All The First Person Accounts of Jamaica Rum Production Made Accessible

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Welcome to the round up of papers on Jamaican (and adjacent) rum production. The goal here is to put a lot of resources in one place as a foundational tool for creating a rum production renaissance. A few parts are still missing, but I’ve run out of time to work on it for the moment.

Quite a few of these papers have not been seen in generations, and a few others were recently only known to a small handful of people. We are about to find out what happens next when a topic thought to be arcane becomes the best documented of all spirits traditions. It is unprecedented for a community of spirits enthusiasts knowledge to grow so significantly in a short period. No major book has been written about rum since I started collected papers. So what happens next?

This is also a drinking game. In the documents, when anyone says empyreumatic, you drink! When Leonard Wray says peculiar, you drink twice! Oh yeah, and nothing but Jamaica rum! See if you can make it to the 20th century!

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1754, Thomas Thistlewood. Thistlewood papers. [citations collected by Nuala Zahedieh. I better need to update and catalog these.]

• Contained in the Bodleian Library, Oxford, “Clarendon deposit”. Or Beinecke Library “Thistlewood papers”
• Cited extensively by Zahedieh N (2021). A Copper Still and the Making of Rum in the Eighteenth Century Atlantic World. The Historical Journal 1–18. https://doi.org/10.1017/S0018246X21000212
• Wedderburn reference—> J. Wedderburn, account current with estate for 1778, Clarendon deposit, b. 37. P
• In 1754, Thistlewood tried adding pimento broth to the wash. Diary, 4 Apr. 1754, Thistlewood
  papers, box 1, folder 3, p. 87.
• Thistlewood papers, box 11, folder 81.
• Employed two enslaved African distillers Augustus and Primus (who likely invented the pimento broth idea).
• Extra notes on rum: Mr Richard Beckford’s instructions, Thistlewood papers, box 11, folder 81, p. 26 [possibly regarding cleanliness.]
• Anecdotes provided: In 1754, Thistlewood reported that a blockage in a worm had halted production. On advice from a local
  coppersmith, he turned the worm upside down, and poured in boiling water. ‘[I] then used a stick with cotton wrapped round it to force on ye water, in imitation of a syringe, by which a blowing forced out a large piece of rag, cow dung etc.’ He added that regular cleaning involved ‘burning the worms as many times round as they had turns (laid upon planks of wood lengthways)’. Diary, 14 Jan. 1754, Thistlewood papers, box 3, folder 4.
• 6 James Somerville to Neil Malcolm, 16 Dec. 1775, Forbes papers, A727.26; ‘An essay on the management of rum distilling’, Thistlewood papers, box 12, folder 88, p. 33.
• Mesopotamia orders 1000 gallon still: Barham to Forbes, 9 Sept. 1775, Forbes papers, A 727.1471. The monster was expected to weigh between 28 and 34 hundredweight (1.4–1.7 tons): Forbes to Barham, 15 Sept. 1775, Forbes papers,
  A727.25. [citation from Zahedieh
• Another spectacular Zahedieh note: Planters repeatedly emphasized the importance of thin copper. In 1774, Florentius Vassal
  ordered a 400-gallon copper which was to be as ‘thin as possible and well and smoothly polished’:
  Orders received by George and William Forbes, 5 Jan.–27 Dec. 1774, Forbes papers, A727.1455.
  Barham reported that the London coppersmiths were falling short of former standards when vessels were ‘not more than two thirds of the thickness of the present sort and consequently of better metal workmanship’. Barham to Forbes, 9 Sept. 1775, Forbes papers, A727.1471.
• Thistlewood was the distiller at Westmoreland.

1765, Samuel Martin of Antigua. Essay on Plantership. [also: Essay upon Plantership]

• Promotes cleanliness
• Compares lees (dunder) to yeast or barm
• Never uses sour dunder.
• Throws away material and restarts upon souring.
• Rule of thumb: one third of scum from the cane-juice, one third of water from copper washing, one third of lees. After 24 hours it is exited to the first charge of molasses; 6 gallons for ever hundred gallons of wash. First 3 gallons after 24 hours, second three gallons after another 24 hours. Mentions a taste as a decision making queue between the first and second dose of molasses.
• However: “but now I am convinced by repeated experiments, that by setting the wash and the quantity of melasses at once (as is the constant practice both in Old and New England) is the surest and best method of producing rum;”
• Mentions 5-8 days ferments.
• Puts dunder in fermenters as soon as they are cleaned after distillation to prevent souring.
• Feels time is misspent grinding rotten canes (no doubt others were doing it).
• Explains a unique visual clue of “ripe for distillation”: Those appearances are suitable only to a very weak wash; but if it be rich, it cannot be fit for distillation, until quite flat and a cream upon it. (cream?)
• Stream of spirit running from the worm of a still of 500 gallons out to be near as big as a man’s little finger; (what he goes on to explain about the ABV changing regards challenging the pot still’s natural reflux with too much engergy and therefore reducing the ABV.
• Mentions demand of the London market for a fiery spirit because it will bear more adulteration.
• Very clear British Museum 4th edition copy.

1791, John Baillie. The Jamaica Distillers Directory: A Treatise on Fermentation, Distillation and Rectification . . . .

