The Alchemical testament of John Gibbs of Exeter, and other 16th century English alchemists


This is a peculiar little text, apparently from the 16th century. The original MS is apparently Ashmole 1423 in the Bodleian library, yet I can’t find it in their catalogue, it seems because it isnt properly digitised yet and they have multiple catalogues. Mind you I wonder maybe it doesn’t exist and the attribution is wrong.…

The Alchemy website has a listing of all works within the book, and it seems to date from the end of the 16th century.

It’s yet another book whose individual importance is low but as one of many such books around at the time can give a much broader and informed picture of the state of knowledge and public interest in alchemy, chymistry and related topics at the time. The more I have learnt the more I have realised that the public histories of alchemy give a very simple idea of it, necessarily so in many cases, but in others I think the research hasn’t been done, especially amongst all the surviving manuscripts.

So of course it probably won’t get digitised, he typed cynically.

Anyway, the 19th century transcription can be found here online:

It starts very seriously, introducing John Gybbys of Exeter, who on his deathbed, wants to communicate his ‘great secret’ he has. He does so “ and ye wyll, shall have a cause to pray for my sowle and for the good deyd ye may do be my informacyn.” which to me sounds rather Catholic, i.e. pre-reformation. In the notes accompanying the transcription, the MS apparently belonged to John Dee in 1563.

There follows an odd text, clearly somewhat cut and pasted in from other sources, which starts with instructions to melt lead and hold a stick in it when it cools, so as to leave a hole. Then take mercury, “true and good; see he be strained and clarified well through a piece of leather white…” (modernised spellings)

This mercury is to be put to the metal, seemingly into the hole you have, whilst it is still hot even if solid, and a cucurbit of glass luted above the hole, over the crucible, and anything that appears in it is collected.

Eventually, you proceed to the usual gentle heating of your hermetically sealed vessel, which isn’t usually as well described as here. The mercury spirit that is distilled from it all is put back to the body, “… and iff the body reseave the spyritt againe, itt is perfytte, iff he wyll, not prove hym again.”

The stone you get is called lapis adamantis, or in English a ‘Shypman stone’ or a ‘lood stone’.

That is certainly a good way to confuse names.

The second step is to take the stone, put it in a glass pot, and mortified mercury, lute it shut, heat it, on and off, for 40 days! Which should cause the mercury to dissolve into a crystall clear water.

After for 24 hours burning with a great fire, it will turn black, when it should be taken out the pot. This is rather a departure from the norm. Black is supposed to change to white, and then red, often via a rainbow colour step.

I can fantasise about a poorly educated, country based alchemist gulling less sophisticated people, but it isn’t even clear if Gybbys really existed and was an alchemist!

When added to liquid mercury it will mortify it and it will harden, often shaking the crucible as it does so. When heated it will all melt and dissolve again, and it can be cast into an ingot.

An ingot of what, I hear you ask. To which I can only say, this sounds like a method of making a silver analogue. Not gold. Of course, Saturn usually means lead, the trick is how to make the lead harder and shinier.

Note the way it combines common forms of language and action yet in a slightly different way from normal. I’m sure that as historians dig deeper into the many different manuscripts, they will find many such variations, due to the many different people that have written them.

Here’s a photo of a somewhat weathered lead cauldron casting at Kentwell, done maybe 20 years ago now:


Note the colour and dullness, which has to be overcome in order to make it look like silver.

As for other alchemists, every now and then I stumble across mention of others, there really were quite a lot of them. For instance, in “Alchemical poetry 1575- 1700” (the title is a lie, there is earlier stuff in it in translation) there is a work by Edward Cradock.

He attended Oxford University, and lived from around 1536- 1594, i.e. through the various religious upheavals and political change. He was a doctor of theology at Oxford and lectured on the topic, and according to a bibliographical entry on him, spent a lot of time on alchemy. He produced 3 alchemical works, the third being a poem “A treatise touching the Philosopher’s stone” which is therefore in the book above.

