Dr. BiGSBY on the Geography and Geologj/ of Lake Huron. 181 



composed; so that the summit,, with much of the land behind, is a platform of 

 naked rock. Out of these natural terraces, knolls of flowering shrubs and 

 clumps of trees arise. Behind them is the dense gloom of impenetrable woods. 



Of the strait which divides the Grand Manitou from the northern main 

 I possess no information further than what has been stated. At a time when 

 the Manitoulines were quite unexplored, I sailed through the strait without 

 distinguishing it from the numerous passes in that labyrinth of islands. It has 

 now undergone two surveys. 



The strait which divides the Grand from the Fourth Manitou on the north 

 is only one mile broad ; but on the average a league. It has been very seldom 

 visited. 



Of the Fourth Manitou little is known. It is narrow, and of about one 

 third the size of the Little Manitou ; its long diameter crossing the direc- 

 tion of the Manitouline chain. The shores are much indented, and afford 

 a very convenient harbour on its eastern side, which was used in 1821 by His 

 Majesty's schooner Confiance, Lieut. Grant. 



The fifth and easternmost strait between the Fourth Manitou and Cabot's 

 Head is 14 miles broad, and contains many shoals and islands, of which the 

 largest is appropriately named the Isle of Coves, 



The island on which are those singularly shaped rocks called the Flower- 

 pots, has long attracted notice. Accounts differ respecting its precise situ- 

 ation ; but it lies probably about 6 miles S.S.E. of the Fourth Manitou. The 

 Flower-pots are several insulated rocks, the greatest 47 feet high^ consisting 

 of large tabular masses, placed horizontally one upon the other, and broad at 

 the summit, but narrow below. They stand on a floor of rock projecting into 

 the lake from the lofty island which bears their name. 



Cabot's Head, a singular headland, is evidently a continuation of the Mani- 

 touline ridge. It lies 144 miles almost due north of St. Clair. It faces north 

 for about 25 miles, and then passes off to the south and east. It consists of 

 much indented limestone bluffs, rising occasionally to the height of 300 feet, 

 and skirted by numerous reefs and islets. On the western side of the head- 

 land, and to the south of it, the first 64 miles of coast display a range of cal- 

 careous precipices. A little to the north-east of Cape Hurd, the western ex- 

 tremity of Cabot's Head, one of the curvatures of the cliff forms a cul-de-sac, 

 800 yards long and 80 broad, having 7 fathoms water. It thus affords an 

 useful haven in this intricate part of the lake. 



In addition to these remarks on the southern extremity of the Manitouline 

 chain, I have only to notice its generally increased elevation in this part of the 

 main, and in the neighbouring isles. 



