Lacock Abbey Brewery Further Investigations

Lacock Brewery Itemised
Figure 7. Brewhouse Equipment. Reproduced by kind permission of the National Trust.

Vessels measured in metres. Usable volumes apart from coolers estimated at 10cm or 4inches below the rim. This may be too high however it gives a rough estimate of usable volumes.

1.   Copper Boiler.
1.430 Diameter top, 0.99 Diameter bottom, 0.874 Depth.
Total Volume 0.9834m³. Estimated usable height 0.864 metres therefore usable volume 0.9714m³, 971.4 litres.
Copper set in masonry. Heat source is a furnace situated immediately below the copper and accessed through the wall in the adjacent bakery. A damper to control the flow of hot air in the flue is situated just above the copper. The bakery no longer exists although its flue is in the wall and appears to connect to the boiler flue and a common chimney. A rectangular mark in the copper bottom indicates the application of heat from the grate below. An examination by endoscope through the grate (the firebox door could not be opened) indicated a flue exit to the left.

2.   Wooden Chute
Placed under the brass tap from the copper to the cooler. For emptying hot wort into the cooler.

3.   Lead lined Cooler with Filling Chute.

Length 4.017, Depth 0.2, Width 1.957.
Total Volume 1.5722538 meters .

Sources state that coolers should not be more than 3 to 4 inches full.
Going on:

6 inches deep approx. the working volume is 1.17919035 m³, 1179 litres.
5 inches 1.02196497m 3, 1022 litres.
4 inches 0.7861269m 3, 786 litres.

4.   Gyle Tun
Top Diameter 1.823, Bottom Diameter 2.015, Depth 0.527.
Total Volume 1.5 m³.
Estimated usable volume leaving space for yeast froth.
1.4705 m³, 1470.5 litres.

5.   Bucket space under Gyle Tun Tap.
Diameter 0.686, Depth 0.456. Total Volume 0.05618m , 56.18 litres.
For collecting fermenting beer in a pail to be transferred to casks for cleansing.

Brewhouse Water Supply

There is no surviving evidence of a piped water supply to the copper. It is inconceivable that a house with a good supply of running spring water would not have made provision for the brewhouse. A cut-off lead pipe protrudes from the wall above the cooler which may have continued to the copper and also provided water for cleaning.

Furnace in the Bakery

The boiler (copper) and fire as set in masonry is inherited from Roman lead boiler technology. Enhancements in 16 th century England are a copper boiler (not lead) and a complex flu situated in a sophisticated brick support and surround. Not being able to open the grate door due to its fragility, I used an endoscope through the grate to examine the firebox. The copper is supported on brickwork in which a flue appears to open to the left. The passage of this flue through the brickwork is not known, but the upper flue with the damper is a diagonal from the other side of the copper. Because of heat marks on the base of the copper it is thought that the only area subjected to heat is the bottom surface of the copper. Another flue appears high in the furnace area against the wall. This goes straight up and may be connected to the upper diagonal flue, possibly as a further draw to the fire.

Furnace in the Bakery
Figure 8. Grate with Firebox door. Reproduced by kind permission of the National Trust.

What appears to be a large chimney-like structure on the outside of the wall, with a chimney on top, is a Tudor Long Drop, a toilet accessible from the top floor. The exit for smoke and gases is unknown but must be somewhere in the lining of this structure. Furthermore, there is no apparent exit for the contents of the toilet either. Could it be below the present ground surface? There is no knowing without professional archaeology, or just a spade. The brewery, unusually, has no mash tun or underback. Normally, malt is put in the mash tun and hot water from the boiler is poured on top, or the water can be first in the mash tun before mixing in the malt. In this brewery water has to be heated in the boiler and malt mixed in. The boiler empties directly into the cooler via a wooden chute, effectively making this vessel dual purpose as boiler and mash tun. This brewery was built at a time when the fashion for hops was established. There is no way to separate the wort from the malt and transfer back into the boiler for a hop boil. The only way to introduce hops or any botanicals is to boil them in the original water or mix them into the mash. A hop boil in the wort is impossible, so we are back to making original ale, how did the brewery make beer?

