INVERTED IMAGE OF A SHIP. 207. 



this he gave a telescope to a person present, who, upon 

 attentive examination, saw also a very clear image of the 

 castle, as the Doctor had described it. He continued to 

 observe it for about twenty minutes, during which time 

 the appearance remained precisely the same, but rain 

 coming on, they were prevented from making any further 

 observations. Between the observers and the land from 

 which the hill rises, there was about six miles of sea, and 

 from thence to the top of the hill there was about the 

 same distance. Their own height above the surface of 

 the water was about seventy feet. 



This illusion derived great force from the remarkable 

 circumstance, that the hill itself did not appear through 

 the image, as it might have been expected to do. The 

 image of the castle was very strong and well denned, and 

 though the rays from the hill behind it must undoubtedly 

 have come to the eye, yet the strength of the image of the 

 castle so far obscured the background, that it made no 

 sensible impression on the observers. Their attention 

 was, of course, principally directed to the image of the 

 castle; but if the hill behind had been at all visible, 

 Dr. Vince conceives that it could not have escaped their 

 observation, as they continued to look at it for a consider- 

 able time with a good telescope. 



Hitherto our aerial visions have been seen only in their 

 erect and natural positions, either projected against the 

 ground or elevated in the air ; but cases have occurred in 

 which both erect and inverted images of objects have 

 been seen in the air, sometimes singly, sometimes com- 

 bined, sometimes when the real object was invisible, and 

 sometimes when a part of it had begun to show itself to 

 the spectator. 



In the year 1793, Mr. Huddart, when residing at 

 Allonby, in Cumberland, perceived the inverted image of 

 a ship beneath the image, as shown in Fig. 32 ; but 



