Researcher uncovers secrets of Kells 'angels'

September 2, 2009 By Lauren Gold
Researcher uncovers secrets of Kells 'angels'

Enlarge

Professor John Cisne looks at folio 85v in "The Book of Durrow," a manuscript with microscopically detailed illumination. Image: Lindsay France/University Photography

(PhysOrg.com) -- The Book of Kells and similarly illustrated manuscripts of seventh- and eighth-century England and Ireland are known for their entrancingly intricate artwork -- geometric designs so precise that in some places they contain lines less than half a millimeter apart and nearly perfectly reproduced in repeating patterns -- leading a later scholar to call them "works not of men, but of angels."

But behind the artwork's precision is a mystery: How did illustrators refine the details, which rival the precision of engravings on a modern dollar bill, centuries before microscope lenses were invented?

The answer, says Cornell paleontologist John Cisne, may be in the eyes of the creators. The Celtic monks evidently trained their eyes to cross above the plane of the manuscript so they could visually superimpose side-by-side elements of a replicated pattern, and thereby, create 3-D images that magnified differences between the patterns up to 30 times.

The monks could then refine any disparities by minimizing the apparent vertical depth of the images -- ultimately replicating the design element to submillimeter precision. Cisne proposed the idea in the July 17 issue of the journal Perception (Vol. 38, No. 7).

The paper suggests that the technique, called free-fusion stereocomparison, which takes advantage of the brain's ability to perceive depth by integrating the slightly different views from each eye, was known nearly a thousand years before it was articulated by stereoscope inventor Sir George Wheatstone in the 19th century.

Cisne analyzed the most detailed illuminated manuscripts of the Middle Ages, created between 670 and 800 A.D., including the Book of Kells (circa 800 A.D.); some have as many as 30 lines per centimeter.

Researcher uncovers secrets of Kells 'angels'
Enlarge

Detail of folio 85v of "The Book of Durrow"

The artists stayed mum about their techniques, possibly because their talent gave their Celtic church an edge over the Roman church in the competition for disciples. "If you're in the middle of a propaganda war, [it helps] if the angels are clearly on your side," Cisne said.

But they left a few clues, he said, including the high degree of symmetry and repetition among many of the most intricate patterns and the elements' spacing, which is usually at about the distance between an average person's pupils.

"It turns out that if you can draw accurately enough, you can easily get a magnification of the lateral [horizontal] distance something like 10, 20 or 30 times -- about the magnification you could get under a dissecting microscope," Cisne said.

The monks likely created a highly accurate template for the design elements by drawing the same element repeatedly, comparing versions and modifying to create a standardized model. From there, they could replicate it into complex designs, using free-fusion stereoscopic comparison and minimizing errors along the way.

Many of the design elements contain minute imperfections that are consistent throughout rows or columns, supporting the idea that the monks worked from templates. And depictions of scribes from the era often show the monks holding pen in one hand and erasing knife in the other -- another clue that they made modifications along the way.

"The idea is that these guys did it just the same way I do when I use a drawing tube and a microscope -- lay down a reference grid, fill in the details, and then compare the details with your template," Cisne said.

Their knowledge of stereoscopic imagery likely died with the monasteries, which were later decimated by the Vikings, Cisne said. The original manuscripts are in Dublin and London; Cisne worked from high-quality reproductions in Cornell's Division of Rare and Manuscript Collections in Kroch Library. They're a reminder, Cisne said, that ingenuity can sometimes trump technology.

"Most people don't appreciate what a fine instrument they have in their eyes," he said, "and how their visual system can be used in other than the obvious ways."

Provided by Cornell University (news : web)

4.9 /5 (21 votes)  

Filter


Move the slider to adjust rank threshold, so that you can hide some of the comments.


Display comments: newest first

Sean_W
Sep 02, 2009

Rank: 5 / 5 (1)
"Kells angels". I am embarrassed to admit it but I found that very humorous.

