REPORT ON FORESTS. 169 



The light rain-fall of the Raritan valley is somewhat accentuated, 

 but in the Highlands it appears that the deforested portions 

 have as much rain-fall as those more heavily forested. The 

 influence of the sea upon the temperature in summer is marked, 

 while the variations due to elevation, in the northern part of the 

 State, are much the same as shown in Plate XI for the year. 



Plate XIII exhibits the winter temperature and the rain-fall 

 from October to March, inclusive. In this case the rain-fall pre- 

 sents a distribution a little different from that of the growing 

 months, but, comparing the two periods, there is nothing to war- 

 rant the inference that it is in anywise effected by forests. 



The result of these studies must be regarded as demonstrating 

 that the records of rainfall and temperature fail to show any dif- 

 ference in climate between forested and deforested portions of the 

 State which may with confidence be ascribed to the influence of 

 the forests. 



We have also analyzed the longer rain-fall records of the State, 

 and of New York and Philadelphia, to see if there has been any 

 change in the rain-fall which may be due to change in the 

 forests. Plate XIV is a series of diagrams showing the rain-fall 

 at New York, Newark, New Brunswick, Trenton and Philadel- 

 phia. The Trenton record is combined with one at Morrisville, 

 Pennsylvania, just across the Delaware. The Philadelphia record 

 goes back to 1825, ^"^ so does the Morrisville-Trenton record, 

 although the latter is missing for certain years. The New York 

 record begins with 1836, that of Newark with 1843, and that of 

 New Brunswick with 1854. New York is so much within the 

 influence of the ocean that it can scarcely be expected to show any 

 eflect due to forests, but this fact makes the record valuable for 

 comparison with the stations more inland. The diagrams show 

 that from 1836 to about 1868 the rain-fall at New York was 

 steadily increasing, but at the latter date it suddenly fell off and 

 remained below the average until 1883, since which year it has 

 been fluctuating. The Newark record is very similar to that of 

 New York, while the New Brunswick, Trenton and Philadelphia 

 records vary in certain particulars from the other two, princi- 

 pally in showing larger rain-fall from 1868 to 1873. ^^ '^i^^ ^^ 

 seen that, as a rule, rain-fall was increasing at Newark and New 

 York, while deforestation was progressing "in the northern part 

 of the State. We have stated that this deforestation was at a 



