220 EIGHTEENTH ANNUAL REPORT ON THE STATE CABINET. 



The extremes of cold have been greatest in the last half of the years of 

 observation. This may be only the common varying change, and to be the 

 contrary in the next 28 years ; but is more probably due to the clearing off 

 the forests, and exposing the country to the more powerful action of cold. 

 When these observations were begun in 1837, the original forest stood on a 

 great part of the land now in the city limits of Rochester. The change has 

 been very great and extensive over Western New- York, in the removal of 

 the forests. Noah Webster long since showed, in his Essay on Climate, 

 the operation of this change, viz. to make the heat of autumn later, and also 

 the cold of spring later ; to freeze the earth to greater depth, and delay the 

 advance of heat later in the spring ; and to produce greater changes in the 

 temperature. 



To obtain these tabular results has taken in 28 years, with the leap-years, 

 10227 days ; three observations a day, 30881 observations ; one-third the 

 sum of each day, besides the means of each half month and whole month, 

 and of each year, etc. No wonder so few apply their time and study to such 

 a stupid round, yet essential to desired results. 



II. BAROMETER AND RAIN-GAGE. 



In the following Table are given the monthly average height, the highest and lowest 

 mean, the highest and lowest observation, and the range in the month, all for 27 

 years; the water fallen in the month, and the monthly average for 28 years. 



TABLE V. 







Highest 



Least 











Average 



Months. 



Mean. 



Mean. 



Mean. 



Highest. 



Lowest. 



Range. 



Water. 



28 years 



January . . 



29.39 



29.76 



28.81 



29.85 



28.61 



1.24 



2.91 



2.077 



February . 



29.29 



29.76 



28.84 



29.85 



28.76 



1.09 



1.18 



2.030 



March 



29.37 



29.72 



28.81 



29.77 



28.74 



. 1.03 



3.44 



2.077 



April .... 



29.41 



29.69 



29.14 



29.73 



29.12 



0.61 



3.23 



2.441 



May 



29.32 



29.63 



29.09 



29.63 



29.05 



0.58 



6.54 



2.987 



June 



29-52 



29.76 



28.97 



29.78 



28.87 



0.91 



1.57 



2.961 



July 



29.51 



29.73 



29.28 



29.74 



29.24 



0.70 



1.66 



3.325 



August . .. 



29.42 



29.67 



29.03 



29.68 



29.01 



0.67 



5.49 



2.816 



September 



29.45 



29.79 



29.14 



29.82 



29.08 



0.74 



i 1.83 



3.237 



October . . . 



29.33 



29.66 



28.86 



29.67 



28.78 



0.80 



i 5.51 



3.253 



November. 



29.40 



29.90 



28.65 



29.93 



28.48 



1.45 



' 2.66 



2.756 



December . 

 Mean. . . . 



29.31 



29.98 



28.83 



] 



30.04 

 Range of 



28.64 

 year 



1.40 



2.67 



2.510 



29.39 



1.56 



38.69 



32.470 



From this Table are deduced, 1° The height of the barometer for the 

 year, 29.39 inches, and its range in the year, 1.56 inch; 2° The water 

 fallen in the year, 38.69 inches, and the average of water for 28 years, 

 32.47 inches in depth. The water of 1864 far exceeds the average. 



The average height of barometer from 1838 to 1864 inclusive is 29.53 

 inches, with a range varying from 28.24 inches to 30.47, and making the 

 range of 2.23 inches for the 27 years. 



The water fallen has a higher interest, as is shown in the annual amounts. 



