THE MOON AND THE WEATHER. 481 



the clouds is increased radiation from the earth's surface, producing a 

 reduction of temperature in the air near the ground ; and ilr. Park 

 Han-ison, who discussed a series of temperature observations made at 

 Oxford, Greenwich, and Berlin, found a mean decrease of more than 

 S'^ F. about the time of full moon. The French proverb of la lune 

 rousse, which Louis XVIII bewildered Laplace by asking him to ex- 

 plain, may be accounted for by the aid of these researches. The name 

 of "red moon" is applied to the moon which is full at the end of 

 April or early in May, because during the clear nights which then pre- 

 vail, the tender leaves and buds are frozen and tui'n red ; and popular 

 superstition attributes this effect to the peculiar action of the "red 

 moon's "rays. It is at least curious that the connection assumed in 

 this superstition between the full moon, clear nights, and May frosts 

 should be one that is suggested by independent scientific results. 



Apart from any question of lunar influences, however, there are 

 many popular prognostics which make use of the moon merely as a 

 convenient exhibitor of certain atmospheric effects — effects which 

 would not be visible without the moon to show them up, but in the 

 production of which that orb plays no part whatever ; and in so far 

 as sweeping denunciations of lunar weather proverbs include these, 

 discredit is thrown on a class of useful sayings very unjustly. 



There is, perhaps, no better known lunar prognostic than that re- 

 ferred to in the old Scotch ballad of Sir Patrick Spens : 



" ever alack ! my master dear, 



I fear a deadly storm. 

 I saw the new moon late yestreen, 



Wi' the auld moon in her arm ; 

 And if ye gang to sea, maister, 



I fear will suffer harm." 



Chambers, in " The Book of Days," says that to see " the old moon in 

 the arms of the new one " is reckoned a sign oifine weather — another 

 curious example of how sayings get twisted ; but in that statement he 

 is quite wrong. The appearance is almost universally held to be a 

 sign of bad weather. Two explanations have been offered to account 

 for the prognostic, in each of which there is undoubtedly a measure of 

 truth. When the moon appears " new " to us, the earth would appear 

 " full " to the lunar inhabitants, if there were any ; and what causes 

 the dark part of the young moon to be dimly visible is its reflection of 

 the brilliant earth-shine. The earth, however, will not always shine 

 v/ith equal brilliance, even when the same amount of surface is illu- 

 minated, for obviously clouds reflect more light than either land or 

 sea. Hence, when an unusual illumination of the night-side of the 

 moon is apparent, it shows that the earth-shine is exceptionally strong, 

 which in turn is an indication of the presence of a large amount of 

 cloud in our atmosphere. Further, as a moment's consideration will 

 prove, the cloud area must lie to the west of us, the direction from 



VOL. XXXII. 31 



