344 



APPENDIX. 



VI. 



Analysis of the Mineral Water, of tempera- 

 ture taken from the hot springs at the 

 Inca's Bridge y in the Cordillera of the Andes, 



Royal Institution, 

 June 2d, 1828. 



Sir, 



I have at last been able to find time to com- 

 plete an examination of the water from the Inca's bridge 

 which you gave into my hands ; and though I have no 

 doubt, from the nature of the water, that it had under- 

 gone changes since you removed it from its source, (as 

 was indeed sufficiently evident from the deposition in 

 it of black hydrosulphuret of iron,) it still was very 

 curious in its natural characters. 



The water is distinguished, in the first place, by a large 

 quantity of sulphureted hydrogen, which it holds in 

 solution ; this renders it fetid, and very nauseous to the 

 taste. It has at one time also been distinguished as a 

 chalybeate, holding iron in solution, but at present al 

 the iron is separated in the form above described. 



