Alfred's Improvements

Alfred the Great (849 - 899) was not an idle king, even when not battling Danish invasions to protect the shores of Great Britain.

Some of his reforms and innovations did involve the military, though. The traditional way to deal with trouble was for each small community to assemble its own men against an attack. The Danes, however, would attack swiftly a small area, conquer it, and fortify it as a new base from which to mount further attacks and to which they could retreat if their further military plan looked like it was failing. They could make steady progress across the country before a large-scale defense could be mounted by a king. After defeating Guthrum at Edington, Alfred used the following respite to plan a standing army, ready to march and strike at the first sign of invaders.

In order to do this, Alfred had to raise taxes. His people had what was called the trinoda necessitas (three-fold tax): obligations for military service, fortress work, and bridge repair. Alfred increased a landholder's taxes based on the productivity of his land. He also created over third fortified places in souther Great Britain from which he could organize resistance to invaders.

He also increased naval power. The Anglo-Saxon Chronicle claims that Alfred's ships were larger and faster than ships of the Danes or Frisians. Alfred wanted to stop invaders before they reached shore, if possible.

He was also responsible for some legal reforms. He gathered together many of the laws from the past, including the code of King Ine of Wessex (689 - 726), rejecting laws that didn't please him, and produced a law code of 120 chapters with a strong biblical influence.

Even while dealing with these many "royal obligations" he was encouraging changes in education and culture. Perhaps inspired by Charlemagne's re-birth of culture, he established a school at court for his children and others. He also arranged for translations into English of Latin works he felt everyone should know. Concerned that the Viking invasions were a sign of God's wrath, he founded monasteries and "imported" monks because he found little local interest in populating the monasteries. He made sure copies of Gregory the Great's Pastoral Care went to his bishops for the better preparation of priests.

Now, calling anyone "the Great" will always raise questions about the accuracy of the epithet, and Alfred is no exception. Tomorrow we'll hear why some modern historians claim he wasn't that Great. See you then.

Alfred versus Danes

After establishing the Danelaw that was supposed to bring peace between the Danes/Vikings and the Anglo-Saxons of the south, Alfred thought that his reign had eliminated major military engagements. With the death of Guthrum, with whom he had negotiated the peace, Vikings apparently did not feel obligated to honor the borders.

A fleet of 330 ships arrived on English shores in 893, including wives and children, indicating their intent to colonize, not just plunder and go. They settled At Appledore and Milton, both in Kent, and Alfred set up men to keep an eye on their movements. Alfred started talks with Hastein, the Viking chieftain in Milton, but while doing so, the group at Appledore started moving northwestward. Alfred's eldest son, Edward, defeated them in Surrey. A siege at Exeter was defeated by Alfred. There were other battles, until by 895 the Danes were running out of food and supplies. They retreated to the Thames, and fortified themselves 20 miles north of London, but they were outmaneuvered by Alfred who blocked the river. In 897 they retreated, some to Northumbria, some to East Anglia, some to their ships and back to Europe.

Alfred lamented the effect of Danish raids on England, especially education:

...learning had declined so thoroughly in England that there were very few men on this side of the Humber who could understand their divine services in English or even translate a single letter from Latin into English: and I suppose that there were not many beyond the Humber either. [Alfred's preface to his translation of Pastoral Care]

Manuscript production also suffered during these years; there was also much destruction of manuscripts when Danes burned churches and monasteries. An 873 document is so poorly made that a historian suggests the scribe did not even know Latin. Alfred had established a school for his own children and others, where they studied both English and Latin. He encouraged learning, especially in English, for everyone who had a mind to apply themselves.

His reign produced many other improvements and changes in the culture, and I'll talk about them tomorrow, before we sk the question: Was Alfred really great?

Alfred the Great

Alfred the Great (848 - 26 October 899) was not the King of England, because at the time there was no unified England. He was king of the West Saxons (Wessex), which covered much of the south of Great Britain.

His father, Æthelwulf, died when Alfred was about 10 years old, and the crown went in turn to three of Alfred's brothers, Æthelbald, Æthelberht and Æthelred, before Alfred was crowned in April 871.

