitive man 

 probably reasoned in a very childish way about objects 



