Recreating Medieval English Ales

(a recreation of late 13th - 14th c. unhopped English ales)

(designed and brewed by Tofi Kerthjalfadsson, Sept. 23rd -- Dec. 28th, 1998)

In medieval England, ale was an alcoholic drink made from grain, water, and fermented with yeast. The difference between medieval ale and beer was that beer also used hops as an ingredient. Virtually everyone drank ale. It provided significant nutrition as well as hydration (and inebriation). The aristocracy could afford to drink wine some of the time as well, and some times the poor could not even afford ale, but in general ale was the drink of choice in England throughout the medieval period.

These recipes are a modest attempt to recreate ales that are not only "period", i.e. pre-17th century, but is actually medieval. These ales are based on newly available evidence from the late 13th and early 14th centuries.

Not only was beer significantly different some three hundred years ago, in 1700, in comparison to today, ale was significantly different around 1300 than either ale or beer was in 1600. The primary reason for this difference in the product is a seemingly small difference in technique: for an ale, the wort, the liquid containing sugars and protein extracted from the grain, was not boiled prior to fermenting. For a beer, the wort had to be boiled with the hops. This seemingly small difference was in fact a change in technology that had long-reaching consequences for the preservation, as well as taste and nutritional value of the beer.

To make these ales I've tried to use only medieval techniques and appropriate equipment. I have not used the most egregiously modern tool, the thermometer. The first batch I did not even measured my results with a hydrometer (a tool used by modern brewers to measure the quantity of sugars dissolved in a liquid). The efficiency of a batch - the extent to which starches in the grains have been turned into sugars disolved in the liquid - can be measured with this tool. Also by comparing the hydrometer measurement from prior to fermentation with the post-fermentation measurement, the alcohol content of a brew can be deduced. Although I did measure the results of the second batch with a hydrometer, I did not adjust or an any other way alter this batch on the basis of these measurements.

First I will present the main sources for these recipes, then my actual recipes for these ales, and finally a discussion of the recipes. This discussion starts with a brief summary of ale and ale brewing in medieval England, and then discusses my choices of ingredients, the quantities and proportions involved, and finally the methods used to make the ales. This discussion section is critical to the appreciation of the recipe, since some of the methods differ substantially from modern, or even 16th--17th C. beer brewing methods.

Main Sources

These two recipes are based on two pieces of information from Bennett's book:

Our most direct evidence of domestic brewing comes from elite households. In 1333--34, the household of Elizabeth de Burgh, Lady of Clare, brewed about 8 quarters of barley and dredge each week, each quarter yielding about 60 gallons of ale. Brewing varied by the season of the year, with vast amounts produced in December (when more than 3,500 gallons were brewed) and quite restricted production in February (only 810 gallons). The members of the Clare household drank strong ale throughout the year, imbibing with particular gusto during the celebrations of Christmas and the New Year.

[Bennett, p. 18]

... In 1282, when Robert Sibille the younger was presented at the court of Kibworth Harcourt for selling his ale at too high a price, the stipulated price left him little room for profit. Having paid 2s. for 4 bushels of malt and required to sell 5 gallons of ale for 2d., he would have had to draw 60 gallons from his malt just to recoup his investment. His ale, in other words, would have been very weak indeed and his profits very low.

[Bennett, p. 21]

These two recipes are based on these quotes (and other information). The first, Weak Ale, recipe is based on the Clare household grain mix, but at the cost-break-even strength of Robert Sibille the younger.

The second recipe is a recreation of the Clare household ale, at full strength, and correcting several minor details in the ingredients.

Many of the details of these recipes are different than a modern all-grain brewer might expect; I have endeavored to explain the evidence and reasoning behind all of the choices in ingredients and techniques in the discussion section below.

Recipe 1: Weak Ale

For 2 1/2 gallons of ale:

Ingredients:

4 2/3 lbs., Hugh Baird brand English Pale malt

1 1/2 lbs., oats (rolled)

13 qts., water

1 pkt, Danstar brand Nottingham ale yeast

1 pkt, Danstar brand Windsor ale yeast

results as of batch 4 (Dec. 3 1998) indicate that this is the best yeast mix after all.

results as of batch 4 (Dec. 3 1998) indicate that this is the best yeast mix after all. 1/4 oz., Light Oak chips

I would leave this out for future batches - see below about Oak

Sanitize an insulated tun (I used my 10-gal. Gott mash-lauter tun), and a fermentation vessel (a 4-gal. food-grade plastic bucket with lid). Also sanitize a strainer if needed to separate liquid from grain.

Boil water. Crush the malt, then mix it well, while still dry, with the oats.

Open up the insulated tun and place it on the floor near the stove (where the boiling water is). Pour 2 quarts of water into the tun from a reasonable height, moderately slowly. (The idea here is to let the water release some heat in water vapor while pouring -- see the techniques section below under mashing.)

Pour all the dry grain into the lauter tun.

Slowly pour 3 more quarts of boiling water over the grain. Don't stir. Put the cover on the tun and let it stand for 10 mins. Then add 1 more quart of boiling water. At this point, there should be a very small amount of visible liquid. Put the lid back on and wait 20 more mins.

Now take the lid off and stir it all up. It should be about the consistency of fairly thick porridge. Put the lid back on and do something else for a while -- at least an hour and a half. (I went out for a beer with some friends for 3 1/2 hours.)

Open up the tun and stir in 3 more quarts of boiling water, and stir. Close up again and wait 25 more mins.

Finally, add remaining boiling water (4 quarts -- don't worry about pouring it in from a height). Stir well.

Set up the sanitized fermenter. Open the mash tun valve (or otherwise start straining out the wort, that is the liquid part, from the grain. (Unlike modern methods, I did not recirculate the liquid in any way.) The first gallon should go quickly; straining the last gallon should be done somewhat more slowly in order to get most of the liquid out.

Close the fermenter and let the wort cool overnight.

Rehydrate both packages of yeast according to the package instructions (being careful to use water that has been boiled and cooled, and a glass that has been sanitized in some way). Pitch the yeast into the wort, and shake, stir, and otherwise agitate the wort in order to aerate it.

Let the ale ferment for a day; the yeast should have started, and activity should be well under way. Boil the oak chips in approx. 1 cup water. When the water is the color of a cup of tea, take off heat and allow to cool some. Pour off water, then add approx. 1/2 cup of water back into chips. Raise this to a boil again, then allow to cool; it should be just barely darker in color than normal water. Add this oak-water to the wort.

