PREFACES TO THE FIRST AND SECOND EDITIONS, 



ABRIDGED. 



In tracing the progress of knowledge, we may frequently observe 

 that the cultivation of particular branches of science, at certain peri- 

 ods, was determined by causes which had little connection with their 

 intrinsic utility. Fashion, caprice, and the authority of eminent 

 names, govern mankind in philosophy, as well as on all other sub- 

 jects. But, independently of accidental causes, there are leading ob- 

 jects in the universe, which, as nations advance in civilization, seem 

 naturally to direct their attention to certain sciences in succession. 

 The brilliancy of the sun, moon, and planets, their various motions, 

 and connection with the changing seasons, would first arrest the at- 

 tention of the rude philosopher ; nor need we wonder that he soon 

 began to regard them as endowed with life and intelligence, and attri- 

 buted to them a mysterious power over human affairs: thus the heav- 

 enly orbs became the objects of religious adoration ; and curiosity, 

 hope, and fear, lent their aid to the early cultivation of astronomy. 



Mathematics and mechanical philosophy are so intimately connect- 

 ed with astronomy and the most useful arts, that they naturally claim- 

 ed the second place among the early sciences. 



The branches of philosophy which comprise a knowledge of the 

 physical qualities of matter, or such as are perceptible by the sen- 

 ses, follow next ; and at a later period, chemical philosophy, or that 

 science which endeavours to ascertain the elementary substances, of 

 which all material objects are composed. In the order of succes- 

 sion, mineralogy and geology are the last of the natural sciences ; 

 for though an acquaintance with the earth is more important to man, 

 than a knowledge of the distant parts of the universe, yet, previous- 

 ly to the cultivation of the other sciences, and of chemistry in partic- 

 ular, our knowledge of the mineral kingdom could not extend much 

 beyond that of the rudest periods. Thus we find, that notwithstand- 

 ing the precious metals, and many of the mineral treasures which the 

 earth contains, have been the objects of insatiable cupidity in every 

 age, yet, till the present day, almost all that was known of mineralo- 

 gy was confined to uneducated working miners. 



In looking over the pages of history we may observe, that the most 

 polished nations of antiquity had scarcely advanced beyond a limit- 

 ed acquaintance with astronomy, geometry, and mechanical philoso- 

 phy. In modern Europe, all the natural sciences, geology and min- 

 eralogy excepted, have been successfully cultivated, and their pro- 

 gress has been astonishingly rapid ; but till about the middle of the 

 last century, the structure of the earth had scarcely engaged the at- 

 tention of philosophers. Near that time, Lehman, the German, first 

 observed that there are certain rocks which occupy the lowest rela- 

 tive situation in different countries, and that these rocks contain no 

 organic remains : hence he gave them the name of primary, and es- 

 tablished a division between them and the rocks by which they are 