• This is a lost text, but there are hints of where it may be found.
• Possibly sold as a subscription newsletter, but may exist as a bound collection dated 1821.
• John Baillie was the proprietor of the Roehampton estate and attorney for Georgia (famed for a heavy rum at the end of the 20th century)
• Citation collected by Lowell Joseph Ragatz who compiled a bibliography from 69 institutions but does not specify the institution. Ragatz corresponded with Frank Cundall, the Jamaica historian, but it does not appear in Cundall’s bibliographies. I bet it is from a British library but maybe private and not public.

1801, Clement Caines. Letters on the Cultivation of the Otaheite Cane; the manufacture of sugar and rum, the saving of melasses, the care and preservation of stock, etc.

• The author writes from St. Kitts, but mentions some of his advice coming from Jamaica.
• This may represent the end of an era, before Bryan Higgins introduced a lime obsessions to the West Indies.
• There are no mentions of lime and the authors does not use the term dunder, but instead uses lees.
• Advises setting ferments richer that others advocate.
• Introduces rule of thumb that low wines should always be one cane more than the fraction collected as rum.
• Ties size of the low wines fraction to the quality of dunder.
• Advises using dunder over and over across seasons.

[What needs to go in here or perhaps above Clement Caines is the works of Bryan Higgins who introduced lime based processes to Jamaica. When we consider all the literature, a Higgins era starts to appear that lasted from roughly 1800 to the 1870’s and beyond in common clean fermentations.]

1821, William Hylton Distillation of Rum or Spirits As conducted in Jamaica, with remarks on Cisterns or Vats, and Stills.

• Published in the journal, The American Farmer.
• Promotes the idea of shallower vats.
• Notes the use of large pot stills.
• Author acknowledges that molasses must be fresh and that American rum has hogo (a negative to the author) because the molasses turns acid during its voyage.
• Describes tenuous economics and mentions setting at 14 baume because of a shortage of fuel despite it being unprofitable. Does that mean they could have set higher (slowing down fermentation) but chose not to because of a vat capacity limitation?
• describes a 1600 gallon pot still design he commission in 1790 and may have influenced the adoption of flatter stouter pot stills with copper capitals instead of pewter.

1823, Thomas Roughly. The Jamaica Planter’s Guide (Chapter VII).

• Starts with attention to cleaning the still.
• Fills cisterns at the start of the season with wet green mill trash to “sweat and warm the cisterns” promoting fermentation.
• Warms the cisterns at the beginning of the season with a fire, matching descriptions by Burton.
• Does not use stale dunder from previous crop.
• Describes measuring rod for setting up vats.
• Describes distillation to imply no retorts.
• Consciously does not exhaust dunder with the idea that it benefits re-use.
• Cleans dunder and skimmings cisterns every other week.

1825, Robert Hibbert. Hints to the Young Jamaica Sugar Planter.

• Before the era of retorts and we see a two still system.
• Mentions what the book keeper records.
• Acknowledges use of “tainted cane juice” i.e. rum canes.
• Mentions the corrective of suspending a basket of broken lime stones. [This turns out to be a Bryan Higgins idea from 25 years prior.]
• Mentions using 2000 gallon still but prefers broad shallow 500 gallon pot still.
• Describes something like a still parrot (that usually floats a hydrometer) to decant aroma-negative oils from the distillate.
• Mentions forms printed of goings on at estates that are mailed to proprietors in England.

1825, Rum – History, 1825-1946 : Ephemera; Printed Book 1825-1986

• Held at the Hagley Library in Wilmington, DE.
• Digitized through the Adams Morgan digital library collection.
• Collected during Seagram’s tenure as the owner of Long Pond.
• Likely holds value but I’m really not sure what is in it.

1830, George Richardson Porter. The nature and properties of the sugar cane. Chap. VIII; On the distillation of rum, 93-102.

• Mentions using a two copper still system of 1000 & 600 gallons with pewter worms.
• Mentions a dunder cistern, skimmings cistern, and as many as 10-12 fermenting vats.
• Notes dunder is sometimes saved by one crop to another, but does not agree with the practice.
• Mentions Winward island advice of skimmings, dunder and water mixed and fermenting for 24 hours before molasses is added at 3% scaling and then another 3% after a few more days.
• Shows a comparison of Jamaican washes differing from other islands being more dunder heavy with less molasses and more skimmings; ultimately containing less sweets.
• Quotes Edward’s West Indies and concurs that dunder may improve yield but injurs the flavour and quality.
• Proposes closed fermentation with an air lock to prevent alcohol from escaping with CO2.
• Very aware of a correlation between fermentation temperature and quality.
• Mentions use of alkalines and Dr. Higgins proposed use of a basket of lime stone suspended in the wash.
• Cleans cisterns with lime water every time they are used.
• Provides data on average returns of an operation in Grenada, noting how it varies with the seasonal quality of cane juice.

1831, John Bell. practical treatise on the culture of sugar cane and distillation of rum.

• Currently a lost text but it is held by Columbia University who offers a digitization service for rare books (my estimate $85).
• Referenced by U.S. government chemist H.W. Wiley as containing unique information on feculancies.
• May describe early use of the dirty cistern.
• Mentions a dunder/lees cistern that is 4 times larger than a fermenter.

