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Proceedings of the British Association. 311 
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to be used in the construction of the new catalogue of the Astro- 
nomical Society.. No money has been spent during the year; but 
of course, a renewal of the grant will be desirable-—Signed for 
the committee, J. F. W. HerscHe. 
j ort on the reduction o 3 Meteorological Observations made 
at the equinoxes and solstices, on the 2 part of a committee appointed 
in 1838.—Sir J. Hor@twigaaterting to his report of last year for 
the reasons why the reduction of these observations was not im- 
mediately commenced, reports further that the same reasons de- 
layed any effective commencement of the work until very lately ; 
but that owing to several wanting series of observations having 
at length come to hand, so as to render the series for the years 
1835-8 tolerably consecutive, at least for several localities, your 
Committee considered it advisable to wait no longer, but proceed 
to work with the materials in hand. Accordingly, having cast 
the plan of. operations for the comparison and projection of the 
barometric oscillations in those years, (to which for the present, 
your Committee propose to limit their proceedings, till it shall ap- 
pear whether a further and more complete comparison, ineluding 
the thermometric changes, and especially the correspondence of 
the winds, seems likely to lead to any valuable conclusions,) the 
reduction, arrangement and projection of the several series of 
observations was confided to the able and zealous hands of W. R. 
Birt, Esq., who now actively employed in this operation, and 
who has enabled your Committee to lay before the meeting, as 
specimens of the mode of proceeding, the tabulation and projec- 
tion of the observations made in the British Isles in the year 
1836, which are, accordingly, submitted for inspection. In the 
discussion of these observations, it has been found advantageous 
todivide the stations from which they have emanated, into groups, 
according to geographical proximity, the chief of which are,— 
the group of the British Isles, that of the continent of Europe, the 
North American, South African and Indian groups. Each of 
these groups is polanred by applying the differences of longitude 
to the times of observation, to a central station; and the projected 
Curves, in which the abscisse are the mean times at that station, 
and the ordinates the reduced barometric altitudes, exhibit at one 
View the correspondence or disagreement of the barometric move- 
ts for all the stations of the group. * * * The projection of 
curves is the first step in the process of reduction contem- 
