‹‹‹ Vitr. 8.3.18 | Table of Contents | Vitr. 8.3.20 ›››
19In the same way brass which is more solid by nature, if treated in the same way, will dissolve, and become verdigrease; and even pearls and flint-stones, which neither iron nor fire can destroy, when submitted to its action, are dissolved and dissipated by an acid. With these facts before our eyes, we may fairly argue, that calculous disorders may be cured by acids, on account of their acridity.
19On the same principle, copper, which is naturally more solid, will disperse and turn into verdigris if similarly treated. So, also, a pearl. Even rocks of lava, which neither iron nor fire alone can dissolve, split into pieces and dissolve when heated with fire and then sprinkled with vinegar. Hence, since we see these things taking place before our very eyes, we can infer that on the same principle even patients with the stone may, in the nature of things, be cured in like manner by means of acid waters, on account of the sharpness of the potion.