The book also features two verse works by Simon forman, and three verse translations from middle french by William Backhouses, in 1644. The texts are from 1413 and 1500, the latter being by pseudo- Jean de meun and titled “The complaint of Nature against the Erronious Alchymist” and ”The Alchymyst’s Answere to Nature”

I find it interesting that someone would translated older French alchemical poetry into English in the mid-17th century, and think it’s all part of the broader cultural importance of alchemy, which is something I just don’t think has been adequately covered, especially in a more public friendly fashion. It’s easy enough to state that alchemy was widely known of and popular amongst learned people, much harder to explain it in both breadth and depth.


The complicated braid of alchemical thought and practise


A few years ago now, when I got into alchemy, the more I read, the more confused I got. At first it seemed fairly simple, but after a few years I managed to find more sources and information and it all got very complicated. After a few more years, with more thinking, reading and experimenting it made more sense again.

So, the complexity and difficulties I have had were in part due to the different streams, or threads, of alchemical thought. It can be thought of a little like this, showing the start of alchemy:


ime is going down the page, and at the top we have two streams of thought and practise, i.e. philosophy and practical workshop recipes, joining together. At this juncture is a circle with dots in, the dots being people, the individuals who imbibed the knowledge and discussed and wrote and used it. Out of these people came the splits up into schools of alchemy, each with their own approach. 200 or 300 years later, Zosimos, himself a gnostic, is referring to Maria the Jewess and her alchemical school, and there are also works that seem to be from schools of thought related to both of them. Each has it’s own recipes and specific philosophical approach, and favour some terms over others, but they are definitely all alchemy.

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So what did people think about the purity of gold in medieval times?


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Talking with a re-enactment friend about reproduction medieval jewellery, the subject of the purity of gold naturally came up.

This is of course of great interest to moneyers, Kings, alchemists and jewellers. The latter were expected to produce jewellery of a specific purity of gold, and if they did not, they would be fined. In general in medieval Europe, the products of goldsmiths were tested, usually with a touchstone, and a mark stamped upon them to certify this purity. This method is still in use today, except that sometimes the mark is applied with a laser rather than by hand. Hand punching requires a lot of skill, since you are basically hitting a small metal object with a heavy hammer on a narrow headed punch, so there is great potential for distortion in the object.

Anyway, back to the purity levels of gold.

My usual starting place for this sort of thing, “English Medieval Industries” has a lot about the social history part of being a goldsmith, the marks used (including that quite a lot of pieces don’t have a proper set of marks on them at all, which seems odd unless you reckon the law wasn’t followed as well as it should be) and not a lot on the purity.

In one place they do mention that modern gold foil is 23 and a quarter carat with 3/4 of a carat of silver and copper. You can’t make gold foil much less pure than that because the alloy doesn’t beat out flat enough.

However this book was published in 1991, and is well due a new edition.

Another book, “Goldsmiths”, by John Cherry, is from the British museum and has many very nice photographs of objects. It also has a chapter on the product, i.e. gold items. Fortunately the next one on the organisation of the craft includes information that

“In the fifteenth century there was a great change in the standard of gold purity and also in the marking arrangements. Since 1300, the minimum standard for wares of gold had been 19.2 carats. In 1478 it was lowered to 18 carats at which it was to remain until raised in 1576 to 22 carats.”

At this point it should be made clear that a carat was a proportion, with there being 24 carats in total, so 12 carats would be half gold.

The final place to look would of course be works on coinage, since the purity of coins went up and down depending on circumstances, but I don’t have much about that.

Theophilus’ 12th century work “on Divers arts”, instructs in the use of gold a lot, and on method of cementation, but is remarkably quiet, from my skimming through it, about exactly how pure your gold should be. The only exception is with regard to making gold leaf, which requires pure gold. Which you could make using cementation of course.

