of Edinburgh, Session 1868 - 69 . 
413 
us and our visitors. I have often made the same prognostication 
since, and with invariable accuracy ; and several friends to whom 
I have mentioned it have made the same observation — viz., that 
the first great aurora occurring after a long tract of fine autumnal 
weather, foretells a storm commencing between twelve and two 
o’clock in the afternoon of the second day thereafter. I restrict 
the prognostication to these conditions. It is evident how valuable 
the knowledge of it may often be to agriculturists. Nevertheless, 
I never met with farmer or farm-servant who knew it. On one 
occasion it was the means of saving the corn crop of a friend in 
Dumfriesshire, whose farm-steward was about to leave his corn 
half led on the day after a very great aurora, and, deceived by the 
beauty of the weather, was on the point of taking his labourers to 
other work not at all pressing. His master, trusting to my positive 
assurances, ordered him to make haste in leading and thatching 
everything, and great was the steward’s astonishment when a 
furious three days’ storm set in on the forenoon of the second day. 
In the pneumatic branch of meteorology three papers were pro- 
duced to the Society, in the latter part of last century, on topics of 
great interest to us. 
Mr George Wallace, a member of the bar, read, in 1787, “A 
Dissertation on the Causes of the Disagreeableness and Coldness of 
the East Wind ; ” but as the notice in the Society’s Proceedings 
merely informs us that “ the author did not incline that any 
abstract should be given of his dissertation,” and I cannot find that 
it was published elsewhere, we are left in ignorance what were 
the discoveries or opinions of Mr Wallace on this knotty question, 
in which we must all take a lively personal interest. It may be 
that this gentleman has withheld from the world one of the most 
valuable practical discoveries which remain to be made in meteor- 
ology. It may be, however, that he was deterred from having any 
notice taken of his lucubrations by learning certain views enter- 
tained of the same subject by Hutton ; who communicated them to 
the Society in an able paper “ On our Vernal and Autumnal 
Monsoon Winds,” in February 1791. 
In this paper he points out that winds are shiftings of the air, 
occasioned by changes in its temperature ; that these changes arise 
from the alternations of day and night, the alternate crossing of the 
