FINAL CAUSES. 



the traveller is often refreshed by the appearance 

 of a few hardy plants, which find sufficient ma- 

 terials for their growth in these arid regions : 

 and in the realms of perpetual snow which sur- 

 round the poles, the navigator is occasionally 

 startled at the prospect of fields of a scarlet hue, 

 the result of a wide expanse of microscopic ve- 

 getation.* 



But whatever charms the naturalist may find 

 in the occupations in which he is engaged, and 

 however wide may be the field of his exertions, 

 they still are insufficient to satisfy the more 

 enlarged curiosity of a philosophic mind. The 

 passive emotion of astonishment, in which in- 

 ferior intellects are content to rest, serves but to 

 awaken, in him who has learned to think, a 

 desire of further knowledge. Filled with an 

 ardent spirit of inquiry, he cannot but be impa- 

 tient under the feeling that, while Nature has 

 placed before his eyes this splendid spectacle of 

 animation, she has thrown a dense veil over the 

 interior machinery of life, and has concealed 

 from his view the springs by which she sets 

 it in motion. With the hope of discovering her 



f The red snow, discovered in Baffin's Bay on the 17th of 

 August, 1818, during the Northern Expedition, under the com- 

 mand of Captain Ross, was found to owe its colour to minute 

 fungi, or microscopic mushrooms, which vegetate on the surface 

 of snow, as their natural abode. See Phil. Trans, for 1820, 

 p. 165. 



