After mashing, the malt and water are suffered to stand together unmoved, generally for a space of time equal to that they were mashed in. Was the extract drawn from the grain as soon as the mashing is over, many of the particles of the malt would be brought away undissolved, and the liquor be turbid, though not rich. But, by leaving it some time in contact with the grain, without any external motion, many advantages are gained. The different parts of the extract acquire an uniform heat, the heaviest and most terrestrial subside, the pores being opened, by heat, imbibe more readily the water, and give way to the attenuation and dissolution of the oils. When the tap comes to be set, or the extract to be drawn from the grist, as the bottom of the mash is become more compact, the liquor is a longer time in its passage through it, is in a manner strained, and consequently extracts more strength from the malt, and becomes more homogeneous and transparent. Such are the reasons why the grist should not only be mashed pretty long, but likewise be suffered to rest an equal time. It is the practice of most brewers, and experience shews it is best, to rake the first mash half an hour, to mash it one hour more, and to suffer it to stand one hour and a half. The next extract is commonly mashed three quarters of an hour, and stands the same space of time; the third, and all that follow, are allowed one half hour each, both for mashing and standing. The heat of the grist being in this manner equally spread, and the infusion, having received all the strength from the malt, which such a heat could give it, after every mashing and standing, is let out of the tun. This, undoubtedly, is the fittest time to observe whether our expectations have been answered. The thermometer is the only instrument proper for this purpose, and ought to be placed, or held, where the tap is set, adjoining to the mouth of the underback cock. The observation is best made, when the extract has run nearly half; and as, by it, we are to judge with what success the process is carried on, it is necessary to examine every incident, which may cause a deviation from the calculated heat. SECTION XIII. _Of the Incidents, which cause the Heat of the Extract to vary from the Calculation, the allowances they require, and the means to obviate their effects._ By incidents, I understand such causes as effect either the malt, the water, or the mash, during the time the brewing is carrying on, so as to occasion their heat to differ from what is determined by calculation. As these might frequently be a reason of disappointment, an inquiry into their number and effects will not only furnish means to prevent and rectify the errors they occasion, but also serve to confirm this practice.