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issue out from all kinds of formations, from the granite upwards, 

 in different parts of the world, and become gradually crystal- 

 lized and consolidated in any rock which may be of a loose and 

 porous nature, and not heavily pressed. The deposits of rock-salt 

 and the springs of muriate of soda in the eastern Cordillera, suc- 

 ceed each other from Pinceima on the south to the Llanos de Meta 

 on the north, a distance of about 200 miles in the same linear 

 direction. All the known salt springs in South America are 

 found in bands more or less meridional. 



When the salt does not form beds it is found interwoven in 

 clay, that is, in small veins, like white carbonate of lime veins in 

 a black limestone. The fibres of salt are found perpendicular to 

 the sides of the cracks, like the quartz in veins of fractures. In 

 the splits and horizontal seams the salt is generally divided into 

 thin parallel plates, varied in colour, sinuous, and similar to the 

 general appearance of quartz and other substances in meridional 

 and horizontal veins. 



Salt springs issue from the micaceous schist on the western 

 side of the plains of Mariquita, from the porphyry of the west- 

 ern Cordillera near Supia, and apparently from the fissures in 

 the granite in Autioquia. Near Lima, rock-salt is pierced through 

 by veins of porphyry. The direction of the subterranean salt 

 springs, like that of all mineral solutions, is independent of the 

 inequalities of the surface, and may be traced for miles in me- 

 ridional bands. In England we find the saline springs similarly 

 situated. We may consider Dudley, in Worcestershire, as the 

 northern part, and the mineral waters of Cheltenham as the 

 southern ; all the brine springs are situated in the intermediate 

 space, and almost in a north and south direction. 



Hence we have only to apply the polar force, in connexion 

 with solutions, to account for the formation of salt like all other 

 subterranean products. The natural process is constantly going 

 on under ground without the aid of heat, at least in the sense in 

 which this much-abused chemical phenomenon is employed in 

 geological theories. 



What we have stated above respecting the formation of salts 

 from saline solutions, and the gradual formation of veins and 

 horizontal masses by the hydrostatic power of the solutions, and 

 the force of the crystallizing power of the substances, equally 



