MEDICINAL VIRTUES OF THE FERRUGINOUS WATER OF YURA.
The ferruginous waters are stated by Mr. Rivero, on the authority of Haenk, and of Dr. Vargas of Arequipa, to be tonic, deobstruent, laxative, diuretic, &c.; and, therefore, well calculated to remove general debility, certain forms of hypochondriasis, dyspepsia, and weakness consequent on debauchery.
THE SULPHUROUS WATER.
The jets (los ojos) of this water, as we formerly noticed, are placed above the ferruginous baths, situated in a narrow part formed by the trachyte rock on one hand, and on the opposite side by the gres, or sandy soil, which furnishes the carbonate of soda. An oblique fissure, extending to the base of the trachyte rock, serves as a conduit to this thermal water, which unites itself with that which flows from the bottom of the bath named Tigre. A short way from this jet there are others which flow from other clefts, at almost the same degree of temperature.
It is observed that the source of these waters is at some distance in the interior of the rock, and, according to my notions, they hold communication with the crater, which emits sulphurous vapours, situated a few paces from the water underneath the very house where the sick repose. With respect to the water, having filled a small well situated at the base of the rock where people drink from, the chief object is to have it conducted to the bathing-pits, or basins. The superfluous water not needed for the baths flows out from them by a small channel; and it goes to join the rivulet, which passes within three yards of the bathing apartment.
The sulphurous water flows out in good quantity, making a peculiar noise, and emitting a smell of sulphuretted hydrogen gas, like that of rotten eggs; which is perceptible at the distance of many paces from the place, when the winds are from the east and west. The disengagement of carbonic acid gas occasions the noise alluded to, through the innumerable bubbles which rise on the surface; and at the same time it occasions a shower of aqueous particles, mixed with sulphuretted hydrogen and carbonic acid gas; its colour is whitish, transparent; and on the walls and canals of the baths, it leaves a whitish substance, somewhat dirty, very fine, which when examined proves to be impure sulphur; its taste is at the same time sweetish and acidulated, but it leaves on the palate the taste of rotten eggs.
In the bathing apartment there are four large reservoirs, or basins, constructed with stone and lime; they are equal in size, communicate the one with the other, and are named Tigre, Sepultura, Desague, and Vejeto: in these reservoirs, however, the temperature of the water is not equal: the first indicates on the thermometer of Fahrenheit 90°, the second 89°, the third 88°, and the fourth 87°; the air of the habitation being 70°. In the place where this water was first discovered, it at present indicates as many as 90°: Haenk, in the year in which he instituted his analysis, observed that it was only 86°, which proves that the temperature has since then increased.
The gas which arises from this water, when collected, extinguishes flame; produces in lime-water a precipitate which dissolves in acetic acid with effervescence; and it precipitates the acetate of lead, of a dirty yellow colour. The water reddens blue paper; but, on drying, it recovers its original colour, a circumstance which proves that there is a free acid: turmeric paper it does not change the colour of, unless its volume has been decreased by evaporation. A few drops of any acid produce effervescence. The nitrate of silver gives a violet-colour precipitate, the acetate of lead a dirty yellow, the muriate of barytes a white, but it is necessary to add to it a few drops of acid; the prussiate of potash produces a blue precipitate, using the precaution to reduce the water, and of adding to it some drops of nitric or muriatic acid. Liquid ammonia renders it turbid, which shows that it contains magnesia; corrosive sublimate produces a half obscure precipitate, which afterwards effervesces with an acid; it instantly coagulates milk, renders wine and the water of peaches or pears turbid, giving rise to effervescence with the three last. A piece of clean silver, if placed in it for some minutes, becomes somewhat black; when agitated, it disengages carbonic acid with precipitation, and all the water is filled with bubbles; when boiled, it loses its smell, it disengages all the free acid, and it no longer reddens blue paper.
Four bottles of this water, when evaporated, have given forty-three grains of salts: during the evaporation the surface became coated with a white film, and a light white substance was precipitated, which consisted of the carbonate of magnesia and lime, abandoned by the carbonic acid which had held them in a state of solution.