PREFACE 



WITHIN the past few years distinct advances have been made in 

 the methods of teaching science. It is becoming more and 

 more widely recognised that the only scientific knowledge worth 

 having is that gained by individual observation and experience ; 

 and public examining bodies are one by one bringing themselves 

 in line with this sound educational principle by causing their 

 examinations to be more a test of familiarity with experimental 

 methods and results than of information acquired by reading. 

 The new regulations for the Matriculation Examination of the 

 London University, making an experimental knowledge of the 

 fundamental principles of physical and chemical science compul- 

 sory for every candidate, represent an advance in this direction. 

 Moreover, provision for such an introductory course in science is 

 made in the Junior Local Examinations of the Universities of 

 Oxford and Cambridge ; and pupil teachers in elementary schools 

 are now encouraged by the Education Department to take up a 

 course of elementary science having nearly the same scope as 

 that just introduced into the Matriculation Examination of the 

 University of London. 



The lessons in this volume follow the Matriculation Syllabus 

 of "General Elementary Science." It is distinctly stated in a 

 note prefixed to the syllabus that " In particular, the subjects of 

 the present syllabus will be treated wherever possible from an 

 experimental point of view. Candidates will be expected to 

 have performed or witnessed simple experiments in illustration 

 of the subjects mentioned in this syllabus." With these require- 

 ments in mind, we have made experimental work a distinctive 

 feature of the book. A large number of simple and practicable 

 experiments, which, with a few exceptions, can be easily per- 

 formed by the individual student, are described ; and bur object 