Certainly people found higher gold alloys to be more valuable, but from memory, most mention of gold in alchemical works specifies “good” gold, whatever that is. There is much more concern with the methods of testing gold and how your alchemically made gold will withstand them. Yet if you consider the false alchemists, the swindlers such as in Chaucer, there must have been some concern with the purity of gold, because some methods do require gold alloys, or make gold alloys, which when treated properly will appear to be pure gold and thus have multiplied the original gold 3 or 4 fold.

From alchemical texts that I have, e.g. the Libellus de Alchimia, chapter 57, “Take of it one part to a hundred parts of any purified and calcined metal, and it will be good for all time.”

The Book of the quintessence, mentions “fine gold”.

John Dastin’s Letter to Pope John XXII mentions “…the most genuine gold…”

Now some authors talk about making pure gold and it being better than normal non-alchemical gold, but that is more a thing of perfection than of the modern ideas of purity.

It seems to be assumed that everyone knows good quality gold and will recognise it. Of course sight alone is not a good indicator of the proportions of metals present.

In Chaucer’s Cannon’s yeoman’s tale, the intent is to make “fine and good” silver, which presumably means pure; there seems a lack of definite medieval information, but nowadays fine silver means 999 parts per thousand, i.e. nearly pure.

From the “Goldsmiths” book we have a number of examples of bad goldsmithing such as the 1441 case in which the Prior of Lewes sent a gilt ship to the Goldsmiths company in London. It was tested and found that 9 of the turrets were stuffed with tin and lead, i.e. not all properly gold. The Lewes goldsmith was noted in the register of the company as making a bad piece.

In 1478 an assayer was appointed to test and mark all gold and silver objects at Goldsmiths’ hall. At this time the standard of gold purity was 18 carats, so obviously they were testing against that standard.

The records of the Goldsmiths’ company in London have examples of how customers were defrauded. They include plating base metal with gold or silver and pretending it was all that metal; rings and buckles made hollow but passed off as solid; false glass stones were used or real ones in copper or latten.

There was also concern with weights in use to weigh gold and silver objects. Obviously, if the weights were wrong, someone would be defrauded. E.g. if you had weights that were slightly too light, you might weigh someone’s gold object as being 3.5 ounces instead of 4, give them money on that basis, then sell it on again as a proper 4 ounce weight object.

So in summary, the purity of gold objects did matter, but obviously being a real industry, goldsmiths in medieval times were concerned with specific percentages of gold. From what I’ve read, the exact composition didn’t matter so much, and the colour of the gold probably varied somewhat from object to object. But all were gold.

Just to show how different colours can be, here’s a piece of 9 carat red gold I have:


It looks not dissimilar to the copper plated coin beside it. Red gold has a lot of copper in it, but of course will be somewhat more corrosion resistant than non-gold alloys. I don’t think medieval people liked this sort of shade much though, because why waste gold in a not very gold coloured item, when it could be in a proper gold coloured item instead?

Testing modern pewter for lead



So, we bought a small pewter flagon for use with my re-enactment group. Second or fourth or tenth hand, it was made in Holland by Daalderop, according to the stamp on the bottom. Apparently a respectable company who had been in business making pewterware since 1880. Nevertheless, I reckoned it was a good idea to test it for lead. The easiest way I could think of to do that was to put some vinegar inside it and see what happened. Just normal kitchen vinegar, nothing special, maybe 2 or 4% acetic acid, at room temperature then a while at 50C in a water bath.

This is the inside before, note some sort of staining corrosion:



And after:

Given the white stains, I have to say this probably does contain some lead, because lead acetate/ carbonate is white, formed by the vinegar reacting with lead and carbon dioxide and suchlike, see page 910 of Partington’s Textbook of Inorganic Chemistry for more information. A lot of countries are less strict about it all than we are here. The company itself has metamorphosed a lot, the 1980’s being lethal to it’s original pewterware business and instead it moved into water heaters! There’s no point therefore in contacting them to check about the metal used.

