Cennino's Apprentice

In the 14th century, an Italian painter named Cennino Cennini wrote a text on the techniques of painting. None of his paintings are known to have survived but we know how he worked and that is perhaps better for history.

I'm going to see if I can teach myself these methods and document them as I go along.

The original Libro dell'Arte is in Italian, of course, but has been translated several times in various editions. I'm using a combination of the 1859 Italian edition (machine translated into English as necessary) and Daniel V. Thompson Jr's 1933 translation of that edition for Yale University Press (currently published by Dover) known as The Craftsman's Handbook. I also have at hand a copy of Henley's Formulas and Lindsay's Chemical Cross Reference to provide me with slightly more modern instructions on some of the recipes Cennini glosses over. I'll find (and share) other sources and resources as I go along.

Cennini is a product of his time. He's quite religious. He advocates apprenticeship. He assumes knowledge that's been long forgotten. His writing and the translation are at turns complicated and sparse.

This should be quite an adventure. Will I be able to decipher 14th century instructions into something that makes sense to me? Will I be able to find the materials I need? Will the neighbors complain of foul stinks and plumes of acrid smoke? Despite the numerous likely pitfalls, I'm looking forward to making my own charcoal drawing sticks, mixing up a glue from lime and cheese, and trying my hand at gilding.

How to Navigate the Site
I've divided the site into the different sections in the book: Drawing, Colors, Fresco, etc and will go through each of them in turn, so until I finish the project (years after I begin, I imagine) there will be categories that are blank. The full category listing is on the home page

To read my adventures chronologically, which include Cennino's text, my comments, questions, trials, errors, discoveries and experiences, start with January 2007.

Or search for a specific word or phrase from the home page.

Who Am I?
There's an unanswerable philosophical question! But some stats are:

Born: April 1966
Nationality: American
Residence: Tokyo, Japan
Occupation: dilettante creative person
Blood Type: A

If you want to know more about me, scan through mediatinker.com where I've been posting since July 2000. Or look at some photos I've posted to Flickr. Or Google for "kristen mcquillin" and see what embarrassing things pop up.

Posted by kuri at 12:01 PM | Permalink

Here begins the Craftsman's Handbook, made and composed by Cennino of Colle, in the reverence of God, and of The Virgin Mary, and of Saint Eustace, and of Saint Francis, and of Saint John Baptist, and of Saint Anthony of Padua, and, in general, of all the Saints of God; and in the reverence of Giotto, of Taddeo and of Agnolo, Cennino's master; and for the use and good and profit of anyone who wants to enter this profession.

In the beginning, when Almighty God created heaven and earth, above all animals and foods he created man and woman in his own image, endowing them with every virtue. Then, because of the misfortune which fell upon Adam, through envy, from Lucifer, who by his malice and cunning beguiled him--or rather, Eve, and then Eve, Adam--into sin against the Lord's command: because of this, therefore, God became angry with Adam, and had him driven, him and his companion, forth out of Paradise, saying to them: Inasmuch as you have disobeyed the command which God gave you, by your struggles and exertions you shall carry on your lives.' And so Adam, recognizing the error which he had committed, after being so royally endowed by God as the source, beginning, and father of us all, realized theoretically that some means of living by labor had to be found. And so he started with the spade, and Eve, with spinning.

Man afterward pursued many useful occupations, differing from each other; and some were, and are, more theoretical than others; they could not all be alike, since theory is the most worthy. Close to that, man pursued some related to the one which calls for a basis of that, coupled with skill of hand: and this is an occupation known as painting, which calls for imagination, and skill of hand, in order to discover things not seen, hiding themselves under the shadow of natural objects, and to fix them with the hand, presenting to plain sight what does not actually exist. And it justly deserves to be enthroned next to theory, and to be crowned with poetry. The justice lies in this: that the poet, with his theory, though he have but one, it makes him worthy, is free to compose and bind together, or not, as he pleases, according to his inclination. In the same way, the painter is given freedom to compose a figure, standing, seated, half-man, half-horse, as he pleases, according to his imagination.

