Mr. W. Brown on the Oscillations of the Barometer. 279 



although in the south during the blowing of a south wind ($ 6). 

 On the remaining clays of this series the north wind continues 

 on the whole to gain in predominance over the south, and to 

 cause the barometer to rise, not however without a check in the 

 south, where the south wind again increases in strength for a 

 time, and causes a slight depression of the barometer on the 

 14-th and 1 5th, which has its limit northward in the north of 

 England or south of Scotland, where the force of the wind is 

 balanced by the opposite current, repeating the phaenomena 

 of the 13th, though with this difference, that on the 15th the 

 north wind prevails to a greater degree than on the 13th, so 

 that at North Shields the north-east wind itself is blowing; 

 still however there is a slight fall of the barometer (§ 5). On 

 the 16th the south wind has greatly decreased, and serves only 

 to produce the great comparative rise of the barometer at Ork- 

 ney (§ 7), where it attains a height considerably above the 

 mean. On the 17th, the day on which the barometer attains 

 its maximum elevation, we have very little indication of the 

 south wind blowing on the south; it is however blowing on 

 the west, and accordingly we find the elevation beginning in 

 the north-west and extending itself towards the south-east ; 

 now as this is the direction in which the point of C of fig. 1, 

 whether the point of depression or elevation moves, and this 

 elevation differs from that of the 4th, during which also the 

 opposition of the south wind was on the west, in extending 

 eastward and south ; and also as in many previous instances 

 the south wind merely retreated, and did not altogether dis- 

 appear when the north wind advanced; we may infer that in 

 the present case it is yet blowing in localities southward of 

 the latitudes included in the diagram. If not, the phaeno- 

 mena yet admit of easy explanation, on the supposition that 

 the north-east wind, which is blowing with great strength, 

 occupies (j 9) a greater proportion of the height of the at- 

 mosphere than the equal flow of the upper current admits of. 



Names of Places. 



Orkneys ... 

 Glasgow ... 

 Belfast ... 

 Armagh ... 

 Shields ... 



Cork 



Bristol ... 

 Plymouth 

 London . . . 



Paris 



Christiania 



IS. 



-•16 

 -•05 



-03 

 -•07 

 -05 

 -02 



+•03 

 +•04 

 +•22 

 +•19 

 -13 



-11 



-•04 

 -•11 



+•05 

 -14 



-•36 

 -12 



-14 



-•08 



+•03 

 +•06 



19. 



-•44 , — -07 



-•30: --17 



+-o;j 



-•02 



-•04 

 -•15 



-•31 

 -•27 



-•26 

 -•18 



20. 



+•04 

 + 12 

 +•08 



•00 

 + •12 

 -•16 



•00 

 -•18 

 -•27 

 -•44 

 -■18 



-•03 



■00 

 +•04 



-•02 



-02 

 +•02 



•00 

 +•01 



-•20 



-•70 

 -•08 



