Myths and Bullshit Around Quenching
|Hint: The juicy part will be at the end!|
|Recipes from "Stahel und Eyssen"|
|The general literature about iron, steel and swords supplies a number of quaint if rather disgusting old recipes for making good quenching "juices". Here is one for a first taste treat:|
|It looses a bit in the translation ("Bocks seychen" is rather more earthy than he-goat urine) but you get the drift.|
|This first recipe is
from the book "Stahel und Eyssen"
(Steel and Iron). It was printed 1534 in Mainz (where printing was invented by
Gutenberg in 1450). This book is the only source for all those cute recipes
that everybody likes to reproduce in the context of iron and steel history.
Let's have a few more:
|That is the first page of the book,
starting with the headline "Firstly, how iron is
hardened and released again" and then gets immediately down to
So what the hell is vervain? Or cockchafer grubs? The present German word for "vervain" is "Verbene" and that doesn't help all that much either. In the original, however, it is "Eysenkraut", iron herb. Other German names are "Eisenhart" (iron hard) and "Stahlkraut" (steel herb). Aha. Now we get an idea.
Here is vervain:
|Vervain, it appears, was one of the major
"miracle plants" in many cultures from antiquity to modern times.
Good for about anything from hardening steel to curing diseases or for cleaning
things. As far down the time scale you care to look, vervain comes up in
recipes for about everything. The ancient Egyptians seem to have used it, the
Celts, and so on. You know it, if you know it at all (assuming that you are not
overly given to esoteric stuff), as a some unobtrusive weed.
Now let's look at the cockchafer grubs. A cockchafer grub ("Engerling" in the original) was a very well know kind of "worm" (and there is no "little" in the original) before around 1930. Here it is:
|Those things are big! And juicy. They used to be around by the billions, like crickets in biblical plagues, and constituted a big part of country life and lore in Europe. I have encountered huge swarms of the bugs when I was a kid. There are plenty of recipes for May-beetle soup in old cook books. It's supposed to be good.|
|One more recipe for hardening:|
blood (Trache blut)? In the 16th century?
Just look at the beginning of this recipe (not contained in the translation). There you find "Trachen wurtz" or dragon herb. That gives a clue: Dragon's blood refers to a ground-up bright-red resin that was obtained from a number of distinct plants. It would have been a bit difficult to get the "real" stuff in the 16th century (or at any other time).
Note that a really useful advice is also given: Keep your steel clean!
|There are plenty more recipes for hardening iron and steel but also quite a number for softening it. This probably implied to make a quenched steel less brittle; what we do in more modern times by a bit of tempering after the quench. Here is one:|
|The rest (and many more recipes) give the by now usual mix of weird things.|
|Now a question comes up: People might
have been superstitious, ignorant and stupid during most of the human history
on this planet. But certainly not all people at all times, as these recipes
seem to indicate?
Well, no they weren't. If you consult all of the book, you realize:
|What more do you want?|
|I think it is quite telling that the
the first chapter has the headline:
"Firstly, how iron is hardened and released again" while the second
chapter opens with: "Following now the pieces how one should harden
steel". The author, like everybody else, knew the difference between iron
and steel. Iron was the stuff that we now call wrought iron or low carbon
steel; i.e. the stuff that does not form martensite and thus cannot be quench
hardened. It also might have contained phosphorous steel that can't be quench
hardened either. Steel ("Stahel") in contrast is whatever responds to
quenching, i.e. medium carbon steel.
It follows that all the concotions for hardening iron are not so much recipes for quenching "juices" but describe carbon and / or nitrogen sources for case hardening by "carbonizing" the surface.near regions. In some descriptions (in particular older ones, see below) the (solid or pasty) mixtures are used by heating the iron in the stuff, as required for effect. Of course, some confusion with quenching is to be expected and thus recipes for liquids in which to quench iron are found, too.
|The whole book should be seen like a modern 500 page "Of health and beauty" book. On the first page it says: Eat healthily, exercise, don't get overweight, and wash yourself regularly with water and soap. On the remaining 499 pages it states (in spirit but not in the exact words following): In addition, you also could buy and apply the products and procedures detailed in what follows; the more exotic and expensive the better (for the seller). It will help some, provided that you always follow the advice on page 1.|
|Was there anything good about all the stuff you
pitch into water for proper quenching of steel? As far as the hardening of
iron is concerned, some recipes are not
really about quenching but about getting some carbon / nitrogen into the outer
skin of the soft wrought iron as outlined above. For that you need all this
biology as a carbon / nitrogen source, water certainly would not do any good.
