5wr la Theorie des Volcans. S3 



discovering that on Chimborazo the magnetic power ceased 

 at 20,700 ft. corresponding with 10,500 ft. of Mont Blanc, 

 and the level of the sea at 83° N. lat. (p. 14.) Captain Ross 

 has recently determined the magnetic pole to be more south- 

 ward, in lat. 71° — 72°. But this by no means throws over 

 all the count's arguments. Our author proceeds (p. 15.) to 

 treat on the fluids by whose separation matter was originally 

 developed: — 1. The ethereal universal fluid ; 2. Caloric. 

 3. Light ; and, 4, 5, their auxiliaries, the electric and the 

 magnetic fluids ; lastly, that fluid which is combined of all, 

 X)olca7iic Jire, Under these impressions he investigated the 

 course of natural phenomena, and the results will be laid 

 before the public in the forthcoming work. Some of them 

 we state here. The parallelism of volcanoes is the first: 

 they never appear isolated. The fluids above-mentioned 

 depend on the sun; and their influences cease at 80° N. and 

 65° S. The points of intersection of the equator and the 

 ecliptic are correspondent with similar points of intersection 

 between the equator and the course of the volcanic fire, the 

 latter of which are visible ; the line of junction of these points 

 making an angle of 5° with the earth's radius, and this angle 

 being the constant measure of the divergence of all the vol- 

 canic radii, horizontal or vertical. (There is some difficulty 

 in understanding the count's meaning in this place, arising 

 from a want of perspicuity.) But he states that the slopes 

 of the summits of volcanoes, opened by the flow of lava, are 

 all towards the equator, with a trifling inclination to the west, 

 (p. 17.) He next assigns to the Gulf of Mexico, as M. de 

 Humboldt has done before, the central seat of volcanic fire, 

 taking the correspondent inverse focus to be in the Archi- 

 pelago of the Molucca Islands. Forming a circle on the 

 volcanic equator round these islands as a centre, and dividing 

 it into segments of 10°, he found that radii drawn through 

 these points passed through the lines of direction, and to 

 the limit of all the volcanoes in the globe. 1st, to 90°, passes 

 by the Philippine Islands, Manilla, and China. 2d, to 80°, 

 follows a nearly similar course. 3d, to 70°, commences at 

 the Isle of Niphon and finishes at Japan. 4th, to 60°, forms 

 the chain which passes through the Kurile Islands and ex- 

 tends to Kamtschatka about 70° N. lat., which with Iceland 

 and Jan Mayen's Island (about 70°) seems to limit the vol- 

 canic action to that latitude. 5th, to 50°, passes by Ma- 

 gellan's Island to Behring's Strait. 7th, to 30°, forms the 

 volcanoes of the Marian Islands. 8th, to 20°, forms the vol- 

 canoes of the Caroline Islands. 9th, to 10° extends to the 

 Sandwich Islands, (p. 19.) 



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