So then, either as a labor of love for all those who feel within them a desire to understand; or as a means of embellishing these fundamental theories with some jewel, that they may be set forth royally, without reserve; offering to these theories whatever little understanding God has granted me, as an unimportant practicing member of the profession of painting: I, Cennino, the son of Andrea Cennini of Colle di Val d'Elsa, -[I was trained in this profession for twelve years by my master, Agnolo di Taddeo of Florence; he learned this profession from Taddeo, his father; and his father was christened under Giotto, and was his follower for four-and-twenty years; and that Giotto changed the profession of painting from Greek back into Latin, and brought it up to date; and he had more finished craftsmanship than anyone has had since], -to minister to all those who wish to enter the profession, I will make note of what was taught me by the aforesaid Agnolo, my master, and of what I have tried out with my own hand: first invoking High Almighty God, the Father, Son, and Holy Ghost; then that most delightful advocate of all sinners, Virgin Mary; and of Saint Luke, the Evangelist, the first Christian painter; and of my advocate, Saint Eustace; and, in general, of all the Saints of paradise, Amen.

Posted by kuri at 01:06 PM | Permalink

How Some Enter The Profession Through Loftiness of Spirit, and Some, For Profit.

It is not without the impulse of a lofty spirit that some are moved to enter this profession, attractive to them through natural enthusiasm. Their intellect will take delight in drawing, provided their nature attracts them to it of themselves, without any master's guidance, out of loftiness of spirit. And then, through this delight, they come to want to find a master; and they bind themselves to him with respect for authority, undergoing an apprenticeship in order to achieve perfection in all this. There are those who pursue it, because of poverty and domestic need, for profit and enthusiasm for the profession too; but above all these are to be extolled the ones who enter the profession through a sense of enthusiasm and exaltation.

Fundamental Provisions For Anyone Who Enters This Profession.

You, therefore, who with lofty spirit are fired with this ambition, and are about to enter the profession, begin by decking yourselves with this attire: Enthusiasm, Reverence, Obedience, and Constancy. And begin to submit yourself to the direction of a master for instruction as early as you can; and do not leave the master until you have to.

Into How Many Sections And Branches The Occupations Are Divided.

The basis of the profession, the very beginning of all these manual operations, is drawing and painting. These two sections call for a knowledge of the following: how to work up or grind, how to apply size, to put on cloth, to gesso, to scrape the gessos and smooth them down, to model with gesso, to lay bole(*), to gild, to burnish; to temper, to lay in; to pounce, to scrape through, to stamp or punch; to mark out, to paint, to embellish, and to varnish, on panel or ancona(*). To work on a wall you have to wet down, to plaster, to true up, to smooth off, to draw, to paint in fresco. To carry to completion in secco(*): to temper, to embellish, to finish on the wall. And let this be the schedule of the aforesaid stages which I, with what little knowledge I have acquired, will expound, section by section.

I bring my enthusiasm and as much reverence, obedience and constancy as I can muster. I hope that my intellect will take delight not only in drawing but in learning an ancient art. As for the rest, I'm really going to start from scratch.

I know how to work with modern materials purchased from an art supply store. I can draw with pencil on paper, paint in acrylics, carve linoleum blocks with machine-formed blades. Fortunately for me, Cennino starts off easy in the next section, with drawing on a panel.

(*) Bole is a reddish colored clay. An ancona is a panel with mouldings. Secco is painting on dry plaster.

Posted by kuri at 01:16 PM | Permalink

How you Begin Drawing On A Little Panel; And The System For It.

As has been said, you begin with drawing. You ought to have the most elementary system, so as to be able to start drawing. First take a little boxwood panel, nine inches wide in each direction; all smooth and clean, that is, washed with clear water; rubbed and smoothed down with cuttle such as the goldsmiths use for casting. And when this little panel is thoroughly dry, take enough bone, ground diligently for two hours, to serve the purpose; and the finer it is, the better. Scrape it up afterward, take it and keep it wrapped up in a paper, dry. And when you need some for priming this little panel, take less than half a bean of this bone, or even less. And stir this bone up with saliva. Spread it all over the little panel with your fingers; and, before it gets dry, hold the little panel in your left hand, and tap over the panel with the finger tip of your right hand until you see that it is quite dry. And it will get coated with bone as evenly in one place as in another.

My questions:
Where do I find a boxwood panel?

What's cuttle? I think this must be cuttlebone, the same stuff they feed canaries. It can also be ground into powder for polish. That makes sense in this context.

"Enough bone"? What kind of bone? Cuttlebone? See below

Am I strong enough to grind bone "diligently for two hours"?

