( 369 ) 



phases, from their mean. The numbers in the last column seem 

 lo indicate the existence of a very slight variation of the tem- 

 perature of the air dependent on the moon's phases, causing the 

 mean daily temperature during one half of the hmation to be 

 slightly high er than during the other half. The range of this 

 variation does not amount to 0°.1 C. 



The higher temperatures on the days about full moon may be 

 caused by heat radiated by the illuminated side of the moon, 

 facing ihe earth on these days. If this be really so, the mean 

 temperatures of the hours of the night on the di fleren t phases 

 of the moon will show a similar variation, but of grea ter range. 

 Therefore, the mean temperatures of the hours of the night, 

 7 p. m. to 5 a. in., on the eight different moon's phases, have 

 been calculated. The result is contained in Table IT. 



From this table it appears that if the mean temperature on 

 the days of full moon be really a little higher than on other 

 moon's phases, this is not caused by heat radiated from the 

 moon. 



Another cause of the higher temperature on the days about 

 full moon may be, that on these days the sky is clearer than on 

 other days, as has sometimes been suppo?ed. If this be really 

 the case, the mean temperatures on the hours of the clay will 

 show a variation dependent on the moon's phases, similar to that 

 shown by the mean temperatures of the twentyfour hours, but 

 of greater range. Therefore, the mean temperatures of the hours 

 of the day, 7 a. m. to 5 p. m., on the eight different moon's 

 phases, have been calcidated. The result of this calculation is 

 contained in Table TIL 



From this table it appears that if the mean temperature of 

 the twentyfour hours on the days about full moon be really a 

 little higher than on the days of the other moon's phases, this 

 is caused by the temperature of the day-hours on the days about 

 full moon being higher than on other days, which may be ascribed 

 to the sky being clearer on the days about full moon than on 

 other days. If this be really the case, the mean daily range of 

 the temperature must be greater on the days about full moon 

 than on the other moon's phases. Therefore, the mean daily range 

 of the temperature has been calculated for the eight different 



