ON ATMOSPHERIC WAVES. 149 
The crest No. 2 passed Cork, Belfast and the Orkneys on the 5th, Ply- 
mouth on the 7th, and Paris on the 8th, with a diminution of oscillation. 
We find however no diminution of oscillation at Christiania as compared with 
Plymouth. It is highly probable, the subsidence of the crest, as it proceeded 
towards Paris, resulted from the influence of the land in England, while both 
at Plymouth and Christiania the crest was but slightly interfered with by 
the influence of land, the difference of level resulting from the anterior slope 
of crest No. 3. 
These considerations exhibit a large wave of considerable breadth and slow 
motion, extending in a longitudinal direction from the extreme south-west of 
England towards the Swedish capital. 
Nov. 10.—Mr. Brown’s diagram for this day very distinctly and beautifully 
exhibits the change of currents resulting from the transit of crest No. 3, as 
well as from the progress of the posterior trough of crest No.2. The trough 
of the latter wave is now between the Orkneys and Paris (the deep trough 
before mentioned), the wind in the south-eastern portion of the diagram is 
S.W., the strength increasing-towards the trough. At Thurso and North 
Shields the wind is N.W., the anterior slope of crest No. 3; in the south- 
west of Ireland, the wind is S.E. (posterior slope). The N.E. wind on the 
anterior slope of the wave succeeding crest No. 2 is seen on the north-west 
side of the trough. 
November 11, 1842. 
Crest No. 2. 
s.W.——_____—_————_N.E. 
Crest No. 3. 
N.W.—__—_—————-S.E. 
Max. Christiania ...... 29°48 Crest No. 3. 
3 sea 7 het, site \ Under posterior slope of Crest No.2. 
ee ‘dibt pins In the neighbourhood of posterior 
Shields... .l..u0. gaooe} ) troughs Crest No.2, 
Cork .......... 28°91} Posterior trough, Crest No. 3. 
( Under anterior slope of wave succeed- 
Meliast tes 29°02 . : 
2 ing Crest No.2 and posterior slope 
Orkneys ........ 29°24. i i aa No. 3. P P 
Max. Christiania ...... 29°48 
Orkneys ‘o/s 29°24: 
 Belfast.......... 29°02 >Under posterior slope, No.3. 
Shields........ -. 28:99 | 
Cork stent auatt.« 28°91 J 
London ........ 29°00 
Paris: ii6 oes wie) ast 202) 
ie aa ahr page Under posterior slope, No. 2. 
emis ih oda 28°91 
Slopes.—Lines of greatest diminution of pressure. 
On posterior slope of Crest No.3. Christiania to Cork.. *57 « 
On posterior slope of Crest No 2. Paris to Cork ..... » “34 
Currents —Wind on N.W. side of Crest No.2, S.W. 
i S.W. 7 ef 3, S.E. 
* Depressed by posterior trough of Crest No. 2. 
+ Depressed by posterior trough of Crest No. 3. 
