"The change of the moon," the expression in general use in predictions of the weather, is idly and inconsiderately used by educated people, without considering that in every phase that planet is the same to us, as a material agent, except as regards the power of reflected light; and no one supposes that moonlight produces wet or dry. Why then should that point in the moon's course, which we agree to call "the new" when it begins to emerge from the sun's rays, have any influence on our weather. Twice in each revolution, when in conjunction with the sun at new, and in opposition at the full, an atmospheric spring-tide may be supposed to exist, and to exert some sort of influence. But the existence of any atmospheric tide at all is denied by some naturalists, and is at most very problematical; and the absence of regular diurnal fluctuations of the barometric pressure favours the negative of this proposition. But, granting that it were so, and that the moon, in what is conventionally called the beginning of its course, and again in the middle, at the full, did produce changes in the weather, surely the most sanguine of _rational lunarians_ would discard the idea of one moon differing from another, except in relation to the season of the year; or that a new moon on the Sabbath day, whether Jewish or Christian, had any special quality not shared by the new moons of any other days of the week. Such a publication as "N. & Q." is not the place to discuss fully the question of lunar influence. Your correspondent J. A., JUN., and all persons who have inconsiderately taken up the popular belief in moon-weather, will do well to consult an interesting article on this subject (I believe attributed to Sir D. Brewster) in _The Monthly Chronicle_ for 1838; and this will also refer such inquirers to Arago's _Annuaire_ for 1833. There may be later and completer disquisitions on the lunar influences, but they are not known to me. M. * * * * * ROCOCO. (Vol. i., pp. 321. 356.)