394 Meteorological Tables. 



5. '—Meteorological Tables. By M. Jules be Walles- 

 TEiN, Corresponding Member of the Academy of History of 

 Madrid, and Secretary to the Russian Legation at Washing- 

 ton. — We have received a memoir, extracted from the Trans- 

 actions of the American Philosophical Society, in illustration 

 of the tables mentioned in the title of this article. 



M. Wallestein's observations were made between the l7th 

 of April, 1823, and the -i4th of April, 1824, with the thermo- 

 meter, the barometer, and the hygrometer; and his results, 

 obtained by great care, are obviously valuable, especially as 

 such observations are far from being sufficiently multiplied in 

 this country. 



Those diurnal and semi-diurnal tides in the atmosphere, 

 whose regular occurrence within the tropics has been fully 

 established by the observations of Humboldt and others, and 

 whose existence, in temperate latitudes, although with lessdis- 

 tinctness and regularity, has also been proved, have been as- 

 certained by M. Wallestein to exist at Washington. 



In this city, it appears that the maximum of the barometer 

 is at 9 A. M. and its minimum at 4 P. M. ; although the fluc- 

 tuations of the barometer are far from being as regular here 

 as within the tropics. M. Wallestein found that the mean 

 temperature of the months of May, June, and July, was almost 

 exactly the same as that of the three preceding months. 



The greatest difference of temperature was between Octo- 

 ber and September, and the least between August and 

 July. 



The mean temperature of the year was 58.5 Fah. 



of summer, 67.5 > Difference 



of winter, 47.9 J 19.6. 



The mean height of the barometer for 



the year was 29 922 



during summer, 29.910 > Difference 



during winter, 29 926 \ 0016. 



In 182.0, the maximum temperature observed at St. Peters- 

 burgh, Aug. 7, was 78.1 Fah. at noon. 



In 1822, in July, 85.1 Fah. at noon. 



At Washington, in 1823, the maxinnim temperature at 

 TQOon was 95.9 Fah. 



In 1820, at Petersburgh, Jan. 18, in the evening, the great- 

 est cold was — 2&,4 Reau. 



In 1823, Jan. 11, —14.2 



An 1824, at Washington, the greatest cold was 4-U.3 Fah. 



