16 N. H. Winchell on the Glacial features of Green Bay. 
frequently uniting with the shore-line, the entrances to the little 
bays being uniformly very deep. ‘The passage through Port 
des Morts is 21 fathoms, north of Louse island 24 fathoms. 
The mouth of Eagle harbor is 11 fathoms, of Ellison’s bay 12 
fathoms, and of Hedgehog harbor 17 fathoms. The average 
depth of Green Bay is 16 to 18 fathoms. 3 
The uniformity in the direction of these bays is another 
remarkable fact. They indent the peninsula in a southerly or 
southeasterly direction. On the contrary the bays on the op- 
posite side of the peninsula, and opening into Lake Michigan, 
have a very uniform direction northerly or northwesterly, com- 
plementing those opening into Green Bay in such a way, that 
the peninsula is in several cases almost intersected by their near 
inosculation. 
The barrier of the Niagara limestone is broken through at 
each of these bays, and its broken off ends form perpendicular 
and bald bluffs which face each other across their entrances, 
and rise to the height of 75 to 175 feet. Government and Hib- 
bard’s bluffs enclose Sturgeon bay. The former has a height of 
115 feet, the latter about 80 feet. Eagle Bluff is on the south 
side of Kagle harbor and has a height of 149 feet 10 inches. 
Its counterpart on the north side is about 60 feet. Garden Bay 
in Great bay de Noc is another example of the same pheno- 
menon. The Niagara barrier is more broken down between 
Port des Morts and Pt. de Morts and Pt. de Tour than at any 
other place. Projecting southward, the peninsula which en- 
closes Great bay de Noc and terminates with Pt. de Tour, is a 
counterpart of that which encloses Green Bay ; and the whole 
interval between Door Bluff on the south and Sag Bluff in Great 
bay de Noe on the north, is but an enlarged illustration of the 
phenomena already described. In this case the Niagara lime- 
stone is so completely broken down as to admit the waters of 
Lake Michigan, the Potawatamie islands, which lie in that 
a being its only parts remaining above the level of the 
lake. : 
