Is this art? It’s a drawing made by Austrian scholar and mystic Rudolf Steiner, who traveled Europe between 1919 and 1924 giving more than 5,000 lectures on “spiritual science,” art, medicine, agriculture, and economics. During the lectures Steiner would draw on the blackboard, and in 1919 his colleague Emma Stolle, apparently realizing the drawings’ value, began placing sheets of black paper over the blackboards in order to capture them.

Steiner himself doesn’t seem to have intended the drawings as beautiful, only as vehicles to express his ideas. Here’s the point he was illustrating with the image above, from a lecture on Aug. 12, 1924:

You look at a plant and say to yourself: I am a being of which I see only a mirror image, an inessential reflection, while on Earth. The more I turn my gaze to the stars, the more I see the true being up there. Nature is revealed in its entirety only when I look up from the Earth to the stars, when I consider the Earth and the cosmos as one. Then I can look back to myself as a human being and say: that which in the plant reaches up to the heavens has been compressed (bunched together) into myself on Earth. As a human being, I carry the physical world, the soul world, and the spiritual world.

Piet Mondrian, Wassily Kandinsky, and Alexej von Jawlensky all attended Steiner’s lectures, though none of them left any written comment about the images he drew. But one museum director remarked that if Steiner’s drawings don’t fit within any current definition of art, then a definition must be devised to include them.

(Lawrence Rinder, ed., Knowledge of Higher Worlds: Rudolf Steiner’s Blackboard Drawings, 1997.)

Prague artist Robert Barta’s installation Crossing Half a Million Stars consists of 500,000 ball bearings covering the floor of a room.

The visitors themselves create a spontaneous performance as they try to make their way across it.

Typographer John Langdon created this pleasingly ornate ambigram in 2005. It reads the same upside down.

More at his site.

Here’s one way to end a composition: Johann Jakob Froberger’s Suite II in C major, Lamento sopra la dolorosa perdita della Real Msta di Ferdinando IV, Re de Romani, ends with a picture of the clouds of heaven welcoming the soul of Ferdinand IV as it climbs up a scale of three octaves.

It was written to lament the death of the King of the Romans in 1654. Elsewhere Froberger had marked the fatal fall of lutenist Charles Fleury down a flight of stairs with a descending scale of two octaves. Perhaps he was just very literal-minded.

(From Wilfrid Hodges, “The Geometry of Music,” in John Fauvel et al., Music and Mathematics, 2006.)

Conservators at the National Galleries of Scotland have discovered “what is almost certainly a previously unknown self-portrait by Vincent van Gogh.”

The image emerged in an x-ray of the artist’s 1885 painting Head of a Peasant Woman, taken in preparation for an upcoming exhibition. To save money, van Gogh sometimes used both sides of a canvas; in this case the reverse image had been hidden by layers of glue and cardboard that were applied before an exhibition in the early 20th century. It’s not yet clear whether these layers can be removed without harming Head of a Peasant Woman.

This isn’t the first time a “lost” image has been discovered in a van Gogh painting. In 2008, x-rays revealed the portrait of a woman behind the artist’s 1887 painting Patch of Grass — apparently he had painted over an image he’d completed two years earlier.

This is a miniature, a tiny replica of an English dining room of the late 18th century. Between 1932 and 1940, American artist Narcissa Niblack Thorne made about 100 such diminutive rooms, often enlisting architects, designers, and craftsmen whose talents became available during the Depression.

Of the miniatures still in existence, most are on display at the Art Institute of Chicago, where they serve as documents of the decorating styles of periods past. Generally designed on a scale of one inch per foot, many of them include authentic materials: bowls of real silver, chandeliers of real crystal, even original paintings and sculpture contributed by admired artists.

In 2010, the institute began to decorate them for the holidays each year, after researchers discovered Thorne’s affection for Christmas. But “Some of the rooms will never have a holiday theme,” the museum’s Lindsey Mican Morgan told the Chicago Tribune. “That is because many of them depict a room from a time when holidays were simply not celebrated as they are now.”