36 REPORT—1848. . 
that portion of the desiderata having reference to the seasonal barometric 
types ; and thirdly, by noticing any results that may have been obtained during 
the past year of a character notcontemplated or but slightly indicated in our 
former reports, and which have more particularly originated in the observa- 
tions of the last return of the November curve. 
Table I. exhibits the waves already recognized with references to the re- 
ports in which their elements, &c. are given in detail. 
The waves designated Nos. 1 and 2 in this table passed over Western 
Europe during the early part of November 1842. In reporting progress 
at the last Meeting of the Association, I stated that an examination of the 
observations made during the first eight days of November over an area 
extending from Ireland to St. Petersburgh and Geneva, appeared upon the 
hypotheses either of waves or of parallel currents, fully capable of explain- 
ing all the barometric movements during those eight days (Report, 1847, 
p- 370). In the remarks which immediately follow, this explanation will 
form a prominent feature, as the variations of pressure during the period just 
referred to will be traced, especially over Western Europe, and will receive 
considerable elucidation from observations made at Alten in Finmark, with 
which I have been kindly furnished by Dr. Lee. 
In the former reports which I have had the honour to present to the As- 
sociation, I have very briefly glanced at two important points connected with — 
these waves, the great extent of suriace which they cover, and the opposite 
barometric phenomena produced by the transits of slopes of an opposite cha- 
racter. In my report for 1846, p. 163, when enunciating the desiderata that 
then presented themselves, allusion was made to the direction of the crest ; and 
there appeared to be some difficulty in finding a point on the earth’s surface in 
reference to which we could positively pronounce that a crest—which clearly 
existed in a certain direction, in another locality not very far removed from — 
it—had so completely thinned off, and become so distinctly terminated in a — 
longitudinal direction as to exert no influence on the barometer. Such phe- 
nomena are not exhibited in the British Islands, and it is likely they are but 
seldom met with in Central Europe. We must, as remarked on a former 
occasion, extend our area of examination ere we can obtain phenomena that 
will enable us distinctly to say that a wave existing in one locality does not 
exist, or in any way make itself felt in another. 
The area of examination having reference to the discussion of the baro- 
metric and anemonal phenomena during Nov. 1842, which forms the second 
part of my report, 1846, pp. 132 to 162, is principally confined to the British 
Islands; there are two stations forming the eastern limits of this area, which, - 
with regard to Great Britain and Ireland, may be considered as outliers; they 
however enable us to carry forward our investigation by tracing onwards _ 
towards the north-east and east those barometric movements the nature of 
which the proximity of the British stations has greatly contributed clearly to 
define, so that they can be readily recognized at stations considerably re- _ 
moved from each other: these stations are Christiania and Paris. By com- 
bining with this discussion observations at St. Petersburgh and Geneva oun 
area is still more enlarged, and we are enabled to form a much more accurate — 
notion of the real extent of the waves and of the phenomena resulting from 
them. By still further enlarging our area of examination, our knowledge — 
must necessarily become more defined and our conceptions more distinct 5 
we shall be prepared to seize on relations which at first may not be apparent, — 
owing particularly to the decided want of similarity between the phzenomena — 
acetone SS 
a Re as ee 
a 
rte \ pirate. 
ek ee 
