NEW YORK STATE MUSEtTM 



TOPOGRAPHY AND DRAINAGE 



The Black river valley may be looked upon as the principal 

 topographic feature along the western border of the Adiron- 

 dacks, and the Port Leyden quadrangle represents a consider- 

 able portion of this valley where it is deepest. Black river 

 enters the quadrangle at the southeast corner at an elevation of 

 looo feet and, after following a northwest-north course, leaves it 

 near the middle of the northern boundary at an elevation of about 

 740 feet. From the river eastward there is a general upward 

 slope toward the Adirondacks. Facing the river there is a steep 

 slope, which within 2^ miles, passing eastward, gives way to 

 a generally level sand-flat area lying at an elevation of from 

 1200 to 1300. Along the eastern edge of the map several points 

 reach altitudes of from 1300 to 1340 feet. 



Passing westward from the river the general rise is much 

 more rapid. Two terraces are here well developed from the 

 latitude of Port Leyden northward. The lowermost terrace 

 is from 2^ to 4 miles wide and has a steep front rising 

 from 300 to 400 feet just west of the river. The upper ter- 

 race is known as Tug hill whose very steep eastern front 

 rises from 400 to 450 feet and makes up the western por- 

 tion of the quadrangle. The highest point on this side of 

 the river is Gomery hill, near the western edge of the map, 

 which shows an elevation of nearly 2100 feet, while altitudes of 

 1800 to 1900 feet are common. This high ground to the west 

 of the river is a part of the broad high land area which lies 

 between Black river and Lake Ontario. It is interesting to note 

 that the elevations of the western portion of the quadrangle are 

 much greater than those of the eastern or Adirondack portion. 

 In order to reach elevations of 2100 feet or over it is necessary 

 to pass 20 or 25 miles east of Black river into the Adirondacks 

 to the high points around the Fulton chain of lakes. 



Within the map limits Black river descends 200 feet, through 

 a series of still waters and rapids, before reaching Lyons Falls. 

 At Lyons Falls there is a sudden drop of 60 feet, but from this 

 point northward to the map limit the river flows by a winding 

 course through an old lake bottom [see p. 54] and the gradient 

 is almost imperceptible. The largest tributaries to Black river 

 from the east are Fall brook. Moose river, Fish creek, Otter creek 

 and Independence river. By far the largest of these is Moose 



