have been written upon it in all languages, may satisfy us, that among the wisest and most learned nations, it has never been regarded as a matter very easily understood. And from all those volumes we shall in vain attempt to collect that knowledge of its various and complicated operations, which is commonly possessed even by the common farmer; how contemptuously soever the very contemptible authors of some of them may sometimes affect to speak of him. There is scarce any common mechanic trade, on the contrary, of which all the operations may not be as completely and distinctly explained in a pamphlet of a very few pages, as it is possible for words illustrated by figures to explain them. In the history of the arts, now publishing by the French academy of sciences, several of them are actually explained in this manner. The direction of operations, besides, which must be varied with every change of the weather, as well as with many other accidents, requires much more judgment and discretion, than that of those which are always the same or very nearly the same.
Not only the art of the farmer, the general direction of the operations of husbandry, but many inferior branches of country labour, require much more skill and experience than the greater part of mechanic trades. The man who works upon brass and iron, works with instruments and upon materials of which the temper is always the same, or very nearly