436 Eighth Annual Report of the 



Adirondack sj'stem of northern New York, the Helderberg hills, 

 the Catskill and Shawangunk Mountains and the Highlands. A 

 broad vallej^ which opens U3ut of the Hudson toward the southwest 

 through Orange county, separating the Shawangunk ridge from 

 the Highlands, is here included as part of the Hudson valley. 



The prevailing winds of the Hudson valley blow nearly north 

 and south throughout the year; southerly winds predomanating 

 in thel vicinity of Albany from May to October, inclusive, and 

 northerly winds during the remainder of the year. Toward the 

 southern limit of the valley the periodicity of the winds appears 

 to follow that of the Atlantic, changing from south to north in 

 September. No long records of the wind direction in the Cham- 

 plaini valley were procurable in a form suitable for icomparison; 

 but a five years' series observed prior to 1850 indicates substan- 

 tially the same conditions as at Albany. 



The high temperature of the sheltered seetion of the lower Hud- 

 son! valley is represented by the normals of Ardenia, while Honey- 

 mead Brook and Mountainville, although located within the val- 

 ley slopes, are exposed much imore to the conditions of the high- 

 lands. The annual ranges at the three stations vary but little 

 from 46 degrees, which is below the average of the interior of the 

 State, probably owing to the tempering influence of the ocean, 

 although the advance of the spring and autumn seasons appears 

 to be but little retarded bv maritime influences. Proceeding 

 northward to the comparatively open country istretching from the 

 vicinity oif Albany toward Lake Champliain, it is found that the 

 summer temperatures are not reduced, while the winters are con- 

 siderably colder. This increase of the annual range of tempera- 

 ture indicates that in summer sontherly winds carr}^ the warmth 

 of the lower valley well to the northward and possibly even over 

 the region of Lake Champlain, wihile a reverse direction of the 

 winds of winter practically extends the limits of the Champlain 

 valley climate below Albany, pro-bably to the ridge of the Cats- 