His chief task as king was fighting off invasions by Viking. In 878, after the decisive Battle of Edington against Guthrum, Alfred made an agreement with the Vikings, granting to them northern England, the north-east Midlands, and East Anglia (an area that became known as the Danelaw) in exchange for leaving the rest of Great Britain safe from invasion. Alfred also convinced Guthrum to convert to Christianity, whereupon he was baptized with the name Athelstan.

This attempt at peace did not last. Alfred was forced to deal with more Danish incursions. In 885 there was a raid on Kent, an ally of Alfred in south-east England. The Danes besieged Rochester, whereupon Alfred gathered a large that caused the Danes to abandon Rochester and flee to their ships. A year later, Alfred reoccupied the city of London (which was not as important as it became later), rebuilding the Roman wall and making the city safe for habitation and trade again.

In that same year he was named King of the Anglo-Saxons. Contemporary chronicles claim that all Saxon kingdoms of the time recognized him as ruler. This unification of the Anglo-Saxons did not mean all things were going well. Guthrum-Athelstan passed away in 889, and the uneasy peace that had been brokered between him and Alfred began to dissolve. Alfred's kingdom was about to become embroiled in frequent battle with Vikings again. We'll look at the latter years of his reign tomorrow.

Let's Talk Clocks

What constitutes a "clock"? The Latin horologium could refer to a clock or a timepiece of a sundial or the building or structure designed to support any of those.

Modern horology, the study of the measurement of time, distinguishes clocks which mark time by striking something (the word "clock" comes from French cloche, "bell"), whereas a timepiece does not. So a timepiece can mean a watch, a sundial, a clepsydra, or an hourglass, etc.

The sundial was likely the earliest way to measure time: a shadow on a flat surface displays the progression of the sun.

The clepsydra (Greek κλεψύδρα, literally "water thief"), was used in Babylonb, Persia, and Egypt as far back as the 16th century BCE. The simplest form is a bowl or other vessel with a hole from which the water drains, and markings to match drainage levels with the passage of time. The Greco-Roman world devised an in-flow (rather than out-flow) method which, as water filled a container, would trigger a sound, creating an "alarm clock." Water clocks evolved that used gears and escapement mechanisms to produce greater accuracy.

An escapement is a gear mechanism that ticks forward and back to cause another piece to advance. The illustration shows how this works in a pendulum clock, advancing the hands. The use of the escapement was crucial to the development of mechanical clocks, which started to appear in the 14th century in Europe. (Not in the 10th, built by Gerbert d'Aurillac.)

Let's not neglect candle clocks. A Chinese poem written in 520CE by You Joanfu mentions a clock marked so that it could be used while burning to measure the passage of night time. The Anglo-Saxons credit Alfred the Great with creating the candle clock. He used squat candles (<5" high) marked at 1" intervals to mark time.

The hourglass was also a common method of measuring time, the earliest depiction of which is in a 1338 painting by Ambrogio Lorenzetti.

The earliest mechanical clock, a clock that did not use water or sand or candles, that used a predictable motion due to the escapement and a pendulum, did not appear until the early 1300s. Norwich Cathedral had a tower clock constructed in the early 1320s. The first known municipal clock that struck on the hours was in Milan in 1336. Over the next few decades, mechanical clocks appeared all over: Old St. Paul's Cathedral, Salisbury Cathedral (still has many original parts!), Wells Cathedral (still with its original face), etc. Detailed descriptions of clock designs by Richard of Wallingford (1292 - 1336) and Giovanni de Dondi (c.1330 - 1338) still exist, though the many clocks they built are long gone.

A king who developed his own timepieces made from candles? He sounds like someone worth looking into.

Who Invented the Mechanical Clock?