Cennino answers the bone question himself just a bit further on:

Silver-Point Drawing - What kind of Bone is Good For Treating the Panels

You must know what bone is good. Take bone from the second joints and wings of fowls, or of a capon, and the older the are the better. Just as you find them under the dining-table, put them in the fire; and when you see that they have turned whiter than ashes, draw them out, and grind them well in the porphyry; and use it as I say above. The thigh bone of a gelded lamb is good, too, and the shoulder, calcined in the way described.

Chicken wing bones. Easy enough. But of course his answer raises a few more questions, not to mention a wonder at state of the 14th century dining room floor.

What's a porphyry? According to the dictionary it's a very hard, igneous rock with crystals in it. I am going to venture that this is what his mortar and pestle were made of.

How does one throw bones on a fire in a modern Tokyo apartment? I'm thinking the Weber grill must be about the only fire I'm going to get. I'm certain Tod will be happy to cook some lamb while I burn my chicken bones.

Cennino also mentions some other kinds of panels.

How To Draw On Several Kinds of Panels.

For that purpose, a little panel of old fig wood is good; and also certain tablets which tradesmen use, which consist of sheep parchment gessoed and coated with white lead in oil, following the treatment with bone according to the system described.

So I guess I don't necessarily have to find boxwood panels if I can find fig wood ones instead. Or I can make some gessoed, lead-coated sheep parchment. I think I'll stick with boxwood.

I realise now that not only do I have to translate from 14th century to 21st century, but I'm also going to learn a lot of Japanese so that I can explain to shopkeepers just what I'm doing and why I need esoteric chemicals and animal skins.

大切な言葉
cuttlebone イカの甲
boxwood ツゲ材
sheepskin parchment 羊皮紙
mortar and pestle すり鉢とすりこ木
white lead (lead carbonate) 炭酸鉛

Posted by kuri at 01:33 PM | Permalink

Armed with the word for boxwood in Japanese, tsugezai, I started doing some research on the Internet to see if there was a convenient place to buy some panels to draw on. Shogi tiles are made of boxwood, as are traditional wooden combs, so I figured it might not be too hard to locate. But nothing on the web pointed to a lumber yard selling boxwood planks.

So I went off to Tokyu Hands, the popular and vast DIY/art supply/trendy homeware store. They seem to have everything you could ever want, until you want something specific. I poked around the exotic woods section for a while before asking someone about tsugezai. He led me over to a small heap of mug-sized logs. Tsugezai, but not in the format I needed. Still, it gave me a chance to see and feel it.

Boxwood is very dense. It is fine grained, heavy and almost waxy along its cut edge. What could substitute for that? I decided to buy a variety of small wood planks marketed as "postcards" until I can get my hands on some proper boxwood.

Walnut is dark wood with a fine grain. It feels quite smooth and I when I press a thumbnail hard across it, it makes only a slight indentation in the wood.

Oregon pine has a large uneven grain, almost lumpy. It dents easily when I run a thumbnail across it. Not suitable for drawing, I think.

Japanese cherry, sakura, is commonly used for carving woodblock prints. It is finely grained, heavier than any of the other woods I have and does not impress easily with a thumbnail. I think this one will work best, so I bought a larger piece of it as well.

Elm, called nire in Japanese, alternates narrow bands of hard and soft woods. Even milled, it's a bit rough to the touch and rather soft.

Japanese horse chestnut, tochi, is very pale with a fine grain the has a watered silk-like pattern. It does not pass the thumbnail test - too soft to draw on.

I will continue to look for boxwood, but in the meantime, will begin to prepare the sakura and walnut boards by watering and polishing them with cuttlebone powder.

Posted by kuri at 10:55 AM | Permalink

Wow, that really works. Cuttlebone is 14th century sandpaper.

I found a cuttlebone at the pet store. I don't know that you can get them anywhere else and though I had a look around the jewelry making supplies at Tokyu Hands, I didn't try anywhere else. 21st century pet parakeets around the world keep the cuttlebone industry alive and well. That's good enough for me.

I also purchased a ceramic mortar and pestle so that I could grind the cuttlebone into powder. As it turns out, that was unnecessary. Jim explained how he used cuttlebone when he did antique paper restoration (I have a friend who has done paper restoration, wow), just peeling off the hard shell and rubbing the softer inside part against the paper.

I decided to try it both ways.

