OF NATURAL PHILOSOPHY. 221 



PART III. 



OF THE SUBDIVISION OF PHYSICS INTO DISTINCT 

 BRANCHES, AND THEIR MUTUAL RELATIONS. 



CHAPTER I. 



OF THE PHENOMENA OF FORCE, AND OF THE CONSTI- 

 TUTION OF NATURAL BODIES. 



(232.) NATURAL HISTORY may be considered in 

 two very different lights: either, 1st, as a collection 

 of facts and objects presented by nature, from the 

 examination, analysis, and combination of which we 

 acquire whatever knowledge we are capable of attain- 

 ing both of the order of nature, and of the agents she 

 employs for producing her ends, and from which, 

 therefore, all sciences arise ; or, 2dly, as an assem- 

 blage of phenomena to be explained ; of effects to 

 be deduced from causes ; and of materials prepared 

 to our hands, for the application of our principles to 

 useful purposes. Natural history, therefore, con- 

 sidered in the one or the other of these points 

 of view, is either the beginning or the end of phy- 

 sical science. As it offers to us, in a confused and 

 interwoven mass, the elements of all our knowledge, 

 our business is to disentangle, to arrange, and to 

 present them in a separate and distinct state: and 

 to this end we are called upon to resolve the important 

 but complicated problem, Given the effect, or as- 



