MINERAL "WATERS OF DU19BLANE. 477 



X)n the general question, the remark by Dr Saunders is per- 

 fectly just, that, *' considering the comparative accuracy to 

 which chemists are at present able to carry their inquiries, we 

 can hardly suppose, that whatever slight error might occur in 

 the estimation of minute quantities, the actual existence of any 

 powerful agent on the human body, in any mineral water, 

 should escape the nicety of research." Yet though this is just, 

 and though we can have no hesitation in rejecting the opinion 

 which would ascribe the medicinal qualities of mineral waters 

 to unknown or mysterious causes, or which would deny all 

 power to those in which an active chemical composition can* 

 not be discovered, difficulties on this subject undoubtedly ex- 

 ist, and there is some room for that scepticism which has been 

 extended to this department of the Materia Medica. 



Of this no better example can be given, than the celebrated 

 Bath water. It has always been found difficult to account for 

 its powers, the ingredients which are obtained in its analysis 

 being substances of little activity, and the principal ones, in- 

 deed, being apparently inert. It contains in an English pint, 

 along with a slight impregnation of carbonic acid, about 9 

 grains of sulphate of lime, 3 grains of muriate of soda, 3 grains 

 of sulphate of soda, r|ths of a grain of carbonate of lime, yth 

 grain of silica, and y'^th grain of oxide of iron. Now, from 

 these ingredients unquestionably no medicinal power of any 

 importance could be expected. They are either substances al- 

 together inert, or are in quantities so minute, as, in the dose in 

 which the water is taken, to be incapable of producing any 

 sensible effect. Some have from this circumstance been dis- 

 posed to deny altogether any virtues to these waters ; but the 

 reverse of this appears to be established by sufficient evidence, 

 and what is still less equivocal, the injurious effects they some- 

 times produce, and the precautions hence necessary in their 

 use, sufficiently demonstrate their active powers. To account 



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