352 
REPORT— 1847. 
The return of the November wave in the year 1846 occurred underrert 
dis8imi[ar circumstances to any that have been noticed in former years, aid 
wlien contrasted with Us transit in 1842, is extremely remarkable. Thebi" 
rometcr at London maintained an elevation above thirty inches from theSSd 
of October until the 16th of November, boUx inclusive, with a verj sli^ 
deprwsion (*012 only) below thirty inches on the afternoon of the 2Dil,lh 
|M*rirxl of the commencement of the wave. About 9 a.m. of the 17th,«k 
uicrcuriol column had slightly dcsccncleil below thirty inches, so that the dt* 
vciopmccit of the wave at London ww aUogether above thirty imhet. h 
J8-j%3 the crest was scarcely elevated above this line. In consequenceoftl* 
fHxculiarity the London curve w jiat compared with those of former ye^^ 
the altitude scarcely exceeding half an inch; tlnjse circumstances, in conmiia 
with the usual character of tlie weather attendant on an elevated mercnriii 
column, and the absence of strong gales of wind at the commencement ad 
closu ol the wave, had no small tendency to mask it in the south-taslem ptw 
of our island. The projected curve however strikingly develops iuesw- 
txol features. 'Yhejive subordinate waves, of which the great wave Ucon' 
posctl,^ are well seen, although the inflexions are not strong', the ccntralK 
crowning wave at London occupied/?;.•£ days; the subordinate wavrsondi 
anterior slope a little more than a and a half each; the wave that !*• 
mediately followed the central wave exhibited a greater dovelopmeut, iavini 
an amplitude ofdays; atid the closing subordinate wave a 
atilf. Iho epoch of transit, November 9th, was slightly earlier than iniui' 
but sulTlciuiitly near to regard these movements as a decided return c* ^ 
Wave, and strictly in accordance with the type as expressed in iiiy last report' 
Previous to procoerling with the examination of the observations recfhfi 
I beg to solicit the attention of the Association to the principle tliatIhiJ 
down in iny last report, namely, that a barometric curve, inemding a 
piety rww and fall at any one station, does not represent the form of wj 
n*ality in nature. The peculiar combination of barometric ascents aaJ oe- 
scents oceumng about this period of November, and exhibiting areinafks^r 
**P-?*”**^*'’J^^^ under very diverse circumstances and with 
i crent barometric altitudes, is a phamomeuon that appears to 
oxjdaiiation In the crossing of various systems of atmospheric waves or cW* 
rent^ Ihe south-eastern portions of ouV island have generally presenu*!*''' 
most syiuinctrical curves; aud tliis circumstance, connected with the conste!'' 
ecreasc of oscillation from the north-west, appears to indicate that shout 
IS par of the year, whatever may be the volumes of the ludividBol »■*'** 
o pressure, however they may be affected with regard to velodty, or n>*J 
c uperposed on much more extensive normal wares, the two syrfeo*^ 
' other in their respective progressions towards the north-east aw 
ou as to produce by their combined effects the barometric 
m. na (so far as regards the curve) x ally observed. In the following noticrt 
e olwervations, the term wave will be restricted to the prolubemflW* o" 
uie symmetrical curve. 
The most symmetrical curve has been obtained from observations 
n 1 ,^’orcupine, under the superintendence of Capfaia Fre 
nnfuri The wave commenced off* Walmer on the 2ndt coIbu' 
thn vl° being in Ramsgate harbour, and terminated'"' 
rani.i r II in Dover harbour. This curve is characlerited by* 
wivrt ^ i’ '' o21 immediately upon the culmination of the 
Smin^ ^>®t«'ecn9A.M. ofthelOth.and3p.M.oftheIltli. A 
occurred (mthc^fsd^^ subordinate wave on the posterior slopf- 
o highest reading of the barometer in the series occurred at St- Vigea*'* 
