LUNAR CYCLES. 



that extremity of the orbit to the other end of the oval, her 

 distance continually diminishes until arriving at the other end, 

 it becomes least. These variations of distance are produced 

 every revolution of the moon round the earth. Now, owing to a 

 certain change of position, to which the moon's orbit is subject, 

 the points which mark her greatest and least distances are 

 subject to a slow, gradual, and regular change ; so that the points 

 in the heavens at which she reaches her greatest and least 

 distances are different every revolution. After the lapse, how- 

 ever, of eight years and ten months, these points having traversed 

 the whole circumference of the heavens, resume their former 

 position very nearly ; so that the actual times at which the 

 moon is observed at the same distances from the earth, and also 

 at the same points in the heavens, recur in a cycle, the length of 

 which is about eight years and ten months. 



So far, therefore, as the vicissitudes of the weather can be 

 supposed to be influenced by this cause, their period should be 

 such that, after the lapse of nine years, the corresponding states 

 of the weather would be as it were, two months in advance : 

 thus the effect produced in December, 1800, would again be 

 produced in October, 1809, in August, 1818, and so on. 



If the purpose be to determine the cycle in which the lunar 

 influence so far as it depends on distance, would produce the 

 same effects upon the same days of the year, the duration of the 

 cycle would be six times eight years and ten months : for in six 

 successive intervals of that period, there are exactly fifty-three 

 years ; but any less number of periods of eight years and ten 

 months do not make a complete number of years. Therefore 

 after a cycle of fifty-three years, the moon being on the same 

 day of each successive year at the same distance from the earth, 

 her influence, so far as depends on distances, will be the same, 

 and will produce the same effect upon the weather. 



5. Now we cannot better illustrate the loose and inaccurate 

 manner in which scientific principles are applied by some 

 meteorologists than by stating that this cycle of eight years and 

 ten months has formed the theoretical grounds for a reputed 

 meteorological period of nine years. It has been maintained that, 

 through every successive interval of nine years, the changes of 

 weather have a general correspondence : thus, if the state of the 

 weather throughout the year 1800 be examined, it has been said 

 to correspond with the weather throughout the years 1809, and 

 1818, &c. 



6. From all that has been stated, it follows, then, that 

 the popular notions concerning the influence of the lunar 

 phases on the weather have no foundation in theory, and no 



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