Nearly every empire worthy of the name--from ancient Rome to the United States--has sought an Egyptian obelisk to place in the center of a ceremonial space. Obelisks--giant standing stones, invented in Ancient Egypt as sacred objects--serve no practical purpose. For much of their history their inscr[...]

In the decades around 1900, postcards were Twitter, email, Flickr and Facebook, all wrapped into one. A postcard craze swept the world, and billions of cards were bought, mailed and pasted into albums. Many famous artists turned to the new medium, but one of the great pleasures and enigmas of postca[...]