In researching the previous post, I came across a reference to Pope Sylvester II (formerly Gerbert d'Aurillac, c.946 - 1003) inventing the mechanical clock. The source of this was the William Godwin's final book, Lives of the Necromancers, An Account of the Most Eminent Persons in Successive Ages Who Have Claimed for Themselves, or to Whom Has Been Imputed by Others, The Exercise of Magical Powers [1834]:

This generous adventurer, prompted by an insatiable thirst for information, is said to have secretly withdrawn himself from his monastery of Fleury in Burgundy, and to have spent several years among the Saracens of Cordova. Here be acquired a knowledge of the language and learning of the Arabians, particularly of their astronomy, geometry and arithmetic; and he is understood to have been the first that imparted to the north and west of Europe a knowledge of the Arabic numerals, a science which at first sight might be despised for its simplicity, but which in its consequences is no inconsiderable instrument in subtilising the powers of human intellect. He likewise introduced the use of clocks. He is also represented to have made an extraordinary proficiency in the art of magic; and among other things...

The italics are mine. A little further along, Godwin adds a footnote that tells us his information comes from William of Malmesbury. William (c.1095 - c.1143) was the foremost English historian of the 12th century. Not exactly a contemporary, but maybe near enough that the memories and stories were still fresh? It would be difficult to determine the accuracy of this report, especially in the context of a brief blog post. Fortunately, I don't have to.

As it turns out, Marek Otisk of the University of Ostrava (Czechoslovakia) published an article on this very topic in September 2020, Gerbert of Aurillac (Pope Sylvester II) as a Clockmaker. He examines the reports from William of Malmesbury, the Chronicle of Thietmar of Merseburg (died c.1018), and a much later record (someone who died in 1610). Among his detailed examination of these and other historical records we learn that although William claims Gerbert built a clock in Reims, a friend of Gerbert's (Richest of Reims), writes about Gerbert's stay in Reims in detail and never mentions a clock. Otisk concludes that William's ascribing of the creation of a clock to Gerbert cannot be trusted.

The later report by the Benedictine monk Arnold Wion, who died about 1610, claims Gerbert built a clepsydra, a water clock, in Ravenna. What we know of Gerber's time in Ravenna, however, is that it was very short; again, no contemporary accounts support this story.

Thietmar of Merseburg tells a different story, that Gerbert created a clock in Magdeburg. Thietmar was a bishop and close friend of Holy Roman Emperor Henry II, who succeeded Otto III, credited with making Gerbert into Pope Sylvester II. Thietmar's Chronicle includes a specific detail about Gerbert creating, in Magdeburg, "created clocks (horologium) which he correctly calibrated according to the Polar star (stella, dux nautarum) which he observed through an observation tube (fistula)." [Otisk, p.32] Otisk likes this account because both Thietmar and Gerbert were in Magdeburg in the late 990s, and very likely crossed paths several times.

The use of the word horologium is misleading, however. We use it for the word "clock," but it is more likely that Gerbert was creating a calibrated armillary, or possible even an astrolabe, which he knew about from his exposure to science being done by Islamic philosophers.

So I can't tell you who created the first mechanical clock. But the question of horologium remains: when long-ago writers refer to "clocks," what exactly did they mean? What constituted a clock? There were several ways to measure time without staring at the sun and judging, and I'll talk about those devices tomorrow.

Armillary Spheres

The "wooden terrestrial spheres" mentioned here are what we now call "armillary spheres." An armillary is a spherical arrangement of rings designed to mimic the orbits of the sun and planets around the Earth—or around the Sun, depending on the prevailing theory at the time. If the Earth is the center, it is a Ptolemaic sphere; if the Sun is at the center, it is a Copernican sphere. China and Greece each invented them BCE. Hipparchus credited Eratosthenes (276 - 194BCE) as the inventor.

An early Christian philosopher, John Philoponus, wrote the earliest extant treatise on the armillary sphere and the astrolabe. The oldest example of one we have today dates to the 11th century.

Gerbert d'Aurillac (946 - 1003), who became Pope Sylvester II in 999, had brought the armillary sphere to Western Europe. He was also responsible for introducing Western Europe to the abacus, the Hindu-Arabic numeral system we use today, and (possibly) the mechanical clock.

Sylvester used the armillary sphere and sighting tubes to determine the definitive position of the pole star and to record measurements for the tropics and the equator. His work was improved upon in the Renaissance by Tycho Brahe (1546 - 1601). Public figures would have an armillary sphere incorporated into their portraits to indicate their wisdom and knowledge.

