SHADOW IMAGE OF MOUNT .ETNA. 215 



the theatre. The horizon was cloudy, or perhaps it 

 might with more propriety be said that the surface of the 

 sea was covered with a dense fog of many yards in height, 

 and which gradually receded before the rays of the sun." 



An illusion of a different kind, though not less interest- 

 ing, is described by the Eeverend Mr. Hughes in his 

 Travels in Greece, as seen from the summit of Mount 

 ^Btna. " I must not forget to mention," says he, " one 

 extraordinary phenomenon which we observed, and for 

 which I have searched in vain for a satisfactory solution. 

 At the extremity of the vast shadow which Mtna, projects 

 across the island, appeared a perfect and distinct image of 

 the mountain itself elevated above the horizon, and 

 diminished as if viewed in a concave mirror. Where or 

 what the reflector could be which exhibited this image 

 I cannot conceive; we could not be mistaken in its 

 appearance, for all our party observed it, and we had been 

 prepared for it beforehand by our Catanian friends. It 

 remained visible about ten minutes, and disappeared as 

 the shadow decreased. Mr. Jones observed the same 

 phenomenon, as well as some other friends with whom I 

 conversed upon the subject in England." 



It is impossible to study the preceding phenomena 

 without being impressed with the conviction that nature 

 is full of the marvellous, and that the progress of science 

 and the diffusion of knowledge are alone capable of 

 dispelling the fears which her wonders must necessarily 

 excite even in enlightened minds. When a spectre 

 haunts the couch of the sick, or follows the susceptible 

 vision of the invalid, a consciousness of indisposition 

 divests the apparition of much of its terror, while its 

 invisibility to surrounding friends soon stamps it with 

 the impress of a false perception. The spectres of the 

 conjurer too, however skilfully they may be raised, quickly 

 lose their supernatural character, and even the most 