Copper and Flue Schematic
Figure 9. Copper with flue schematic viewed from the bakery.

Lacock Further Investigations

It is inconceivable that a brewery built in the 1540s, or even more inconceivably in the 1700s, did not have a mash tun and underback. The earlier recorded breweries belonging to Richard de Long in 1335 and Robyn Robinson in 1486 both had mash tuns and underbacks or tap-troughs (Henry Thomas Riley, Memorials of London and London Life 1868). Inventories of the Lacock cellars detail strong and small beer and invoices exist for the purchase of hops and making beer, so wort boiling must have taken place. Yet the existing brewery equipment consists of:

Copper set in masonry at a height of approx. 2900 mm with grate and flue on the other side of the wall in the bakehouse.
Wort chute from copper tap to cooler.
Large lead lined cooler.
Gyle or fermenting tun.

Bills for work done in the 18th and 19th centuries clearly indicate that the brewhouse contained a more complete brewery.

Relevant documents referring to the missing elements include:

           John Bankes repaired the underback in the brewhouse on November 28 th 1745.

David West was occupied for 5 days in October 1750 in “making the underback”.

In November 1758 Peter Cott took down the pump in the brewhouse. Presumably this was for repairs as, he replaces it a few days later as well as making a stand for the furnace. In 1759 he charges for 6 foot of deal plank used in the bottom of the mashing tub, 5 foot of 4 inch oak plank used in the bottom of the pump and 3 tun plugs for the cooler.

A bill from George Banks for work in the brewhouse 1842 – 44 details 2 ½ days for a man to work at the underback and paving in the brewhouse. The large amounts of lime detailed indicate the securing of masonry/stonework.

In addition to the above works, late 18 th and early 19 th century brewhouse inventories clearly list the missing items.

Brewhouse 1778
a Copper & Grate (as fixt)
a Large Cooller cased with lead
An Underback under Ditto
a Mash Tub & under Back with Pump to Ditto

Brewhouse 1788
2 Pailes and one Boule
1 Mash tub and two Stirring Sticks
1 Under Deck (underback) and Pump
1 Cooler and Under Deck (gyle tun) for wort
2 Civeing tubs (Kiving, Kieving) [1]
2 Hopstrainers
3 water Shoots and Bowle
1 Fire Shovel Pocker and Rake
5 Barm Spouts
2 Ovil tubs and two Stools
1 Tub for carrying the wort to the Cellar.

[1] Keever or Keeving tub. A shallow wooden vessel or tub for holding liquids – OED. In November 1748 David West set three hoops on three basin civers.

large Copper and Grate as fixed
a Large Mashing Tub
1  Stirring Stick
An oval cooling Tub
1 Under Deck (underback) and Pump
A large cooler lined with Lead
1 Under Deck for Wort (gyle tun)
2 Kiveing Tubs – 1 Hop Strainer (wore out)
Fire Shovel Poker and Rake
3 Stools
2 Carrying Tubs
4 round Tubs – 3 Water Shutes
A large Brass Skimmer
A Pail and 2 Lade Pails

Brewhouse 1827
1 large Copper Furnace & Grate
Large Mash Tub & stirring Stick
Do. Underback & Pump to do.
Do. Cooler lined with Lead
1 do. & under to do.
2 Kiving Tubs
2 Carrying do.
4 Round do.
3 Iron Bound Casks
2 Liquor (water) Shoots
3 Stools & Hop Strainer
Iron Poker