1843, W.F. Whitehouse. Agricola’s Letters and Essays on Sugar-Farming in Jamaica (truncated and annotated).

• Major reflection on production that inspired many others to compete for writing prize winning essays on rum and other cane related subjects.
• Describes common clean process.
• Early accurate description of the value of dunder.
• Describes common clean process and makes no mention of flavoured rum.
• Features distill-off between Whitehouse and a European distiller who is selling a patent technology of pitched cultured yeast as opposed to spontaneous fermentation.
• Describes the moral priority of sugar production over rum.
• Launches a lot of ships and later reflected upon by Wray:

Thus a spirit was implanted—a curiosity engendered, which cannot fail to develop itself to the benefit of “the planting interest”.

1843, John Biggs. Observations on the manufacture of sugar and rum in Jamaica.

• References Wedderburn name as associated with the Retreat and Prospect estates.
• Trained as a civil engineer and for the most part his contributions to rum were helping along adoption of steam heated stills to reduce off aroma and create a more regular boiling.

[There are interviews with John and Andrew Wedderburn from 1831 which discuss production economics. The English realize that molasses alone cannot produce rum and they cannot simply import all the molasses from Jamaica and produce the rum themselves because the product will not be worthy of being called rum. There is also an interview with the spirits chemist Dr. Ure (referenced next by Wray regarding the essential oil from cellular tissue decomposition) who makes possibly the earliest acknowledgement of rum oil I have ever come across.]

1844, Leonard Wray. The Sugar Planter’s Companion.

• Written for India and very different from his later text.
• Contains more ideas on flavoured rum as opposed to his 1948 text which may have been tempered by the global commercial crisis.
• Describes vats for spontaneous fermentation being “in season” or “out of season” and methods of remedy at the start of the crop.
• Describes the original pine-apple rum which saw co-fermentation of merely the skins. Recommends putting cane rinds in all ferments.
• Opines of finer rums being taken at lower proofs. Cuts personal estate rum with water boiled with avocado leaf.

1847, John McCullock. Observations on the Manufacture of Rum.

• Starts by hyping skimmings and explaining how they create flavor.
• Spends 2/3 of the 15 page text on atomic and molecular theory of sugar fermentation.
• Believes the peculiar flavour of rum is caused by skimmings and not by dunder which can contribute an offensive odor which he notes goes away.
• Discredits superstition that vats must be re-filled quickly before they get cold. Cleans vats with boiling water and covers them with powdered lime.
• Recommends adding fresh yeast if the wort becomes languid and mentions: “This may startle the West India distillers a little”.
• Adds soap to prevent wort boiling over in the still.
• Publishes another book in 1867 called, Distillation, Brewing, and Malting (no mention of rum) which is quite often lucid (if not mildly insane) and shows a British distillers take on distilling in America. There is a notable description of a charge chambered still.

1848, Leonard Wray Esq. Practical Sugar Planter.

• Describes common clean process in a less aroma-centric way than his 1844 text.
• Does not use a mixing cistern.
• Does not mention flavoured rum.
• Significantly plagiarized by F.A. Bell in 1866 who published a text in Australia.
• Describes odd negative aroma in rum of unique persistence that may be TDN or TNN and makes up the negative form of the hogo concept (as opposed to damascenone). I believe it is possibly produced by brettanomyces at high pH. Another possibility for the negative aroma that challenged many distillers could be organic bases freed by trying to operate at too high a pH.

1848, Three Essays on the Cultivation of the Sugar-Cane in Trinidad.

• Focused on growing cane with unique notes on preferences for rum quality.
• “the Javanese or Guinea cane is easily distinguished by its violet colour; it thrives best in light soils, and though watery, and consequently yielding but a small proportion of sugar, it is preferred in the distillation of rum:”
• “Battavia cane which we observe sometimes in our fields, and is known by its striped violet colour and its short joints, is grown in the East Indies, and in Jamaica are to be seen entire fields of it, where it is cultivated on account of its producing good rum, for which purpose it is preferable to all the other kinds of cane.”
• [Regarding Jamaica] “There are also the ribbon and purple canes, which seem to resemble the Mont Blanc; but as producing less sugar, are probably cultivated with a view to improve the quality of rum.”

1855, A. Coulon. Le fabricant de rhum à la Martinique. Paris

• Lost French text referenced by Kervegant that likely describes production methods adjacent to early Jamaican rums.
• Before the Mount Pelée eruption of 1902 that destroyed St. Pierre, many of the ferments of Martinique supposedly resembled Jamaica.
• Another bibliography claims this was published in 1886.

1855, Dr. Wilton Turner. Directions for the Manufacture of Rum.

• From an 1896 copy republished after his death, so I assumed it would be his last year.
• Introduces sulphuric acid to rum making in the West Indies starting with Guyana.
• Patents a process and licenses it to estates in Guyana
• Pronounces “lime and alkalies are our enemies, acids our friends and assistants.” ending the lime obsessed era started by Bryan Higgins at the beginning of the century.
• Practices spontaneous fermentation.
• Followed in the 1896 publication by another unnamed author who managed the patent.
• A pamphlet about sulphuric acid use was privately printed and disseminated around Guyana in the 1850’s or 1860’s.
• Acknowledges that the sulphuric acid idea was borrowed from sugar-beet fermentation in Europe.

