344 J. E. Willet on Indian Summer. 
oe by violent N. E. winds. In these countries (Germany and 
olland) the dry fog is coincident with the burning of peat; 
when the airis dry, tl | i pended in the atmosphere 
and may be carried away by the winds. The wind always blows 
from the direction of the peat bogs, when dry fog is manifested; 
and fogs have frequently been seen coming distinctly from the 
peat bogs.” “The very thick dry fog of 1834 came partly from 
the combustion of peat, and partly from the fires for which this 
year was noted.” ‘To the same cause, probably, may be attrib- 
uted the particular aspect of the airin autumn. In the fine days, 
when the air is very dry, the air is less transparent; distant ob- 
jects are not seen distinctly, they appear surrounded by a slight 
fog.” “Can the dry fog of 1783, which was diffused over a 
great portion of Europe, be attributed to the same cause?” Pop- 
ular superstition in Europe attributes to this “dry fog” “ the 
disease of smut in corn, and diseases in vegetables generally, 
and “the predominance of the north winds which then prevail, 
and they say that it drives away rain and storms, and is a cause 
of cold.” : 
The above description of “ dry fog” accords very well with 
the appearance of many occasional smoky days in this country, 
which, if they occurred in autumn, would be styled Indian sum 
mer. Relying upon the description alone, I am inclined to class 
them together. Kaemtz, also, in the description above, of “ the 
pprticolag aspect of the air in autumn,” seems to allude to the 
rerman Indian Summer, and thus connects together the phe- 
nomena of dry fog and Indian Summer. : 
So much for the facts, let us now turn to the theory of Indian 
Summer. a 
Any theory, to be complete, must equally apply to these 0 
casional Soaks days, lean are distributed sconaheadh the po 
for these present exactly the same characteristics, and are note¢ 
by observers, as Lieut. Whipple and Lieut, Gilliss, in prosiegy 
the same terms, as the groups of autumnal days, com 
ed Indian Summer, 
rat smokiness is produced by real smoke, proceeding from 
eo : x 