Let the ale ferment for a couple more days. Draw off and serve.

Observations on the product, Sep. 26, 1998

The ale was first served when still young (i.e. not done fermenting). Surprisingly, and counter to the conjectures of some historians, this ale was not sweet. Much of this lack of sweetness could be explained by the ale being (deliberately) weak.

It tasted somewhat like "liquid bread" -- much more so than more modern beer. It also had a fair amount of tannic taste; much more than could be explain by the addition of oak. I suspect this was mostly due to the final addition of boiling water just before straining out the liquor. This would tend to have the effect of extracting tannins from the hulls of the barley.

It was presented on a fairly hot day; several people commented on how refreshing such a drink could be in such conditions. It also seemed to have a fairly low alcohol content, though since I did not do a specific gravity measurement on it, I could not say what the true strength of the ale was.

Recipe 2: Clare household Strong Ale and Ordinary Ale

(batches 2 -- 5)

Two ales, one strong and one ordinary, of between 1 1/2 and 2 gallons each, can be made thus:

Ingredients:

8 lbs., Hugh Baird brand English Pale malt

1 1/3 lbs., (Baird) Pale malt, roasted.

For darker ale, roast to amber: 30 mins. at 225 F. followed by 30 mins. at 300 F. For lighter, roast an hour at 225 F.

For darker ale, roast to amber: 30 mins. at 225 F. followed by 30 mins. at 300 F. For lighter, roast an hour at 225 F. around 3 lbs., oats (rolled)

14 to 16 qts., water (main batch)

14 will produce 1 1/2 gallons of ale; 16 will produce 2 gallons

14 will produce 1 1/2 gallons of ale; 16 will produce 2 gallons 6 to 8 qts., water (second runnings)

1 pkt, Danstar brand Nottingham ale yeast

1 pkt, Danstar brand Windsor ale yeast

Pre-heat the oven to 225 degrees F. Measure out 1 1/3 lbs. of pale malt, and place it in an e.g. 9 x 13 inch baking pan. When the oven is hot, place the malt in the oven and bake for 30 mins. Then increase the heat and bake another 30 mins. Or, for a lighter colored ale, simply bake 60 mins. at 225 F. Remove and set out to cool.

Sanitize an insulated tun (again, my 10-gal. Gott mash-lauter tun), and two fermentation vessels (two 3-gal. food-grade plastic buckets with lids).

Boil water for first runnings (14 to 16 qts.). Crush the malt, mixing the amber (baked) malt with the pale malt. Then mix the oats with the crushed malt well.

If your tun has a false bottom or other similar device, pour in enough boiling water to cover it. Then pour in all of the grain. Finally, slowly ladle the remaining water over the grain, pouring from some height.

Cover the mash tun and let sit 30 mins. Open and stir well, then close and let sit another 3 1/2 to 4 hours. This is a hot mash, so it will need this long period of time to mash (convert the starches into sugars).

Put the water for the second running on to boil. Set up the first fermentation vessel under the drain valve or tube of the insulated tun, and slowly run the liquor from the first mash into the first vessel. Close and set aside to cool.

After the first liquor has been drained out, and when the water for the second running has reached a boil, pour it into the damp grain. Allow to sit for 30 mins, then set up the second fermentation vessel and run this liquor into it. Close the second fermenter, and allow both to cool overnight.

In the morning, sanitize a smaller pan or ladle, a Pyrex measuring cup, and a spoon. Also boil about a cup of water and cool it, covered. Rehydrate the packets of yeast into 3/4 cup of the boiled water. Pour this yeast mixture into the two fermenters, 2/3 into the strong main batch, 1/3 into the second runnings. Use the sanitized ladle to aerate each of the batches (by picking up liquor and pouring it back in turbulently).

Close the fermenters (filling the water locks, if any) and allow to ferment.

About the recipe

Unlike the first batch, this second batch was based on the proportions used in an aristocratic household. There was probably less concern for the materials cost of the resulting ale, since it would be consumed by the members of the household, rather than being sold at a profit. So, as in other things, the aristocracy had more, and thus could afford to emphasize quality to a greater extent.

This is reflected in the recipe. It used twice as much grain as the first, Weak Ale recipe for less quantity of ale. Unlike the first batch, I measured the specific gravity of both runnings of this batch in order to gauge how well this set of techniques work. The first runnings of batch 2 had an impressive starting gravity of 1.091, about the same starting gravity one would expect in a wine. The first runnings of batch 3 were 1.085, and batch 4 were 1.090. The second runnings of batch 2 had a starting gravity of 1.051, about the same as a reasonably strong modern beer. (I did not collect second runnings from batches 3 or 4.)

This technique is not very efficient. In modern brewing, using a thermometer to carefully control the mash and carefully sparging (rinsing out) the grain, I usually expect to get at least 25 points (thousandths) of specific gravity for every pound of grain per gallon of liquid. (So if I made 5 gallons of beer with 10 lbs of malt, I would expect to get a starting specific gravity of over 1.050: 1.000 for the water, plus 0.025 * 10 lbs / 5 gallons.)

For the first runnings of batch 2, I got an efficiency of 11 points per (lbs/gal). The second runnings gave an additional 6.2 points per (lbs/gal). This improves the total up to 17.2 -- still much worse than the 25+ I can get with modern techniques. The first Batch 3 worked out to about the same, and batch 4 worked out to 2 gallons at 1.090, or 15 points per (lbs/gal).

To the modern brewer, the quantities of grain described in these sources seem extraordinarily large. However, the process seems to be so inefficient that large quantities of grain are required to produce ale of adequate strength using these older techniques.

Observations on the second batch, Oct. 31, 1998

1 pkt, Danstar brand Nottingham ale yeast

1 pkt, Danstar brand Windsor ale yeast

1 pkt, Fleischmann's brand bread yeast (plain, not quick-rise)

Dregs from 1 bottle, Cantillon brand Gueuze Lambic

Something in the revised yeast mixture was a mistake. The ale fermented out quite quickly, with much less activity on the morning of day 4 than there was the previous evening. So it fermented.

There was, however, a nasty and strong under- and after-taste, that was reminiscent of a minor taste in Lambic. My current suspicions are that adding the bread yeast to the ale yeasts was not a problem, but that adding dregs from the Gueuze was the cause of this bad taste. Other brewers have suggested that this batch should be allowed to age for a year and tasted after that. I will be doing this, but such age is strictly counter to the evidence (below) that ale was served fresh.