Identification of a substance by how it looks is of course something done by alchemists, chymists and indeed modern chemists to at least get an idea of what they are dealing with. I remember when I was analysing metals in a laboratory, after a while you could identify the Aluminium alloy by the odd colour highlights it had in it. Mind you that still didn’t stop people sending the wrong bit of alloy to be analysed and us from processing them, thus confusing us when it wouldn’t dissolve in the acids it was supposed to dissolve in. I’d like an analytical instrument or two such as an atomic absorptions spectrometer, but finding 2nd hand ones can be tricky and I don’t have anywhere to put it.

So this flagon will be polished up and set on display, rather than being used, which is a shame.

Update time

So, it turns out that working full time, keeping your re-enactment group going, having a holiday or two, catching up with friends, helping your dad in the garden, practising fighting and hillwalking in order to keep fit, all impact on your ability to actually do blog posts.

Which is annoying.  But then being unemployed is also annoying and tends to mean a lack of money for experiments and books and suchlike.

So I’m afraid I haven’t actually done much in the way of blog post related stuff.  I am of course slowly working on the alchemy book, and it’s shape is improving somewhat, but I need to now find a publisher.

Experiments too are tricky, in that it’s late in the year and there isn’t always enough light or good weather for them.  And I have run out of simple experiments to do.  Complex ones take more than just an afternoon, and often quite a few hours.

Just writing a simple blog post can take a couple of hours of research and writing, after all I don’t like putting up rubbish.

So I’m afraid I shall be adding slowly and not very often to this blog over the winter time, and we shall see how the spring goes.


Making quills for writing with


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For years I have had trouble finding quills for writing with. I’ve asked people about finding them, but some are stupid and think you can magically find good feathers for quills anywhere in the countryside. Of course I have walked a lot in the countryside, and not found any suitable feathers. Except last weekend I might have done. So this post is about trying to prepare them for use as quills.

I expect that as an alchemist you could probably afford to buy ready made quills, until of course you ran out of money, but you would certainly have to be able to sharpen them for use. Who made the quills I haven’t be able to find, perhaps professional scribes produced lots for sale. Anyway, onto the research into how they were prepared.

“Scribes and Illuminators” by Christopher de Hamel is a good place to start. It describes trimming the feathers so that you are just left with the top thicker inches of the main stem. Then you harden it by plunging it into hot sand when damp. This is to harden it and yet make it more flexible. You then need to remove any remaining outer skin and pith within the barrel of it.

You can also find instructions here online:

Cennini, in his “Craftsman’s handbook” of the 15th century, describes how to cut the quill for drawing, and says that goose feathers are best, and emphasises the importance of a sharp penknife.

Unfortunately he doesn’t mention heating it in sand to toughen it.

This all seems far too simple. Unfortunately there isn’t an obvious source of information about how hot the sand should be. Therefore I am reduced to heating a pot with sand in it in the oven.

First, the pot with sand in, fine grained sand:


Pot by Jim (, probably the best historical potter at work in the UK just now.

I used my ordinary kitchen oven, on the grounds that they wouldn’t have had much to play with in heating the pot. The question is why they used a pot with sand in the first place. Probably it was the most controllable way of doing it without exposing the feather to a naked flame.

First attempt with feather 1 was 2 minutes at around 50C, cooling. No apparent difference in the feather.

Next same quill dampened, 80C straight from oven, for 5 minutes. Temp at thermometer reached 82 after 90 seconds, indicating pulse of oven heat still travelling through sand. Also clear that sand acts as a temperature moderator, like with Alchemists and their sand bath, smooths out pulses in heating that might burn things. Thermometer at 85 by end. The tip of the feather was starting to look brown.

Now, feather 2, dampened under tap, at 108C for 5 minutes, dropped to 103 or 104 by end. No clear change in the feather at all really.

So dampened it again and put pot back in oven to 140C. No thermometer this time, it doesn’t go that high, so temperature is approximate. After 5 minutes, quill looks okay, no obvious physical change to it. The outer skin comes off easily as can be seen here:


Higher temperature again – 180C for 7 minutes was enough to cause the quill to go brown. Clearly too hot. Perhaps could be done again with much less time in the sand, but that would be a bit iffy and I don’t have spare feathers.


