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 (http://www.trinitycourtpotteries.co.uk/), 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 (http://www.todsstuff.co.uk/knives-domestic/penknives-domestic.htm), 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.

Continue reading

Why I’ve not been posting so much recently


I’m afraid I haven’t been posting as much as I would like. This is due to several things. Firstly I have the bad habit of having multiple projects on the go, so each individual one takes longer to complete than if I did them one after another, although it does mean I approach each one refreshed on a regular basis. Secondly, I have a full time job, so between that and the commuting and such, I don’t have the time and energy to do experiments and research that I did 3 or 5 years ago. I can at least afford to buy some new equipment.

Having said that, I am almost back to normal with regards to energy and fitness, the problem there being that I have to regularly exercise to maintain it, including climbing mountains and suchlike, which of course takes up time that could also be occupied by experiments.

Finally, the most important reason is that I am getting on with the long mooted book on alchemy that I started at the end of 2010. Had I known then what I know now about how complex alchemy is and how tricky the experiments can be, I’m not entirely sure I would have started writing it. Nevertheless, it is at least half complete, with every chapter at least roughed out. The only thing is, I need to do more experiments, and because they are going in the book I can’t put them online, otherwise why would you buy the book?

I also need to find a publishers. All suggestions welcome, but bear in mind this is a popular introduction to alchemy with lots of colour pictures, which will somewhat limit the interested or indeed capable companies.

I’m also pushing on with my experimental history of alchemy research, for which I have already done some test work reported on here, now I just need to repeat it all, with better equipment than I had last time, and write it up. Research for the write up stage is ongoing, but of course takes time to do as well.

Finally, it can be hard to find actual alchemical experiments and related topics that I can do, because either they involve really nasty chemicals, or else I’ve already done them. So as usual all suggestions welcome.

And another one bites the dust


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The cucurbit I used a couple of weeks ago for a distillation broke when I held it by the neck. Being pyrex I thought it would be a bit stronger, but obviously the weight of lute around the bottom and some sort of flaw in the glass, perhaps brought on by too much heat or the time I heated it without lute and it changed shape slightly, meant it could only do a few more high temp distillations.

When I picked it up by the neck, the base dropped off onto the floor and the lute was cracked off it:

broken luted cucurbit

When I looked closer at the break point there was some copper on the outside of the glass, stuck in the lute, suggesting that a hole had opened up at some point in the distillation.

Broken edge of cucurbit

Ah well, I shall have to buy a new one, or make that several, because it seems they don’t last long enough. This time I shall know to be even more careful with it. It actually make the 3rd pyrex cucurbit I’ve broken over the last 9 years, but then I’m not doing as many distillations as I would like.

This kind of breakage was a common problem for alchemists, which is both why they luted cucurbits and complained about the fragility of glass and stuff. Well, having written that, I can’t immediately find any nice and relevant quotes; if you can think of any please let me know.

Actually, sometimes I think I’m engaged in making broken stuff for beginner archaeologists to study. Maybe I need to find someone willing to pay for real soda glass equipment and we can study how well it survives being used.


The importance of good lute


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Once again whilst distilling I was reminded of the importance of a good lute. That is, the stuff that serves to hold the glassware together, forming a strong and impervious seal. Various recipes are given, depending on the circumstances and author. John of Rupescissa suggested paper, egg white and fine flour, which works nicely, especially with modern ground glass joints when making the quintessence of alcohol.

I wrote about lute a couple of years ago:


The obvious point is that the lute for glassware involves egg whites and stuff to hold them together, usually a mix of organic and sometimes inorganic stuff. The net result can be like this:



Lute at alembic and serpent

Which is egg white, fine flour and fine linen. It is not exposed to any temperature above 100C, but that is certainly enough to start cooking the egg and flour, which just so happens to make something a bit bready that expands slightly and seals any gaps. It also has the advantage of being easy to put in place, because it is soft and squishy. It certainly works and prevents the dangerous and irritating loss of the substances being distilled.

In fact that makes me wonder when it went out of use. So, off to the old chemistry textbooks!

(Fortunately I collected a lot of scanned ones from archive.org a few years ago when researching a few things)

In the 10th edition of Griffin’s Chemical Recreations, from 1860, mention is made on page 180 of the old use of cork and cement, prior to the invention of cork borers and caoutchouc-tubes.

Various other textbooks don’t really go into practical chemistry at all.

So a question that will take a lot longer to answer than I had hoped.

Anyway, here’s another picture, this time showing my new serpent in action:

New serpent in action

There’s over 3 feet of glass tubing here, which is just enough for the distillate to cool down and drip out of the end rather than rushing out as vapour, which was always a problem I had before. Note the coloured fabric, which is offcuts from my various re-enactment clothings, which are soaked with water. These hold the water close to the warm glass, which then heats them up and the water evaporates, helping cool the glass and then the vapour within it. You can even see steam rising from the cloths, although not in this photo.