As far as martensite production in carbon steel by quenching is concerned, whatever you add to water tends to decrease its thermal conductivity a bit, making quenching a little slower and the blade a little less harder but also less brittle. So yes, if everything else is just right, pissing into your quenching fluid might do a bit of good.
There might have been other fringe benefits, however. Your customer was probably willing to pay more for a blade that had been made with the help of extremely fancy stuff. In particular if there were convincing explanations. Clear water running forcefully down a ravine cannot but impart more "force" to a blade than murky water from some boring lake. It's called "sympathetic magic" and that works up to this very day (for whoever sells it).
Quenching in expensive and magic stuff just must be better than doing it in cheap stuff. That is an easy claim to make if there is no way of a quantitative comparison. Nobody then could measure hardness in a quantitative way, so claiming that my sword is harder than yours was without much risk. In contrast, claims to who has the longest are open to measurements. I just read in a newspaper that Lana Turner has rated Ronald Reagan's sword lengths "40 minutes" while J. F .Kennedy just got a humble "4 minutes". S. Freud would have understood.
|The "Stahel und Eyssen"
book from 1534 is not the only medieval reference to quenching. There is also
"De diversis artibus" (about various arts), written around 1100 -
1125 by one Theophilus
Presbyter. probably a pseudonym for Rogerus von Helmarshausen, a
benedictine monk who also was a well-traveled gold smith. The book or better
books (not completely preserved) deal with gold smithing, painting, casting
bells etc. and contain detailed recipes for making, e.g., files, piercers and
Here is one for gravers; pointy tools for engraving:
|Nothing wrong with that. More interesting is the hardening of files. Files, according to Theophilus, were made from massive steel but also from (soft) iron.|
|Nothing wrong with that either, First carbonize the ridges of the file, than quench harden and temper a bit at lower temperature. There are more and similar recipes like this, and then there is the juicy one that made it into quenching folklore up to this day:|
|With regards from Baphomet, Mephistopheles, or whatever name you prefer for the horned and red-haired one who walks on goat's feed. A little magic can never hurt, even if it is thinly disguised black magic.|
|All in all, the medieval smiths knew a few things that worked. Then they knew a lot of things that neither worked nor did much damage for the iron / steel - but could do a lot of good for the smith's purse!|
|Did some ancient
smiths, presumably in the "East", quench their red-hot blades in the body of a
live person? This is a question that exercises several Internet forums
quite a bit. A lot of people have run across indirect reports of this inhuman
technique and became upset. Nobody, it seems, knows the text to that claim.
Here it is:
|I have involuntarily helped to spread this gruesome tale because I translated and used it in one of my hard-core Science hyperscripts in a "on the side" module" 4). Here it is:|
| In his book Stephe Sass put this quote into the
context of wootz
blade forging. So where did Steve get this atrocious tale from? He quotes a
book from one J. G. Thompson5) as
the source. The Internet seems to know nothing about Thompson and his book. I'm
sure, however, that Steve Sass had access to it; the library of Cornell
University (where Steve works) is famous for its huge collection. I'm equally
sure that Thompson has his quote from somewhere else. Maybe in time the
original source of this quote will be unraveled but I expect that nothing
definite will be found. (Turns out I'm wrong; read on).
Meanwhile everybody seems to have run across this "rumor" either by hearsay or by written reference to it. All the BS that was published around the secrets of the damascene / wootz blade, e.g. in the august New York Times3), seems to be especially fertile ground.
|Since we have no unassailable
records, we have to use ratiocination. The first question in this context then
would be: Where those ancient (oriental) smiths cold-blooded enough to kill a
human if his blood made for better blades?
The answer to that question is very likely a resounding YES! People were killed for smaller potential gains without much qualms. In particular slaves but also siblings, wifes, and you or me.
The second question than must be: Did killing a human by plunging a red-hot blade through his body really make for better blades? Better than just plunging it into anything not alive?
The answer to that is a definite NO! It is easy to see why:
|I have discussed what you can do
with quenching, what you cannot do, and what can go wrong in some detail in the
backbone. So let me
just give the essence of the argumentation here:
|The next question thus is: OK.
