INTRODUCTION. 39 



consider that portion of the science of the Cosmos which con- 

 cerns the earth. As the history of philosophy does not con- 

 sist of a mere material enumeration of the philosophical views 

 entertained in different ages, neither should the physical 

 description of the universe be a simple encyclopaedic compila- 

 tion of the sciences we have enumerated. The difficulty of 

 defining the limits of intimately-connected studies has been 

 increased, because for centuries it has been customary to 

 designate various branches of empirical knowledge by terms 

 which admit either of too wide or too limited a definition of 

 the ideas which they were intended to convey, and are, 

 besides, objectionable from having had a different significa- 

 tion in those classical languages of antiquity from which they 

 have been borrowed. The terms physiology, physics, natural 

 history, geology, and geography, arose, and were commonly 

 used, long before clear ideas were entertained of the diversity 

 of objects embraced by these sciences, and consequently of 

 their reciprocal limitation. Such is the influence of long 

 habit upon language, that by one of the nations of Europe 

 . most advanced in civilisation the word " physic" is applied to 

 medicine, whilst in a society of justly deserved universal 

 .reputation, technical chemistry, geology, and astronomy, 

 (purely experimental sciences,) are comprised under the head 

 of " Philosophical Transactions." 



An attempt has often been made, and almost always in 

 vain, to substitute new and more appropriate terms for these 

 ancient designations, which, notwithstanding their undoubted 

 vagueness, are now generally understood. These changes 

 have been proposed, for the most part, by those \vho have 

 occupied themselves with the general classification of the 

 various branches of knowledge, from the first appearance of 

 the great encyclopaedia (Margarita Philosophical) of Gregory 

 Reiseh,* prior of the Chartreuse at Friburg, towards the close 



* The Margarita Philosophica of Gregory Reisch, Prior of the Char- 

 treuse at Friburg, first appeared under the following title: Epitome omnis 

 Philosophic, alias Margarita Philosophica, tractans de omni generi scibili. 

 The Heidelberg edition (1486), and that of Strasburg (1504), both bear 

 this title, but the first part was suppressed in the Friburg edition of the 

 same year, as well as in the twelve subsequent editions which succeeded 

 one another, at short intervals, till 1535. This work exercised a great 

 influence on the diffusion of mathematical and physical sciences, towards 



