This instrument is known both as a “glass harmonica” and a “glass armonica,” and I personally favor the latter spelling to distinguish it from the better-known free-reed mouth harp also called a “harmonica.” The tone of a glass armonica is stunningly beautiful; a great 18th-century myth is that the purity of its sound will eventually drive a virtuoso to madness. Thomas Bloch’s website has more info about his work and about the particular custom-built instrument shown here. [via Neatorama]