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be necessary would be of such a character as to affect 
materially the probability of a close connection between the 
daily variations of rainfall and the diurnal oscillations of the 
magnetic needle.” At a meeting of the Meteorological 
Society, held Nov. 20, 1867, the president, Mr. Glaisher, 
F.R.S., communicated a valuable and elaborate paper “ On 
the Hourly Frequency and Fall of Rain in connection with 
the Diurnal Changes of Magnetic Declination.” in which, 
after referring to the results of my discussion of Mr. Bates’s 
observations, he gives the results of a valuable series of hourly 
observations of rainfall made at the Royal Observatory, 
Greenwich during the six years 1861-66. The paper is 
printed in No. 83 of the “ Proceedings of the Meteorological 
Society,” and is accompanied by diagrams showing the fre- 
quency and amounts of rain for every hour in each year, 
and the mean frequency and mean amounts for all the years. 
There is also a curve showing the daily variations of mag- 
netic declination ; and, in comparing it with the curves of 
mean frequency and mean amount of rainfall, Mr. Glaisher 
remarks that “ there is a kind of agreement between the 
curve of frequency and that of the magnetic variation; but, in 
comparing it with that of the amount of rain, there is nothing 
similar in the two curves, and therefore there does not seem 
to be any connection between the diurnal movements of the 
declination magnet and the diurnal fall of rain.” In two 
papers since read to the Meteorological Society, one in 
January and the other in March of last year, Mr. Glaisher 
continues his discussion of the six years’ hourly observations 
of rainfall at Greenwich ; but he makes no further reference 
to the conclusion I had drawn from my discussion of Mr. 
Bates’s observations, and it would therefore appear that he 
still regards the results of the Greenwich observations as not 
affording any support to the view I had taken. Under 
these circumstances, I have thought it desirable to delay no 
longer in pointing out that, although the results of the 
