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These results are not expected by the simple theory of refraction ; 

 they demonstrate the action of diffraction. It is these very properties 

 which, for the rainbow, made tiie ordinary refraclion-theory insufticient. 



Evidently the conditions for the development óf these phenomena 

 of diffraction are present rather frequently. With great certainty this 

 research has established the conclusions di-awn in the first paper. 

 The observations however difficult by the small power of the colours, 

 which generally are to be taken as mixed colours, the records, 

 however often delusive by personal influences sufficiently show, that 

 in the formation of halos the diffraction plays an important part. 



