154 LETTERS ON NATURAL MAGIC. 



The spectre of the Brocken and other pheno- 

 mena of the same kind, have essentially a 

 different origin from those which arise from 

 unequal refraction. They are merely shadows of 

 the observer projected on dense vapour or thin 

 fleecy clouds, which have the power of reflecting 

 much light. They are seen most frequently at 

 sunrise, because it is at that time that the vapours 

 and clouds necessary for their production are most 

 likely to be generated ; and they can be seen only 

 when the sun is throwing his rays horizontally, 

 because the shadow of the observer would other- 

 wise be thrown either up in the air, or down upon 

 the ground. If there are two persons looking at 

 the phenomenon, as when M. Haue and the 

 landlord saw it together, each observer will see 

 his own image most distinctly, and the head will 

 be more distinct than the rest of the figure, 

 because the rays of the sun will be more copiously 

 reflected at a perpendicular incidence : and as, 

 from this cause, the light reflected from the 

 vapour or cloud becomes fainter farther from the 

 shadow, the appearance of a halo round the head 

 of the observer is frequently visible. M. Haue 

 mentions the extraordinary circumstance of the 

 two spectres of him and the landlord being 

 joined by a third figure, but he unfortunately 

 does not inform us which of the two figures was 

 doubled, for it is impossible that a person could 

 have joined their party unobserved. It is very 

 probable that the new spectre forms a natural 

 addition to the group, as we have represented it 

 in Fig. 30 ; and, if this was the case, it could 

 only have been produced by a duplication of one 

 of the figures produced by unequal refraction. 



