Harbor at about the middle of its western 

 side is Oyster Bay, a tortuous body of water 

 running back some six or seven miles and 

 having a breadth varying from one and 

 a-half miles to half a mile. Both Cold- 

 spring Harbor and Oyster Bay receive at 

 their upper ends fresh- water streams of 

 considerable volume, and at intervals along 

 their coast line, smaller ones. Consequently 

 the density of the water is low, being about 

 1.019 at flood-tide near the surface in the 

 middle of the outer harbor. Coldspring 

 Harbor is a sunken river valley with abrupt 

 fiord-like sides, which extend back into the 

 country for three miles from the upper end 

 of the Harbor. In the valley runs the 

 stream of Coldspring Creek, which expands 

 at three different levels into broad, deep 

 ponds, connected by waterfalls and shaded 

 by dense foliage. The woods which rise 

 from these ponds are densely grown with a 

 rank vegetation and are rich in the fleshy 

 fungi which accompany a moist climate. 



Coldspring Creek, flowing, laden with 

 silt, into the upper end of the Harbor, has 

 formed there, with the aid of the sea, a sand 

 spit which nearly cuts off an inner basin, 

 about 3,000 feet long by 2,000 feet wide, from 

 the outer harbor. The water of the inner 

 basin is decidedly brackish, at high tide 

 varying from 1.006 to 1.016 at the surface 

 and from 1.006 to 1.018 at the bottom. 

 The passage from the inner basin to the 

 Harbor is only 200 to 300 feet wide at low 

 tide, and through this ' gut ' the water flows 

 at times with great rapidity. The mean 

 range of tide is 7.3 feet. The inner basin, 

 which is gradually silting up, exposes about 

 half of its bottom at every low tide for an 

 hour or so. In the outer harbor, above the 



