REPORT ON MINERAL AND THERMAL WATERS. 47 



cause goitre, has no such tendency at a lower one, so soon, that 

 is, as its waters have become duly aerated in the progress of 

 their descent. 



In like manner, water which rises from calcareous rocks, or 

 which has become stagnant in lakes, has a tendency to produce 

 goitre, not by reason of its solid contents, but owing to the 

 absence of the usual quantity of air. 



Boussingault also relates the extraordinary fact, that those 

 provinces, which are provided with salt containing iodine, are not 

 aflfected with goitre, whilst in others, where the salt is destitute 

 of that principle, the disease is endemic. 



There has likewise been an attempt lately made by a German intheiieiec- 

 physician* to mark a difference in the electrical condition of t'^''^^' condi- 

 one of those springs, which, though almost chemically pure, 

 seemed nevertheless to possess active properties. 



He states, that the water of Gastein conducts electricity better 

 than common water would do. Such a statement, however, 

 cannot receive any credence, until all the details of the method, 

 by which a result so paradoxical was arrived at, have been sub- 

 mitted to the judgement of scientific men. 



Kastner had previously endeavoured to establish the same in 

 the case of the waters of Wiesbaden, but the fallacy of his ex- 

 periments is now generally admitted. 



Equally fanciful appear the opinions of those, who attribute in their 

 to natural thermal springs a greater capacity for heat than be- capacity for 

 longs to artificially prepared waters of equal temperature, and '^^'" 

 who maintain that they cool more slowly in consequence. 



M. Longchamp, in France, by experiments on the waters of 

 Bourbon ; Professor Gmelin, of Heidelberg, by similar ones on 

 those of Baden- baden; Reuss, Neumann, and Steinmann bysome 

 on the springs of Carlsbad; andSchweigger andFicinus by others 

 on those of Toeplitz, have exposed the fallacy of this notion; and 

 have shown, that in reality no difference exists in this respect 

 between the one and the otherf. 



Let us next proceed to consider the improvements, that have Analysis of 

 been lately introduced into our methods of analysing the solid """*^f^' 

 and gaseous constituents of mineral waters. 



Most chemists are by this time familiar with the simplification General 

 upon the plan of proceeding, which we owe to Dr. Murray;}; of pi^'icipies. 

 Edinburgh, in consequence of his having pointed out, that as the 

 salts existing in a spring need not be the same with those we ob- 

 tain on evaporation, and as salts viewed as incompatible may 



• Dr. Pettenhofer. + Consult BischofF, Vulk, Mineralq., p. 364. 



X Transactions of the Royal Society of Edinburgh. 



