REPORT ON FORESTS. 171 



This table is believed to show quite accurately the changes of 

 rain-fall in New Jersey, taken as a whole, during the last seventy- 

 five years, and the tendency to progressive increase from 1825 to 

 1869, with only minor fluctuations, is apparent. It is also evi- 

 dent that the rain-fall is greater during the last half of this 

 period. Thus, during the quarter century from 1825 to 1849, 

 the average is 41.69 inches, while for the next twenty -five years, 

 to 1874, it is 46.71 inches, and for the last quarter century it is 

 ■45.42 inches. The showing of these records is clearly against 

 the hypothesis that deforestation is accompanied by a decrease 

 of raiurfall, because there was correspondingly greater deforesta- 

 tion during the quarter century from 1850 to 1874 than during 

 the previous quarter century, while the rain-fall was more than 

 five inches greater. In the same way, taking the State as a 

 whole, there was certainly as much forest during the last quarter 

 century, from 1875 to 1899, as during the previous one, although 

 the average rain-fall is 1.3 inches less. The other rain-fall 

 records of the State are too short to enable us to draw safe con- 

 clusions. 



Turning to the temperature records, we find that the Phila- 

 delphia record goes back to 1790, and from this date up to 1820 

 the temperature is below the average, while it ranges somewhat 

 above from 1820 to 1830. There is another low period from 1830 to 

 1840, after which time it continues generally above the average 

 until 1884, reaching another minimum in 1885. During the 

 whole period there is undoubtedly an upward tendency in the 

 temperature of Philadelphia, but it is difiicult to draw safe con- 

 clusions from a comparison of the early and later records, owing 

 to a difference in instruments and methods. We do not find 

 in the records of temperature anything from which safe con- 

 clusions may be drawn as to the eSect of deforestation in 

 the State. Unquestionably the temperature of Southern New 

 Jersey is affected much more by the sea than by the pine forests, 

 but our personal experience is to the effect that the mild and 

 salubrious winter climate of this region is to a great extent due 

 • to the presence of the pine forests and the sandy soil, which 

 together produce an unusually dry atmosphere for a climate 

 which is so much influenced by the sea. We believe that the 

 entire destruction of these pine forests would result in a much 



