Professor Dove of Berlin has suggested that in the temperate zones the compensating currents of the atmosphere necessary to preserve its equilibrium may be arranged as parallel currents on the _surface_, and not superposed as in or near the torrid zone. His views may be thus enunciated:--That in the parallels of central Europe the N.E. current flowing towards the equator to feed the ascending column of heated air is not compensated by a current in the upper regions of the atmosphere flowing from the S.W. as in the border of the torrid zone, but there are also S.W. currents on each side the N.E., which to the various countries over which they pass appear as surface-winds, the winds in fact being disposed in alternate beds or layers, S.W., N.E., as in fig. 3. [Illustration: Fig. 3.] The Professor also suggests that these parallel and oppositely directed winds are shifting, _i. e._ they gradually change their position with a lateral motion in the direction of the large arrow cutting them transversely. In the course of the author's researches on atmospheric waves he had an opportunity of testing the correctness of Professor Dove's suggestion, and in addition ascertained that there existed another set of oppositely directed winds at right angles to those supposed to exist by the Professor. These currents were N.W. and S.E. with a lateral motion towards the N.E. He also carefully discussed the barometric phaenomena with relation to both these sets of currents, and arrived at the following conclusions. The details will be found in the author's third report, presented to the British Association for the Advancement of Science (Reports, 1846, pp. 132 to 162). During the period under examination the author found the barometer generally to rise with N.E. and N.W. winds, and fall with S.W. and S.E. winds, and that the phaenomena might be thus illustrated:--Let the strata _a a a' a', b' b' b b_, fig. 3, represent two parallel aerial currents or winds, _a a a' a'_ from S.W. or S.E., and _b' b' b b_ from N.E. or N.W. and conceive them both to advance from the N.W. in the first instance and from the S.W. in the second, in the direction of the large arrow. Now conceive the barometer to commence rising just as the edge _b b_ passes any line of country, and to continue rising until the edge _b' b'_ arrives at that line, when the maximum is attained. It will be remarked that this rise is coincident with a N.E. or N.W. wind. The wind now changes and the barometer begins to fall, and continues falling until the edge _a a_ coincides with the line of country on which _b b_ first impinged. During this process we have all the phaenomena exhibited by an atmospheric wave: when the edge _b b_ passes a line of country the barometer is at a _minimum_, and this minimum has been termed the _anterior trough_. During the period the stratum _b' b' b b_ transits, the barometer rises, and this rise has been called the _anterior slope_.