I'm a secular fellow but I have to hand it to those monks. Clever bit thing that. And it's interesting that the researchers can figure this out.
docknowledge
Sep 02, 2009

Rank: 3 / 5 (2)
Very interesting piece of speculation.

Also interesting, if true, how basic human functions can remain unknown for centuries to the general population.
russcelt
Sep 03, 2009

Rank: 4 / 5 (1)
Shows the tragedy and unintended consequences of climate change. The Celts explored the frontier of humanity on many levels. Their greatest failing was on being followed by an even bigger and more ruthless wave of humanity.
googleplex
Sep 03, 2009

Rank: not rated yet
I think this is the same effect as those 3D posters and books I have seen. The key is keep your eyes about 6 inches from the text and pull focus on your eyes to long distance. Then a 3D image appears.
Somehow the monks must have experimented with the concept to produce the magnification method.
Perhaps the monks eyesight got ruined which gave the vikings another advantage?!
Rank 4.9 /5 (21 votes)
Relevant PhysicsForums posts

More news stories

US workers are 'giving away the store,' costing firms billions

Nearly 70 percent of the nation's service employees give away free goods and services – from hamburgers to cable TV – costing companies billions of dollars a year, according to a groundbreaking study.

Other Sciences / Economics & Business

created 15 hours ago | popularity 5 / 5 (1) | comments 8

Storm warning: Financial tsunami heading this way

In today's global village, national coffers are more interconnected than ever before. And as the current economic crisis has proven, a downturn in one country can travel in a wave across the globe, like a financial tsunami. ...

Other Sciences / Economics & Business

created 16 hours ago | popularity 3 / 5 (2) | comments 7

Kids show cultural gender bias

(PhysOrg.com) -- Talk about gender confusion! A recent study by University of Alberta researchers Elena Nicoladis and Cassandra Foursha-Stevenson in the Journal of Cross-Cultural Psychology into whether speaki ...

Other Sciences / Social Sciences

created 21 hours ago | popularity 1.5 / 5 (2) | comments 2

Prague gets hold of modern genetics founder Mendel's papers

Germany has handed to the Czech Republic a manuscript of Johann Gregor Mendel, founder of modern genetics, on his plant hybridization experiments, the Czech foreign minister said Thursday.

Other Sciences / Other

created 12 hours ago | popularity 5 / 5 (1) | comments 1

'Flipped classroom' teaching model gains an online community

Researchers at Harvard University have launched the Peer Instruction (PI) Network, a new global social network for users of interactive teaching methods.

Other Sciences / Social Sciences

created 16 hours ago | popularity 5 / 5 (2) | comments 0


Humans may have helped the decline of African rainforests 3000 years ago

(PhysOrg.com) -- Large areas of rainforests in Central Africa mysteriously disappeared over three thousand years ago, to be replaced by savannas. The prevailing theory has been that the cause was a change ...

Japan scientist makes 'Avatar' robot

A Japanese-developed robot that mimics the movements of its human controller is bringing the Hollywood blockbuster "Avatar" one step closer to reality.

Fighting crimes against biodiversity: How to catch a killer weed

Invasive species which have the potential to destroy biodiversity and influence global change could be tracked and controlled in the same way as wanted criminals, according to new research from Queen Mary, University of London.

Metastatic breast cancer hitches a free ride from the immune system

Inflammatory breast cancer (IBC) is the most lethal form of breast cancer . It spreads easily through the lymphatic and blood vessels, forming metastasis which can lead to multi-organ failure. New research published in BioMed ...

A novel method for simultaneously measuring blood pressure and arterial stiffness

Arterial stiffness due to is a major contributor to cardiovascular disease but is very difficult to measure. It also can influence blood pressure readings since these rely on the time taken for arteries to return to normal ...

India's global pharmacy role threatened by EU pact

(AP) -- Efforts by India and the European Union to strengthen trade are threatening India's ability to deliver lifesaving medicines to the world's poorest, analysts say as the two sides push through protracted ...