REPORT ON FORESTS. 159 



chargeable mainly to the decreasing size of the catchment, and 

 'not to deforestation. 



There is nothing in the history of floods on the rivers of the 

 State which can be accepted as proof that there has been an 

 increase in the height to which they rise, excepting such 

 increase as may be accounted for by the building of dams, rail- 

 road embankments and other artificial obstructions which inter- 

 fere with the discharge. 



On the Delaware we have records of a great flood in 1692 

 which had not been equaled up to 1765. (Smith's History, 

 Chap. XII.) This is said to have been due to the melting of 

 snow. Another great flood occurred in 1786, the height of 

 which is recorded, and of which we estimate the volume at 

 Lambertville to have been 175,000 cubic feet per second. In 

 1801, 1836 and 1839 there were floods reaching from 140,000 to 

 150,000 cubic feet per second. On January 8th, 1841, a disas- 

 trous flood occurred which reached 255,000 cubic feet per second. 

 June 8th, 1862, there was another of about 224,000 cubic feet 

 per second. Other floods since 1841 have not reached as high a 

 point as that of 1862. There is certainly nothing in these 

 records which clearly indicates any progressive increase in the 

 volume of floods, but it appears to be true that the number of 

 floods of from 150,000 to 175,000 cubic feet per second are more 

 frequent than they were formerly. The history of this stream 

 is important, because deforestation on the large portions of the 

 catchment lying in Pennsylvania and New York continued 

 down to a more recent date than in New Jersey. 



On the Raritan there have been four great floods during the 

 century, namely, those of November 24th, 1810, July i7th, 1865, 

 September 24th, 1882, and February 6th, 1896. So near as we 

 have been able to ascertain, the flood of 1810 and that of 1882 

 were of very nearly equal volume, while that of 1865 was a 

 little lower, and that of 1896 was considerably higher than any 

 of the others. Bearing in mind that deforestation was progres- 

 sive on the Raritan up to about 1860, but has not increased 

 since that time, it is clear that here also there is no evidence 

 that deforestation has been accompanied by an increase in the 

 height of floods. The same is true of the Passaic, on which 

 there is no record of a higher flood than that of September, 1882. 