Observations on the third batch, Nov. 21, 1998

1 pkt, Danstar brand Nottingham ale yeast

1 pkt, Danstar brand Windsor ale yeast

1 pkt, Fleischmann's brand bread yeast (plain, not quick-rise)

This batch did not have some of the more subtle nasty under-tones of the second batch (with the Lambic), but still had a really nasty smell and taste reminiscent of paint thinner.

Observations on the fourth batch, Dec. 3, 1998

The nasty paint-thinner taste is gone, and the bread yeast seems to be the culprit. In retrospect this isn't too surprising - bread yeast has been raised to produce a maximum amount of CO2 gas, and any higher-order alcohols that the yeast may produce will be burnt off when the bread is baked. In ale, however, these off flavors will stay in the batch, harming the taste. So, in the end, this bread yeast proved unsuitable for brewing (which is not exactly a big surprise).

The fourth batch is strongly alcoholic, but has a pleasant, apple-like taste. All in all, it tastes like a stronger and more pleasant version of the weak ale (above).

The yeast mixture probably can be improved upon, but I have not yet found a quick-and-dirty method of substantially improving the mixture over using these two ale yeasts.

Discussion

Important Texts

As stated above, these recipes are primarily modeled on evidence in Judith Bennett's recent book.

Also important in the crafting of this ale were several Elizabethan-era references. William Harrison, in 1577, provided a detailed description of how his wife brews beer [Misc-4]. Gervase Markham, in 1615, published The English Housewife, which contains not only an entire chapter devoted to brewing and the keeping of wine, but also an entire chapter on how to malt grain [Markham]. Kenelme Digbie, in 1669, wrote The Closet ... Opened..., a book of recipes, many of which are for various alcoholic beverages [Digbie].

Other useful modern texts include Cindy Renfrow's A Sip Through Time, a collection of recipes and other useful information [Renfrow]. Also worth reading is Beer, A History of Suds... by Gregg Smith. Though most of this book is devoted to the history of Beer in America, the first few chapters have some valuable information for the medievalist.

About Medieval English Ale

In England in the middle ages, particularly before the Plague (which first reached England in 1348), the most common drink of the day was ale. Ale, during this time, was a drink made from malted grains, water, and fermented with yeast. Malted grain would be crushed; boiling (or at least very hot) water would be added and the mixture allowed to work; finally the liquid was drained off, cooled and fermented. The ale might have been spiced, but it would not have had hops as an ingredient.

Beer, on the other hand, was made from malted grains, water, hops, and fermented with yeast. Hops added a measure of bitterness to the beer, and also helped preserve it. We will see below that the successful addition of hops required a change in the process that had a profound effect on the resulting product: after the liquid was drained off, it was boiled again with the hops.

Bennett has found a record of a Richard Somer who was selling Flemish ale (i.e. beer) in Norwich in the late 13th century. This was, however, a special case; the next record of the selling of beer that Bennett found was not until some hundred years later, with merchants along the eastern and southern coasts of England starting to import and sell beer in the 1370s [Bennett, p. 79]. It should be emphasized, however, that this was still somewhat of a special case -- beer was not a wide-spread drink until the late 16th century [Bennett, p. 81; Smith, pp. 25--26]. And even then, ale was a widely popular drink. Again quoting Bennett:

... As John Grove put it in 1630: WINE: I, generous wine, am for the Court

BEER: The City calls for Beer

ALE: But ale, bonny ale, like a lord of the soil in the Country shall domineer.

[Bennett, p. 81]

Fresh Ale

In medieval England ale was served fresh, still (or very recently) fermenting, as opposed to stale, or done fermenting and cleared.

Since ale was basic to the diet of ordinary people, each household required a large and steady supply; a household of five people might require about 1 1/4 gallons a day, or about 8 3/4 gallons a week. Yet ale was both time consuming to produce and fast to sour, lasting for only a few days. 17

[Bennett, p. 19] 17. At Elmley Castle (Worcestershire) in 1446, for example, alebrewers were proscribed from selling ale more than four days old. Warren O. Ault, Open-field husbandry and the village community, Transactions of the American Philosophical Society, n.s., 55, part 7 (1965), item 147, pp. 77-78

[Bennett, p. 190 (text of endnote 17)]

From this evidence, we can conclude that any production method that allows the ale to keep for a long time is probably not what we are after. Likewise, any ingredient or production method that forces us to age the ale for a long time to become drinkable is not right either. Earlier in the medieval period, the ale-brewers were making smaller batches in their own houses, rather than brewing in industrial quantities. They simply did not have either the space or the resources to age the ale for long periods of time before selling it.

Expensive Ale

Ale was somewhat expensive to both produce and buy. In 1310, an unskilled laborer was paid at most 1 1/2 d. (pence) per day of work [Bennet p. 24]. We will see below (under "grains") that in the Oxford market in 1310, a bushel of wheat cost between 10 and 12 pence per bushel, or 6 2/3 to 8 days of unskilled work, with barley going for 7.5 d/bu, or 5 days, and oats going for 4 d/bu, or 2 2/3 days. A bushel of grain would yield between 7 1/2 and 10 gallons of ale [Bennet p. 23], which would be sold for 1 1/4 to 1 1/2 d. per gallon.

Now aside from the economics of profitable sale, discussed below, it is worth pointing out that both the grain, and consequently the ale, was expensive for the laborers. In short, a gallon of ale cost roughly a day's work. The combination of modern large-scale farming and production techniques, and increased wages, make grain in the 20th century United States roughly 1/10th as expensive as it is was in 13th C. England.

Medieval English Ale and modern Homebrewing

Another aspect of this project is that it is an all-grain brewing. Many brewers within the SCA make beer in about the same way any other modern hobbyist home-brewer does: they buy commercial malt extract, which is a concentrated or dried malt-sugar solution. This is combined with water, and the result is boiled. Hops, dried hop flowers, may be added, or the malt extract may have been hopped in the factory that produced it. This then is cooled, yeast is added, and it is fermented.

All-grain brewing is somewhat more ambitious, since the sugars must be extracted from the malt by the homebrewer. It is, however, more controllable. The flavor of the beer can be changed substantially by the choice of type, quantity, and roasts of malted barley, as well as other grains. The flavor and "body" can also be effected by the method of mashing -- process by which the starch in the grain is converted to sugars -- as well as the mash temperatures. I personally find all-grain brewing to be preferable to extract brewing -- I like the added control that mashing affords, and it is much closer to how the process is done on a commercial level today, as well as historically. It is also cheaper; the grain for an all-grain batch costs about half of what the extract would to make an equivalently sized batch. This doesn't come for free, however. All-grain brewing requires some very large and fairly expensive equipment.

