Extreme Weather

"Volcanic winter" is a frightening phrase. It is the result of a volcanic eruption that spews so much ash and dust into the atmosphere that it encircles the globe and prevents sunlight from reaching the surface of the Earth. 

A volcanic winter took place in the 530s CE, the most severe drop in temperature in the Common Era. An eruption of sulfate aerosols possibly in late 535 dropped summer temperature averages in 536 by at least 4-5 degrees Fahrenheit. In 539-540, a second volcanic eruption caused summer temperatures to drop another 5 degrees.

This was recorded in the Northern Hemisphere by contemporary writers in Constantinople. Procopius, whose writing revealed the secret of where silk came from, records of 536 

...during this year a most dread portent took place. For the sun gave forth its light without brightness … and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear."

Cassiodorus, in a letter in 538, describes the sun's rays being weak, no shadows from people at noon, the sun's heat being feeble, the moon "empty of splendor," prolonged frost, unseasonable drought, frosts during harvest, the need to use stored food because harvests were so poor.

The Annals of Ulster mention a failure of bread in the year 536.

Dendrochronology (tree ring analysis) shows very poor growth in Irish oak in 536. Ice cores from Greenland and Antarctica show substantial sulfate deposits around 534±2 years, which offers evidence for the volcanic eruption. Which volcano was the cause, however, has never been agreed upon. The 536 event was worse than 1816, when the explosion of the Mount Tambora volcano caused the "Year Without a Summer."

As mentioned in the prior post, the line regarding the Battle of Camlann in the Welsh Annals that says of 537 "there was great mortality in Britain and Ireland" is likely a reference to the famine that resulted from the volcanic winter.

The 536 event was not the only severe weather crisis in the Middle Ages. Next time, let's jump forward to the Great Famine of 1315-17.

Cassiodorus and Colleges

Yesterday's post mentioned Cassiodorus (c.485-c.585), a contemporary of Boethius, and his description of the relationship between Arithmetic and Music. His full name was Flavius Magnus Aurelius Cassiodorus Senator. He was not a senator; that was part of his name, although he was a statesman under Theoderic the Great, king of the Ostrogoths.

He served in several different roles in government, and his literary skills were so well recognized that he was often asked to draft important documents while he was in Ravenna. (Why Ravenna and not Rome? That is for the next post.) Whether because he was a devoted statesman, or just because of personal inclinations, his writings try to unite the cultural differences between the Eastern and Western Roman empires, between Greek and Roman cultures, between the Roman culture and the invading Goths, and even between established Christian doctrine and heresies. After his retirement from public life, he founded a monastery and turned to writing about religion.

The immediate reason for bringing him up in a medieval blog, however, is his link to medieval universities, which didn't exist for several centuries after his death. We are familiar by now with the medieval curriculum of the trivium (Grammar, Rhetoric, Logic) and the Quadrivium (Arithmetic, Music, Geometry, Astronomy). You might be surprised to know that Cassiodorus not only listed these fields of study, in that order, but also that he derives them from the study of the Bible.

In his Expositio Psalmorum ["Explanation of the Psalms"], he interprets Psalm 18.5

"Their voice resounds through all the earth, and their words to the ends of the earth"

as the teachings of the Bible being spread throughout the world, and that these teachings are the origin of secular studies. Therefore, mastering the secular arts helps bring one back to better comprehension of the Bible. This was, in fact, considered the original purpose of medieval universities: to train better clerics.

The Philosophy of Music

Much of the medieval attitude about music and its forms came from Boethius (c.480-524 CE). In his de institution music [Latin: "On the laws of music"] he distinguished three types of music:

Instrumental music
Human music
Mundane music

Detail from copy of De musica [source]

Although today we use the word "mundane" to refer to something ordinary, it comes from Latin and refers to the world; Boethius uses it to refer to the music made by the world, that is, the so-called "music of the spheres": that sound, inaudible to human ears, that was made by the friction of the spheres surrounding the Earth in which the planets and other heavenly bodies traveled.

Instrumental music referred to music made by one of several different agents. It could come from something under tension (such as with stringed instruments), by wind, by water, or by percussion. It should be noted that Boethius was not referring to "musical instruments" as much as he used the term to mean that some physical agency was causing the sound. That could be a rushing stream, the wind in the trees, and falling rocks as much as manufactured devices in the hands of a musician. Later writers included singing as part of this category.

Human music was therefore not referring to singing by humans. For the Middle Ages, "music" was all about harmony, and the "harmony" between the physical body and the spiritual side was a serious topic. For example, you must nourish the physical body, but you must not eat so much that you fall into the sin of gluttony. Proper proportion was everything.

In fact, music (as opposed to mere noise) was all about harmony and proportion. That is why Music was studied in the medieval university only after mastering Arithmetic. A contemporary of Boethius, Cassiodorus (485-c.585 CE), compared the two by explaining that

Arithmetic is the discipline of absolute numerable quantity. Music is the discipline which treats of numbers in their relation to those things which are found in sound.