Analysis of (he Pittsburgh Mineral Spring. 133 



I cannot exemplify this better, than by referring to the waters 

 of Ballston and Saratoga, all of which contain iron in 

 greater or less quantity, but containing also, as most of them 

 do, a considerable quantity of a neutral salt, the effects of 

 the iron as a tonic are counteracted, by the purgative quality 

 of this salt, which totally alters their medicinal qualities, and 

 renders the use of them inexpedient in many diseases, where 

 a purely chalybeate water would have the most beneficial 

 effects. 



In taking the Pittsburgh water as an example of a nume- 

 rous class of natural springs, properly called chalybeate, I 

 shall first make some observations on the effect of iron on 

 the system, and then shew that in the state in which it is 

 found in such waters, it is particularly calculated for the cure 

 of such diseases as preparations of iron are found bene- 

 ficial in. 



The effects of iron on the system are sufficiently nume- 

 rous in the animal economy ; it stimulates the fibres of the 

 stomach and abdominal viscera ; it augments the tone of 

 all the muscular fibres ; strengthens the nerves and gives the 

 whole weakened system remarkable energy ; it increases the 

 strength of the pulse, and from its use, the pale emaciated 

 countenance assumes a healthy florid color. 



With regard to the various preparations of iron, those 

 which seem best calculated for the purpose, are such as are 

 most certainly conveyed into the blood, and most easily con- 

 verted into oxide. Of these, iron dissolved by carbonic acid 

 and held in solution in a mineral water, seems by far prefera- 

 ble, and with respect to quantity, experience has shewn us 

 that small doses of iron produce better effects than large 

 ones, particularly when persevered in, as should always be 

 the case for a considerable length of time. This observation 

 is particularly made by the celebrated Doctor Cullen, and 

 should always be attended to. Mineral waters, he remarks, 

 often produce cures which we in vain attempt to perform by 

 the combinations of iron in our shops, even although those 

 waters contain nothing but iron ; this is manifestly owing to 

 the weakness of the dose, in proof of which we find that the 

 strongly impregnated waters seldom answer so well as those 

 which we commonly reject. 



The Chalybeate water at Pittsburgh I can venture to re- 

 commend for all purposes for which Chalybeates in general 

 are given, and though the quantity of iron is small, yet it is 

 equal to that contained in some of the most celebrated Ger- 



