PECULIAR FOG IN ICELAND. 151 



mixed with larger particles than we generally see, caused 

 probably by the excess of ash driven up the chimney. 

 Gradually it came on to us; there was no smell, but a 

 distinct chill. " It is not smoke ; it is fog," We went up 

 the rising ground that leads to the tower on the great in- 

 land road, and we saw the fog rising out of the small lake 

 or pond behind the town and rolling into the streets very 

 slowly. As this advanced, a similar fog rose from the sea 

 and rolled also into the town, so that the two met in the 

 streets. It is clear, therefore, that wind had nothing to 

 do with the matter, but that both rolled from the fact 

 that they were too heavy to remain suspended. I will 

 not say that this is uncommon; but I will say that it 

 was accompanied here by a larger size of particle than I 

 have ever seen, and that the flatness with which it fell on 

 the ground and the lumbering mode of rolling distin- 

 guished it from all fogs which I have seen. It was not 

 even common there, because the people took it for dust; 

 and dust it certainly looked like, in part because the whole 

 body of the fog was not composed, I believe, of particles 

 equally large; had it been so, it would probably have 

 been more transparent. I have seen the fogs of great 

 cities at their worst, and have watched fogs and clouds on 

 the plains and hills, and been enveloped in both so often 

 as to make many of their phenomena familiar (I cannot 

 say all, because there seems to be no limit to their varia- 

 tions of appearance) ; but I have not at any time seen any 

 approach to the strange sight at Reikjavik. After stand- 

 ing on the hill and looking at the fog, with the chimneys 

 of the small town standing out of it, we came down ; but 

 the air had become clear. The fog lasted only about an 

 hour and a half. 



On examining the particles with the aid of a magnifier, 

 somewhat of the same power as that used by Saussure 

 when he made the observations to be spoken of, I con- 