For the SCA brewer, all-grain brewing has another advantage: one can use the techniques used by brewers in the few late-period recipes that we have. These techniques are somewhat different than those used today; for a full description please see my thoughts on Elizabethan Homebrewing.

For this project, however, there was no choice. One cannot buy malt extract that is anything like the wort produced by this brewing; these batches are sufficiently unlike anything that can be purchased, so it cannot be "simulated".

One interesting irony of this project is that it matches the observation by Bennett, that beer brewing requires more equipment than ale brewing [Bennett, pp. 86--87]. In creating 2 1/2 gallons of ale, the only specialized piece of equipment I used was a large cooler, which I used as a lauter tun. In retrospect, I could have easily made a 5 gallon batch of this ale with the same equipment, save for a larger fermenter. I did not need the large pot, nor the burner to put this pot on, that I use for making 5 gallon batches of beer.

Materials

Grains

Our most direct evidence of domestic brewing comes from elite households. In 1333--34, the household of Elizabeth de Burgh, Lady of Clare, brewed about 8 quarters of barley and dredge each week, each quarter yielding about 60 gallons of ale. Brewing varied by the season of the year, with vast amounts produced in December (when more than 3,500 gallons were brewed) and quite restricted production in February (only 810 gallons). The members of the Clare household drank strong ale throughout the year, imbibing with particular gusto during the celebrations of Christmas and the New Year.

[Bennett, p. 18]

So the Clare household ale was made using between 2/3 and 3/4 malted barley, with the remainder being oats.

Consider, for example, the possible profits of brewers in Oxford during the early years of the fourteenth century. In the late autumn of 1310, a jury gathered to review grain prices and to set the ale prices accordingly. Stating that wheat had recently sold in the Oxford market for 8s., 7s.4d., or 6s.8d. a quarter (depending on quality); barley for 5s.; and oats for 2s.8d., it set prices for good ale at 1 1/4 d. in cuva and 1 1/2 d. in doleo. The first price was the more standard of the two. What profits could a brewer have expected from buying grain at these prices and then selling ale made from it at 1 1/4d. the gallon? For a brewing of 3 bushels of malt, the range of possible costs (shown in the four left-hand columns of figure 2.1) and receipts (shown in the four right-hand columns) was very broad. The first two estimates of cost assume that an Oxford brewer would have brewed malt made from equal amounts of wheat, oats, and barley. ... The next two estimates of cost assume a different ratio of grains in the malt, one similar to that employed at St. Paul's: two-thirds oats and one-sixth each for barley and wheat. ...

[Bennett, pp. 22-23]

Malting is a process which both preserves a grain for longer-term storage than is possible in the raw form, and activates enzymes in the grain that help turn starches into sugars. After the grain is harvested, it is moistened and allowed to sprout and grow for a few days, then dried in an oven at low to moderate temperatures, and finally threshed and stored.

Traditionally the sprouting would be carried out on a large floor [Markham, pp. 182-185], often in the attic of the malt house. As the grain sprouts, it generates heat, which must be allowed to escape so that the malting grain does not cook itself. The young plants also require carbon dioxide to continue growing. To facilitate this, the malt is turned (scoop it up, flip it over) at regular intervals. A few British maltsters are still producing floor-malt today, though it is rare and expensive.

Historically, kilning was often carried out in what is essentially a large wood oven or smoker. The malt would be spread out on a false-floor made of hair-cloth, straw mat, or other suitable material, on top of some type of loose material, in order to allow the hot exhaust from the kiln's oven to evenly penetrate the grain. Then a wood fire would be built in the oven, and the malt baked for several hours, and occasionally turned to prevent burning [Markham, pp. 186-190].

Modern kilning is quite different. Today the malt is roasted in a drum with a water spray to control temperature, patented by D. Wheeler in 1817 [Harrison]. Because of this spray, malt can be roasted much, much darker than was possible in an oven. The water spray also allows lighter malts to be made much more consistently, and without picking up any flavor from the fuel used to fire the kiln.

Often, to better approximate amber and brown malts, I have roasted some portion of Pale malt in an oven. For the first batch of weak ale, which was an initial test of a recipe and several techniques, I did not go to the extent of roasting the malt, but used only straight Pale malt. Baird brand malt is roasted slightly more than many other English Pale malts; it is practically a Mild, rather than Pale roast. Mild is generally roasted just slightly more by the maltster.

For second batch, however, I oven-roasted a small portion of the malt. Roasting some of the malt better simulates the oven-kilned nature of medieval malts - particularly the unevenness of the malt kiln. Since this also adds a nice flavor to the resulting ale, it seemed like the right choice for the second batch.

I wanted to roast the malt some, but not too much. So I selected a portion of the malt and baked it in the oven, first for half an hour at 225 degrees F., then an additional half hour at 300 degrees F. This gave a nice amber roast to some of the grain. (It is important not to do this to to all of the malt, since the roasting procedure can destroy the enzymes that are used in the mash to convert unfermentable starches into fermentable sugars - see below in the techniques section.)

The information about the brothers at St. Paul's, brewing in 1340--41 [Bennett, p. 191; end-note text 21], says that oat malt was the predominate ingredient. Unfortunately, malted oats are currently unavailable commercially. So I was forced to compromise by using the Clare household mix of 3/4 barley, 1/4 oats, and further compromise by using unmalted oats. As a result, the flavor won't be quite right, but it will be closer than by completely ignoring this evidence and using entirely barley malt.

Yeast

Both Digbie and Markham recommend making a yeast starter in order to have a sufficient quantity of yeast to attack the large size batches they are making. Digbie advises [Digbie, pp. 99]:

... This quantity (of a hogshead) will require better then a quart of the best Ale- barm, which you must put to it thus. Put it to about three quarts of wort, and stir it, to make it work well. When the barm has risen quick scum it off and put to the rest of the wort by degrees. The remaining Liquor (that is the three quarts) will have drawn into it all the heavy dregs of the barm, and you may put it to the Ale of the second running, but not to this. Put the barm you have scummed off (which will be at least a quart) to about two gallons of the wort, and stir it to make that rise and work. Then put two Gallons more to it. Doing thus several times, till all be mingled, which will require a whole day to do. Cover it close, and let it work, till it be at it's height, and begin to fall, which may require ten or twelve hours, or more. Watch this well, least it sink too much, for then it will be dead. Then scum off the thickest part of the barm, and run your Ale into the hogshead, ...