I've written about clocks before, but I don't recall learning that Gerbert d'Aurillac invented it. I want to check that out; I'll let you know what I find.

The Ottonian Renaissance

Although we use the term "renaissance" to refer primarily to a rebirth of art and culture that started in 14th century Italy and spread throughout Europe, the truth is that there were several rebirths of culture between the Fall of Rome and the 14th century. I discussed this a decade ago here. One such rebirth took place during the Ottonians in Germany in the 10th century.

Part of this was not so much a rebirth as an influx of culture from the east: the Byzantine Empire maintained some of what Western Europe "lost" during those centuries. When Otto I married his son, Otto II, to Theophanu, the daughter of the Byzantine Emperor John I Tzimiskes, he opened the door to Byzantine art and increased commerce. Another important figure involved was Gerbert of Aurillac, who became Pope Sylvester II during the reign of Otto III.

Sylvester II introduced the abacus for computation, and wooden terrestrial spheres for the study of the movement of planets and constellations. He composed De rationalis et ratione uti (Of the rational and the use of reason) and dedicated it to Otto III. Promoting reason over faith was an important step in the study of the sciences. Sylvester also promoted the expansion of abbey libraries, particularly at Bobbio Abbey (where St. Columbanus wound up earlier), which had almost 600 works.

Arts and architecture also stand out in an examination of the Ottonian Renaissance. The revival of the Holy Roman Empire brought inspiration to think on a grander scale and create art and buildings that reflected the grandeur to which the Ottonians believed they were heir. Large bronze doors on churches and gilded crosses became more common. Ottonian patronage of monasteries produced grand illuminated manuscripts. One of the most famous scriptoria was Reichenau, which produced Hermann of Reichenau. This is also the period of the literary output of Hrotsvitha of Gandersheim.

A campaign of renovating churches and cathedrals also took place. (The illustration is an ivory plaque showing Otto I on the left, shown smaller than the saints, presenting Magdeburg Cathedral to Christ.) Longer naves and apses were inspired by Roman/Byzantine basilica. Many of these church designs and re-designs came form the hand of Otto I's brother, Bruno the Great. Bruno extended the cathedral in Cologne to rival the size of St. Peter's in Rome (Cologne Cathedral burned down in 1248, alas). He also built a church dedicated to St. Martin of Tours.

Ivory carving and cloisonné enamels were also widely produced in this era. A major workshop for cloisonné enamels was established by Archbishop Egbert of Trier, using a Byzantine technique of "sunken" enamel, where thin gold wire was soldered to a base, and colored glass melted into the spaces, as opposed to the original style of affixing gemstones as an inlay.

I find Ottonian art, though lovely, does not tickle my interest as much as those "wooden terrestrial spheres" of Pope Sylvester, so I'm going to look into those for next time.

The Ottonians

The Ottonians, the Ottonian dynasty, the Ottonian Period in Germany—all these refer to the same topic: a Saxon dynasty of German monarchs (three of whom were named, natürlich, "Otto") that lasted from 919 until 1024CE.

Its founder was not named Otto, however (although his father was); that was Henry the Fowler (876 - 936), son of Otto the Illustrious. He was named primus inter pares (Latin: "first among equals") by the German dukes of Bavaria, Swabia, and Lotharingia during the Hungarian invasions of East Francia, and named Rex Francorum ("King of the Franks") in 919. He was victorious over the Hungarians and amassed sufficient power to be uncontested when he passed his title onto his son, Otto I (912 - 973).

Also known as Otto the Great, one of the chief historical events connected to him is the restoration of the Holy Roman Empire (which, it should be noted, was by any standard definitions neither "holy" nor "Roman" nor an "empire"). Sure, the administrative structure needed to manage the large area (shown in the illustration) was inherited from the Carolingians and Charlemagne, and they got it from the Romans, but it was nowhere near what the Roman Empire had been.

