ON ATMOSPHERIC WAVES. 
353 
near Arbroath, east of Scotland, at 3 p.m. of November 12th, the crest of the 
first subordinate wave on the posterior slope, value SO’66. This wave at this 
station, and indeed at all the northern stations, was so strongly developed as 
to appear in the form of a large protuberance on the back of the symmetrical 
wave. The culmination of die great wave occurred at 6 p.m. of the 10th, 
value 30*64; the fall immediately after this cuhnhiation was slight compared 
with that at Ramsgate, value *00; the barometer commenced rising at St. 
^'igcaa’8 earlier than at Ramsgate. 
At Stornoway in the Western Isles, tlie curve obtained from observations 
made on board H.M. ketch .Sparrow, under the direction of Commander 
Otter, presents a most striking and marked difierence to that representing 
the observations at Ramsgate. .At the commeucenient of the great wave the 
barometer at the Western Isles was more than half an inch below that at 
Ramsgate, wind S.W., force 9. The two anterior waves, which were scarcely 
perceptible at Ramsgate, we.re well-developed nl the Western Isles, the baro¬ 
meter at the latter station gaining on that at Ramsgate during their transits. 
On the evening of the 6tli both baroinetera began to rise, the one at the 
Western Isles very rapidly, so that at noon of tlio 8lh the pressure was equal 
at the two stations. The curves then diverged, Rainsgat*! being still supe¬ 
rior, and the movements being of an opposite character until midnight of the 
9th. The fall characterizing th« Ramsgate curve did not occur at the West¬ 
ern Isles; the curve at the latter station conUnued to nse until the forenoon 
of tlie 12th, wlien the altitude of the barometer was equal to that at St. 
Vigean's; these curves, Stornoway and St. Vigeaii s, run nearly together until 
the morning of the 15th, both being superior to Ramsgate ; at 9 p.m. of the 
15th the Stornoway curve crossea the Ramsgate, the barometer at the 
former station falling rapidly. At Stornoway the first wave oo the posterior 
slope of the symmetrical wave is so strongly developed as completely to 
mask the central wave. 
The following Tabic exhibits the plimnomena above noticed ; also the alter¬ 
nations of the barometric differences. 
Table 11. 
Barometric altitudes and diftereuces observed at Stornoway in the Western 
Isles north-west of Scotland, and Kamsgate south-east of Rngland, during 
the transit of the Great Symmetrical Wave of November 1846. 
Epoch, Nov. 
ItHIIlH. 
gule. 
If 
* S 
Epoch, Nov. 
Rntna* 
gate. 
Storno¬ 
way. 
Storno¬ 
way ±. 
2. 9 r.M . 
3. 3 A.M . 
9 A.M . 
3 P.M . 
9 P.M . 
4. 3 A.M . 
9 A.M . 
3 P.M . 
9 P.M . 
5. 3 A.M . 
3 P.M. 
9 P.M . 
6. 3 A.M . 
9 P.M . 
7. 3 A.M . 
9 A.U . 
3U-U8 
•25 
■29 
‘25 
•24 
•25 
■29 
•25 
•24 
•2« 
•30 
•21 
•20 
27 
•29 
•30 
•78 
•85 
•88 
•88 
•7« 
•80 
•8.5 
•90 
29- 96 
30- 06 
29-98 
•99 
29'98 
.3004 
•11 
- .55 
-•47 
—44 
-•37 
-•41 
-•49 
-•49 
-•40 
-•34 
—32 
-•24 
-•26 
-•21 
-•29 
-•25 
-•19 
7. 3 P.M . 
9 P.M . 
8. 3 A.U . 
9 A.M . 
3 P.M . 
9 P.M . 
9. 8 A.M....... 
9 A.K. 
3 P.M. 
9 P.M . 
10. 3 A.M . 
aA.M. . 
3 P.M . 
9 P.« . 
11.3 A.K . 
3 P.M. ...... 
30-37 
•37 
•38 
•40 
•46 
•49 
•50 
•54 
•53 
•53 
•49 
•56 
•50 
•40 
•30 
•29 
30-28* 
•30 
•35 
•40 
•43 
•45 
•45 
•45 
•48 
•50 
•53 
•53 
*53 
•57 
•55 
•58 
-•09 
-•07 
-•03 
-•03 
-•04 
-•05 
-•09 
-05 
-•03 
+ 04 
-•03 
+ 03 
+ 17 
+•25 
+•29 
2 A 
1847. 
* Reading at 4 p.«. 