Using a starter is good practice in modern, as well as medieval brewing. Starting with a large quantity of yeast will reduce the effects of wild yeasts and other microorganisms by overwhelming them by sheer number, and by eating up all the available sugar. This will help keep the ale from catching unwanted infections, since there will be less for undesirable microbes to feed on.

Yeast Culturing, and lack thereof

Yeast was cultured in the medieval period, but not to the extent that we would think of today. Back then many people were brewing, and yeast was freely shared amongst brewers. Since yeast that produced good ale and beer was valued and shared, good yeast was cultivated.

Now, however, not only is good yeast treasured, it is also cultured in laboratory conditions, usually starting from a single cell culture. Since yeast reproduces by budding, most cultured yeasts today are all alike to the point of being clones of each other [Ligas].

Since these were small batches, I simply rehydrated yeast from dried packets. For the first batch, in order to slightly simulate the multiple strains of yeast that would make up medieval ale barm, I used two different strains of yeast. For the fourth batch, I've gone back to this mixture, since it gives by far the best results so far.

Experiments in yeast mixing

After presenting the first batch at a local event, and posting the recipe for the first batch to the historic home-brewers' (internet) mailing list [hist-brew], I received two interesting comments regarding the yeast mixture. Marc Bloom (AKA "Red") commented that if I was interested in yeast diversity, in addition to ale yeast I might consider adding bread yeast. He also said that he remembered reading that one (modern) English brewery uses a very unusual yeast strain, available to consumers as Fleischmann's brand bread yeast [Bloom]. So I added this to the mix for the second batch.

In addition, Al Korzonas wrote:

Finally, I'm willing to bet that all beers made more than 200 years ago had a significant amount of bacterial and Brettanomyces sourness. For authenticity, I'd pitch the dregs from a bottle of unfiltered Lambic (like Cantillon, Boon Marriage Parfait or Lindeman's Cuvee Rene) for the Brettanomyces and lactobacillus that was most certainly a part of any beer made more than 200 years ago. Pitch it early in the ferment for more character, late for less. You can expect to have a rather long, lingering fermentation when you add Brettanomyces because it is pretty slow and because it will eat many carbohydrates that Saccharomyces simply won't eat. If [you] plan to bottle, a year is not too long to wait for the Brett and lactos to finish their work.

[Korzonas - letter]

Following this advice, I also added the dregs from a bottle of Cantillon Gueuze to the yeast mix for the second batch (even though these ales are meant to be drunk much earlier than a year old.

As noted above, the second batch developed a strong nasty taste that was very much like one of the minor tastes in good Lambic. So I left the Lambic dregs out of the third batch. The third batch did, however, have the Fleischmann's bread yeast as part of the mixture. This third batch quickly developed a very clean, very bad smell and taste that was reminiscent of paint thinner.

So it seems that it was not necessarily the Lambic that gave the off tastes; instead that Fleischmann's bread yeast is unsuitable for brewing ale. As I have yet to try adding the Lambic dregs to a mixture of otherwise known-good yeasts, I'm reserving judgement on this move until I try the next logical experiment.

Water

Oak

On the other hand, according to Bennett, there is evidence of brewing in vessels other than oak:

When Denise Marlere died in February 1401, she left behind a thriving brewing business in the town of Bridgewater. She bequeathed the bulk of her business to her servant Rose: half of a tenement, all of her brewing vessels with a furnace, three sacks full of malt, a cup, a brass pot, a pan, a goblet bound with silver, a chafing dish, two silver spoons, and some other carefully specified goods. She also left brewing utensils to other heirs, giving a leaden vat each to her parish church, her parish priest, and two local monasteries, and leaving to her daughter, Isabel, two more leaden vats, a brass 3 gallon pot, a pan, a mortar and pestle, and the proceeds of one brewing.

[Bennett, p. 14]

For the first batch, I chose oak. To simulate some of the oak flavor that may have been picked up by fermenting in an oak vessel, I chose to boil a small amount of oak chips (available at better homebrewing shops) in a bit of water, and then added some of this water to the wort. Some care should be taken not to over do this, as the oak can have a surprisingly aggressive taste.

This addition of oak was criticized by Al Korzonas, who noted a very important point about oak in brewing: American Oak, which is what is often sold in brewing stores, has much more flavor than European Oak. He notes that several old English brewing books recommend against using American oak casks because of the flavor they will impart [Korzonas - oak]. I would recommend anyone who is considering using oak for a "more authentic taste" to read the article Mr. Korzonas wrote on the subject first.

Following this advice, I removed oak from the ingredient list for the second batch.

Quantities

I decided to use proportions of 3/4 malted barley and 1/4 unmalted oats (as a compromise to what is available), hard water, and ale yeast. But in what quantities? Again reviewing the Bennett quote from pp. 18:

Our most direct evidence of domestic brewing comes from elite households. In 1333--34, the household of Elizabeth de Burgh, Lady of Clare, brewed about 8 quarters of barley and dredge each week, each quarter yielding about 60 gallons of ale. Brewing varied by the season of the year, with vast amounts produced in December (when more than 3,500 gallons were brewed) and quite restricted production in February (only 810 gallons). The members of the Clare household drank strong ale throughout the year, imbibing with particular gusto during the celebrations of Christmas and the New Year.

[Bennett, p. 18]

The American Heritage dictionary lists 1 U.S. (modern) bushel at 2150.42 cubic inches, or 35.24 liters, and a U.K. standard bushel at 2219.36 cubic inches, or 36.37 liters [AmHer, "bushel"]. A bushel is 1/8th of a quarter; Bennett lists a quarter as being approximately 290 liters [Bennett, p. xv]. She also notes that a gallon in the medieval period in England was approximately the same size as a modern U.S. gallon, rather than the modern U.K. gallon (which is 25% larger).

So the Clare household recipe proportions were some 290 liters (dry measure) of grain, some 383 lbs., producing 60 gallons of ale. This works out to about 6.4 lbs. of grain per gallon of ale.

Not only are these large quantities of total grain used, they are surprisingly high quantities of grain per unit of water -- modern beer recipes generally run between 1 and 1 1/2 lbs. of grain per gallon. Clearly the medieval process was either quite inefficient, or the resulting wort was quite thick. After working on this project, I have found that it seems to be some of each.

While a thick wort will produce a high alcohol level, which helps preserve the ale, it also takes longer to ferment out. For this ale, I wanted to brew something that would finish somewhat more quickly. Bennett has some evidence of a weaker ale being produced around the same time.