Pope John XXII, however, wanted Otto's help in controlling Rome and the Lombards. Otto was a good choice: he was geographically close to Rome, he had defeated the pagan Magyars in 955, making him look like a hero for Christianity, and he was (in some ways) the successor of a previous Frankish king, Charlemagne, who had been made Holy Roman Emperor in Christmas Day in 800. Otto, whose wife was the Italian Adelaide of Burgundy (931 - 999). stepped in for the pope and conquered the Kingdom of Italy in 961. He was crowned Holy Roman Emperor on 2 February 962.

The "re-creation" of the empire and its expansion to much of central and Southern Europe sparked a bit of a cultural resurgence, the Ottonian Renaissance. This continued under Otto the Great's son, Otto II, partially because of his marriage to Theophanu, the niece of Byzantine emperor John I Tzimiskes. This helped create an influx of Byzantine art into Europe.

Otto II died after only 10 years, aged 28. His son, Otto III, was only 3 years old; his regents were his mother Theophanu, his grandmother Adelaide, and Henry II ("the Quarrelsome"), Duke of Bavaria. When he came of age, among other things he installed his confidants as popes: Pope Gregory V and the science-minded Gerbert of Aurillac, Pope Sylvester II.

When Otto III  died young (aged 21 years), he was succeeded by Henry II, a son of his regent Duke Henry. Henry was crowned emperor by Pope Benedict VIII in 1014. He founded numerous dioceses and intertwined secular and religious administrative power. When he died childless in 1024, the Ottonian dynasty ended. The crown went to Conrad II, a great-grandson of a daughter of Otto I, starting the Salian dynasty.

Before we can move to other topics, however, I want to look more at the results of the Ottonian Renaissance. See you tomorrow.

Medieval Feminism

It is not fair to suggest that there was a "feminist movement" in the Middle Ages, but there were many examples of women who did not conform to what the Modern Age thinks of women in the Middle Ages being forced into "traditional" roles. Hrotsvitha of Gandersheim was one of those examples.

Hrotsvitha was a 10th century nun in the Abbey of Gandersheim who turned her hand to writing poetry, plays, and histories. The illustration, a woodcut by Albrecht Durer, shows her presenting her history of the Ottonian Empire to Otto the Great (he was previously mentioned here and here). As the first to write dramas in the Latin West, as the first female German poet, she became revered as a feminist icon in the 1970s.

Although she writes that any excellence in her work comes from God, not from her, she was not saying that she, as a woman, had no ability to produce excellence. This may have been just a literary convention, or even true humility. In fact, she sees that women taking the veil and taking vows of chastity shows the power of self-determination, rejecting the role of wife and mother that men would put them in.

Encouraged to write plays after reading the Roman playwright Terence, she produced works with female characters very different from his shrews and courtesans. Her female characters are virtuous, courageous, witty, and close to God. Even though she saw women as somehow weaker than men in worldly terms, she considered women more suitable instruments for God to bring about grace and salvation for them and those around them. She saw men as more susceptible to temptation and sin.

Her plays dealt with subjects important to women: marriage, rape, objectification. In Callimach, a man attempts to rape a beautiful woman, who prays for death. This she is granted by God before she can be violated. When the rapist resumes with her corpse, he is bit by a venomous serpent and dies. Dulcitius, aka Passio Sanctarum Virginum Agapis Chioniae Et Hirenae ("The Passion of the Holy Virgins Agape, Chionia, and Irena"), shows how a governor, Dulcitius, is foiled in his passion by three virgins. (You can read the play yourself here. It has fewer than 300 lines!)

Hrotsvitha clearly believed in an ideal of the virginal woman, which some dismiss as merely a Christian construct which prevents women from aspiring to higher goals, but it is argued that she was promoting a model of female integrity that encouraged more positive views of women in 10th century Germany.

Hrotsvitha was alive during the Ottonian Period in Germany, which I have barely touched on all these years. Let's get a better idea of what it was next time.

Hrotsvitha of Gandersheim

A nun, a poet, a playwright— Hrotsvitha of Gandersheim has been called the most remarkable woman of her time, but she was hardly known until a manuscript of her works was discovered in 1494.

