136 SCIENTIFIC AGRICULTURE. 



America more falls during night thaji during day. The mean 

 quantity of rain is less as we ascend above the sea level : it is 

 more in the same latitudes where the mean temperature is 

 68 F., than at any point above or below this. 



Rains become less periodical and regular as we leave the 

 equator. The mean annual quantity of rain in Europe, between 

 latitudes 35 and 50 north, (and probably the same would be 

 nearly true of similar latitudes in the United States,) is from 

 25 to 45 inches. 



The mean quantity, as shown by the report of the Regents 

 of the University of New York to the Legislature, for the last 

 ten or fifteen years, as measured at thirty different places in 

 this state, is 35.84 inches. Of these various estimates, 43.65 

 was the greatest number of inches, which fell at " Erasmus 

 Hall," Long Island: the smallest number was 28.14, which 

 fell in St. Lawrence county. We see from tables in Bous- 

 singault's work, that most falls in autumn and least in spring: 

 we see also that most falls in July and least in March of any 

 months in the year. 



This table is from the record kept ly L. Wetherell, Esq., at 

 the Rochester Collegiate Institute. 

 Greatest annual mean temperature for 13 years, ending 



with 1847, 3999 



Least do. - 25 46 



Greatest mean temperature of one year, - - 48 60 

 Least " " " - - 43 71 



Highest heat, July, 1845, - - 102 



Lowest " Feb., 1836, 8 below zero. 

 Most rain in one month, Oct., 1846, 6.79 inches. 



Least " " " Jan., 1837, 0.16 



DEW AND FROST. 



All bodies in nature are constantly undergoing a change of 

 temperature : however hot or cold a body may be, it is eon- 



