179 



These are but specimens of the products which flourish only in their 

 appropriate latitudes ; some requiring perpetual summer, which they 

 could not enjoy were the earth's inclination very much greater ; and 

 others requiring the precise alternations of season which they could not 

 have, were the inclination very much less. The winter grains require 

 the frosts of Avinter, as well as the peculiar temperature of a northeru 

 summer, to perfect their qualities. The northern potatoe, to which mil- 

 lions of our race owe their very existence, and many other varieties of 

 roots, will scarcely grow at all in soil which never freezes, or which rises 

 to any thing approaching a tropical temperature ; while the sweet potatoe 

 steps in where the other steps out, an inferior quality of each lapping a 

 little upon the domain of the other ; but neither will succeed at all where 

 the other grows in perfection. And, bulky as these products are, iu 

 proportion to their value, they are becoming articles of extensive inter- 

 change between neighboring States, while the inhabitants of each, fancy 

 (nor is it a mere fancy) that they have added a new luxury to their 

 tables, by the exchange. 



In addition to latitudinal varieties of climate and season, we have 

 longitudinal subdivisions and modifications of the same, varying with the 

 extent of country, its relative position to the ocean and its elevation 

 above its level, and bringing in a greater variety of products than could 

 consist with mere latitudinal divisions. For example, in the same lati- 

 tude, the climate and seasons are quite different in Europe and America. 

 Hence, there are many products of American soil, which, for want of 

 sufficient heat in summer, will not mature at all in the same latitude in 

 Europe ; and many products of the same latitude in Europe, on account 

 of the severity of our winters, are impracticable upon American soil. 



I would not, however, be understood as maintaining that, in any parti- 

 cular country, those plants alone should be cultivated, which are indige- 

 nous to that country. Many varieties, both of plants and animals, may 

 be transposed without injury, and an occasional change of locality will 

 often improve grains, provided too great a deviation from their native 

 latitude be not allowed. The potatoe, is a native of America, yet its 

 migration across the ocean, is supposed to have doubled the population 

 of Great Britain and some other portions of Europe ; and the introduc- 

 tion of European grains and grasses and domestic animals, upon Ameri- 

 can soil, has wrought still greater changes in the New World. But this 

 does not militate against the special adaptation of a great variety of 



