5o8 REPORT OF THE COMMISSIONERS OF 



In order to ascertain the mean temperature of the Upper Hudson drainage area I 

 have gathered all available temperature records, as for instance those of Albany, from 

 1825 to 1895, inclusive, a period of 71 years; Glens Falls, from 1879 to 1895, 

 inclusive, a period of 17 years; Keene Valley, from 1879 to 1895, inclusive, a period 

 of 17 years; Fairfield Academy for certain years from 1827 to 1849, i'l ^iH '9 years ; 

 Lowville Academy for certain years from 1827 to 1848, in all 19 years; Johnstown 

 Academy, certain years from 1828 to 1845, in all 14 years; Granville Academy, from 

 1835 to 1849, a period of 15 years; and Cambridge Academy certain years from 1827 

 to 1 841, making in all 14 years. The monthly means have been carried out as well as 

 the yearly means, giving as a yearly mean of all, 45.6'' F. A number of the 

 foregoing stations are, however, not in the Upper Hudson drainage area, but in 

 or near regions of similar elevation and general meteorological characteristics, and 

 without doubt represent very nearly the mean temperatures of the adjacent regions 

 actually lying within the Upper Hudson drainage area. Mean temperatures have also 

 been kept by the State Weather Service at Saranac Lake, and at a number of other 

 points either in or in the vicinity of the Hudson River drainage area. Tabulations of 

 the same are given in the Hudson Storage Survey reports. The mean temperature of 

 the Northern Plateau, as defined by the State Weather Service, and which includes 

 the Adirondack region, on and in the southern slope of which the Hudson River takes 

 its rise, has also been taken into account. The State Weather Service observations 

 only begin in 1889, and the period covered to date is therefore too short for final 

 conclusions. The record so far as kept at Saranac Lake indicates a mean temperature 

 there of 41° F. For tentative purposes the Northern Plateau may be taken at from 

 42 to 43° F. 



In order to obtain the mean precipitation on the Upper Hudson watershed, the 

 available rainfall data have been treated in a manner similar to that already described 

 for the mean temperatures, with the result of showing that for Albany, Glens Falls, 

 Keane Valley, Western Massachusetts, the Northern Plateau, Lowville Academy, 

 Johnstown Academy, Cambridge Academy, Fairfield Academy, Granville Academy, 

 and for a number of other places with short records not now specifically stated but 

 which may be found in detail in the reports, the mean rainfall is about 37.5 inches. 

 For the few years covered by the records of the State Weather Service the means are 

 about 40 inches, but the objection already stated to the unqualified use of short 

 temperature records applies with equal force to rainfall records. As regards both, the 

 general proposition is that we must gather data covering a sufficient number of years 

 to give a mean, which will not be essentially altered if we carry the observations to 

 any greater number of years whatever. On this point I cite you to a paper on 

 Fluctuations in Rainfall, read by Alexandec Binnie, Esq., C. E., before the Institution 