1866, F.A. Bell. Handbook of practical directions for sugar cane planting, sugar making and the distillation of rum.

• Published in Sydney, Australia
• Completely plagiarized from Leonard Wray.
• Describes personal anecdote of being in Jamaica in 1841 and purchasing some original 5 year old Wedderburn and pronouncing it quite expensive but glorious.
• Mentions that Australians don’t know what rum can taste like, having not experienced Jamaica rum.

1871, J.S. Manufacture of Sugar and Rum.

• Published in The Sugar Cane possibly as a direct contrast to the article by Patrick Neilson.
• Believes in the moral superiority of sugar production which is a recurring tension in Jamaica.
• Practices common clean process and pursues efficiency.
• Acknowledges “experimentalists”.
• Uses the term “morbose process” which may signal awareness of a switch from high pH ferments propped up by lime and high acid ferments featuring sour skimmings.

1871, Patrick Neilson. Jamaica. Manufacture of Sugar and Rum.

• No estate is acknowledged but the author is from Trelawny by way of Scotland.
• Promotes slow fermentation like many authors before him.
• Builds the terroir mythology of unique soils contributing to flavor.
• Describes the dirty cistern which may match the mud vat of other authors which were precursors to the muck hole and various other acid generating cisterns described by Charlies Allan.
• Possibly responsible for a change from a lime obsessed common clean process to a high acid style of rum.
• Converts 2/3 of his vats from common clean process to a process that mimics the dirty cistern.
• Possibly uses common clean washes to draw down the low wines accumulated from distilling heavier washes.
• Infinitely quotable and worth careful study.
• Likely origins of the Hampden process before it becomes testing ground of the Experiment Station decades later.

1873, Sugar Farm in Jamaica

• This is possibly a journal/manuscript and may be in cursive.
• May also be related to “The Penny Magazine, pp348-349”
• Penny magazine article may simply be a reproduction of a single day, Sept. 3rd.
• Not completely clear what it is or isn’t…

1875, R.H. Burton. The Distillation of Rum.

• 50 page article serialized in The Sugar Cane.
• Author is working and resides in Puerto Rico, but has extensive experience in Jamaica and across the region.
• Writes the article while on a layover in Jamaica resolving a patent dispute for a process featuring sulphited cane.
• Multiple anecdotes about raw beef in rum well before the Guyana rum scandal of the end of the century.
• Describes the process of a master distiller who may be Jamaican born and the equivalent of Uncle Nearest.
• Describes Old Jamaica and how many of the early highly regarded rums may not have been economically viable.
• Describes the operation of the mud vat, a precursor to the muck hole.
• Extensively mentions the economics of rum production and describes many ferments that may have accepted ABV’s lower than 5%.
• Finer points and anecdotes galore!
• Well worth careful study from both a production and marketing stand point.

1882. Anonymous. Manufacture of Rum by a Jamaica distiller.

• Published in Guyana in the text The Overseer’s Manual. Also published in The Sugar Cane.
• Recently referenced in The Oxford Companion to Spirits and Cocktails, page 606 (and not by me!).
• Referenced by Percival Greg in 1895 in his paper titled The Jamaica Yeasts.
• Contributes to the terroir mythology where many have failed with the method presented while others have succeeded “without any apparent effort”.
• Features such gems as throw nothing away.
• Describes a mixing cistern filled with sugar cane bagasse from rum canes.
• Likely describes the production of the Vale Royal Wedderburn.
• Acknowledges the idea of having to scrap things and start again if the ferment become acetous.
• Appears to describe a top fermenting fission yeast which attracted the eye of Percival Greg.

1889, Samuel Stricker. Manufacture of Rum, Jamaica.

• Describes common clean process.
• Concerned with the inversion of sucrose effecting fermentation.
• Frequent mentions of albumin from skimmings.
• Frequent mentions of Pasteur.
• Mention of the fermentation fault everlasting seed.
• Mentions admiration of Demerara process then ties albumen used in Jamaica to ester development.
• Presents unique ideas on how dunder should be prepared for re-use such as driving off volatile acids and then liming.
• Bastard cedar and okra are introduced as ways to increase albumen.
• Numerous descriptions of visual queues and how to interpret them.
• Mentions observations where everything should be cleaned and restarted.
• Mentions flavoured rum but chooses not to comment.

1893, Percival Greg. Fermentation in Rum Distilleries.

• Presents new ideas in fermentation by both Pasteur and Hansen
• Outlines basics of producing Jamaica rum (almost like he has little experience).
• Mentions old timers opinion that really aromatic rum can only be produced by ripe old dunder.
• Mentions a present day anecdote of a distiller throwing away sour dunder.
• Mentions problems of distillers matching supplies of raw materials. Stored molasses goes sour.
• Mentions nutritive benefits of dunder for yeast, but also bacteria (which was considered undesirable).
• States: “Therefore, spontaneous fermentation must be done away with.”
• Recommends “selection and cultivation of a suitable type of yeast” that takes into account aroma and attenuation.
• Mentions many Saccharomyces yeast, but does not yet mention a fission yeast.

