and happineſs among the whole. We find it eaſier to make an hundred buſhels of wheat than a thouſand weight of tobacco, and they are worth more when made. The weavil indeed is a formidable obſtacle to the cultivation of this grain with us. But principles are already known which muſt lead to a remedy. Thus a certain degree of heat, to wit, that of common air in ſummer, is neceſſary to hatch the egg. If ſubterranean granaries, or others, therefore, can be contrived below that temperature, the evil will be cured by cold. A degree of heat beyond that which hatchis the egg we know will kill it. But in aiming at this we eaſily run into that which produces putrefaction. To produce putrefaction, however, three agents are requiſite, heat, moiſture, and the external air. If the abſence of any one of theſe be ſecured, the other two may ſafely be admitted. Heat is the one we want. Moiſture then, or external air, muſt be excluded. The former has been done by expoſing the grain in kilns to the action of fire, which produces heat, and extracts moiſture at the ſame time: the latter, by putting the grain into hogſheads covering it with a coat of lime, and heading it up. In this ſituation its bulk produced a heat ſufficient to kill the egg; the moiſture is ſuffered to remain indeed, but the external air is excluded. A nicer operation yet has been attempted; that is, to produce an intermediate temperature of heat between that which kills the egg, and that which produces putrefaction. The threſhing the grain as ſoon as it is cut, and laying it in its chaff in large heaps, has been found very near to hit this temperature, though not perfectly, nor always. The heap generates heat ſufficient to kill moſt of the eggs, whilſt
