ANCIENT WATER LEVELS OF CHAM TLA IN— HUDSON VALLEYS 227 



spond. It is to be anticipated, however, that the kettle phenomena 

 should be very irregularly spaced from north and south and more 

 likely to be found in areas of frontal or strong marginal ice 

 drainage than elsewhere. 



Furthermore there may be more than one line of pitted plains 

 and terraces at varying distances and elevations from the main 

 drainage channel as has been explained in the preliminary account 

 of glacial drainage. 



The plotting of the known kettles gives an example in the 

 moraine at Brooklyn at about 100 feet ; some at the foot of Crow's 

 Nest Mountain at 160 feet; and other shallow pits south of 

 Poughkeepsie near Mine Point at about 170 feet, all of which fall 

 fairly closely into a southward tilted plane, and all three lying 

 above the water levels in that part of the Hudson river valley. 



North of the above described kettles on the Rhinebeck sheet 

 and the southern part of the Catskill sheet are small groups of high 

 lying kettle deposits, probably marking earlier marginal deposits 

 than those nearer the river when the Hudson river glacier had 

 shrunk to smaller dimensions. The lowest of these depressions 

 inclosed by the 240 foot contour near Elizaville overlooks a flat of 

 water-laid deposits at about the upper limit of signs of standing 

 water after the disappearance of the ice from this part of the 

 valley. 



On the whole the kettle holes on the Rhinebeck and the southern 

 third of the Catskill sheet are above the general level, and those 

 on the north and south are much above the levels marked by ter- 

 races or deltas indicating open, standing water. 



Very few kettles obtrude themselves on our notice in going 

 north to the southern part of the Troy and Albany sheets. Ex- 

 cepting one low kettle on the Troy sheet near Teller hill at 240 

 feet, the kettles from near Albany southward to the middle of the 

 Catskill sheet fall along a tilted line which is about one half that 

 of the tilt of the upper marine limit in the Champlain district. 

 The actual tilt is at the rate of 2.8 feet a mile for about 50 miles. 



Here again comes a decided break in the kame kettle deposits. 

 From the northern middle portion of the Troy sheet to the 

 northern part of the Schuylerville, there are none of these signs 

 of deposition in the presence of ice near the Hudson river at levels 