1895, Edward Davson, Notebook belonging to Edward Davson c.1895 with
Rum recipe and other manufacturing comments.

• I requested this from the West India Committee, but no one seems to actively manage their library at the moment.
• Davson was president of the West India Committee and active through the 1920’s.

1895, Percival Greg. Rum Analysis.

• Mentions competition between German producers trying to make a rum from beet sugar.
• Shares data from German scientist, Eugene Sell’s book on spirit analysis.
• Describes significance of esters at a chemical level not yet obsessed over.
• Tries to differentiate “cheap” and “expensive rums chemically.
• Describes an experiment with isolated rum oil where he artificially increases the amount and then sends it to a dealer for price appraisal.

1895, Percival Greg. Notes on Prof. Jorgensens’s “Micro-organism of fermentation.”

• Contemplates pure yeast fermentation.
• Essentially recommends Jamaica upgrade their ideas on production.

1895, Percival Greg. A Contribution to the Study of the Production of the Aroma in Rum (Part 1).

• Describes working with a top fermenting yeast No. 18 that produces desirable aroma.
• Performs experiment to prove desirable aroma must come from molasses plus dunder.
• Isolates production of the aroma to treatment with lime that probably creates a high pH.
• Concludes production of desired aroma is multi-factorial.

1895, Percival Greg. The Jamaica Yeasts.

• References 1882. Anonymous. Manufacture of Rum by a Jamaica distiller, but with completely wrong citation details.
• Believes that his observations with yeast No. 18 parallel the “rum fat” observations at Vale Royal.
• Suspects that distilleries having trouble producing German rum may not have the correct yeast.
• Lists the various fermentation times and attenuations of yeasts in his collection.
• Data implies lower frequency of occurrence of top fermenting yeast.
• Provides prices for yeast growing apparatuses of German designs.

1895, Percival Greg. A Contribution to the Study of the Production of the Aroma in Rum (Part 2).

• Provides sensory descriptions of the “fruit ether” he isolates.
• Isolates the fruit aroma from dunder that had an acetic ferment with petroleum ether as a solvent. Performs basic analysis with caustic soda and sulfuric acid.
• Performs dunder experiments that reveal how aroma is bound up in lime as salts and can be harnessed by planned release later (Arroyo explored this territory).
• Hypothesizes that some “fruit acid” is bound in the wax.
• Posits that the “common or clean” process loses aroma if it is run too soon because no non-volatile acid can liberate the higher value volatile-acid.
• Posits that using acid skimmings by running them over a “dirty cistern” filled with cane trash will liberate aroma bound as salts if sufficient heating with lime is given to the cane juice in the boiling house. He doesn’t yet seem to realize a wash high in acetic acid will help select for a fission yeast.
• Posits that a trash cistern should be managed to contain an amount of ethanol so that when an acid is liberated it will be more likely to form an ester than to remain in the free state.
• Posits that late stage acetic souring from extended resting of ferments may be beneficial to freeing the aroma. Ties the phenomenon to the visual queue of a “creamy head” that he has examined to be largely acetic acid bacteria.
• Describes a double trash cistern system where skimmings are given 24 hours of souring.
• Soured skimmings are not back slopped because new alkaline skimmings would then lockup and spoil the progress of soured skimmings in releasing their aroma.
• Ponders how terroir and cane varietal drive the fruit acids he is trying to liberate.
• Ponders the formation of “new leather” aroma in rum, but wonders if it may be an adulteration. Greg may be operating at the intersection of maximizing ester formation and producing radiant damascenone—rum oil.

1896, Percival Greg. A Contribution to the Study of the Production of the Aroma in Rum (Part 3).

• Posits that the fruit acid described in part 2 is an oxidation product.
• Posits lime helps set free the “essential oil of rum”.
• Performs experiment with cane juices boiled with lime and aroma extracted by chloroform.
• Likely encounters damascenone; “an aroma which is so utterly different to that of any other spirits”.
• Observes that rum oil in cane juice is not removed by filtration and does not form any obvious insoluble layer above or below the juice.
• Observes palmitic acid layer floating in cane juice and attributes it to coming from cane wax.
• Posits that much rum oil is lost to evaporation due to how cane juice is processed.
• Observes high boiling point of rum oil and how it comes across in the later runnings of the still.
• Isolates rum oil from dunder and to a lesser degree from molasses.
• Posits that a retort full of treated cane juice may produce rum oil, but then cryptically describes a comparable process used elsewhere that uses table salt instead of lime (This reminds me of a Joseph Merory idea proposed for fruit wines).
• Posits that like fruit acids, the terroir idea also applies to rum oil.
• Observes alkaline bases of the pyridene group set free by over liming that smell like “the dark brown liquid which may be found in the stem of a foul tobacco pipe”. My bet is this may be a common fault in earlier rums and often attributed to an “empyreumatic oil”.
• Posits that free bases may be bad for fermentation, but he may just be observing a pH that is not hospitable.
• Describes analysis phenomenon where free bases effect litmust but have no bearing on phenol-phthalein (I have no experience with this)
• Calls the terroir effect only “potential, not actual; that is is latent, dormant, and only brought into existence during the process of manufacture”.

1896, Percival Greg. “Selected” Yeasts and General Considerations.

