This time it's Old Ale that's being described:
Art. II.—For Old Ale, or such as is to be long kept.
§ 1.—Heat of the Liquor.
As purity is not immediately required in this sort of ale, the first mashing heat should be as low as practicable; that is, so as just to avoid acidity in the wort, which is apt to be produced by a very low heat of the liquor. Hence 160º or 165º may be the first heat, and from 10º to 15º may be added for the second, if there be but two mashes, and 10º each if there be three. Thus if the first heat be 160º, and you find no tendency to acidity in the last running of the worts, then these rules may be observed; but if there should be a little acidity discernible, it were advisable to make the increase 4° or 5° more for the subsequent mashes, and on brewing another gyle of the same sort, from the same malt, it were best to begin at 165°, and then observe these rules for the next mashings.
§ 2.—Time of Infusion.
If the heat of the liquor be very low, the time of infusion should be somewhat less than that allowed for mild ale. Therefore, two, or two and a half hours may be allowed for the first mash, and one hour for each of the rest.
§ 3.—Quantity of Hops, and time of boiling.
The general rule for hops is one pound per bushel of malt; but if it be intended that the ale should retain its mildness to a very distant period (which by the bye is to answer a very useless purpose), a larger portion of hops must be used, agreeably to the intention of the brewer.
The boiling is regulated by time, as the nicety of flavour is not such a requisite in this as in mild ale. In two worts the boiling may be from an hour to an hour and a half for the first, and two or two and a half hours for the second; in three worts, the first may boil one hour, the second an hour and a half, and the last two or two and a half hours.
§ 4.—Quantity of Yeast, and mode of Fermentation.
If the first heat of fermentation be not below 60º, and the gravity not much more than thirty pounds, provided the air be temperate, the quantity of yeast must be from two to two and a half pounds per barrel, applied in the manner as directed for mild ale. If the heat be lower, the specific gravity more, or the heat of the atmosphere less, the quantity of yeast must be increased in proportion; in doing of which, no great inconvenience can arise from applying a few pounds too much, but it may occasion an imperfect fermentation if there be a few pounds too little.
The heat of the fermentation should not exceed 75º at the highest, but rest between that and 70º, though the nearer 75° the better will be the flavour of the ale at an early period; and as a low heat of mashing is conducive to a great increase in the heat of fermentation, it will thence be evident that the fermentation for ale, whose average gravity is thirty pounds, must begin at or below 60 , and the precautions before recommended respecting the yeast, must be particularly attended to. The mode of conducting the fermentation, and the criterion for cleansing, being the same with those directed for mild ale, a repetition here would be superfluous.
I, however, recommend a more strict adherence to the rules for cleansing, before inculcated in this process, than in that for mild ale, because the first heat being lower, a greater time is necessary to bring the fermentation to perfection, and secure the future good flavour of the ale. It may be here observed that this sort will generally require finings."
"The art of brewing" by David Booth, 1829, pages 43 - 44. (Copy of text from Richardson's "Philosophical Principles of the Science of Brewing." 1798.)
One important point before we continue. It's about Ale, Mild and Old. Old Ale was not simply Mild Ale that had been aged. Old Ale was brewed to be aged, While it might well have used the same basic recipe as a Mild Ale, it would have been tweaked - principally in the quantity of hops used - to help it keeping qualities. Just thought I'd make that crystal clear.
Here there's a difference in the process for the Old Ale. Specifically, it's mashed cooler. I can't think of an reason for doing that myself, but I'm sure there must be one. The mashing scheme, with two or three separate mashes, is very 18th century. Though, in England, brewers continued to mash several times well into the 19th century. And yes, I do have an example. Two, in fact. a XXX and a XXXK from Truman from 1831. XXX being a Mild Ale and XXXK a Stock, or Old Ale. Let's take a look:
Doesn't look to me as if the Keeping version was mashed any differently. And neither is anything like as cool as Richardson's recommendation.
A pound of hops per bushel is 8lbs per quarter. How does that compare with some real beers? In 1837, Whitbread's KXXX was hopped at 7.64 lbs per barrel, KXXXX at 8.06 lbs. About exactly the same. The Truman XXX from above was hopped at 8 lbs per quarter, the XXXK at 14 lbs per quarter. Rather more than Richardson suggests.
The fermentation temperatures look about right: pitching at around 60º F and letting the temperature rise no higher than about 75º F. That's very similar to how Whitbread fermented their Ales in the 1830's. Their Porters, on the other hand, they fermented warmer: pitched at 63-64º F, rising to about 80º F.
30 pounds gravity is 1083º. Which, in the 1830's, would have been an XX Ale, on the scale of 1 to 4 X's. Not particularly strong.
I was surprised that finings were needed. I thought one of the points of ageing beer was to allow it to drop bright spontaneously.