With respect to the great wave of November, our knowledge of it would be
much increased by such a series of observations as mentioned above,
being made on board surveying and other vessels employed off Scotland
and Ireland; vessels navigating the North Sea; vessels stationed off the
coasts of France, Spain, Portugal, and the northern parts of Africa, and
at all our stations in the Mediterranean. In this way the area of
examination would be greatly enlarged, and the _differences_ of the
curves more fully elucidated; and this extended area of observation is
the more desirable, as there is some reason to believe that the line of
greatest symmetry _revolves_ around a fixed point, most probably the
nodal point of the great European systems.

It is highly probable that movements of a somewhat similar character,
although presenting very different curves, exist in the southern
hemisphere. The November wave is more or less associated with storms. It
has been generally preceded by a high barometer and succeeded by a low
one, and this low state of the barometer has been accompanied by stormy
weather. We are therefore prepared to seek for similar phænomena in the
southern hemisphere, in those localities which present similar states of
weather, and at seasons when such weather predominates. We have already
marked out the two capes in the Southern hemisphere for three-hourly
observations: they must doubtless possess very peculiar barometric
characters, stretching as they do into the vast area of the Southern
Ocean. It is highly probable that the oscillations, especially at some
seasons, are very considerable, and vessels visiting them at such
seasons would do well to record with especial care the indications of
the instruments already alluded to. At present we know but little of the
barometric movements in the Southern hemisphere, and every addition to
our knowledge in this respect will open the way to more important
conclusions.