• Promotes the success of Hansen’s system.
• Recommends trials to make sure a particular yeast is best adapted to a substrate so that it stays dominant.
• Presents basic ideas of scaling up starters and overcoming wild yeasts used by the wine industry.
• Returns to mention the trash cistern of creating acid skimmings tying it to flavoured rum.
• Mentions that trash cistern may be relied upon to produce yeast.
• Mentions the idea of feeding the trash cistern with molasses and dunder but then that no high priced rums are produced that way.
• Makes comparison to the sour mash Bourbon process.

1903, J. Steele. Report On Excise Restrictions.

• Steam is sometimes used to heat stills, but direct fire is more common.
• Notes that few pumps are used (many are described in earlier documents).
• H.H. Cousins proposes to Steele of hiring a fermentation chemist for Jamaica to improve the quality of rum.
• Posits the idea that if a cultivated yeast is used and something like skimmings are removed from the wort, the product may not longer be Jamaican rum.
• Mentions the distillers are not knowledgeable of scientific brewing. Proposes investigating the source of rum flavour.
• Mentions German rum is fitfully produced and not consecutively.
• Surprised that wealthy makers of German rum have not investigated the science themselves and opines that it may not be fair for the public to subsidize research that possibly benefits so few.

1906, Charles Allen. Reports of the Jamaica Sugar Experiment Station.

• Experiment station distillery used 110 gallon puncheons as fermenters and a 60 gallon double retort pot still.
• They most often did not use skimmings but only have raw cane juice which they believe makes their rum lighter than export quality.
• Provides an explanation of Arnaboldi scale which is in pounds per barrel at 80°F similar to brewers scales at the time. Provides a conversion table that may be useful for older literature.
• Data is provided for numerous basic fermentations that often saw weak yeasts and too much bacteria.
• On experiment 12 they finally get a spontaneous fission yeast ferment and significant acidity in the wash improving the rum, but also giving them a poor yield.
• Experiments start with fresh cane juice to explore Appleton’s process at the time. This implies fresh cane juice, dunder, and molasses.
• Notes that the gravity of fresh cane could be very misleading when compared to the fermentable sugar content.
• They perform fermentation tests with sour skimmings and look at theoretical yields.
• They experiment with their own dunder as well as dunder take from Mesopotamia in Westmoreland (supplied by Percival Greg).
• Greg’s dunder had 23.5 g/L of acidity! (I think as sulfuric), but the ester content of the resulting rums was nothing special.
• Allan visits Cinnamon Hill in St. James and then Denbigh in Clarendon to learn common clean production before visiting Cambridge estate in Trelawny to learn the flavoured rum process. He also visits other estates in Westmoreland, St. Catherine and St. Ann.
• Faces challenge of differentiating common clean and flavoured rum. All estates with one exception making flavoured rum were northside and ratooning estates. Most think the flavour of the rums is from the esential oil of the cane.
• Allan believes both the round about process of flavoured rum is unnecessary and that the essential oil idea is incorrect.
• Ester numbers are anonymously supplied by parish for possibly the entire island.
• Common Clean process in general is dunder, molasses, and skimmings mixed in proportions consistent with the experience of the distiller. Exceptions to the simple formula allow skimmings to stand and sour while others use a trash cistern to speed up souring. Both aim to produce acid.
• Flavoured rum is skimmings, dunder, molasses, acid, and flavour.
• Acid is made from rum canes warmed in the coppers (possibly not limed?). Dunder and some skimmings are added and after fermentation this is pumped on to cane trash in cisterns to get sour. Wash bottoms are added to these cisterns from time to time.
• Flavour is prepared by adding rum cane juice into outside cisterns with trash and dunder stored from the former crop. Liquid from the “muck hole” is added to this cistern. The muck hole is thicker parts of dunder, lees from the retorts, and more cane trash. Flavour is then moved and added to subsequent cisterns of trash with wash bottoms.
• Even more details are presented.
• Lots of analytic numbers are presented for both components of Common Clean and Flavoured rums. (There is less volatile acid in the acid than you’d think.)
• Data from “West End medium rums” are presented.
• Component data from “North side medium rums” are presented, but with holes in data points…
• Allan notes “acetic acid is produced by other classes of bacteria”.
• Mentions butyric acid bacteria has been isolated from much distilling material, but particularly the muck hole.
• Allan describes the flavoured rum producers techniques as crude and they possibly did not add lime during flavour production until he came around.
• Allan calls the yeast schizosaccharomyces pombe “more a huge bacterium than a yeast.”
• Allan mentions waste of material as important to flavour “should form one of the strongest arguments why inferior rum made by a less expensive process should be debarred from being sold as a Jamaica rum.”

1906, H.H. Cousins. Confidential: Instruction For Making High-Ether Rum.

