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tlie opinion that the heat radiated from the moon has very little to do 

 with the changes of weather, Mr. Webb proceeds to say : — The following 

 facts, however, tend to the conclusion that the moon does exercise some 

 influence on the weather. From observations of temperature at Gx'een- 

 wich, Oxford, and Berlin, it has been shown "that a maximum mean 

 temperature occurs on the average at each of these places on the sixth 

 and seventh day of the lunation, and a minimum mean temperature 

 shortly after full moon." That is to say, when the moon's surface is most 

 heated, and the lunar radiation therefore greatest, the temperature at 

 these places is reduced. Certain theories wei-e based on these conclusions, 

 which were immediately overthrown by corresponding but quite contrary 

 facts, deduced from observations at St. Petersburg. A relation between 

 these two sets of observations has, however, since been determined by 

 the discovery that, at the former places, '- S. and W. winds increase in 

 frequency from new moon to the second octant, whilst in the last quarter, 

 the same winds are at a minimum, and 'N. and E. winds reach their 

 maximum." These circumstances are sufiicient to account for the 

 variations of temperature in the south of England and at Berlin, and, 

 from the knovv^n relations between the prevailing winds in the two 

 regions, at St. Petersburg also. Whether there is a relation between the 

 moon's age and these winds, or whether the observed facts are only 

 coincidences, cannot be said to be determined. Even if we take the 

 former view, we must remember that up to the present time this is all that 

 has been gathered as to the direct influence of the moon on the weather, 

 and that it does not connect any lunar phenomena with the occurrence 

 of storms, rains, and inundations, or lead us to conclusions as to the total 

 influence of the moon on any given day upon the weather all over the 

 globe. Neither Lhe efiects of lunar radiation, nor the supposed atmo- 

 spheric tides, if they do really exist, lend, therefore, any warrant to 

 Lieutenant Saxby's prediction. The moon, however, may have an 

 indirect efiect on the weather in a manner which does not yet appear to 

 have attracted the attention of meteorologists, viz., through the tides 

 themselves. It is an ordinarily received opinion that changes of wind 

 often take place at the time of slack water, either after the ebb or flow 

 of the tide. With regard to particular places, this is more than an 

 opinion — it is, I believe, a distinctly ascertained fact. On this point, 

 however, I am speaking from memory and from j)ersonal observation ; 

 there are no registers of scientific observations to fall back upon. In 

 Port Jackson, for instance, where there is steady fine weather with a 

 N.E. wind blowing in from the sea, if the time of slack water after flood 