Brewery in the Cloister – The Chaplain’s Room

Given that inventories indicate a more complete brewery, was there another brewery in another location? It has been suggested that the southernmost room in the west range was a brewery because a drain exists under the floor and a 14 th century chamfered arched doorway has been widened in the circular shape of a cask. The implication is that if the room was not a brewery, at least it might have been a cask storage area. Casks are normally moved by rolling or on a mobile platform and the shape of this cutting implies that casks were dragged lengthways on the ground or pulled lengthways on a sled, the widest part of the cask being the bilge or pitch, or mid-point from both ends. The diameter of the opening is 33 inches and widens the door jamb to the width of the entry passage beyond (figure 9). As a brewer and erstwhile drayman, I know the difficulties of dragging a cask lengthways through a narrow passageway, which in this case is 7ft long. Although it must be stated that the passageway does not appear on the pre 1723 plan, it would be pointless to hack an opening for a smaller width of cask, therefore the size of the operative cask would have to just fit the door and passage. A butt has a diameter at the pitch (widest part) of 33 inches. (Kilby 1971, 61) The weight of the liquid would be in excess of 1080 lbs (108 gallons, 450litres). I can’t determine the weight of the empty cask, but a hogshead (half the size) is about 520 lbs; I estimate a butt to be at least 750 lbs. That makes a total weight in excess of around 1080 + 750 = 1830 lbs (830 kg). Hardly a practical job to do regularly. In any case, the only size of cask in the cellar inventories is a hogshead which, containing 54 imperial gallons has a diameter of only 28.5 inches. Whether Lacock was using the ale or wine gallon we do not know, but the hogshead must have been smaller than any manner of butt. Brakspear is detailed in his descriptions, commenting on the fireplace next to this door being “mutilated”; he makes no mention of the hacking of the chamfer (Lacock Abbey, Wilts. Published in Archaeologia Volume 57,1900, Pages 125-158). It is highly likely this mutilation was made post Brakspear in the 1900s, after a time when any brewery had ceased production. Clearly the reason for the shaping of this doorway is obscure and unlikely to be for passing casks, particularly when another door in the courtyard (not associated with beer) is similarly shaped and is wide enough for any cask without modification. Yet there may be some truth in the passing of casks theory. The practice of modifying doorways in this way may have been a common phenomenon, Figure 11 shows a similarly modified door to a wine cellar in the old town hall at Regensburg! The reshaping of the door is inconclusive as to whether the room was a storage area for casks; whether it was a brewery is another question. Within the Chaplain’s Room are two wall paintings on original plaster. Brakspear dates the red figure of St Christopher with the infant Christ in his arms as not much later than the thirteenth century. The blue sketch is a representation of St Andrew with his arms extended in the form of a cross that bears his name. The representation of a rabbit, associated with medieval celebration of Easter is scratched into the plaster. If there had been a brewery in this room, condensation would have destroyed these earliest images and it is highly probable that the entire walls would have been whitewashed.

Barrel Door
Figure 10. “Barrel” door. Reproduced by kind permission of the National Trust.
Regensburg Town Hall
Figure 11. Wine Cellar, Regensburg Old Townhall.

Mash Tun, Underback and Pump

There was a pump at least from 1758 and inventories from 1778 to 1827 record all three items. There is very little room for these items so where might they have been? First take away the later wooden structures; the board from the bottom of the copper housing to the cooler, the wooden stairs covering the stone steps and the balcony screen.

Within the area between the copper base and the cooler is a wedge shaped stone infill which extends to the cooler at the wall and diagonally to the steps. I believe that the brewery was mothballed, crumbling stonework consolidated with the infill, and access made safe with the wooden structures of steps and balcony. The steps to the bottom of the flight are narrowed to allow access to this area and taking out the stone infill makes just enough room for a mash tun and underback. The inventory of 1778 places the underback under the cooler, the mash tun would be above and overlapping to drain into it. The pump would take wort back into the copper for the boil. Up to three liquor chutes were in use so that the wort could be channelled to different vessels from the copper.

Alternatively, the mashtun and underback may have been on the other side of the steps. The cooler and gyle tun sit on a lower area which feeds into an outer drain which may have originally emptied through the wall but now has a grill in the bottom of the channel, indicating a drain under the floor. The infill comes right up to this channel which runs under the steps to a sunken area the other side of the steps. The area is occupied now by a stone bath and two casks and the existence of a large drain area implies that this area was used for liquid operations. Could the mash tun and underback have been sited here? The mash tun would normally have been directly under the copper tap on the other side of the steps, but as the copper tap is directly over original masonry there had to be a chute for all tap operations. At one inventory there were three chutes and one may have been shaped to feed across the stairs. Admittedly, this solution is unlikely, the draining area most likely used for cleaning and filling casks from the gyle tun before transport to the cellar.