Killing a slave by quenching makes no sense at all. We know that now.
But did the ancient guys also know that then?
I doesn't matter, after all, what we know,, it only matters what blade makers and their customers believed. Nobody could assess the exact hardness of a blade in a quantitative way in old times and it was impossible to be sure if your slave-quenched blade was better or not compared to a normally quenched one. It was a matter of believe. People believe strange things after all, for example that a BMW is better than a Mercedes.
Answering that question is impossible. My feeling is that here or there some rich idiot who could afford one of these extremely expensive swords would be capable of believing the tale. So one cannot rule out that some smith followed the procedure on occasion.
That, however, triggers the next question: Is it technically possible to quench a sword, however badly, as described? The answer is: NO! The "fleshy parts" are just not large enough. Cooling rates would be quite different in different parts of the sword and that is very bad. And only the first thrust would have any effect anyway.
The final question is: Does the tale contain internal inconsistencies? The answer is a resounding: YES, it does! Let's see what there is:
|In other words: The whole thing is a joke!|
|Aren't' you impressed by my powers of ratiocination? I certainly am. Because it turns out, I was right. After I have come to the conclusion above, I found what appears to be the original source6) of the English version of the tale:|
|Aha! A discovery made by Prof von
Eulenspiegel! That sounds
rather good - except if you know, like every
German, that "Eulenspiegel" is never the name of a person
but a synonym for a trickster, somebody who plays you for a sucker.
Moreover, a copper cylinder was found that contained the ancient smiths' secret in writing! That must be the only copper cylinder used for keeping writings that was ever found in antiquity. Moreover once more, it contains writings from the the only ancient smith known to humankind who was capable of writing. Yes, indeed!
|So some evil German at the end of the
19th century invented the story and spread it, disguised as archaeological
discovery? Not so. Every German reading the Berliner Tageblatt around 1894
would have immediately realized that the article was a joke or a satirical
comment to the craze about "damascene steel" that
scientists and "damascene steel" aficionados mightily in these times.
I would not be surprised eiher if it turns out that the article was originally published on April 1st.
|How this kind of urban mythe spreda from the initial Chicago Tribune article can be read in a short article from Stephan C. Alter from 2017, entitled: "On Slaves and Silk Hankies. Seeking Truth in Damascus Steel".|
|1)||The 1524 book
"Stahel und Eyssen, künstlich weych und hart zu machen,
schrifft und bildwerck darinn zu etzen: Gold unnd silberfarben, auff ein yedes
metal mancherley weyse zu machen. Auch mancherley lötung zu stahel, eysen
und messing, kalt und warm ; Schmaltz flecken, öl flecken, oder was es nur
für flecken seind, auss Gewandt, Sammat, Seyden, Güldinen
stücken, Cleydern etc. leychtlich mitt wassern oder laugen, darzu bereyt,
on schaden zu vertreiben: eins yeglichen gewandts verlorn farb wider zu
bringen. Auch garn, Leynwath, Holtz, Beyn etc. Mancherley farben zu ferben.
Getruckt zu Meintz [Mainz] bey Peter Jordan, 1534.
|2)||Stephen Sass: "he Substance of Civilization: Materials and Human History from the Stone Age to the Age of Silicon", Arcade Books;|
|3)||WALTER SULLIVAN: "THE MYSTERY OF DAMASCUS STEEL APPEARS SOLVED" Published: September 29, 1981 in The New York Times|
"Einführung in die Materialwissenschaft I"
http://www.tf.uni-kiel.de/matwis/amat/mw1_ge/index.html; advanced module t4_1_3 "Mythen der Schmiede"
|5)||J. G. Thompson:
"Mining and Metallurgy"
New York, American Institute of Mining and Metallurgical Engineers publication, May 1940.
Numbers and Concentration
The Eigenmodes of a Sphere
Swords and Symbols
The Frankish Empire And Its Swords
Dislocation Science - 1. The Basics
11.5.3 Forging a Wootz Sword
11.6.3 Making a Japanese Sword - Part 2
Medieval and Modern Texts Concerning Crucible Steel
Science of Uniaxial Deformation
Bending a Sword into a Circle
Science of Deformation
Quantifying the Properties of Your Sword
© H. Föll (Iron, Steel and Swords script)