INTRODUCTION. 3 



As some portions of the earth, in the produc- 

 tion of animals and vegetables, conduce more to 

 the supplying the wants of mankind than others, 

 so are some species of animals and vegetables 

 more productive and eligible than others, and 

 not only one species more so than another, but 

 some varieties of the same species are more valu- 

 able than others ; therefore it must be obvious, 

 that as well as enquiring into the- general nature 

 and various qualities of the earth, we must also 

 enquire into and ascertain, the qualities of those 

 varieties of animals and vegetables which are the 

 most conducive to our wants, and what causes 

 produce those varieties, or diminish or increase 

 their peculiar qualities. But as the qualities which 

 give value to the different varieties of animals and 

 vegetables must depend on peculiar circumstances, 

 it can be of little use in a work like this, to attempt 

 a particular description of these : and although 

 it is obvious, that the physiology of both animals 

 and vegetables form the fundamental principles 

 of the science of husbandry, it does not follow 

 that it must also comprehend a knowledge of the 

 comparative anatomy of either animals or vege- 

 tables ; this is of trifling consequence to the hus- 

 bandman. I shall therefore interfere very little 

 with the departments of zoology or botany. 