Figure 12 shows where I think is the most likely position of mash tun and underback.

Lacock Brewhouse Scematic
Figure 12. Lacock brewhouse with putative mash tun and underback.

Brewery Performance and Virtual Brew

Not knowing the size of the mash tun, it is impossible to estimate the maximum volume of malt and strengths of beer/ale produced. However, it is possible to virtual brew using Bankes’ 1744/45 brews of 24 bushels of malt and Cripps’ 1754 brews of 8 bushels of malt and 3lb of hops. The usable capacity of the gyle tun is 1470.5 litres. If the cooler is filled to capacity, that is with the slowest cooling, it is large enough to take the whole of the capacity of the gyle tun. The usable capacity of the copper is 971.4 litres. If the liquor was boiled then let into the mash tun to cool until reflection of the brewer’s face could be seen, it would go from 100°C to approx. 76°C and lose about 1.7% volume. Therefore the maximum of liquid at mash temperature would be 954.5 litres, assuming that cold liquor was not added for cooling. Adding 3 quarters (24 bushels) of malt at 310 lbs per quarter (422 kg) with extract potential of 58% and stirring (mashing) results in a runoff of 532.5 litres at a specific gravity of 1.085. Boiling for an hour and accounting for evaporation in the copper and cooler the final wort could be 441 litres at 1.104 sg. Further additions of liquor to the mash could be in various volumes but assuming equal volumes to the first, the mash tun and cooler could hold over three worts combined. All three worts could be:                                 

Virtual Brew 1

Abvs are tentatively derived from Richardson’s table of attenuation, (John Richardson, The Philosophical Principles of the Science of Brewing 2nd Edition 1798). In practise there could be much variation.

In theory there could be three separate beers of diminishing strength. With one gyle tun successive brews would take longer than a day and considering that Bankes sometimes had only one day between brews, on those occasions he would have to combine the worts.

Bankes’ brew is a stiff mash of 2.2 litres/kg which would produce a decent strong beer or ale with three worts combined, especially as worts two and three used less liquor; a small beer would be impossible without a separate third mash. Cripps’ brew of 8 bushels (1 quarter) would produce a very watery mash of 6.8 litres/kg if the maximum amount of liquor was used.

The flexibility of the plant becomes apparent being able to brew strong to small beer and combine worts for intermediate strengths. Using the maximum possible liquor Cripps could make small beer with two worts combined with an abv under 2% and IBUs of under 10, but if Cripps had chosen to make one hogshead, the first wort would have been around 1.077 sg, capable of producing a beer of 6% to 7% abv with IBUs of over 40.

N.B. The above examples have been made from the maximum possible liquor that the copper could deliver against stated malt quantities. There are so many variables that the results must be taken as a rough guide to what the plant is capable of. Malt weight per quarter and extract values are taken from an extensive study which will be published in due course.

The courtyard was constructed in Sharington’s time, and it has been assumed that the brewhouse, with its equipment is original from that time. Yet it has been noted that the original construction of the abbey is in stone. The appearance of the furnace in the bakery indicates a modification of the wall to accommodate the brick furnace, iron grate, flues and copper tank enclosure. The similarity of the brickwork, copper and grate to that of Charlecote 66 miles away indicates that the construction belongs to 18C technology and possibly may even have been constructed by the same builders who updated Charlecote brewhouse. After the construction of the brickwork and copper, it may have been decided that the cooler needed to be bigger and the lower steps to the copper cut away to allow access to the area between the cooler and the copper where the mash tun, underback and pump were. Evidence points to the upgrade being made by John Ivory Talbot and beginning brewing in 1721, the brewery then providing the house with a good supply of strong beer, small beer and ale until around the time of the death of Lady Elizabeth in 1844.