126 REPORT—1883. 
curves for atmospheric pressure, temperature, and humidity have been 
calculated for Fort William. These curves are interesting and valuable 
as showing the eminently insular character of the climate of the region 
round the base of Ben Nevis from which the air is drawn which ascends 
its slopes on a summer’s day. The curves of pressure, temperature, and 
humidity for the top of Ben Nevis from 9 to 11 a.m. are also highly 
interesting and important, especially when compared with the curves for 
these hours at Fort William. The degree of saturation’ of the atmo- 
sphere and its persistency on the top of Ben Nevis during these hours of 
the day is perhaps the most important meteorological feature of the 
climate of this elevated region: and this feature is all the more pro- 
nounced when a cyclone is advancing from the Atlantic. 
This type of weather prevailed, with few and short-continued inter- 
ruptions during the whole season of 1881. But in 1882, isolated periods 
of fine weather and well-marked anticyclones occurred in Scotland, when 
the atmosphere at the top of Ben Nevis passed from a state of saturation to 
a state of extreme dryness—a dryness indeed greater than could be found 
anywhere nearer than the region of the Sahara. These violent contrasts 
are often separated from each other by exceedingly short intervals of time 
and of space. It is to be noted that the extremest cases of dryness have 
only been observed at the very top of the mountain and were in every 
case accompanied by a very high temperature for that height. This 
peculiarity marks the Ben Nevis Observatory as admirably suited for the 
prosecution of some hygrometric and other physical inquiries which are 
so urgently called for in the present state of meteorology. 
It is expected that the discussion of these observations will be com- 
pleted by Mr. Buchan, and the results published, in the ‘ Journal of the 
Scottish Meteorological Society,’ early next year. A copy of the ‘ Jour- 
nal’ will be sent to the British Association. 
Report of the Committee, consisting of Professor ScHuUSTER (Secre- 
tary), Sir Witt1am THomson, Professor H. E. Roscor, Professor 
A. S. HERSCHEL, Captain W. DE W. Apney, Mr. R. H. Scort, 
Dr. J. H. GuapsTonE, and Mr. J. B. N. HEeNNESSEY, appointed 
for the purpose of investigating the practicability of collecting 
and identifying Meteoric Dust, and of considering the question 
of undertaking regular observations in various localities. 
Tue work of the Committee during the past time consisted chiefly in the 
examination of some solid residues of Himalayan ice. The ice was boiled 
down according to instructions of one of the members of the Committee 
(Mr. J. B. N. Hennessey) by a surveying party, who forwarded to the 
Secretary three specimens. One of these came from the Gamukdori 
Pass, on the watershed between the Indus and the Kishenganga (lat. 35° 5’, 
long. 74° 13’), at an altitude of 13,400 feet; and two from the Shokari 
Pass (lat. 35° 0’, long. 74° 38’, altitude 14,700 feet). There is no human 
habitation near either of these places. The amount of snow boiled down 
was about 25 cubic feet, and the solid residue was about the same in all 
three cases, weighing a little over ‘1 gramme. It consisted chiefly of 
organic matter, due principally to birds, but a quantity of magnetic 
particles was also found in them. The magnetic matter in great part is 
due to ferruginous rocks, and must have been brought by the wind to the 
