646 FOREIGN CORRESPONDENCE. 



FOREIGN CORRESPONDENCE, 



Paris, December 2, 1877. 



The belief that the moon exercises an influence on our atmosphere is as 

 old as tradition itself. Astronomers of late appear to maintain the contrary. 

 M. Faye, for example, a most eminent authority, asserts that the moon is 

 innocent of all changes in the weather, despite the experience of peasants 

 and sailors. Now, there is much to be said on both sides, and the subject is 

 perhaps not quite exhausted, as we shall see. If the moon, observe the 

 generality of people, exercise an influence on the tides, why not on atmos- 

 pheric currents, equally as movable? Now, the moon can only act by its 

 attraction or its heat; bodies attract in proportion to their masses, etc., so 

 that the moon ought less influence a lighter body, such as air, than a heavi- 

 er, like water. The influence of the moon at the equator does not raise the 

 water of the ocean more than 39 inches. What we call the tide, that is, 

 where the sea rises from 20 to 50 feet along the coast lines, is not due to 

 the action of the sun and moon, but to the mass of water rolling in from the 

 ocean, bathing the shores and penetrating into recesses, and which being 

 unable to find an issue proportionate to its volume, becomes, as it were, 

 heaped up ; increases in height, for what is lost in breadth is gained in ele- 

 vation. The barometer does not register any appreciable difference in atmos- 

 pheric currents, due to the moon's influence ; when this satellite passes 

 over our heads it lightens bodies one ten millionth part of their weight. 

 The moon's heat is insignificant ; according to Piazz^i Smyth, only equal to 

 that of a candle at a distance of 40 feet. So much for theory. It is a gen- 

 eral opinion, prejudice, if you please, that the moon has an influence on the 

 production of rain. Shrewd observers say more rain falls during the sec- 

 ond, than pending any other quarter of the moon, and when the latter's or- 

 bit is near, than when distant from the earth. Arago, contrary to what is 

 believed, confirms the popular opinion within certain limits. The effects of 

 the moon are general; the same day that it rains at Paris, it is beautiful 

 weather at Orleans — yet our satellite is the same for both cities. There are 

 no storms at Lima, and never at St. Helena, the other side of the Atlantic, 

 is thunder heard ; there are peals of thunder every day in the Moluccas 

 and the Sonde islands, yet the moon in these regions passes through its phases 

 as with us, and the ocean rises or falls, following the moon, 



It is known that the tides of oar atmosphere are insignificant ; even so, 

 are they capable of producing rain and fine weather? Clearly, there can be 

 no rain without water, and no matter to what altitude the moon might 

 draw up the atmosphere, not a drop of rain could fall if it did not already 

 exist there. Bear in mind a volume of air can only contain a quan- 

 tity of watery vapor proportionate to a given pressure and tempera- 

 ture. If the air expands by heat, or contracts by cold, the excess of vapor 

 falls as rain. Currents of air coming from the ocean are charged with wa- 



