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APPEARANCES AND INFLUENCES OF THE MOON. 



BY M. ARAGO OF THE FRENCH INSTITUTE*. 



According to Aratus, if, on the third day of the moon, the horns of 

 the crescent are sharp and well defined, the sky will continue serene 

 during the whole of the month. In reality, when the moon in the 

 evening begins to disengage herself from the sun's rays, she has always 

 the form of a crescent, terminated by two very sharp horns ; but if the 

 atmosphere happen to be troubled, the horns appear enlarged. This 

 enlargement, however, is a mere optical illusion, and is occasioned by 

 strongly illuminated clouds, in apparent contact with the moon, and 

 seeming to form a constituent part of her body. The fine extremities 

 of the crescent are then lost, as it were, in the parasitical light which 

 surrounds the moon, and become invisible to the naked eye. All this 

 is rendered evident by employing a telescope, which destroys the 

 illusion. 



It is generally believed, especially in the neighbourhood of Paris, 

 that the moon in certain months has a great influence on the phenomena 

 of vegetation. They give the name of red moon, (lune rousse) to the 

 moon, which, beginning in April, becomes full either about the end of 

 that month, or more usually in the course of May. In the months of 

 April and May, the moon, according to them, exercises a pernicious 

 influence on the young shoots of plants. They maintain that they have 

 observed during the night, when the sky is clear, the leaves and buds 

 exposed to this light to become red, that is to say, to be frozen, although 

 the thermometer, in the free atmosphere, stood several degrees above 

 the freezing point. They also assert, that if the rays of the moon are 

 intercepted by clouds, and thereby prevented from reaching the plants, 

 the same effects do not take place, under circumstances perfectly 

 similar in other respects with regard to temperature. These phenomena 

 seem to indicate that the light of our satellite is endowed with a certain 

 frigorific influence, yet, on directing the most powerful burning-glasses 

 or the largest reflectors towards the moon, and placing the most deli- 

 cate thermometer in their foci, no effect has ever been observed which 

 could justify so singular a conclusion. Hence, with philosophers, the 

 effects of the April moon are now referred to the class of vulgar pre- 



* Anmiaire pour 1833. 