Ground cuttlebone

I broke off a bit of the cuttlebone and crushed it up in the mortar, then ground it for about 5 minutes to produce the powder pictured above. I sprinkled it on the sakura board and rubbed it in with a piece of unbleached muslin. It worked pretty well, especially when I took a teaspoon of the powder, wrapped it in the cloth and used that against the board.

Cuttle polishing directly on the board

But Jim's method worked better and it was easier since I didn't need to grind the cuttle first. After going over it thoroughly with the cuttle and producing a lot of dust, I used my powder-filled cloth to continue the polishing.

I discovered (maybe re-discovered is truer) that I am impatient with the work, so I put on some old pop music and sanded the big board for a full two songs. Then I dusted everything off with a clean rag and went to rinse the boards clean.

Cennino says

...smooth and clean, that is, washed with clear water; rubbed and smoothed down with cuttle such as the goldsmiths use for casting. And when this little panel is thoroughly dry...

I didn't wash the boards first, because I assumed that modern milling and distribution practices are pretty clean and tidy. Tokyu Hands is not full of sawdust. But I should not think I know better than my master. When I washed the boards after polishing, all of them but the walnut raised up their grain and became rough and scratchy. Maybe boxwood would behave differently. Regardless, now they are drying in the chilly, dry winter day. When they are dry, I will polish them again and simply do a very good job of dusting off the excess powder, instead of washing them clean.

I had chicken wings for lunch today just so I could get some bones. Yesterday my friend Maeda-san at Amorosso gave me some lamb rib bones (not the thigh or shoulder bone that Cennino recommends and who knows if the lamb was gelded, but I'll try the ribs and see how they go) Tonight I will fire up the BBQ and toss my chicken and lamb bones into the coals and see if I can get them to turn "whiter than ashes."

Posted by kuri at 12:19 PM | Permalink | Comments (1)

Note to readers: I changed the site's directory name today. I realised too late that I had failed to rename it from libro to cennino before launching it. Fortunately, I may be the only person looking at the site regularly. If by chance you previously bookmarked Cennino's Apprentice or subscribed to the RSS feed, I'm sorry but you'll need to do it again.

Posted by kuri at 07:36 AM | Permalink

I entered the realm of alchemy when I tossed the chicken and lamb bones into the hot coals in the Weber grill on Friday night. First there was a huge amount of flame as the meat and fat burned off. We stood back and watched (so did one of our neighbors). "That a lot of calories," Tod commented.

Heating the bones

After the fire settled down, we watched the bones turn from charred black to white as they heated up and burned away everything but their calcium. This is called calcination. It's one of the 12 vital processes alchemists used to transmute substances.

Calcium shells of chicken and lamb

After about half an hour or so, the bones were "whiter than ash" and I drew them from the fire. They were lightweight, brittle and chalky. They cooled very quickly; when I photographed them less than five minutes after taking them out of the coals, they were room temperature.

I can understand why alchemists were impressed with calcination.

Posted by kuri at 08:46 AM | Permalink

First crunch. They were so brittle that they broke up quite quickly under the pestle.

Now I answer my earlier question " Am I strong enough to grind bone 'diligently for two hours'?"

Yes, I am, but after about 45 minutes of diligent grinding, my arm gets tired. So I broke the task up and spent a couple of days grinding first the calcined chicken bones, and then the lamb rib bones in a second batch. Four hours of diligent grinding in total.

Powdered chicken bone ready for storage in an origami folded packet

The chicken bones came out somewhat cakier - just a tiny bit more moisture in the bones, I guess - and a bit greyer from some soot on the bone ends. The lamb bones were somewhat crispier and a little bit harder to grind smooth. Even after two hours of grinding, they weren't quite as perfectly powdery as the chicken bones. Probably if I'd followed Cennino's instruction to use lamb thigh or shoulder bones, it would have worked better. Always do what the master says...

Grinding is tedious, but it gives me a chance to listen to audio books or watch crap on YouTube. I'd better get accustomed to the task because I've read ahead in the book and I know that I will be doing a lot of grinding in the upcoming months.

Posted by kuri at 10:30 AM | Permalink

The problem with being an apprentice to a man who has been dead for hundreds of years is that he's not here to watch over and give advice. I tried to prime the boards with the ground bone yesterday, but something's not right.

