84 Singular Irridescent Phenomenon. 



(J. C. Mounsey, Sunderland) from whose written description 

 I have gathered the following particulars : — 



" The morning was very misty, and the barometer high 

 (30*35 Whitehaven) ; between 10 and 11 A.M., the mist 

 cleared off, the sky became cloudless, and the air calm, the 

 Lake being of a glassy smoothness. At ll h we went on the 

 lake, and, in about half an hour I observed brilliant prismatic 

 colours on the water near the shore, say half a mile or more 

 distant, but no appearance of a bow. I rowed towards the 

 spot, and, in doing so, the colours increased in extent and 

 brilliancy. 



" There were two bows, which resembled ordinary rain- 

 bows inverted ; both were exceedingly brilliant at the extre- 

 mities, and became gradually fainter as they receded from 

 the shore. 



" The outer bow came completely down to the boat, which 

 appeared to prevent our seeing the crown of the arch ; its 

 extremities also proceeded from the shore, and its centre was 

 apparently under the feet of the spectator. In both bows, 

 the red was on the outside and the violet on the inside, and, 

 in both, the light and colours were most brilliant and distinct 

 at the extremities, or points of conveyance at the water's 

 edge. I am certain there was no rainbow in the sky at the 

 time, neither was there any solar halo or any other pheno- 

 menon in the air that I observed, of which this could be the 

 reflection. I observed that, wherever the prismatic pheno- 

 menon shewed itself, there was a sort of scum on the water, 

 as though there was some fine dust or bubbles on the surface. 

 I put my finger into the water, and found it so dirty as to 

 leave a distinct mark behind, which leads me to think that 

 what I at first took to be small bubbles must have been some 

 sort of dust. Whatever it was, it appeared to me to be the 

 cause of the irridescence, as, wherever it was lost, the bows 

 disappeared. 



" The bows were visible about an hour, and, in looking at 

 them, the sun was, of course, directly behind the spectator. 



" The boatmen say, they have sometimes (though very 

 rarely) seen a similar phenomenon after the disappearance 

 of a mist from the surface of the water." At Whitehaven, 



