that by means of trade each distinct part is supplied with the growth of every latitude. But, without the knowledge of plants and their culture, we must have been content with our hips and haws, without enjoying the delicate fruits of India and the salutiferous drugs of Peru.
Instead of examining the minute distinctions of every various species of each obscure genus, the botanist should endeavour to make himself acquainted with those that are useful. You shall see a man readily ascertain every herb of the field, yet hardly know wheat from barley, or at least one sort of wheat or barley from another.
But of all sorts of vegetation the grasses seem to be most
neglected; neither the farmer nor the grazier seem to distinguish
the annual from the perennial, the hardy from the tender, nor the
succulent and nutritive from the dry and juiceless.
The study of grasses would be of great consequence to a northerly, and grazing kingdom. The botanist that could improve the sward of the district where he lived would be an useful member of society: to raise a thick turf on a naked soil would be worth volumes of systematic knowledge; and he would be the best commonwealth's man that could occasion the growth of "two blades of grass where one alone was seen before."
I am, etc.
NOTE TO LETTER XL.
1 Man seems to have a natural craving for flesh meat, and in some parts of Africa where vegetable food is in plenty and even luxuriance, but animal food is not so easily obtained, the desire to eat flesh causes cannibalism. It is not hunger, because hunger could be satisfied by vegetable food, but an irresistible craving for meat. The same cause may first have given rise to the odious custom in some of the South Sea Islands.