From information in her writing we can glean that she was born between 930 and 940CE to a well-to-do Saxon family. We do not know what prompted her to "take the veil" and enter a nunnery, but we know she took vows of chastity and obedience but not poverty, presumable because she did not want to give up comforts and freedoms she had grown up with.

In a preface to her poetical works, she writes of her education at the Abbey of Gandersheim:

I was trained first by our most learned and gentle novice-mistress Rikkarda and others. Later, I owed much to the kind favour and encouragement of a royal personage, Gerberga, under whose abbatial rule I am now living. She, though younger in years than I, was, as might be expected of the niece of an Emperor, far older in learning, and she had the kindness to make me familiar with the works of some of those authors in whose writings she had been instructed by learned men.

Among the works to which she was introduced were those of the Roman playwright Terence, and she decided she wanted to try her hand at that genre, making her the earliest known playwright—female or male—in the Latin West. Where Terence wrote women as shrews and courtesans, Hrotsvitha wrote them as innocents who were exemplars of Christian virtue.

She was the first female poet in Germany, writing several works in dactylic hexameter, including a history of the Ottoman Empire. and a history of Gandersheim Abbey.

She was the first Northern European to write about Islam. In her play Passio Sancti Pelagio ("The Passion of Saint Pelagius"), which she says is derived from an eyewitness to the martyrdom of Pelagius of Cordova, she refers to the character of Abd al-Rahman III, the Emir of Cordova from 929-961. Her plays read as dialogues, which means they are labeled "closet dramas" (a play meant to be read out loud, rather than performed). We know, however, that the Abbey enjoyed her writing, and she was asked to read to the other nuns, so it is possible that her plays were "performed" at Gandersheim.

The discovery and publication (in 1501) of her works made her a subject for study. In the 20th century, she became a feminist icon, which means I'll take a deeper dive into her works tomorrow.

Theophilus the Penitent

Let me tell you about Theophilus the Penitent, a Christian cleric who was the archdeacon of Adana in Cilicia (now Turkey). He was known for being generous to the poor, eloquent when preaching, sympathetic to others, and for his asceticism. When the bishop died, Theophilus was offered the position, and was very strongly urged by all to take it.

Out of humility, he refused the position, presumably with the standard Latin phrase nolo episcopari, "I do not wish to be made bishop." (It is traditional that the candidate say this at least twice when offered a bishopric before finally accepting; if he says it a third time, he really means to refuse the promotion.)

Unfortunately for him, some people decided to malign him, spreading rumors that turned the populace against him and so unnerved him that he started spending all his energy in combatting the four rumors being spread, and attempting to find the sources of the rumors. The current bishop, hearing the rumors against him, fired him from his archdeacon position.

Finally, Theophilus appealed to a necromancer for help, who led him to a crossroads in the dark of the night and conjured up Satan. Satan offered a deal: in exchange for his soul, all calumnies against him would disappear. Theophilus agreed, and signed a contract with his own blood. The next day, he was summoned to the bishop's presence; the bishop had discovered that the rumors were false, Theophilus was a good man after all, and the bishop re-instated him in his position.

But Theophilus had no peace of mind. He paced his room night after night, regretting the foul bargain he had made, and he prayed. He undertook a fast of 40 days, praying every night, all night, until the 40th day when the Virgin Mary appeared to him. She rebuked him for his poor decision, and he asked her to intercede for him. This she agreed to do, and the following night she appeared in his dream and told him that her son had forgiven him. When he woke up the next morning, the static contract was with him.

That day being Sunday, he went to church, threw himself at the feet of the bishop to make his confession, and showed the congregation the contract. They destroyed the contract, Theophilus went home feeling unburdened...and died three days later.

People love a comeback story, and sinners repenting. Theophilus became the subject of poems and plays as well as sermons. The earliest version of the story claims to come from Eutychianus, a disciple of Theophilus who was an eyewitness. (The only Eutychianus who makes it into Christian records is a 3rd-century pope.) Legend tells us that Theophilus died in 538CE. There is a Latin version of the story (the original is Greek) from Paulus Diaconus.