Now for the cutting test. I use a penknife from Tod’s Stuff (, one of my more expensive early purchases, but worth it. Unfortunately sharpening it is tricky, so it doesn’t cut as well as it should. Most of you will know about cutting pens already, even if you don’t have any skill at it. I don’t have much, it’s a bit fiddly, but I have managed to make usable pens before.

Feather 1 was irritatingly plastic and flexible, and to find decent material I had to cut off nearly a cm of it.

Feather 2 was stronger, and less flexible. The obvious explanation is that the two different feathers, with slightly different diameters of tube and length were of different wall thickness and strength. Obviously I’d need to compare a lot of feathers from specific wing positions to get a scientific answer.

Anyway, feather 2 was generally easier to deal with when cutting it, but I don’t have any ink handy to do a writing test.

So in conclusion, you can probably heat your damp feather to anywhere between 90 and 140 degrees C (but no higher) and get a usable feather out of it. Whether this is precisely what medieval people did, we can’t tell. I also need to test cut a non-treated feather, to see what it feels like. So as usual I end with more questions than answers, but have hopefully narrowed the available possibilities for experiment and helped someone who might do it themselves at some point.





Bile from cattle – an overlooked ingredient in alchemy


Someone I know mentioned the importance of bile, i.e. the fluid produced by your liver and stored in your gall bladder, for digesting food, more specifically fats apparently. It’s some sort of mixture of organic acids and stuff. (I am not a physician or organic chemist)

I recalled that I had read an alchemical recipe that mentioned it, and wondered if the acids in it could help breakdown various organic things in said recipes and perhaps also attack the metals, thus making it all work better.

Therefore I started searching. The first find was of course in the four books of Pseudo-Democritus, also known as The Physika et Mystika. Recipe 10, (on page 91 of Martelli’s translation) says,

“Whiten Cyprian Cadmia as is customary; I mean the cadmia that has been forced out of its ores. Then make it yellow; you shall yellow it with the bile of a calf, or terebinth resin, or castor oil, or egg yolks, which substances can make it yellow. Then lay it on silver; it will be gold by means of the gold and of the ferment [lit. wash/ sauce] of gold. For nature conquers nature.”

So you take most likely oxides of zinc and related stuff that has been burnt, add yellow stuff, and place it on silver and make it gold. I really should try this some time. The difficult question is whether you add heat, or whether this is merely a kind of yellow resinous coating that you give it.

Anyway, I thought that was a good start. Bile was recognised as being yellow and having goldening effects.

I searched further, but couldn’t find mention of bile in Zosimos’ authentic memoirs, or some other texts. About the only mention I could find of it again is in the Stockholm papyrus, where bile is used to make sunstone, along with sulphur and vinegar. How odd, I thought. At least that indicates that it was used in a variety of craftsmen’s recipes of 2k years ago Egypt, since that is where the pseudo-Democritean recipes come from.

But nothing else. Anywhere that I could find. Strangely the notes at the back of Martelli reference a work/ translation of the Leyden papyrus by Halleaux for use of bile, but my English translation doesn’t seem to mention it.

Anyway, I carried on forwards through the centuries, expecting to find some more mentions of it. Nothing in the Book of Crates. Oh, maybe it is mentioned in the Mappae Clavicula, I thought, which is a collection of workshop recipes with a passing similarity to the Leyden and Stockholm papyrus ones. Nope.

The book of the Treasury of Alexander, a book of magic and alchemy which uses various animal fluids, milk, blood and urine. Nope.

In fact looking through what papers, translations and even a scan of a Latin version of De Chemia of Idbn-Umail, and various European works on alchemy, found me only one mention.

