M O U 



Ingleborough, mountain limestone, gritstone, c. . . 2,361 



Madrid 2,276 



Pennigent do. .... 2,270 



Whernside (Kettlewell) do. .... 2,263 



Fountains Fell do. .... 2,180 



Snea Fell (Isle of Man) clay slate 2,004 



Pendle Hill, mountain limestone, millstone, grit. . . . 1,803 



Rye Loaf Hill do If.SS 



Malvern Hills, Syenitic granite 1,441 



^Cataract of Tequendama (S. America) 600 



St Peter's, summit of the Cross 535 



Pyramids (Egypt) 4"j 500 



Natural Bridge of Iconozo (S. America) .... 300 



Caspian sea below the ocean T***^ 306 



Gay Lussac highest altitude ever attained by a balloon, 



Sept. 16, 1804 22,900 



Highest flight of the Condor 21,000 



Height attained by Humboldt up the Andes, June 23, 1802 19,400 



Highest limit of lichen plants . 18,225 



Lower limit of perpetual snow on the Equator . . . '15,720 



Farm House of Antisana 13,435 



Highest limit of trees 11,125 



Superior limit of oaks in the torrid zone .... 10,500 

 Convent on Mont St Bernard (Switzerland) . . . 8,040 



Do. of St Gothard (Alps) . 6,810 



MOUNTAINS, visibility of. See Refraction. 

 MOUNTAINS, attraction of. 



Dr Maskelyne was the first who satisfactorily proved the attraction of 

 mountains by their effect in drawing the plumb line from its vertical 

 direction. The mountain selected was Schehallien in Scotland, the mean 

 height of which above the surrounding valley is 2000 feet, and above the 

 level of the sea 3550. The attraction of this mountain was found = 5",8 : 

 from which Dr Hutton calculated the mean density of the earth to be 

 near 5 times that of water, or as 99 to 20, and almost double the density 

 of rocks near the earth's surface, Mr Cavendish, upon totally different 

 191 