It is in the 11th century that art depicting his story first appears, in carvings, but it really takes off in the 13th century in stained glass windows and illuminations. Above is supposed to be Theophilus building a church in his capacity as archdeacon. The usual portrayal is in four panes: signing the contract, Theophilus repenting, the Virgin recovering the contract from the devil, the Virgin returning the contract to Theophilus. Other than the Theophilus story, all examples of Marian art in churches and cathedrals are Bible stories.

One of the better-known composers of Theophilus-based poetry was Hrotsvitha of Gandersheim, a name that is so familiar to me that I'm shocked to find that I have never mentioned her before in this forum. I aim to correct that defect tomorrow.

Making Stained Glass Windows

Creating sufficiently high temperatures needed to melt silica and fashion glass was difficult, but at some point we discovered that the addition of potash (potassium, from wood ash soaked in water), soda (sodium carbonate, from plant ash), and lead would lower the melting point, making production easier.

Now you have molten glass; how do you shape it?

The oldest stained glass windows were made from "muff" glass: a blob of molten glass, called a "gather," was placed on the end of the blowpipe. Using metal tools and wooden forms soaked in water, the glass was blown into a cylinder. The ends of the cylinder would be cut off, and the cylinder cut open so it could be flattened.

"Crown" glass (see illustration) started similarly with a gather of glass on the blowpipe; after introducing a bubble of air, the pipe would be spun back and forth quickly, causing the glass to spread out into a thin disk. This could also be accomplished by placing the molten glass on a contraption like a potter's wheel. The circle of glass could be cut to fit into square windows, or used round. Crown glass windows are recognizable because of the concentric circles formed during the spinning. They usually also have a "bull's-eye": the thicker blob at the center of the spun circle.

You may hear of "cathedral glass." This is rolled glass: molten glass poured onto a metal table and rolled thin with a metal roller. It was sometimes even put through a pair of rollers. This technique has nothing to do with medieval cathedrals, having been developed in the mid-1830s.

Coloring the glass was done by adding copper oxide (green or bluish green), cobalt (deep blue), or gold (wine red and violet). (Modern glass produces red using copper.)

For stained glass windows to survive wind pressure, it needed to be at least 3mm (1/8") thick. The production of red required a concentration of added material such that a 3mm window had so much coloring that the red was very dark; it could be mistaken for black without a very strong light source. This prompted the development of "flashed glass": adhering a thin pane of red to a thicker pane of clear.

Before we leave the subject of old windows, I want to tackle a common talking point that I have heard many times: "Glass is a liquid that flows very slowly; the proof is that medieval windows are thicker on the bottom than the top!" Sure, maybe. But let's remember Occam's Razor: common sense would tell the architect that a pane of glass that is not of even thickness—not an unexpected outcome considering the imprecise methods of manufacture—would be more stable if you put the heavier end as the base.

Being able to color panes and pieces of glass allowed creators of windows to offer elaborate pictures, such as stories from the Bible or history. Tomorrow I'll share a story of Theophilus, who was a common theme for church windows in the 13th century.

Stained Glass

The art of coloring glass was evident in articles from ancient Egypt and Classical Rome. "Stained glass" can mean any glass that is colored, by either adding particle or chemicals to the glass during production or by painting the glass later, but I am going to talk specifically about windows.

There are some very early (4th- and 5th-century) Christian churches that have, not stained glass, but carefully carved thin slices of alabaster—a precursor to the elaborate stained glass windows of the Middle Ages.

Our earliest references to stained glass for religious purposes in medieval Europe comes from Benedict Biscop, who hired glass workers from France to create windows for his monastery at Monkwearmouth. Here and at his other monastery at Jarrow have been found hundreds of pieces of colored glass and lead (used to hold the glass together). These were constructed in the 7th century. The 10th century saw church windows in Germany, France, and England depicting scenes from the Bible.

I talked about Abbot Suger long ago, who re-built the Abbey of St.-Denis with special attention to the stained glass windows. He wrote down his thoughts and reasoning (and justification for spending an enormous sum of money on the renovations):

All you who seek to honor these doors,
Marvel not at the gold and expense but at the craftsmanship of the work.
The noble work is bright, but, being nobly bright, the work
Should brighten the minds, allowing them to travel through the lights.
To the true light, where Christ is the true door.
The golden door defines how it is imminent in these things.
The dull mind rises to the truth through material things,
And is resurrected from its former submersion when the light is seen.

