As all ferments are liable to be tainted, great care ought to be taken in the choice of them, every imperfection in the ferment being readily communicated to the must. It would not, therefore, be an improper question to be determined by physicians, whether, in a time of sickness, the use of those which have been made in infected places ought to be permitted, and whether, at all times, a drink fermented in a pure and wholesome air is not preferable to that which is made among fogs, smoke, and nauseous stenches.[7] Wines from corn are distinguished by two appellations, viz., those of ale and beer. As each of these liquors have suffered in character, either from prejudice or want of a sufficient enquiry, it may be proper to levy the objections made against their use, before we enquire into the means of forming them. The most certain sign of the wholesomeness of wines is transparency and lightness; yet some, which are rich, more especially ales, though perfectly fine, have been said to be viscid.—Transparency appears indeed in many wines, before the oils are attenuated to their highest perfection, and some viscidity may therefore be consistent with some degree of brightness. Where the power of the oils and the salts are equal, which is denoted by the transparency of the liquor, viscidity can only arise from the want of age: this cannot be said to be a defect in, but only misapplication of the liquor, by being used too soon. That beers retain igneous or fiery particles, seems equally a mistake. Malt dried to keep, has undoubtedly its particles removed by fire, so far as the cohesion of them is thereby destroyed, otherwise it would not be in a fit state to preserve itself sound, or readily to be extracted. For this reason, when the grain comes in contact with the water, which is to resolve it, an effervescent heat is generated, which adds to the extracting power, and should be looked on by the brewer as an auxiliary help; but it is impossible that the malt, or the must, should ever inclose and confine the whole or part of fire employed to form them. Fire is of so subtile a nature, that its particles, when contained in a body, continually tend to fly off, and mix with the surrounding air; so that only an equal degree, with what is in the atmosphere, can be continued in the grain, or any liquor whatever, after it has been, for some time, exposed thereto.—Brown beers, made from malt more dried than any other, from experience, are found to be less heating than liquors brewed from pale malt; which probably arises from hence, that brown beers contain a less quantity of elastic air than pale beers, as pale malt liquors contain less than wines, produced from vegetables in their natural state: and as malt liquors contain their elastic air in bubbles of a weaker consistence than those made from the juices of the grape, the effect of beer, when taken in an over-abundant quantity, is neither of so long a continuance, nor