PREFACE 



A science, as the term is usually employed, implies a group- 

 ing of the facts and phenomena of some one field of human 

 knowledge according to certain general statements known 

 as theories and laws. Botany, for instance, is a classification 

 of man's knowledge of plants, and of the conditions for their 

 growth. It makes possible the study of plants in groups rather 

 than one by one. 



But in General Science as a high school subject selections of 

 topics for study are made from any and all of the secondary 

 school sciences. These topics are studied for the general 

 purpose of giving scientific explanations to whatever affects 

 daily life in so far as they lend themselves readily to elemen- 

 tary scientific discussions. Some theory is given as needed 

 in these explanations, but there is little or no regard to 

 whether the facts and explanations have to do with any one 

 science or another. Sufficient experimental phenomena are 

 to be provided in laboratory exercises and classroom demon- 

 strations. The topics are supposed to be more or less familiar 

 through the common experiences of childhood and youth, 

 and of such a nature as to foster a scientific spirit. 



This text seeks to relate for schoolroom uses the teachings 

 of science and the common experiences of life. Its dis- 

 cussions are designed to stimulate a desire on the part of 

 pupils for information concerning everyday phenomena 

 readily obtainable from high school science texts, and from 

 reference books suited for use in elementary science teaching. 



Some of the discussions of the text though elementary in 

 character will present difficulties for beginners. But the 



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