Boys have a very curious saying respecting the reflection of the sun's
beams from the surface of water upon a ceiling, which they call
"Jack-a-dandy beating his wife with a stick of silver." If a mischievous
boy with a bit of looking-glass, or similar material, threw the
reflection into the eye of a neighbour, the latter would complain, "He's
throwing Jack-a-dandy in my eyes."