Meteorolosrical Journal. 57 



^b 



not so strongly marked, varying but little from the preceding year. 

 The quantity of rain and melted snow amounts to forty two inches 

 and forty six hundredths ; being eight inches greater than that of 

 the year before ; and is nearly the mean annual supply for a series 

 of years in this part of the valley of the Ohio. The falls of snow- 

 have been light, not more than two or three inches at any one time. 

 But even a very shght covering of the earth's surface has a very 

 perceptible influence in diminishing the amount of heat radiated 

 from the earth. The mercury rarely sinks to zero when there is no 

 snow on the ground. In January, 1835, when the cold in New 

 Lebanon, N.Y. froze the mercury in the thermometer, and all through 

 the eastern States was of almost unprecedented severity, the depres- 

 sion at Marietta was at no time less than two degrees above zero, 

 and most of the time at 6° or 8°. . The earth was hare, and there 

 was a free radiation of heat from its surface. In February following, 

 under a different aspect, the earth being covered with snow, the 

 mercury sunk to 15° below zero, demonstrating at once the power- 

 ful effect of a checked radiation. Snow being one of the most per- 

 fect non-conductors of heat, and furnishing a much better material 

 for the winter huts of the inhabitants of the frozen arctic regions, 

 than wood, of which we have evidence in the Voyages of Parry and 

 Franklin. The temperature of April, which is esteemed in some 

 measure an index for the year, was 49°. 70 ; being nearly 6° less 

 than the temperature of the same month in the preceding year, but 

 nevertheless closely approximating to the mean of the current year, 

 which is 50°. 65. The blossoms of the peach and the pear were re- 

 tarded this spring to the 26th of April, and the apple to the 2d of 

 May ; whereas in common seasons the peach blooms the fore part 

 of the month, and the apple by the middle. The same retardation 

 in the ripening of fruits was continued through the season. The 

 " Drap d'or" apple and "Early Chandler," usually fit for eating 

 by the first of July, were not ripe until the middle of the month. — 

 Wheat harvest on the Ohio river, commences about the fourth of 

 July, and Rye the last of June. This season they were not fit for 

 the sickle until near the middle of that month, in the earliest fields, 

 and the harvest was continued until the last of the same ; the grain 

 ripening very unequally, and many of the heads partially or entirely 

 blighted, being destitute of seeds. This was probably owing to 

 some violence or injury inflicted on the pollen, by powerful rains, or 

 a hot sun after a thunder shower. Indian corn, or maize, requiring 

 Vol. XXX.— No. 1. 8 