• Calls out certain producers in his description of what the island produces.
• Mentions Jamaica having a monopoly on ethers in the world’s supply of rum.
• Proposes legal levels of esters in the U.S. and U.K. then plans to achieve them by increasing vat space for longer fermentations and averaging up deficient productions with high ester rum produced in few distilleries for cooperative use by others.
• Provides anecdotes that ester level is not the sole predictor of value for a mark.
• Informally correlates a 1% acidity common clean wash to 200 esters and a 3% acidity Trelawny wash to 1000 esters.
• Mentions that an increase in only ethyl-acetate but not supported by an increase in other esters will not add value.
• Mentions the trade dictum “rums are not sold on Ethers.”
• Claims the common clean process got ethyl acetate by the “spontaneous acidification of the wash”
• Differentiates Westmoreland rums where skimmings simply sour from “flavoured rums” where various cistern are kept going.
• Proposes the use of the quick vinegar process for flavoured rums.
• Mentions the German “stalky” descriptor if rums have ethyl acetate and fruit ester but no butyric ester.
• Mentions Butyric acid produced in dunder that forms a head to keep out oxygen. Believes that it may be beneficial to create butyric acid in a separate process.
• Describes an engineered butyric ferment started with surface soil.
• In ordinary rums, butyric acid is controlled by normal bacterial changes but in flavoured rum it is engineered.
• Mentions the quality of Hampden, Ettingeton and Cave Valley rums.
• Never mentions Plummer or Wedderburn, but again mentions “Westmoreland mark rum” and “German flavoured rum”.
• Mentions that generally speaking, 1/4 of the fermentable matter in German rum is turned into acids. 2/3 is non-volatile acid and only 1/40 of the acid is recovered and sold in rum.
• Presents an easy to follow system that to some degree looks like cheating.

1906, Charles Allan. Lectures on Fermentation In Relation to Jamaica Rum.

• Allan starts with an introduction to fermentation and provides an expansive view beyond just ethanol production.
• Provides statistic breakdown to show how many more congeners are in heavy rum used for blending.
• Mentions the age old wisdom that the distiller should know which type of rum they wish to make before they start. Opines you must understand the processes of flavoured rum or you will suffer a serious loss in production.
• Provides a breakdown of all the congener classes as they were understood at the time.
• Mentions the value of esters but presents the idea of substances of which little is known “but of powerful aromatic flavour” (very likely damascenone).
• Tells anecdotes of the problems of tying value to ester numbers.
• **** Incomplete?

1907, H.H. Cousins. Jamaica Rum.

• Mentions (with a sort of wit) that Jamaica has trade secrets, and that rum is a “jealous and unapproachable” business.
• Not afraid of competition and believes that the “slow minutiae of a high flavoured rum process” could never be part of a large sugar factory such as in Cuba or Guyana.
• Acknowledges three types of Jamaica rum; local, home, and continental. Sees future danger in under production rather than over production.
• Everything in Jamaica is blended and you probably cannot find a choice mature mark anymore.
• Describes abandonment of idea to ban export of rums with less than 200 esters because of prejudice of high quality of rums at the 100+ ester level.
• Describes syndicate formed to monopolize the sale of Jamaica rum and raise the price. Makes comparison to retail investment in Guinness beer.
• Best rums in the home trade are Westmoreland followed by Clarendon, St. James, and Trelawney. Characterized by slow fermentation with sour skimmings in ground cisterns.
• Cousins notes: “These acids are not producible from sugars” which is sort of an open secret in Jamaica rum and why you cannot make heavy rum from molasses alone (until Arroyo).
• Quotes a broker presenting him with marks that are standards of quality: “We do not want ethers, but a round rummy spirit” Cousins notes that all the chosen marks were also high in ethers…
• Mentions buyers hated: cloudiness on dilution, a burnt flavor, and excessive obscuration.
• Credits importer Finke & Co. with northside planters for creating continental rum style. Development may have saved the small northside planters.
• Mentions fission yeasts as chief yeast of continental rums. Goes onto describing erratic nature of production.

1907, S.F Ashby. Reports of the Jamaica Sugar Experiment Station.

• Presents numbers as benchmarks for returns on common clean rums
• Presents experiments by participants of the course for distillers. Last names are given of attendants.
• Experiment 1 explores higher quality flavour by gradual additions to the liquor of prepared materials. They start with fresh cane juice then add dunder, then add molasses, then add acid, all in intervals.
• Experiment 2 explores high setting and muddy dunder on the common clean process. Also features gradual additions of material ending with acid. Distillate also features high ether treatment. Return is bad, but the rum is good.
• Experiment 3 is an ordinary setting and process; all in the pot with no incremental additions.
• Experiment 4 was a reduced dunder experiment.
• Experiment 5 was an ordinary process with a medium settings.
• Experiment 6 was a ordinary process with high setting and a little flavour added; sugar too high for economic production.
• Experiment 7 was an ordinary process but high ether treatment for distillate; result “tea-rum” character.
• Experiment 8 was a common clean type with a unique schedule of additions.
• Presents new series of experiments but also add evaporated cane juice to the list of materials. They present data for their ferments and we see esters that don’t go above 100 on average.
• Ashby presents a report on the study of fermentation in the manufacture of rum which was published in multiple places.
• Ashby summarizes the contributions of Percival Greg and his work with fission yeasts. Mentions Greg promoted the importance of yeasts while Allan demoted them and promoted bacteria, making it his focus. Ashby chooses yeast as a starting point.
• Performs basic experiments on acid tolerance of budding and fission yeasts.
• Performs basic experiments on multiple fission yeasts and notes characteristics of top and bottom fermenters.
• Distills results with a glass laboratory still and finds no characteristic aroma for all yeasts; (Likely out of pH range).
• Mentions distiller’s experience “as they consider that a wash showing a strong fatty head due to the top fermenting fission yeast yields the best flavoured rum”.
• Performs experiments on maximum alcohol yields by fission yeasts.
• Performs experiments on washes of different gravity with fission yeasts. Dunder represents 3/5 the gravity. Dunder was a light cane juice product and more than usual had to be used to contribute a normal acidity.
• Performs comparative experiments on yeast growth (which is important because cell division and growth creates aroma).
• Makes the observation that top fermenting fission yeasts have a tendency to switch to bottom and vice versa.
• Performs experiments on the “fruit ether” yeast which may be a film yeast. The yeast is assumed to produce both alcohol and acetic acid and then ultimately high levels of ethyl acetate as a biotransformation.
• Performs experiments with acetic acid producing bacteria.
• Includes “Lectures on Fermentation In Relation to Jamaica Rum.” by Charles Allan but I will treat it as its own document above at 1906.
• Notes page 154 that retorts on flavored estates can be as high as 7% acidity.

