Atmospherical Phenomena of the Mock Suns.
[n.d., c.1820.]
Etching, sheet 120 x 165mm. Trimmed within plate.
Mock suns, sun dogs and false suns are common names for the bright spot of light that sometimes appears on either side of the Sun, the same distance above the horizon as the Sun, and separated from it by an angle of about 22°. They usually show a red edge on the side closest to the Sun. On some occasions the entire spectrum of colors can be spread out in the sun-dog spot but, commonly, the red edge is followed by an orange or yellow band that merges into a diffuse white region. The effects result from the refraction by sunlight through small, flat, hexagonal-shaped ice crystals falling through the air such that their flat faces are oriented nearly horizontally. Book illustration, numbered 'Page 184' lower right.
[Ref: 9537] £45.00
Etching, sheet 120 x 165mm. Trimmed within plate.
Mock suns, sun dogs and false suns are common names for the bright spot of light that sometimes appears on either side of the Sun, the same distance above the horizon as the Sun, and separated from it by an angle of about 22°. They usually show a red edge on the side closest to the Sun. On some occasions the entire spectrum of colors can be spread out in the sun-dog spot but, commonly, the red edge is followed by an orange or yellow band that merges into a diffuse white region. The effects result from the refraction by sunlight through small, flat, hexagonal-shaped ice crystals falling through the air such that their flat faces are oriented nearly horizontally. Book illustration, numbered 'Page 184' lower right.
[Ref: 9537] £45.00