1854.] observed at Darjiling in the ffimalayak Mountains. 53 



Depending from the shoulders of the spectator is a dark neutral 

 tinted pyramidal shade, resembling a flowing garment, occupying 

 about 72° of the central disc. 



From the outside rim of the inner yellow circle, long pencil-like 

 rays of neutral tinted or gray colour, radiate in all directions, spread- 

 ing and increasing in size in proportion to their distance from the 

 centre, until lost in the surrounding haze. 



The fog-bows with these spreading rays are very beautiful objects, 

 but these rays are frequently wanting. 



Another fog-bow commonly seen at Darjeeling, consists of the 

 usual neutral coloured disc, one series of concentric circles exhibiting 

 violet, yellow, orange and blue (this latter colour it will be observed 

 is contrary to the regular order of the prismatic colours) beyond these 

 circles at three and half diameters of the disc, comprising the whole 

 of the four colours is the usual unicolour bow but no radiating pen- 

 cils of gray colour. Depending from the shoulders of the spectator 

 is the constant garment-like appendage. The figure reflected upon 

 the fog, follows all the motions of the spectator, who, is the accom- 

 panying sketch is represented with his hat in his right hand, whilst 

 the left hand is raised above his head. 



For the sake of easy reference I append the colours of the solar 

 spectrum, together with their values as ascertained by Sir Isaac 

 Newton ; also the order of the colours of the ordinary rainbow. 



Order of the colours as shewn when refracted by the prism : 



1. Violet, 80 



2. Indigo, 48 



3. Blue, 60 



4. Green, 60 



In the rainbow, 

 violet is nearest to 

 the sun. 



5. Yellow, 40 



6. Orange, ...... 27 



7. Bed, 45 



Total length, 360 

 and red furthermost from the sun. 

 The upper rainbow from being produced by two reflections and 

 two refractions of light, has its colours reversed. 



Another, but transient and hurried, phenomenon of the second 

 class is sometimes observed by a spectator, when he is standing with 

 his back to the sun and looking down from a height upon a bank of 

 snow-white cumuli, upon which the rising or very early sun is shin- 

 ing. 



