368 Transactions . — Miscella neous. 



the aqueous vapour theory should be advanced to account for the sun-glows ; 

 as it was brought forward under somewhat similar circumstances, herein- 

 after referred to, in the year 1783, by the philosopher Lalande, so it first 

 occurred to many eminent astronomers and meteorologists (Mr. Ellery 

 amongst the number) of the present day ; and although in most cases 

 the theory was subsequently abandoned, yet at first it was maintained 

 vehemently, and most other theories treated with contempt. With Mr. 

 Ellery of Melbourne the aqueous was one of his two admissible theories, and 

 that which he strongly advocated. He said — there is unusual moisture in 

 the upper air — our exceptionally wet season proves it. The average rain- 

 fall for January is 1-60 inches. This year it has been 4-75 inches. Such 

 exceptional moisture in the air will account for the sun -glows (Eoyal 

 Society, Melbourne, 15th November). But, unfortunately for this theory, 

 as it happened, the season in New South Wales, the neighbouring colony, 

 was exceptionally dry, as the squatters there know to their cost. The 

 drought was so severe indeed that it brought about a loss to the colony in 

 one way or another of £10,000,000, and again in North China (from the 

 testimony of a Mr. Sowerby in " Nature") the winter was remarkably fine. 

 Yet in both New South Wales and China the sun-glows were brilliant — 

 those in China, in the month of December, being described as gorgeous 

 with magnificent rose-pink after-glows. Mr. Ellery, furthermore, says that 

 an assistant of his at Port Darwin, in March, 1883, saw several such sunsets 

 as we have had with similar after-glows, and that they always came before 

 or after rain. Herein the Government Astronomer of Victoria strangely 

 loses sight of the fact that before or after rain, as it appears to me, makes 

 all the difference hi the world, for if the sun-glows continue to appear after 

 a rainy season, and during a succeeding dry one, as they have done in Vic- 

 toria, it is clear that they must be produced independently of aqueous 

 vapour in the air. As far as our experience here in Nelson is concerned, I 

 do not think there can be any doubt whatever that our finest sun-glows 

 occurred during a spell of dry, keen, and exceptionally cold weather. More- 

 over, the air of England is wet enough in all conscience, yet fine sunsets 

 are comparatively rare there, and green suns almost an unheard-of pheno- 

 menon. Dr. Hector,* again, as I have already quoted, spoke on the 14th 

 November, 1883, of the extraordinary coloured glow in the sky, as proving 

 the existence at an enormous altitude of vapourous matter capable of 

 refracting the sun's light into its prismatic components. Except that 

 the expression employed here is " vapourous matter " — in the place of 

 " aqueous vapour " — the language is not at all doubtful. The context, 

 however, states that the vapour must have an unusual altitude, that 



* Trans. N.Z. Inst., vol. xvi., p. 556. 



