which hatches the egg we know will kill it. But in aiming at this we eafily run into that which produces putrefadion. To produce putrefadion, however, three agents are requifite, heat, moifture, and the external air. If the abfence of any one of thefe be fecured, the other two may fafely be admitted.
Heat is the one we want. Moifture then, or external air, muft be excluded. The former has been done by expofing the grain in kilns to the aftion of fire, which produces heat, and extracts moifture at the fame time: the latter, by putting the grain into hogfheads covering it with a coat of lime, and heading it up. In this fituation- its bulk produced a heat fufficient to kill the egg; the moifture is fufFered to remain indeed, but the external air is ex- cluded. A nicer operation yet has been attempted; that is, to produce an inter- mediate temperature of heat between that which kills the egg, and that which pro- [ 332 i duces putrefadlion. The threfhing the grain as foon as it is cut, and laying it in its chaff in large heaps, has been found very nearly to hit this temperature, though not perfectly, nor always. The heap generates heat fufRcient to kill moft of the eggs, whilfl: the chaff commonly reftrains it from rifing into putrefaftion^ But all thefe methods abridge too much the quan- tity which the farmer can manage, and enable other countries to underfell him which are not infefted with this infeft.
There is flill a defideratum then to give with us decifive triumph to this branch of agriculture over that of tobacco.—The culture of wheat, by enlarging our paflure, will render the Arabian horfe an article of very confiderable profit. Experience has fhewn that ours is the particular cUmate of America where he may be raifed with- out degeneracy. Southwardly the heat of the fun occafions a deficiency of pafture, and northwardly the winters are too cold for the Ihort and fine hair, the particular fenfibility and conftitution of that race.
Animals tranfplanted into unfriendly cli- mates, either change their nature and acquire new fences againfl the new diffi- culties in which they