FINAL CAUSES. 27 



startled at the prospect of fields of a scarlet hue, the result 

 of a wide expanse of microscopic vegetation.* 



But whatever charms the naturalist may find in the oc- 

 cupations 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 inferior in- 

 tellects are content to rest, serves but to awaken, in him 

 who has learned to think, a desire of farther knowledge. 

 Filled with an ardent spirit of inquiry, he cannot but be im- 

 patient under the feeling that, while Nature has placed be- 

 fore 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 proceed- 

 ings, he hastens to explore the several parts which compose 

 the organized fabric, to examine in minute detail the anato- 

 my of its structure, and to ascertain the nature of the seve- 

 ral actions that take place within it. But overwhelmed by 

 the multiplicity of objects, and lost amidst the compli- 

 cation of phenomena, he soon becomes dismayed by the 

 magnitude and arduous nature of the investigation. He 

 finds that his labours w^ill be of no avail, unless, previous- 

 ly to any attempt at theory, he takes a careful and accu- 

 rate account of all the circumstances attending the history 

 and conditions of life, from the dawn of its existence to its 

 appointed close. On tracing living beings to their origin, he 

 learns that every individual vegetable and animal takes its 

 rise from an atom of imperceptible minuteness, and gradual- 

 ly increases in bulk by successive accretions of new matter, 

 derived from foreign sources, and by some refined, but un- 

 known process, transmuted into its own substance. Then, 



* The red snow, discovered in Baffin's Bay on the 17th of August, 1818, 

 during- the Northern Expedition, under the command of Captain Ross, was 

 found to owe its colour to minute fung-i, or microscopic mushrooms, which 

 veg-etate on the surface of snow, as their natural abode. See Phil. Trans, for 

 1820, p. 165. 



