Carbuncle of Ward Hill
(The). A mysterious carbuncle visible enough to those who stand at the foot of the hill in May, June or July; but never beheld by anyone who has succeeded in reaching the hill top.
“I have distinguished, among the dark rocks, that wonderful carbuncle, which gleams ruddy as a furnace to them who view it from beneath, but has ever become invisible to him whose daring foot has scaled the precipice from which it darts its splendour.” —Sir W. Scott: The Pirate, chap. xix.
Dr. Wallace thinks it is water trickling from a rock, and reddened by the sun.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894