ON ATMOSPHERIC WAVES. 
357 
Distribution of Pressure. —In the following remarks the term wave is 
used in ike same sense as indicated in mg last Report, See definition 
and phmomena of an atinospheric wave. 
Distribution of Pressure. —In examining the distribution of pressure over 
the area of the British Isles, as inauifested by these observations, the first 
point that strikes our attention is the existence of a crest which extended 
from Jersey to Limerick on the* oveuiug of lhe4lh, and transited the stations 
in the following order: Jersey, I Iclstanc, Liirwrick. This crest was situated 
on the posterior slope of a wave, probably at right angles to it, as indicated 
by the pressure decreasing from Jersey to Limerick: immediately on the 
transit of this crest the barometer fell at the three stations; the greatest fall 
<Krcunred at Jersey; the next in order was at lleUtone, and the smallest at 
Limerick*. The passage of this crest U clearly traced towards the north¬ 
east. The posterior slope of the wave over which this crest jjassed is u el 
seen from the observations at the following stations: — 
Jersey. llamsgate. 
Helstone. London. 
Limerick. Largs. 
Stornoway. 
During the passage of this crest, and Indeed nearly throughout the whole 
of the transit of the gre-at wave, the barometer at St. Vigean's was supe¬ 
rior to those at all the northern stations. The barometer at Newcastle was 
also superior to that .nt Helstone, with only one exception, during the same 
period. This is exhibited in the following Table, in which the readings of 
both barometers have been reduced to the level of the sea. 
Table VI. 
Barometric altitudes and diflerences observed at Newcastle-upon-Tyne, 
Northumberland, and Helstone in Cornwall, during the transit of the Great 
.Symmetrical Wave of November I84fi. 
Epoch, Nov. 
Hcl- 
■tone. 
Nkw- 
CMtlC. 
Now- 
ca*tle i. 
Epoch, Nov. 
HrJ. 
•tone. 
Nw* 
casUc. 
New¬ 
castle ±, 
2. 9 A.M. 
29791 
29-934 
-i--I3S 
1 10. 3 P.M. 
30-310 
30-5.18 
+•248 
3 p.u. 
7(itl 
•89.1 
-f-W.") 
9 P.M. ... 
•287 
-.179 
+•292 
9 P.M. 
•8i5(i 
•881 
4--023 
11. 9 A.M . 
•278 
,•547 
+ ■271 
3. 9 A.M . 
•891 
-948 
+•055 
8 P,M. 
•266 
•512 
+■246 
3 P.M. 
•983 
•984 
+•0.33 
9 P.M . 
•295 
•53.3 
+•238 
9 P.M. 
•943 
29'fl.’57 
+•014 
13. 9 A.M . 
•342 
•543 
+•201 
4. 9 A.M. 
39-92(1 
30117 
+ •191 
3 P.M. 
■327 
•5U 
+•217 
9 P.M . 
30(184 
-033 
-049 
9 P.M. 
•329 
•561 
+•232 
fi. 9 A.M..... 
-03(1 
•178 
+•143 
13. 9 A.M . 
•323 
•522 
+ 199 
3 P.M. 
■003 
177 
r ^ 
+•175 
3 P.M. 
•354 
•472 
+•218 
9 P.M . 
•OlH 
•190 
+ •172 
9 r.M. 
•289 
•453 
+•164 
3. 9 A.M. 
•021 
'205 
+•184 
14. 9 A.M. 
•198 
•392 
+•194 
3 P.M. 
•02G 
18.1 
+■1.19 
3 P.M. 
-156 
•448 
+•290 
9 P.M. 
•058 
•318 
+•1.18 
9 P.M. 
•1*21 
•343 
+-222 
y. 9 A.M . 
•199 
•243 
+ •074 
15. 9 A.M . 
30021 
•271 
+•250 
3 P.M. 
•19.1 
•354 
+•0.19 
3 P.M. _ 
29-986 
•222 
+•236 
9 P.M. 
•239 
•28.1 
+•038 
9 P.M. .... 
30-028 
•227 
+•199 
8. 9 A.M. 
•30-2 
•420 
+•1)8 
18. 9 A.M . 
29-981 
•181 
+•200 
3 P.M . 
•291 
•433 
+-1.'19 
3 P.M. 
•885 
•105 
+■220 
9 F.M . 
•324 
•478 
+•154 
9 P.M. 
•825 
30014 
+•189 
9. 9 a.m..... 
•3.39 
•540 
+•201 
17. 9 A.M. 
•705 
29*824 
+ 119 
3 P.M . 
•333 
•MS 
+ •301 
3 P.M. 
•799 
•681 
-•118 
9 P.M. 
•379 
-.159 
+•180 
41 u u 
■869 
•784 
—•085 
10. 9 A.M. 
•331 
•594 
-f-2G3 
1 
* The point marked • in fig. 8 indicates this crest. 
