LECTURES. 



187 



SYLLABUS OF A COURSE OF LECTURES ON PHYSICS, 

 BY PROFESSOR JOSEPH HENRY, SECRETARY OF THE SMITHSONIAN INSTITUTION. 



PART FIRST. 



INTRODUCTION. 



(1.). Science, properly so called, is the knowledge of the laws of 

 phenomena, whether they relate to mind or matter. 



By mind we understand that which thinks, icills and is capable of 

 moral emotions — by matter- that which ajfecfs our senses — by the term 

 phenomena a collection of associated facts ; and by laio the relation 

 which pervades a class of facts, or a general fact in reference to the 

 order of succession or the method of production of the phenomena, 



(2.) So far as these laws have been discovered and developed, they 

 constitute the science of the present day. 



The study of the laws of the phenomena necessarily includes that 

 of the phenomena themselves. 



The mere description and classification of facts belong to Natural 

 History. — [Novum Organum.] 



The test of a knowledge of true science is the ability to predict what 

 will happen when the circumstances are known. 



(3.) General science is separated into two divisions corresponding 

 to the two great objects of thought, material and immaterial. 



The first is usually called physical science, and the second meta- 

 physical. The use of these terms is, however, conventional. The 

 phenomena of mind, as well as of matter, belong to nature, which 

 includes all existence, 



(4.) Physical science or natural philosophy, in the widest use of the 

 term, comprehends the laws of all the phenomena of external nature, 

 but in the progress of knowledge it has been found necessary to divide 

 it into various parts. 



It is first separated into the study of the laws of Organic and Inor- 

 ganic matter. 



The first comprehends Zoology and Botany, or the phenomena of 

 animal and vegetable life. 



The phenomena of inorganic matter are also considered under two 

 divisions. Celestial and Terrestrial. The first, w^iich also includes 

 some of the phenomena belonging to the earth, is called astronomy. 



The phenomena of terrestrial inorganic bodies are fartlier divided 

 into three parts, 



1, Geology, including mineralogy, which treats of the laws of the 

 arrangement and constitution of the masses which form the earth. 



