224 FACTS AND THEOEIES. 



hold that changes of atomic position may result in 

 change of every property but mass. The lay mind finds 

 it impossible to conceive how a thing apparently so un- 

 important as a mere change in the position of the same 

 atoms should result in the exhibition of qualities so dif- 

 ferent. The chemist, I suspect, is in the same predica- 

 ment, but he knows that something has occurred, he can 

 think of nothing better than a change of position, a 

 change in atomic arrangement, and that must do service 

 until he can think of something more satisfactory. 



Another important office of theory is to aid in the dis- 

 covery of truth. Nature is a dumb oracle to all who do 

 not rightly question it, and to them its answers are only 

 monosyllabic, a yes or a no. But such answers given 

 to questions judiciously put may give an amount of in- 

 formation limited only by the skill and knowledge of 

 the questioner. 



We have all played a parlor game in which one is re- 

 quired to discover something thought of by the rest of 

 the company. He is to ask twenty questions which 

 must each be answered by yes, or no. One who plays 

 the game well, will quickly succeed, while a novice will 

 often fail. The former selects his questions so that 

 every time he asks one he narrows the field. 



" Is it on our planet ? " 



"Yes," tells him the thing thought of is not a 

 heavenly body. 



"Is it found in the Eastern Hemisphere?" "No," 

 confines him to the Western. 



"Is it in the Northern Hemisphere?" "No," tells 

 him not to look for it in North America. 



" Is it an organism of any kind ? " "No," throws out 

 all plants and animals. 



" Is it a solid ? " "No." Then it must be a fluid. 



"Is it water?" "Yes." But water is found every- 

 where. It must be some special form of water, probably 



ISO 



