CARARACTS AND INUNDATIONS. 185 



of all mineral waters. Modern chemistry has thrown great light 

 on this class of waters ; they were formerly supposed to he all im- 

 pregnated with sulphat of iron. IMonnet has ascertained that most 

 of them do not contain this salt, and he supposed that the iron is 

 dissolved without Uie intermedium of an acid. It is at present 

 known, that the iron is not in the state of sulphat, but is dissolved 

 by means of the carbonic acid, and forms the salt which we have 

 called carbonat of iron. Lane, Rouelle, Bergman, and many 

 other chemists, have put this out of doubt. The greater or less 

 quantity of carbonic acid, and the state of the iron in waters of this 

 kind, render it necessary to distinguish the present class into three 

 orders. 



The first order comprehends martial acidulous waters, in which 

 the iron is held in solution by the carbonic acid, whose superabund- 

 ance renders them brisk and Mibacid. The waters of Bussang, 

 Spa, Pynuont, Pouhoii, and La Dominique de Vals, are of this fir*t 

 order. 



The second contains simple martial waters in which the iron is 

 dissolved by the carbonic acid, without excess of the latter. These 

 waters consequently arc nut acidulous. The water of Forges, Au- 

 niale, and Condi-, as well a* the greater mimher of ferruginous 

 Haters, are of this order; this distinction of ferruginous waters 

 uas made by Duchanoy. 



But we add a third order, after Monnet, which is that of waters 

 containing sulphat of iron. Though these are extremely rare, yet 

 some of them are found. Mouoet has placed the waters of Passy 

 in this order. Opoix admits tile sulphate of iron, even in a con- 

 siderable juanlity, hi the waters of Provins. It is true, that De 

 Fourcv denies its existence, and considers the iron of tuese waters 



p 



as dissolved by carbonic acid. But no decision can be made re- 

 specting this subject, because the results of these chemists entirely 

 disagree* and require new experiments to be made. It nm.st bo 

 added, that the iton is not found alone in these waters, but is mixed 

 with chalk, sulphat of lime, various muriatic salts, &(:. However, 

 fl.s the inetul they contain is the principal basis of their properties* 

 they must be called ferruginous, in conformity with the principles 

 we have laid down. 



As to the saponaceous waters admitted by Dnchanoy, we mnt 

 wait till chemitul mid medical experiments have ascertained tim 