... In 1282, when Robert Sibille the younger was presented at the court of Kibworth Harcourt for selling his ale at too high a price, the stipulated price left him little room for profit. Having paid 2s. for 4 bushels of malt and required to sell 5 gallons of ale for 2d., he would have had to draw 60 gallons from his malt just to recoup his investment. His ale, in other words, would have been very weak indeed and his profits very low.

[Bennett, p. 21]

4 bushels of my malt weighs 191.4 lbs.; this works out to a rate of 3.2 lbs. per gallon. While still quite strong by modern standards, this is half the rate of the Clare household recipe.

It is worth pointing out at this point that, due to the processes used, the Clare household ale would probably not be twice as strong as Sibille's ale. It would undoubtedly be quite a bit stronger, though. The irony is that Sibille was probably getting a better efficiency, in terms of sugar extracted out of his grain, than the Clare household was, at least for the initial running of the grain.

So for the first batch, I opted for something under the maximum concentration that Sibille could have brewed without losing money (according to Bennett). I used 3.2 lbs. of grain to draw approximately 2 1/2 gallons of ale. For the second, I tried to match the Clare household proportions, intending to use 12.3 lbs. of grain to draw approximately 2 gallons of ale, but ended up getting less liquid out than I intended in the first running, so this ended up somewhat stronger than the original.

I will also note here a nice rule-of-thumb. (I like rules of thumb like this; they are easy to remember and simple to describe to others.) Looking at the original Clare proportions, and taking into consideration how much water would be absorbed by the grain (but not released in the running), the rule-of-thumb is: 7 measures of water, added to 5 measures of grain (by the same volume measure), yield about 4 measures of ale, more or less. And the combined water and grain mix in the mash will occupy at least 8 measures when mashing (possibly 9 measures).

Techniques

Crushing the grain

In order to allow hot water to get at the starches in the grains, the grain must be crushed. It should not be powdered into a flour, however, as this can lead to a big sticky mess that one cannot get any liquid back out of. Ideally then, each grain should be crushed into two or three pieces, hopefully without ripping up the husk too much, as doing so will allow too much tannin to get into the liquid.

Medieval brewers crushed their grain using the same kind of stone mill as used to make flour (sometimes water powered, sometimes a hand-mill, or quern). I cannot believe that these brewers allowed the mill to grind the grain all the way to flour - rather they would adjust the grinding plates further apart in order to crush rather than powder the grain.

My hand-mill is a purpose-built home-brewing device that uses a knurled steel roller to crush grain against a flat plate. I recently had the opportunity to use a friend's bread flour mill - which uses stone grinding plates - to crush grain for homebrewing (I forgot to bring mine). We discovered that when we adjusted the grinding plates to be much further apart than usual, this mill produced results similar to my homebrewing; giving a bit more flour, but not much.

About mashing

Mashing is the process of converting the starches in the grains into fermentable sugars, using the enzymes that are in the malted grain. After being crushed (lightly ground), the grain is mixed with hot water (so that the mixture ends up somewhere in the 145 - 158 F range), and held in this temperature range for an hour or three. During this time, the enzymes will convert almost all of the starches into simple sugars that the yeast can digest.

A starch molecule is made of a long chain of simple sugars all linked together. There are two enzymes that work together to break this long chain down into small pieces. Alpha-amylase cuts long starch chains into smaller pieces, still too large to be digestible to yeast. Beta-amylase cuts very small pieces, simple sugars suitable to yeast, off the ends of the starch chains. So the two working together do a very good job of breaking down the long starches into sugars. Beta-amylase is most active at somewhat higher temperatures than Alpha, but there is a fair overlap in their useful temperature ranges [Noonan Lager, pp. 88-89]. The most important thing about all this to the brewer is that the higher the temperature mash, the sweeter the resulting beer will be.

Infusion mashing

Using an insulated vessel for the mash

Digbie writes, in "Scotch Ale from my Lady Holmbey":

Heat Spring-water; it must not boil, but be ready to boil, which you will know by leaping up in bubbles. Then pour it to the Malt; but by little and little, stirring them strongly together all the while they are mingling. When all the water is in, it must be so proportioned that it be very thick. Then cover the vessel well with a thick Mat made on purpose with a hole for the stick, and that with Coverlets and Blankets to keep in all the heat. After three or four hours, let it run out by the stick (putting new heated water upon the Malt, if you please, for small Ale or Beer) into a Hogshead with the head out. ...

I should also point out that the normal batch size was quite, quite large by modern homebrewing standards (though small compared to modern commercial practice). Water has a large thermal mass, which is to say that it holds heat pretty well. It is also not the best conductor of heat, so if one has, say, a Hogshead (approximately 64 gallons) of hot water, in an approximately cubic barrel, it can take a long time for it to cool down. Digbie, slightly later in the same recipe writes:

Then put it again into the Caldron, and boil it an hour or an hour and a half. Then put it into a Woodden-vessel to cool, which will require near forty hours for a hogshead.

So when scaling these recipes down to smaller sizes, it is quite reasonable to mash in an insulated vessel. Not only because Digbie instructs us to in his 17th. C. recipe, but also because the thermal mass and poor thermal conductance of the large amount of water in the original proportions tend to insulate the interior portion of the mash, and this can be effectively simulated by using an insulated vessel.

Successful infusion mashing without a thermometer

Of course, neither the thermometer nor hydrometer were invented by 1600. So I had to find a way to get the mash temperature right without resorting to the the modern technique of directly measuring it.

Digbie tells us that "When all the water is in, it must be so proportioned that it be very thick." In addition, William Harrison, in describing how his wife makes beer, writes:

... The first liquor which is full eightie gallons according to the proportion of our furnace, she maketh boiling hot, and then powreth it softlie into the malt, where it resteth (but without stirring) untill hir second liquor be almost ready to boile. ...

[Misc-4]

I tried this on a very small test batch of two pounds of grain, in a small insulated cooler, with boiling water. At the time I found that adding 3 cups of boiling water made the grain both a bit too cool, at around 145 degrees F., and too dry, with some grain still dry. 4 cups, however, left the grain just a tad too high, at 160, and was very thick.

Later, Eric Rhude reported on the medieval brewer's mailing list that just ladling the water in a bit at a time worked fine for him [Rhude].

So for these batches, I tried pouring in the boiling water over a height of some two feet, a quart at a time, for a total of 6 quarts worth (including about 1 1/2 quart to cover the false bottom described below). And then in order to let the enzymes have some chance at being too cool in some places, and too hot in others, I didn't stir it up until half an hour after initially starting the mash. And then I let it sit a good long time to let the enzymes do their work.

