384 On a Mineral Water. 



Or, as they exist in the mineral salt, in 100 parts : 



Grains. 

 Extraneous substances . . . . ,3.2 



Sulphate of alumine . . . . . 38.0 



Sulphate of iron , . . . . .2.4 



Free sulphuric acid . . . , , 4.6 



Water 51.8 



100.0 



Description and Analysis of a Mineral Water existing in the 

 Andes, with a Test for Iodine, 



Since the discovery of iodine and the researches of Sir H. 

 Davy and Gay Lussac, this substance has been found in se- 

 veral mineral waters and marine plants, and the waters which 

 have contained it have often been distant from the sea, but not 

 out of the sphere of supposed communication. Daring my 

 residence in this country, I have discovered iodine in many of 

 the saline springs in the Andes, at very different altitudes, and 

 which did not give the usual indications of an hydriodic salt 

 with the test of sulphuric acid and starch. M. Balard*, in ex- 

 amining the waters and products of the Mediterranean, and 

 Dr. Cantee also, when operating upon those of Castelnuevo 

 d'Astif , discovered the same circumstance ; it became neces- 

 sary, therefore, to search for other re-agents more applicable. 

 The nitrate or acetate of silver I found a very delicate test for 

 iodine in most of its combinations and to answer the necessary 

 indications J. The salt spring now under consideration is si- 

 tuated in the hacienda, or farm of Seiior Rafael Arboleda, fif- 

 teen leagues from the city of Popayan, in the Andes, at a 

 height of ten thousand feet above the level of the sea, and at 

 a distance, in a straight line, of at least eighty or ninety miles 

 from that element §. The situation of this spring approaches 



* Annales de Chimie, tome xxvlii. p. 179. t Ibid, tome xxviii. p. 221. 



\ Dissolve one grain of hydriodide of potassium and three grains of common salt 

 in 3000 grains of water, and add a solution of nitrate of silver, the liquid will imme- 

 diately become milky ; it must then be heated, when the chloride and iodide of silv'Sr 

 formed, will separate from the water. Collect this precipitate and digest it in am- 

 monia, when the chloride of silver will be dissolved, and the iodide of silver will re- 

 main. The delicacy of this test is so great, that in a small portion only of this mix- 

 ture it was perceptible, whilst the ten ourrces of the mineral water, when evaporated 

 to dryness, gave liuta very slight pink tinge with starch. 



§ It is very near and at the same altitude wherQ the bafk called PitayO) so celC" 

 brated for its febrifuge properties, is found. 



