MIRAGES—GORDON Sor 
or mountains in a group, etc. There may be also a lifting of the 
whole distorted object or scene. Oddly enough, these operations are 
carried out mostly over water surfaces not far from shore and over 
near-desert areas. Examples are the famed Fata Morgana over the 
Straits of Messina, similar effects off the northern Japanese Islands, 
off our New England coast, over the Great Lakes, off the California 
coast near Santa Barbara, and so on. The desert country, too, spe- 
cializes in them; that is where I have seen them. They may be very 
near. A man crossing a field may develop stiltlike legs, freight cars 
on a siding may seem to stretch up to more than double height, a row 
of trees may stretch far up. Then there are a wide variety of forms 
of great complexity. 
Mirages are definitely not photogenic. To the eye and through 
binoculars they often look substantial enough, but I have repeatedly 
seen the mirage image of a distant mountain through the image of a 
nearer one, which lack of substance perhaps the camera recognizes. 
Distance to the mirage is often great enough to be a photographic 
problem. Probably the best explanation of the almost complete 
absence of mirage pictures is the infuriating fact that on the rare 
occasions when a good picture might be had, one never has his camera 
and there is not time to get it. 
Lacking photographs, I have drawn a number of silhouettes to 
show some of the mirage forms and processes occurring in the desert. 
Between object and observer and evidently essential for the formation 
of the temperature-inversion layer which must supply the huge air 
lens needed, there must be a large area of approximately flat land, 
frequently many square miles in size. This may be drawn in, in your 
imagination. 
In the mirage known as Flattop (fig. 2), elevation of the highest 
hill in the group, for reasons not known, always seems to establish 
the height of the whole structure. The lesser ones build up to that 
height. The building process may stop at any point and reverse 
itself, sometimes for a fresh start, sometimes to end the show for the 
day. It is an amazingly deliberate and systematic operation, pro- 
ceeding to follow the pattern exactly, time after time, year after year, 
in this place and others. Apparently depending on the lay of the 
land between object and observer, there are probably half a dozen 
or more variations on this general procedure, but none of those varia- 
tions forms a flattop. 
Such a full development as the drawings show may come about in 
perhaps 15 to 30 minutes. The completed picture never appears 
suddenly. The image must be built up according to rule and removed 
the same way. 
Watch, if you will, how it grows. From the lower hills, perhaps 
no more than a knob on the horizon, a feeler reaches up to the height 