I'm delighted to report that this worked great. Though I do not have a thermometer, I do have my fingers. After stirring up the batch, it was sufficiently hot that I could stand to dip my finger-tips into it for only a second or so. In a completely different context and use, Norm Thagard and Nelson Pass reported that an object that is 50 deg. C is very hot, and 55 deg. C. is untouchable [Thagard]. I have found that my fingers will put up with a bit more heat, so that 65 deg. C, or 149 deg. F, is almost too hot to touch.

Aside from burning my fingers, the runnings from the malt were sweet and sticky, and after removing the liquid, the grain had visibly lost some starch.

To simulate the mash tun described in Digbie (above), I used a 10-gallon Rubbermaid-brand water cooler to mash in, with a Phil's Phalse Bottom(tm), a false bottom. This is a slightly downward-dished piece of plastic with a huge number of small holes in it, and an elbow that directs a siphon tube into the space trapped between the false bottom and the actual bottom of the cooler. This has the effect of holding the grain away from the inlet to the siphon tube, and allows liquid to be easily removed. This is essentially like a permanently installed colander.

No Recirculation

In modern brewing, it is customary to recirculate the first bit of liquid in order to make a filter bed out of the grain close to the false bottom, so that the liquid that is drawn off is fairly clear. There is, however, no evidence of this practice in any period references that I am aware of. In the absence of evidence, I chose not to recirculate any of the wort in making these batches.

No Sparging

Sparging is the technique of adding additional hot water to a draining bed of grain in order to rinse more sugar out the grain. It is commonly done in modern brewing, but there is ample evidence that this is a post-period innovation. The Oxford English Dictionary lists the first use of the term sparge, when referring to brewing, at 1839, and then again at 1885 [OED, v. 16, p. 117]. Further evidence of the importance of this innovation can be found in Noonan's book Scotch Ale. Noonan quotes W. H. Roberts, a Scottish brewer, writing in 1847:

The process of sparging is, in my opinion, decidedly preferable to a second mash for ale worts, and has ever been considered in this light by the whole of Scottish brewers.

[Noonan Scotch Ale, pp. 90]

I can attest from experience that sparging is definitely an innovation, allowing a much greater extraction rate from the grain. All evidence that I have seen, however, indicates that it is a much more modern innovation, and not appropriate to even Elizabethan-era recreation. As discussed above, however, not using this technique has a profound effect on the quantities of grain required to produce a given strength of ale or beer. By using modern temperature control on the mash and sparging, I need less than half the amount of grain that is required by the older techniques. But then I also get a more modern-tasting result.

So I didn't sparge; I simply drained out the liquid that was in my mash.

A second running

The general mashing technique used by English brewers in the Elizabethan period was double (or triple) infusion mashing. In this, after the first infusion as been done (as described above) and the liquor has been drained off, a second batch of hot water is added to the grains, which are again allowed to steep. The second batch of liquor is then drained off and fermented. For very potent beers or ales, a third running would be performed in the same way.

These second and third mashings are mostly useless for enzyme activity - the enzymes have mostly quit by the time the first mashing is over. But not all of the sugars will be collected in the first running. These second mashings serve to rinse more sugar out of the grain, giving weaker beers or ales for the effort. This helps improve the over-all efficiency, but not as much as sparging. Adding together the combined amount of sugar I got out of the grains from both runnings of the second batch, I still only got about two-thirds of the efficiency that I would have using modern techniques. This is an important point to keep in mind even for recreations of late-period beers: The efficiency of the process is lower; the efficiency of an individual running is much lower.

I have no justification for using a double-infusion technique on a pre-Elizabethan ale, other than that doing so does not change the results of the first running one bit, and there is still a substantial amount of sugar still trapped in the grains after running off the first batch; it would be a same to waste this by throwing it out. So for the second recipe, I did a second infusion as well, and made an ordinary ale out of this.

No Post-mash Boil

This is the important difference between medieval English ale brewing technique, and both beer brewing and Elizabethan ale brewing: medieval English ale was not boiled after the wort was strained from the grains.

Judith Bennett reports that many people brewed ale for sale, at least in more rural communities:

Commercial brewing was very widespread, especially in the countryside. In Brigstock before the plague, more than 300 women -- about one-third of the women who lived on the manor -- brewed ale for sale. In Alrewas (Staffordshire) during the 1330s and 1340s, between 52 and 76 brewers sold ale each year (in a village with about 120 households). In Wakefield (Yorkshire) between 1348 and 1350, 185 women -- accounting for almost one-third of all women -- brewed for sale. ...

[Bennett, pp. 18--19]

Bennett suggests that the longevity of beer, especially in comparison to that of ale, is due to the addition of hops. Hops clearly help -- the alpha acids in hops that give beer its bitterness also have a preservative effect [Smith pp. 24--25].

However, I do not believe that is the complete story. It is worth noting that Digbie, in "Scotch Ale from my Lady Holmbey", concludes:

It will be fit to broach after a year; and be very clear and sweet and pleasant, and will continue a year longer drawing; and the last glass full be as pure and as quick as the first.

Further evidence of this difference can be found in Smith's book on the history of Beer:

... Overall it was a thickish liquid, low in alcohol from the incomplete ferment. One person from the 1200s described it as "for muddy, foddy, fulsome, puddle, stinking; for all of these ale is the only drinking." It was also well described in rhyme about a notorious Cornish ale cited by Andrew Boorde in 1540. Ich am a Cornishman, ale I can brew

It will make one cacke, also to spew.

It is thick and smokey and also it is thin

It is like wash as pigs had wrestled there in

[Smith, p. 24]

I suggest that besides the hops, one particular aspect of adding the hops significantly increases the keeping time of beer or ale: the post-mash boil.

In brewing a beer, after the wort has been run off the grain, it is put in a big pot and boiled some more and hops are added. The heat of the boil is necessary to dissolve the hop alpha acids into solution effectively. But the other thing that happens early in the boil is that many of the proteins are cooked (and later fall out of solution). When this process of cooking the proteins culminates, the wort will foam up aggressively, and the brewer must be careful not to let the wort boil out of the pot, all over, and make a big mess.

I submit that if the post-mash boil is not done, then these proteins will stay in solution in the ale, and give extra nourishment not only to the drinker, but also to some types of bacteria that might like to infect the drink. Since medieval ale apparently spoiled easily, it probably wasn't boiled the second time after the mash.

