ROCKY MOUNTAINS. 241 



ag-ency, that mountains of amygdaloid and basalt have been 

 thrown up ; and the same substance is spread over the neighbor- 

 ing plains, to what depth is not known ; but from observations 

 made upon channels of rivers and the precipices of ravines, it is 

 evidently very deep. The tops of some mountains are spread out 

 into horizontal plains, some are rounded like domes, and others 

 terminate in conical peaks and abrupt eminences of various mag- 

 nitudes, which are numerous, presenting themselves in forms 

 resembling pillars, pyramids, and castles. There are several 

 regularly formed craters ; but these, presenting themselves in 

 depressions or in cones, are rendered obscure by the lapse of 

 time." Mr. Parker also states that nearly all the rocks of this 

 region are amygdaloid, i. e. a trap rock in which agates and mine- 

 ral substances are scattered about like almonds in a cake; basalt, 

 lava, and volcanic glass, or obsidian. The Rocky Mountain chain 

 extends north to the Arctic ocean, skirts along its coast, and is 

 probably connected subterraneously, with the volcanic band which 

 we shall presently describe, extending from the Aleutian Isles, or 

 extremity of the peninsula of Alaska, in Russian America, to the 

 Molucca Isles. The whole shore of western America, from the 

 peninsula just mentioned to Vancouver's Islands, presents a bold 

 and awful aspect, being bordered with mountainous steeps, cov- 

 ered with primeval forests, and containing two of the most 

 elevated peaks in the northern part of America, Mount St. Elias, 

 18,000 feet, and Mount Fairweather, 14,913 feet above the ocean. 

 Passing from the peninsula of Alaska, we find the volcanic chain 

 extending through the Aleutian or Fox Islands, which are a long 

 and numerous group extending nearly to Kamschatka. From al- 

 most every island, steep and lofty peaks arise, and from many, 

 volcanic fire is discharged. In 1795 an island was thrown up and 

 added to this group, by an eruption from beneath the sea, and con- 

 tinued 1o increase, till in 1807 it measured twenty miles in circuit. 

 Throughout this whole tract, earthquakes of the most terrific de- 

 scription occur. The line of volcanic craters continues through 

 the southern extremity of Kamschatka, where are seven active 

 volcanoes, which in some eruptions have scattered ashes to im- 

 mense distances. The chain is prolonged through the Kurile 



