GEOGRAPHY AND ANTIQUITIES. 383 



being good for small vessels. At some distance from the entrance 

 a hard red iron-ore-like reef across the river exists, but a passage 

 between may be found. My crew consisted of natives of the coast of 

 Zanzibar, who stood the fatigue well." Capt. Short estimates the dis- 

 tance which he sailed up the river to be about 210 miles frofti its 

 mouth, bearing about from west-north-west to north-west. From that 

 point, the white-topped mountains bore to the southward of west 

 a little, distance about 60 miles. 

 i 



INFLUENCE OF THE MOOX UPON THE CLOUDS. 



The following paper was read at the Cleveland meeting of the 

 American Association, by Prof. E. Loomis. 



Sir John Herschel, in his " Outlines of Astronomy," page 261, has 

 the following remarkable language : " The heat of the moon is much 

 more readily absorbed in traversing transparent media, than direct 

 solar heat, and is extinguished in the upper regions of our atmos- 

 phere, never reaching the surface of the earth at all. Some proba- 

 bility is given to this by the tendency to disappearance of clouds under 

 the full moon, a meteorological fact, (for as such we think it fully enti- 

 tles to rank,) for which it is necessary to seek a cause, and for which 

 no other rational explanation seems to offer." In a note on the same 

 page, he informs us that this fact rests upon " his own observations, 

 made quite independently of any knowledge of such a tendency hav- 

 ing been observed by others." Humboldt, however, in his personal 

 narrative, speaks of it as well known to the pilots and seamen of 

 Spanish America. 



Having made a pretty extensive comparison of observations several 

 years since, for the purpose of determining the influence of the moon's 

 phases upon the fall of rain, I was led to distrust the preceding conclu- 

 sion of Sir John Herschel, and have accordingly sought for observa- 

 tions by which its accuracy might be tested. For this purpose, I 

 turned to the Greenwich Meteorological Observations, where we find 

 the amount of cloudiness of the sky recorded every two hours, night 

 and day, for a period of some years. I arranged all the observations 

 in a tabular form, showing in one column, the average amount of 

 cloudiness on the day of each full moon for the whole period ; the 

 second column shows the amount of cloudiness on the day after full 

 moon ; the succeeding columns show the degree of cloudiness on the 

 second day after full moon ; the third, fourth, etc., days up to the last 

 quarter ; and other columns show the cloudiness for days preceding 

 the full. In the accompanying table, in like manner, the observations 

 are arranged for new moon, and also for the preceding and following 

 days. I then took the average of all the numbers in each column 

 and obtained the following results : 



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& * -- 







