10

thermal vapours. In and near the town (Lichtenthal) chalybeate springs originate, and are effectually employed after a course of Baden. They contain 2 grains of solid ingredients in 16 ouncesviz., 11⁄2 of carbonate of iron, of carbonate of soda, of carbonate of lime, of chloride of magnesium, but no carbonic acid; hence you may beware of confounding them with chalybeates containing less iron, but accompanied by the indispensable volatile gas. Though the chief employment of Baden be external, the water is also frequently ordered internally-pure or with whey. To render it more efficacious in torpid venous obstruction of the abdominal vessels, an imitation of Karlsbad water is artificially prepared, by adding, according to Kölreuter's prescription, sulphate and carbonate of soda, so that about 50 grains of solid constituents impregnate a pint of the water. The physicians seem all greatly occupied during the season (Drs. Rüff, Müller, Gaus, Schrauder, Wilhelmi, Berton, Füsslin, Brumm, Schmidt, Brandis, Jörger, Berg, Heiligenthal), though a very numerous portion of the visitors seek only recreation amid the charms of the surrounding scenery.

LECTURE XVIII.

OEYNHAUSEN-NAUHEIM.

TO-DAY I shall bring to your notice the two most recently discovered German spas, viz. Oeynhausen and Nauheim.

*

Oeyhausen (long. east 9°-lat. north 52°), the youngest member of the family of spas, may be reached from Cologne in eight, and from London in about twenty-four hours. It is within sight of the Rehme Station, near the junction of the Werre and the Weser. It owes its origin to the salt-works, to which it is contiguous (Neusalzwerk); and though the last discovered (since 1845), it already enjoys a high reputation in the cure of diseases in which the saline springs are indicated.

It is situated between Minden and Herford, at an equal distance of ten miles. To obtain a fresh supply of salt, a hole was bored (now 2,220 feet deep), when, unexpectedly, a warm salt-spring flowed out in great abundance, giving rise to the spa under consideration.

The borehole and its adjoining baths are situated to the southwest of the salt-works, in a fertile valley, extending beyond the Werre and joining the valley of the Weser. It is bounded on the north by the Weser Mountains (900 feet high) which can be seen for several miles, and which the River Weser intersects in the Porta Westphalica, near Hausberg (five miles from Neusalzwerk).

The steep Margaret and Jacob Mountains (constituting the Porta Westphalica) are invested with a pleasant appearance by groves of beech, and the tower built upon the former mountain affords a charming panorama of the environs. The Demberg and Kappenberg constitute, respectively, the southern and eastern frontiers. Behind these rise the Steinegge, Ebenöde, &c., enclosing Vlotho in a deep valley. From the highest point (the Bonstapel), the town of Minden can be discerned in a due northerly direction through the Porta Westphalica. The spa is thus protected by the surrounding mountains from violent extremes of temperature, without being exposed to the foggy exhalations of

*The last station before Minden.

the Werre and Weser, these rivers lying below its level. A mild and healthy climate prevails, though sometimes subject to sudden changes. The mean temperature of the soil is 50° Fahrenheit. The mountain-masses of the environs belong to that class formed of horizontal layers. The lowest stratum is composed of shelllime. Above this appear the white and red sandstones, then variegated layers of marl (mostly red); a peculiar layer of white calcareous marl then follows, frequently employed for manuring the fields, and containing numerous crystals of sulphur-pyrites. Towards Neusalzwerk it is covered by black slate and pebblestones, which former may be considered as the transition into the lyas-formation that occupies the south. We moreover find tertiary marl in the Demberg, with remains of testaceous animals, and a considerable stratum of tufaceous lime between Valdorf and Vlotho. The borehole lies 217 feet higher than Amsterdam, and thus extends to 1,994 feet below the level of the sea-probably the greatest depth ever reached. The salt-water was first perceived at a depth of 574 feet, containing 15 per cent. of salt, and supplying of a cubic foot of water per minute; thence the quantity of water, the temperature (about one degree Reaumur for 120 feet of depth), and proportion of salt gradually increased. At 600 feet the temperature was 124° R.; at 1,004 feet, 15° R.; at 1,100 feet, 18° R.; at 1,586 feet, 194° R.; at 1,595 feet, 20° R.; at 1,951 feet, 25° R.; and at 2,219 feet, 263° R.=92° Fahrenheit. From 13 per cent. the proportion of salt increased to 4, and the flow of water from two-thirds of a cubic foot gradually augmented to fifty-four cubic feet per minute.

