CHAP. 9. AND PRESSURE. 249 



There is yet another observation on the 

 Barometer worthy of record. It is said, that if 

 a number of daily observations be taken, the 

 average maximum for any period will be found 

 to take place at noon, and the minimum at 

 nine o'clock in the morning, and the next 

 lowest at six in the evening. 



I introduce the above circumstances here, 

 merely that they may become the subjects of 

 the future observations of meteorologists in 

 different places ; as I think they are worthy of 

 stricter examination than has hitherto been 

 made.* 



* If the place of the Moon has such an effect on the 

 atmosphere, as to influence the barometrical pressure, it may 

 probably produce other varieties in the state of the air, which 

 may influence the nervt>us system and animal functions of 

 persons in particular kinds of disease. It is thus that it may 

 have an effect on persons of such deranged intellect, as is 

 termed lunacy, who are said, in some cases, to be worst about 

 the full of the Moon. 



There are many other instances of periodical paroxysms of 

 different complaints, and some of them very curious; but 

 how far, and in what manner, solar and lunar influence is 

 concerned, cannot be precisely determined. Some persons 

 have had paroxysms come on at particular hours of the night, 

 and have, for a long time, awoke at those hours. To try 

 how far the imagination has been concerned in producing the 

 diseases, clocks have been altered to deceive the patient, but 



