of Edinburgh, Session 1885-86. 
843 
draught of the land and sea breezes ; that the southerly winds of 
noon were the overflow from a low-lying cyclone occupying central 
Scotland, and that the midnight westerly winds were the return 
current from the lower night land wind feeding an anticyclone 
similarly placed ; while the northerly winds shortly after sunrise 
could only be accounted for by supposing the daily cyclone to 
originate in the upper atmosphere shortly after sunrise, and extend 
downwards as the heat of the day increased, finally dying out at a 
low level. 
2. The Meteorology of Ben Nevis. By Alex. Buchan, M.A. 
From the commencement of the meteorological researches on Ben 
Nevis, a double set of observations have been carried on — one set on 
the top of the Ben, and the other at a station at Fort William near 
the level of the sea. It is not so much from the observations made 
on the top considered by themselves, as to their relations to those 
made at the base, that we may hope to arrive at a better knowledge 
of the atmosphere, and particularly at a better understanding of the 
principles of weather forecasting. Accordingly, both stations were 
from the first fitted up with the best instruments. 
The observations on the top are made hourly, and those at Fort 
William six times a day ; and to the latter station, in addition, a 
barograph and a thermograph have been added, the results of which 
are particularly valuable as affording a ready means of detecting 
inadvertent errors of observation or of transcription. Thus the 
system of observation for Ben Nevis yields as trustworthy records 
as can possibly be obtained. As regards the observations of tem- 
perature at the Observatory, it is absolutely necessary that these 
be made with the eye, owing chiefly to the heavy snow-drifts and 
incrustations of ice, with which everything exposed to the free 
atmosphere gets frequently covered. Owing to the violence of the 
winds which occasionally blow for hours together at a mean velocity 
of about 120 miles an hour, maximum and minimum thermometers 
do not give trustworthy results. 
Mr Omond and his staff of assistants went into residence in the 
end of November 1883. The present paper deals with the two and 
a half years’ observations from that date, to May 31, 1886. From 