1908, S.F Ashby. Reports of the Jamaica Sugar Experiment Station.

• ***Ran out of time to review.

1908 H.H. Cousins. COPY OF A MEMORANDUM.

• Rebukes comments made by E.A. Pairault about Jamaica rum that appeared in the Royal Commission on Whiskey and other Potable Spirits.
• Itemizes a rebuttal and disavows any adulterations such as leather, tobacco, or iris.
• Mentions the importance of ester forming yeast in the Jamaica process.
• Pages in Pairault not remarked upon by H.H. Cousins mention that in 1901 Pairault send back wash samples to Pasteur’s labs for yeast isolation.

1909, S.F. Ashby. Yeast in Jamaica Rum Distilleries.

• Starts by noting that forty distillers have attended the three week course for distillers on fermentation in the last four years.
• Tells anecdote of putting brewing yeast in wine and vice versa then the necessity of congruence.
• Mentions that most yeast are stressed by Jamaican wash conditions, but Jamaica has found a yeast that can tolerate its conditions; schizosaccharomyces pombe.
• Notes it is a mystery of how fission yeasts get into the distillery.
• Presents the idea of cultivating two types of fission yeasts (top and bottom fermenting) and sending them out to the estates to start crop. Notes that many distilleries have applied for them.
• Presents photos of fission yeasts at 350X magnification.
• Stresses that these yeast alone do not produce flavour in rum.
• Describes another budding yeast that can produce significant amounts of ethyl acetate that may be of value.
• Describes another budding yeast that can ferment very high gravity washes but is a cause of foaming.

1909, S.F. Ashby. The Study of Fermentations in the Manufacture of Jamaica Rum.

• A republished excerpt from the report of the Jamaica Sugar Experiment Station, 1907

1913. S.F. Ashby. Report on the Inspection of Certain Rum Distilleries in St. James, Westmoreland and Trelawny.

• Visits a Westmoreland distillery at the request of the owner and immediately describes cane juice being run into a cistern of coarse and fine cane trash that resembles the description from Vale Royal. Notices souring but little yeast fermentation.
• This distillery imported molasses so no longer used skimmings but did use their own fresh cane.
• Defective coil on still effecting returns.
• Sometimes they are using hot materials which effect the start of fermentation.
• Some washes threw up yellowish-brown heads composed of mainly fission yeasts that lasted 4-5 days then were covered with mycoderma.
• Observes patterns between ferments dominated by budding or fission yeasts.
• Notes the factors promoting dominant fission yeast fermentation had not been sufficiently worked out.
• Second distillery uses “skimmings of normal thick consistency” and fermentation rapidly sets in.
• Observes again, a mix of fission and budding yeast dominance in vats next to each other.
• Third distillery no longer makes sugar, grinds cane, and possibly has skimmings. Ashby asks them to clean the skimmings vats with lime and formalin. Possibly these are former space for skimmings that now only holds cane juice?
• Ferments feature some fission yeast but are overrun by budding yeast; juice thought under tempered.
• Distillery was short on dunder and was using water which may have contributed problems.
• Ashby sends for fresh fission yeasts from Hope to strengthen the fermentation.
• Notes the distillery has inadequate space to cool skimmings before mixing.

1944-1958, Misc. Jamaica Association of Sugar Technologists (J.A.S.T.).

• Journal quarterly that shows off the technical discussion of producers.
• In the 1940’s, we see that Jamaica lost control of fission yeasts and tried to contact Rafael Arroyo about microbiology consulting for the island through an intermediary.
• Research into Jamaica processes is proposed but never materializes.
• McFarlane presents a unique paper in 1946 describing the math of ester chemistry and acknowledging rum oil. He presents an extensive bibliography.
• McFarlane presents another paper in 1948 that looks at new trends in fermentation and mentions Arroyo extensively, showing a bibliography that collected the majority of Arroyo’s work.
• Numerous papers on dunder disposal show them being as creative as putting it in sinkholes.
• In 1958, a history of the Rum Pool is presented which for every year, explains consolidation, shows who produced what, and tells how much continental rum was produced.