The upper part of the hole is now enlarged to a width of nine inches (as far as 1,600 feet). Analysis of the water compared with that of the Mediterranean (by Professor Bischoff of Bonn), shows in 10,000 parts :

In 16 ounces, the thermal brine of Oeynhausen contains 319 grains of solid ingredients, viz ::

No trace of iodine has been found, but a considerable amount of bromine, though its precise quantity has not yet been determined. In the chemical manufactory near Neusalzwerk, the bromine is procured from the mother-lye of the salt-water. According to the above analysis the Soole' (salt-spring) may be considered as sea-water modified by the addition of bicarbonates and carbonic acid, besides a higher natural temperature. The water remains clear and transparent, as long as it is conducted in pipes; but exposed for some time to the atmosphere, it gradually loses its carbonic acid and becomes turbid, depositing oxide of iron and carbonate of lime. Three cubic feet of free carbonic acid and other gases (the latter at the rate of six per cent.) escape per minute from the borehole. The absorbed carbonic acid amounts to of the volume of brine, so that forty-three cubic feet of the acid are obtained per minute with the water. Only at the depth of two feet the carbonic acid begins to be evolved at a greater depth it is completely absorbed. The proportion of the free to the combined acid is as one to fifteen. A weak bitter spring near the 'Soole' is frequently used for drinking. It contains in 1,000 parts 19 of solid ingredients—(71⁄2 sulphate of soda, 2 sulphate of magnesia, 3 chloride of sodium, 2 chloride of magnesium, 1 chloride of calcium, 3 bicarbonate of lime, bicarbonate of magnesia).

At present there are sixty-seven baths of different classes, the baignoires of which are fifteen feet below the level of the borehole. The water rises in the bathing-house in a perpendicular shaft to the height of twelve feet, and fills the basins under the pressure of its column from below. At the sides of the baignoires the filling pipes are so contrived that a wave-like motion can be communicated to the bath, so that the stream can be made to enter in one spout, or in numerous fascicular spouts. The carbonic acid can be evolved near the bottom or at the surface of the bath, with quite a different effect on the bather. The mouthpiece of the filling-tap is provided with screw-windings, to which a copper tube may be attached, reaching nearly to the bottom of the basin,

or a bent tube with a leather pipe, or a sieve-like head-piece, according to the intended use. A great importance is attached by the physicians to the kind of bath employed, for one baignoire may exhibit four or five baths of perfectly different physical effects, and these modifications are made use of in the treatment of the respective diseases. For a quiet bath, the side-tap must be closed; the water flows in imperceptibly from the bottom, with a comparatively diminished evolution of carbonic-acid gas, and flows out again as soon as it reaches a certain height, at the other end of the bath. The effect is again different, if the filling-tube be merely held and not screwed to the tap. Atmospheric air entering the water with carbonic acid, the latter rises, continually hissing and foaming; by an ascending tube, wave-like motions are formed on the surface. If the leather pipe or short bent tube be fixed to the side-tap, the stream and evolution of carbonic acid can be directed to any layer of the water or to any part of the body (as douche). If the water is allowed to fall from the tap into the basin, a lively wave-like motion is communicated to the whole mass, with constant development of foam and hissing, and the most complete disengagement of carbonic acid.

Though the energy of the sentient nerves is greatly heightened, and the general metamorphosis and muscular tone stimulated, still no injurious effects are perceived from the carbonic acid, unless some contra-indicating circumstances forbid the use of this form of bath. An extremely pleasurable sensation is created by the water constantly moving to and fro with white foam and hissing. But the titillation produced by the sieve-like douche is certainly the most agreeable sensation that can be imagined, and must inevitably be of great therapeutic value in many diseases of the nervous and sero-fibrous system. A different result is also expected from applying the douche under the water, when the force is diminished, or beyond the level of the bath. The douches are generally followed by the use of rubbing-brushes.

The Soole' is further made use of for a natural vapour-bath.' In consequence of the fall of thirteen feet, to which it is subjected at this distance (thirty-six roods from the borehole), it rises in a shaft to the height of twelve feet, and constantly splashes over, filling the chamber with exhalations of saline ingredients and carbonic acid: the latter tending to move towards the bottom from its gravity, whilst the former remain suspended in the upper strata of the room, exercising their grateful influence on the respiratory organs. The chest seems inclined to expand more freely, with a