...take less than half a bean of bone, or even less. And stir this bone up with saliva. Spread it all over the panel with your fingers and before it gets dry, hold the little panel in your left hand and tap over the panel with the finger tip of your right hand until you see that it is quite dry. And it will get coated with bone as evenly in one place as another.

So there were my instructions. I decided a "bean" should be about the size of a fava bean since I know those are popular Italian beans. Half a fava is about a lima, I reckoned. So with a lima's worth of lamb bone, I worked up a good bit of spit and mixed.

A splotchy smear of bone-and-spit

The mixture was uneven and difficult to apply smoothly. If I went over it twice with my fingers, it smeared around and left streaks. It seemed terribly transparent, too. By the time I'd gotten the board covered in bone, half a minute or so, the board was already semi-dry.

Holding it and tapping didn't seem to do anything, really. I tried holding it vertically and tapping on the surface with my finger. That succeeded in tapping fingerprints into the prime. I tried holding it horizontally and tapping the edge and bottom surfaces. That did make one largish crumble flake off and skitter over the board, but not exactly "evenly in one place as another." I wondered if he meant a motion more like greasing and flouring a cake pan, but that also didn't have much effect.

Daunted, I gave it a break and let it dry. The primer became more opaque, but it also felt sort of slippery and easily brushed off the surface of the sakura board, especially in the areas that were more thickly applied.

I gave the other two boards a coating of chicken bone mixture with not much more success.

Drying boards and grungy fingers

The walnut board, which is the smoothest one, produced the most satisfactory but even it seems too transparent and fragile a surface to draw on. The two sakura boards are so uneven and lumpy that I will brush them down and try again. Maybe a second coat on top of a thin first coat will be an improvement.

It makes me wonder where I've gone wrong: wrong wood? Are the bones not calcined or ground correctly? Too much spit? Not enough? Is my 21st century saliva too different from Cennino's?

If he were here, he'd look at my mistakes, show me what to do, and I'd be on my merry way. As it is, I'll search for online resources on silverpoint drawing (for this is where the preparation of the little panel leads next) and hope that I twig to some great insight soon.

Posted by kuri at 04:04 PM | Permalink

I've been poking around trying to find more information about priming the little panel. Here are some excerpts from various websites I've read. Most use Cennino as a primary source!

Gesso would be used to coat the surface of the panel. The recipe would vary from studio to studio, though in its simplest form would consist of a mixture of calcinated lime and a binder. The binder was usually animal hide glue for permanence of just spit if it was just an exercise by an apprentice. For the calcinated lime, the thigh bones of a chicken would be burned to a fine white ash. Add that to the glue with some white lead and you have medieval gesso. This would be rubbed into the grain of the panel to be practiced on.

[...]The surface of the panel has to be relatively rough so that the gesso can have a good grip. It tends to flake off, otherwise. Gesso, if you're not into burning chicken bones and mixing with white lead, can be purchased from an art store or even from Walmart. Usually, about 3 layers of gesso (with 1 hour between coats) will do it.

Silverpoint by Callista Magdalena di Scarlatti perhaps lifted from The Art of Silverpoint Drawing

I learned a lot about the purpose of ground at SilverPointWeb. They sell their own magic formula of ground, but the fundamentals are the same: ground is an abrasive that grinds away the silver from the point. In its instructions for use, SilverPointWeb suggest three to four coats of ground with the initial coats lightly sanded after drying.

American egg tempera artist Fred Wessel uses this technique for preparing his panels. This seems a bit too complex and perfectionist for my apprentice's practice panels, but it's good to understand how I may be doing it "for real" later on.

His procedure for preparing the panel was to glue a piece of linen canvas to the seven-ply plywood, size the surface with rabbit-skin glue, and then apply six layers of traditional gesso made from rabbit-skin glue and whiting. After allowing the layers of gesso to dry, Wessel rubbed the surface with charcoal dust to reveal imperfections and then carefully scraped them with a sharp, two-inch blade from a carpenter's plane. When the gray left by the charcoal dust was gone, he knew the surface was perfectly smooth.

Using Egg Tempera and Gold Leaf to Achieve Renaissance Luminosity by M. Stephen Doherty

So I will close this post and get back into the 14th century to apply more coats of bone-and-spit. When I'm ready for a break, or waiting for coatings to dry, I'll be checking out the conversations at the Cennini Forum.

Posted by kuri at 09:36 AM | Permalink | Comments (3)