But altho’, from what has been said, it appears not only that lime-water, but also a solution of soap, dissolves the stone in close vessels as fast, nay faster, than the _thermæ Carolinæ_; yet these last waters, when the _calculi_ were so placed in open vessels, that the water from the fountain might constantly flow along them, effected a much quicker dissolution than lime-water, or even soap-lye, or indeed any known menstruum, except, perhaps, strong spirit of nitre: for, in the first experiment made by Dr. Springsfeld, a _calculus_ of two ounces and a half was, in this manner, quite dissolved in six days. From this experiment, compared with that of Dr. Springsfeld mentioned above (B), it will be found, upon calculation, that the dissolving power of the Carlsbad water, when it is allowed to flow constantly from the fountain along the stone, is nearly 39 times greater than when it is only poured fresh on the _calculus_ once a day[202]. What may have been the reason of this surprising difference of the lithontriptic power of the Carlsbad water in these different circumstances, I will not pretend to say. I think it can scarcely be accounted for from the gentle motion of the water along the surface of the _calculus_. Was it then owing to some very volatile active part, which the water quickly loses, after being taken from the fountain? But how great soever the dissolving power of the Carlsbad waters may be, when they issue from the bowels of the earth, yet that they do not communicate a much greater dissolving power to the urine, than lime-water, will appear from comparing the two following experiments.