|C. Allen Gilbert, All Is Vanity|
Gilbert's skull illusion is skillfully made and undoubtedly deserving of its popularity. But it is somewhat less than original. Throughout history, there have been repeated attempts at designing scenes of daily life that, from a distance, change into icons of death. Below is an example of one made by a German artist in 1866, in which two young people take on the shape of a skull when viewed from a distance. When translated, the label beneath the image reads "blood and decay." The Spanish surrealist Salvador Dali alluded to the same symbolism when he devised a "double image" (in a 1940 painting called Slave Market with the Disappearing Bust of Voltaire) that at first appears to be a bust of the French philosopher Voltaire, and then, at other times, perhaps an image of two nuns.
|Anon, Blood and Decay|
And at last, below is another example, also German, from the 19th century.