26" Remarks on the Mineral Springs at the Koogha. 



arc funned of a compact of dark brown clay intermixed with 

 portions of a white and black color, and there is a polished sur- 

 face which tastes acid. The water drawn from this well has a 

 peiceptible chalybeate flavor. It strikes a purple color with 

 infusion of Galls, but is not altered by blue vegetable in- 

 fusion, ammonia, nitrous acid, or lime-water. 



The other spring is found in a ffole about six feet deep, from 

 under the western bank of which the water chiefly r'fscs out of 

 a hole of small circumference, opening into the larger one. 



The walls of this spring are of the same description as the 

 surrounding black clay, are unctuous to the touch, and when a 

 little is applied to the tongue tastes strongly acid. The water 

 is muddy, and when taken from the spring: and allowed to 

 stand deposits a copious dark brown sediment. It soon un- 

 dergoes decomposition when removed from the spring, and 

 then emits a strong smell of sulphuretted hydrogen. The bot- 

 tom of the well is sandy. The water has a strong acid and 

 astringent taste; turns of a deep purple color upon adding in- 

 fusion of galls, and is perceptibly leddened by blue vegetable 

 infusion. Both these changes take place in almost an equal 

 degree after boiling the water. Nitrous acid, ammonia, and 

 lime water, produced no change. I think it is probable, from 

 the black clay being, as correctly as I could ascertain, only 

 about six feet deep, and the bottom of (he well sandy, that the 

 water becomes impregnated with the salts of iron after it springs 

 from the bowels of the earth, by remaining in contact with the 

 clay. 



The temperature of this spring, ascertained by repeated 

 experiments, is 80° F. Perhaps the heat may be occasioned 

 by the decomposition of the pyrites, and the change of the 

 acid from a solid to a fluid state giving out caloric. That the 

 cause of the increase of temperature is very confined in its 

 sphere, seems evident from the contiguous spring being of the 

 natural temperature. 



The production of the sulphate of iron found efflorescent on 

 the surface of the clay, is most probably owing to a large 

 quantity of pyrites in the soil, the sulphur of which receiving 

 oxygen from the atmosphere is converted into sulphuric acid, 

 and unites with the oxide of iron; while perhaps another por- 

 tion of the sulphuric acid combines with the alumine, and a 

 proportion of potash pioduccd by the decomposition of vegeta- 

 ble matter, and composes alum. 



The proprietor of the ground says that the black clay has 

 been gradually increasing in quantity for several years, so 

 that where there was once a hollow there is now an eminence. 

 Can this circumstance serve to assimilate this remarkable na- 

 tural phenomenon in any degree to a mud volcano? 