That is in the Kitab al-asrar of Rhasis. What is most fun about it is that there seems to be two slightly different versions. One, from an American thesis by Gail Taylor that is a translation of it from the German version done by Ruska, says, on page 281, in The chapter of Animal Matter:

“We have said, in that which has gone before, that there are ten stones, and indeed hair, skull, brain, egg, gall, blood, milk, urine, mussel, and horn (L G The best of these is hair, then brain, then egg, then the skull, then blood, then horn).“

But when I turn to Stapleton, Azo and Husein’s Chemistry in Iraq and Persia in the tenth century ad, page 378, I find,

“They are ten stones 1) hair, 2) skull, 3) brain, 4) bile, 5) blood, 6) milk, 7) urine, 8) egg, 9) mother of pearl, and 10) horn. The best of them is hair, then brain, then bile, then egg, then skull, and then blood.”

It seems that they used slightly different versions originally to translate from. The latter appear to have used several different sources for their translation whereas Ruska relied on just one.

And that’s about it. A very elusive fluid. It hardly crops up at all, despite many references in these works to the use of blood, eggs, urine and milk from animals. You might almost think that most such references were cover words….

Alchemical illustrations, colours and an odd vessel


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A friend linked to a short online collection of pictures of alchemical manuscripts, which included a 15th century Germany/ Austrian Donum Dei of pseudo-Arnaldian type, or at least it refers to him a few times.

Now the interesting thing is the vessel, which is unlike any I have seen elsewhere. It is like an upside down alembic, but sealed except for the spout. How precisely it is supposed to work is unclear. So that is the first mystery, although it might be based more on my lack of knowledge of alchemical vessels, and of course the lack of any real broad study of them despite their widespread existence throughout many hundreds of surviving manuscripts.

The second interesting point is the colours used in the pictures. There is of course a red king inside it, a white queen, as usual for 15th century alchemy, and one picture has this:

Which is the same odd sort of flask with lower half labelled aqua, the captions saying something to do with philosophical sulphur and whitening and cleaning the black and white.

But note the three red circles, three white, two green and two blue. Is this an accident that they are probably the four elements, red being fire, blue perhaps air, or what? Colours turn up frequently within alchemical illustrations and descriptions, but the only ones people have really noticed are the red and white. Of course the four elements correspond to specific colours too, but not always the same ones. Which is where it gets tricky, because previous research I have done couldn’t reach a decent conclusion about the use of colours within one alchemical manuscript, and if they had a definite purpose and meaning to them in the specific situation. In general, alchemists seemed to have different ideas of what each colour meant, or when it was supposed to appear in the alchemical work. Red, white and black are important, but not generally blue, which is associated more with one of the elements, air or water.

So if I were being adventurous, I would suggest that it means you need equal amounts of red and white and lesser of green and blue, and they might correspond to the four elements. But that is just speculation at this stage and it is more likely that they don’t mean anything. More research required as usual.

Buy my e-book

Over 2 years ago I wrote a little ebook:

Alchemy in Medieval and Tudor England

which those who have read it rather enjoyed.  It was the fruit of several years of research into alchemy, focusing especially on England in the medieval and Tudor times.  I drew together lots of research by other people into a nice simple time line that I think shows most of what you need to know about alchemy in that period, in England, and I made sure to give pointers if you wanted to go further into the matter.

However the wee company that was set up to publish these ebooks isn’t doing so well, so it’s more of a buy it now while you can moment, and we’d all like it if you did.


The bigger book I am working on will have 4 times the words, and lots of experiments, but is a pan-european book, with less local information and colour.


A practical alchemy mystery


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Whilst distilling at the weekend using a long glass worm to ensure good condensation, I started wondering about the practicality of it all. What I just have not seen in alchemical images showing furnaces and distillation and sublimation and the like is a way of holding all the equipment in it’s proper place. Nor has this been mentioned much if at all in the texts.

For someone interested in the practical side of alchemy, that is an immediate red flag. Maybe all the images I used to think were based in practical reality weren’t!

For instance, here you can see a clamp holding my condensing worm in place:

New serpent in action

So I had a look through various sources.

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