Note 40 — PART II. THE PRACTICE OF BREWING. (continued 3)

The yeast or air bubbles produced from natural wines, vary not only in their consistence, but also in their volume; so that, in their act of fermentation, a progressive effect is the consequence of this want of uniformity. The yeast or air bubbles of barley wines are more uniform; to imitate nature, it is necessary to apply this principle of fermentation by degrees, to cause a progressive effect only. Feeding of drink is the only means to gain this end; thereby the newly applied yeast maintains the drink in its required agitation, in a similar manner as the increased heat and action raised by fermentation causes the air bubbles in natural wines to act and explode, in proportion to their consistence, and to the quantity of elastic air the bubbles contain; and so requisite it is periodically to apply more yeast to this sort of liquor, or regularly to feed it with this enlivening principle, that, in very hot weather, when this, through carelessness, has been omitted, I have known this ale to become foxed or putrefied, and could attribute this accident to no other cause but to a neglect of this sort, as the worts had been regularly brewed, laid thin in the coolers, received all the cold the night could give them, and the tun in which the drink was worked was perfectly clean.