THE GEOLOGIST 



MAY, 1860. 



ON CANADIAN CAVERNS. 



By George D. Gibb, M.D., M.A., F.G.S., Member of the Canadian 



Institute. 



(Continued from page 133). 



1. — Cayeens on the Shoees of the Magdalen Islands. 



On passing the interesting group of islands in the Gulf of St. 

 Lawrence, known as the Magdalens, the observer is struck with their 

 beautifal and picturesque appearance, which is suddenly presented 

 to his view. The cliffs, which vary in height, present equally 

 various colours, in which the shades of red predominate ; these, con- 

 trasted with the yellow of the sand-bars, and the green pastures of 

 the hill-sides, the darker green of the spruce trees, and the blue of sea 

 and sky, produce an effect, as Captain Bayfield describes, extremely 

 beautiful, and one which distinguishes these islands from anything 

 else in the Gulf. Such an agreeable picture it has been my own 

 good fortune to witness and admire. The striking feature in their 

 formation is the dome-shaped hills rising in the centre of the group, 

 and attaining a height of from two hundred to five hundred and 

 eighty feet. They are composed of the Triassic or New Hed Sand- 

 stone formation, which forms their base, being surmounted or topped 

 by masses of trap rocks. The highest of the Magdalens is Entry 

 Island, with an elevation of five hundred and eighty feet ; its red 

 cliffs rise at its north-east point to three hundred and fifty feet, and 

 are what they have been described, truly magnificent and beautiful. 

 The soft and friable character of the brick-red cliffs forming the 

 shores of these islands, with their remarkable capes and headlands, 

 have in many places yielded to the force of the waves, and have be- 

 come worn into arches and caverns. This is more strikingly mani- 

 fest at Bryon Island, which is nearly surrounded by perpendicular or 

 overhanging cliffs, which are broken into holes and caverns, and fast 

 VOL. in. X 



