ATMOSPHERIC REFRACTIONS. 
165 
tinetly defined, and especially the latter, which 
appeared as usual, in an inverted position in the 
air. (Plate V. Fig. 1.) Of some vessels, whose 
hulls were beyond the horizon, there were two, 
and of one ship three, distinct inverted images, 
each exhibited in a different stratum of refracted 
ice, one above another,—the lowest image being at 
an altitude of more than the apparent height of 
the ship’s mast, above the mast-head of the origi¬ 
nal. And of two vessels there were well defined 
images, in an inverted position, though the ships 
to which they referred were not within sight! It 
should be observed, that the inverted images were 
visible on this occasion, only, when an appearance 
of ice, produced either by reflection or refraction, 
occurred above the regular line of the horizon, in 
the quarter occupied by the ships: in the clear in¬ 
tervals of the lower atmosphere between the strata 
of refracted ice no image was seen; and when the 
stratum was too narrow to comprise the whole 
of the image, a part of it only appeared. And it 
should be also observed, that these phenomena 
were principally telescopic, both the ships and 
images being so distant, that, to the naked eye, 
they only appeared as indistinct specks. The in¬ 
verted images occurred either in the south-west, 
or north-east quarter; but at the same time, the 
ships in the north-west quarter were only sub- 
