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THE AMERICAN MUSEUM JOURNAL 



lateral, superior, or multiple mirage are 

 abnormally elongated vertically, or ap- 

 pear deformed, broken, and repeated, 

 such as described in observation (10), a 

 variety of mirage called "Fata IVIor- 

 gana" is said to exist [page 523]. The 

 light rays instead of being bent in plane 

 and regular strata of air, as in the other 

 types of mirage, are refracted in curved 

 and irregular strata. ]\Iagnification of 

 objects may occur in all directions, l)ut 



fairy Morgana, of Arthiu-ian romance. 

 The phenomenon generally occurs in 

 the morning in very calm weather. 



Fata Morgana is of frequent occur- 

 rence in the polar regions in the vicinity 

 of distant floating ice rafts. Slight irreg- 

 ularities on the ice floes appear as lofty 

 pinnacles. Open lanes between the ice 

 floes sometimes appear as dark vertical 

 lines. Scott, Mawson, and members of 

 the Scottish National Antarctic Expedi- 





The illusory appearance of a brilliant pool of water reflecting trees and other objects, is well known to travelers 

 in the desert. It is due to the layer of warm rarefied air above the surface of the hot sand, which refracts rays of 

 light from objects beyond it and makes inverted images of them appear to the observer. The sky near the horizon 

 is refracted in the same manner, producing the deceptive lake. From LMckyer 



chiefly vertical — parallel with the axes 

 of cylindrical air fields. If these fields 

 should be broken or repeated several 

 times and remain far distant from one 

 another, the images produced will have 

 a similar distribution. 



This form of mirage is often observed 

 on the seashore at Naples, Reggio, and 

 on the Sicilian coast. The Italians have 

 named it "Fata Morgana" after the 



tion have noted this form of mirage ap- 

 pearing on the ice field of the great 

 Antarctic continent where crevasses or 

 cracks appear in the ice. Warm air 

 rising from these cracks into cold air 

 varying in temperature from 22° F. 

 above zero to 20° below, raises points of 

 ice only a foot or two in height into 

 battlements with castellated towers. 

 When the sea is apparently concave 



