224 THE NATURAL HISTORY 



return in the same exact number annually is not easy to 

 say, for reasons given above : but it is apparent, as I 

 have remarked before in my Monographies, that the 

 numbers returning bear no manner of proportion to the 

 numbers retiring. 



LETTER XL 



Selborne, June 2, 1778. 

 Dear Sir, 



The standing objection to botany has always been, that 

 it is a pursuit that amuses the fancy and exercises the 

 memory, -without improving the mind or advancing any 

 real knowledge : and where the science is carried no 

 farther than a mere systematic classification, the charge is 

 but too true. But the botantist that is desirous of wiping 

 off this aspersion should be by no means content with a 

 list of names ; he should study plants philosophically, 

 should investigate the laws of vegetation, should examine 

 the powers and virtues of efficacious herbs, should promote 

 their cultivation ; and graft the gardener, the planter, and 

 the husbandman, on the phytologist. Not that system is 

 by any means to be thrown aside ; without system the 

 field of nature would be a pathless wilderness : but 

 system should be subservient to, not the main object of, 

 pursuit. 



Vegetation is highly worthy of our attention ; and in 

 itself is of the utmost consequence to mankind, and pro- 

 ductive of many of the greatest comforts and elegancies 

 of life. To plants we owe timber, bread, beer, honey, 

 v/ine, oil, linen, cotton, etc. what not only strengthens our 

 hearts, and exhilarates our spirits, but what secures from 



