884 Transactions,— Miscellaneous. 
of the sun-glows in different places are so important; e.g., we could tell the 
rate of progress of the dust to us in Nelson pretty well if we knew for 
certain when the glows first appeared in Port Darwin, Brisbane, Sydney, 
and Nelson. Unluckily people did not attach much scientific importance to 
the phenomena when they first appeared, and so made no notes. 
5. The intermittent nature of the phenomena, also, Hazen thinks, is 
against the supposition that dust is the cause; but I see no force in this. 
It is only natural that the appearances should vary in intensity with vary- 
ing meteorological and atmospherical conditions, and, as I have already 
said, the dust may not have been very evenly distributed. 
6. Hazen’s last objection is that ashes are opaque, and the appearances 
indicate a transparent something. Another writer (in the “ Sei. Amer.”) 
puts this objection in this way :—He says, earthly or lunar volcanic dust 
cannot be the cause of the glows at the rising and the setting of the sun, or 
the ordinary light from sun, moon, Mars, Jupiter, etc., would be affected. 
But there is no diminution of this light. Therefore the cause of the glows 
lies far beyond the sun’s orbit. 
But are the premises in this argument true? Have we not already 
stated that a haziness of the sun has been observed at several places—e.g., 
at Seychelles and Tokio? And is not a change in the colour of the sun 
and moon virtually a change in the intensity of their light? Moreover, 
although individually the particles may be opaque (which their intense 
character leaves open to doubt), collectively they do not constitute an opaque 
mass, being exceedingly minute and widely scattered. Also, before we can 
attach much importance to this objection we must know accurately what 
the photometer has to say on the subject. As the writers quoted do not 
tell us this, we may presume they speak from conjecture only. 
7. Some may say that the volcanic force of Krakatoa, however great it 
might be, would scarcely be great enough to force up such a vast amount of 
ashes to so great a height, It is generally considered that the dust cloud, or - 
whatever it was, lay very high indeed; but what gigantic forces were at 
work at Krakatoa! An electrical force was in violent action also, for 
simultaneously with the outbreak all the telephones in Singapore were 
unworkable, and on one line reports like pistol shots and a mighty roar 
were continually heard; and again the heated air, emanating from the 
crater of Krakatoa, would carry with it to unknown heights vast volumes of 
dust, ete. ; and incidentally I may mention that the heated air of the tropics 
ascending as it always does, to be replaced by cooler air from the north and 
south temperate and polar zones, would aceount to some extent for the dis- 
persal of the dust, 