Suger considered the beautiful windows to have an ennobling effect on the viewer, which was no doubt advantageous for making an impression on the congregation.

Glass-making takes a lot of heat, expertise, and knowledge of rudimentary chemistry to color the glass. What was that about? That is our next topic.

Medieval Paints and Pigments

Where did medieval manuscript illuminators get their colors?

Well, first thing to realize is that they weren't re-inventing the wheel: Romans had colored paints available to them. The Romans used the term minium to refer to pigment from ground cinnabar (brick-red mercury sulfide) or red lead (lead oxide). Some minerals that were dug up and ground included:

red ochre — iron oxide/hematite (rust color)
yellow ochre — silica and clay/iron oxyhydroxides (shades from cream to brown)
umber — iron and manganese oxides (from cream to brown)
lime white — dried lime/chalk (white)
green earth (Verona green) — celadonite/glauconite (green)
azurite — carbonate of copper (blue)
ultramarine — lapis lazuli (blue)

Pigments could also be made from plants. Red could be made from the root of the Eurasian madder plant. The Crozophora plant's seeds produced a violet-blue. Saffron gave yellow. Woad and indigo came from plants that carried the same name. Let's not forget insects, that could be crushed to give the bright-red carmine (from the cochineal or Dactylopius coccus scale insect). 

Preparation of paints was a careful process. The coloring was usually mixed gum arabic or with egg. Egg tempera (from the yolk) or egg glair (from the white) were ways to "fix" the pigment to the surface you were using. Because the egg tempera could crack, it was applied in paintings in thin layers.

Some colors were more special than others. Ultramarine (literally "beyond the sea"), the blue made from grinding lapis lazuli, came from Afghanistan and was very expensive to obtain. This brightest blue, however, was associated with the gown of Mary, the mother of Jesus, so it was greatly desired and worth the price.

Another questio0n regarding color in the Middle Ages comes to mind, however. How did they get the color into glass? That's for next time.

Masters of Marginalia

Marginalia—comments, doodles, annotations, etc., made in the margin of a manuscript or book—came in many forms. Here we talked about the attempts at educating and clarifying by scholiasts.

Today we look at the less serious additions made by monks who were no doubt bored and decided to exercise their sense of humor.

There are so many web pages where you can find more in varying stages of frivolity and obscenity if you simply search "medieval marginalia" the you can send days of diversion that it would be pointless for me to try to give you more than just a bare minimum of representative figures.

These marginalia don't make much sense, in that they don't generally have anything to do with the text they accompany except in the most tenuous way. For instance, the bottom illustration in the collection I have included shows a fox as a bishop preaching to a flock of different birds, which would normally be his prey. Commentary by a monk on what he really thinks about bishops and their attitude toward their congregations? Or just an attempt at an ironic drawing of animals?

Snails actually show up frequently, often involving combat. The top right shows a snail with an animal's head. Below that is a snail fighting a knight. There is conjecture that the shell of the snail, since it resembled a kind of armor, was an appropriate foe for a knight.

Some additions are attractive additions, like the unicorn, although right above it is a curious animal-headed set of tentacles or vines. I would call that simply a doodle.

Then you have pictures that are far more irreverent than a fox preaching to birds, such as the monk sniffing the butt of an ... animal? Demon? Hard to say what it is in that top-left illustration. At least it is very attractively enclosed in the curves and points of its surrounding frame.

We should note that the making of marginalia was not that impulsive; that is, the manuscript copyist did not say to himself "I'll just out a goose playing a lute here." These were added by someone who was sitting with access to multiple colors of ink in front of him. He was the monk tasked with "prettying up" the manuscript in order to make it more valuable and less likely to bore the reader. Hundreds of years later, these colors remain on the vellum, which has got me thinking: where did colored inks/paints come from in the Middle Ages?

I will look into that question, and get back to you. See you tomorrow.