That the ale wort was not boiled is stated by Bennett, who then adds into the cost of brewing beer an increase for the cost of fuel [Bennett, pp. 86--87].

This argument against a post-mash boil is, however, speculative. Part of the point of brewing these batches was to see if the now customary second boil was necessary, or if good ale could be produced without this step. So far, the results seem to back the historical evidence: the first batch was quite cloudy and tasted very much like liquid bread on the third day after being made. Despite this, it was quite drinkable and refreshing. Despite modern care with sanitation, it started to sour on the fourth day, and was fully sour before it started to really clear. (It ended up about as sour as Rodenbach Red Ale; not as sour as Rodenbach Grand Cru, and not even close to as sour as Cantillon Gueuze.)

Cooling

Digbie describes slow-cooling (in a large vat, for some 40 hours). Markham describes a quicker cooling technique involving pouring the hot wort into a shallow open vat. The problem with the open vat method is that in exposing the wort to a lot of air, one is almost sure to inoculate the wort with who-knows-what type of undesirable organisms [De Keersmaecker]. This works great for some Belgians, who deliberately inoculate their beer, lambic, with whatever happens to be floating by in the air that day. Unfortunately, I live in the wrong micro-climate to try such things. So I opted to let the wort cool by just sitting, closed, over night.

Fermenting

After the wort is cool, a modern home-brewer would pitch in the yeast, make sure the wort is well aerated, and put on a blow-off tube or fermentation lock. Digbie and Markham suggest some sort of blow-off technique.

On the other hand, many professional brewers, using equipment that is now considered antiquated, ferment in large open vats.

For these batches, I opted for sort of a compromise, and used 3- or 4-gallon plastic fermenters, either with a lid that does not quite seal or with a plastic bubble-lock. I kept them closed to prevent possible infection, though that doesn't seem to matter with the addition of the Lambic dregs.

Implications for recreational brewers

To the modern brewer, the quantities of grain described in these sources seem extraordinarily large. However, the process is so inefficient that large quantities of grain are required to produce ale of adequate strength using these older techniques. The upshot of this is two-fold. First, if one is trying to recreate an all-grain beer or ale, one should plan on using a lot of grain. Second, if one is attempting to adapt an (Elizabethan) English beer recipe to the use of modern malt extract, one should keep firmly in mind the low efficiency of the boiling water infusion mash technique. So whereas a modern extract brewer would use 2/3 of the malt extract (by weight) as in a modern all-grain recipe, they should use approximately 3/8 as much extract as grain in the original recipe. (They should also keep in mind that virtually all period recipes measure the grain by dry volume rather than by weight, and convert appropriately.)

I hasten to caution that an extract-based recreation of a late-period English beer won't be as accurate as an all-grain recreation using appropriately period mashing techniques. The mash used is much thicker and hotter than used in commercial brewing (and thus malt extract production). As a result, the beer will have a much different character: the period all-grain beer will be sweeter and have much more "body" due to the high temperature of the mash. Still, the recreation of such a beer won't be bad, merely not as good as it could be.

On the other hand, I do not think that one can properly recreate a medieval ale using modern malt extract. Unlike the mash process used in this recipe, the extract will have been boiled as part of the manufacturing process. This boiling will cook out many proteins that are suspended in the wort, and as a result greatly change the character of the ale. So while an extract-based ale will be ale in the sense that it contains no hops, it wouldn't be particularly medieval in character.

Conclusions

Plus, it is actually medieval.

Acknowledgements

References

[AmHer] Davies, P., ed. The American Heritage Dictionary, 1970 Dell Publishing [Bennett] Bennett, J., Ale, Beer, and Brewsters in England (Women's work in a Changing World, 1300--1600), 1996 Oxford University Press, New York, ISBN 0-19-507390-8. [Bloom] Marc ("Red") Bloom, private communication, 1998 [De Keersmaecker] De Keersmaecker, J., "The Mystery of Lambic Beer", Scientific American, August 1996, pp. 74-80. [Digbie] Digbie, K, The Closet of the eminently Learned Sir Kenelme Digbie, kt., Opened..., 1669, in Miscellany from D. Friedman & E. Cook

The beverage recipes from this are also available in [Renfrow]. [Harrison] Harrison, J, An Introduction to Old British Beers and How to Make Them, 1991 Durden Park Beer Circle [hist-brew] Historic home-brewers' mailing list. To subscribe, send email to majordomo@pbm.com containing the words "subscribe hist-brewing" (or "subscribe hist-brewing-digest" for the digest form). [Korzonas - letter] Al Korzonas, private communication, 1998 [Korzonas - oak] Al Korzonas, Oak in Brewing, 1998, http://www.brewinfo.com/brewinfo/articles/oak.html [Ligas] Ligas, M., "Yeast Management Techniques", Zymurgy, Vol. 17 No. 2, Summer 1994, pp. 38--43. [Misc-4] Harrison, preface to Hollinshed's Chronicles, 1587, in Miscellany as "Misc-4," from D. Friedman & E. Cook

The text also appears in [Renfrow, pp. 4--5] [Markham] Markham, G., The English Housewife, Best, M. ed., 1986 McGill-Queen's Press. (originally published 1615, 1623, and 1631.) [Noonan Lager] Noonan, G., Brewing Lager Beer, 1983 Brewers Publications. [Noonan Scotch Ale] Noonan, G., Scotch Ale, 1993 Brewers Publications. [OED] The Oxford English Dictionary, 2nd edition., 1989. [Rajotte] Rajotte, P., Belgian Ale, 1992 Brewers Publications. [Renfrow] Renfrow, C., A Sip Through Time, 1995, self-published [Rhude] Rhude, E., <ateno@panix.com>, "hist-brewing: ancient methods (fwd)", historic brewer's mailing list, 14 Apr 1998 [Thagard] Thagard, N., and N. Pass, "Build the A75 Power Amplifier", The Audio Amateur, Four: 1992, (also available from the Pass Labs web site at http://www.passlabs.com) [Smith] Smith, G., Beer (A History of Suds and Civilization from Mesopotamia to Microbrews), 1995 Avon Books

Last modified Dec. 31, 1998



Tofi Kerthjalfadsson (Paul Placeway)

pwp+ (AT) cs dot cmu dot edu

Copyright (C) 1998 by Paul W. Placeway.

The author gives permission for this to be reproduced for personal use in any form, so long as the complete text, from title through this notice, is included. For other uses, please contact the author.