connected with Health and the Arts. 313 



careous salts sufficient to curdle soap in water, nor to har- 

 den the vegetables which are boiled in it. In this latter alter- 

 native, it is hard, and is usually regarded as unwholesome 

 and indigestible. 



It must not, however, be supposed that water, the more it 

 is chemically pure, that is to say, freed from all foreign ad- 

 mixture, is therefore proportionably salubrious and agreeable to 

 the taste. This is far from being the case. Distilled water, 

 which contains neither salts nor gas, is both insipid and dis- 

 agreeable, and feels heavy upon the stomach. In water, there- 

 fore, there are certain foreign bodies which are beneficial, and 

 which improve its virtues as a refreshing beverage ; and there 

 are others, on the contrary, which are hurtful ; and hence the 

 importance of our being able to discriminate between the two 

 classes. To the former class belong atmospheric air, carbonic 

 acid, the chloride of sodium, and, according to M. Dupasquier, 

 a small proportion of the carbonate of lime ; to the latter, the 

 sulphate of lime, and the nitrate, also the chloride of calcium, 

 so soon as it is in considerable quantity, and all organic mat- 

 ter, especially when in a state of decomposition. 



It is scarcely necessary to insist upon the utility of air, 

 or at least of oxygen, in water, and of carbonic acid : the 

 change which boiling or distillation produces in the agreeable 

 and wholesome qualities of this fluid is known to every one. 

 Not so, however, with regard to the presence of carbonate of 

 lime, which has hitherto been supposed to be hurtful ; this opi- 

 nion the author conceives is a popular error, and on this point 

 his views are new. Here it is scarcely necessary to remark, 

 that the author excludes from this favourable judgment all those 

 waters which, like those of Saint At tyre near Clermont, contain 

 as much as 15 grains of the carbonate of lime and magnesia 

 in 1.76 imperial pints ( deux grammes par litre). The propor- 

 tion in which he esteems them useful is from 3 to 4 grains 

 (de 0,20 a 0,25 grammes), in the same quantity of water. He 

 reposes this conclusion upon the well-known properties of the 

 bicarbonatis, the alone state in which the great insolubility 

 of the carbonate of lime will allow him to view it in any 

 water which promotes digestion ; and he believes that the 



