Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/942

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of Bath. The Buxton-waiers break out ih feveral places thereabouts; what is called Buxton-bath takes in feveral warm fprings. Thirty-two yards north eaft of this is St. Anne's well, which is chiefly fupplied from a fpring on its north fide. Twenty yards fouth eaft of St. Anne's, in an- other clofe, is a place where a hot fpring and a cold one rife in the fame receptacle. About fixty-three yards fouth eaft of this is that called Bingham's well, called alfo Leigh's water, from the great benefit a neighbouring gentleman of that name received from it. A little way eaft of this is another ; and in the ftreams of the level that carries the water from the bath, there rifes another very plentiful one ; and about four yards farther eaft there arife three or four

. other fmall ones. From this account, it may eafily be con- ceived that there can be no great difference between the waters of thefe feveral fprings, though on trials they feem to yield different portions of falts and fediments ; at the ut- moft, their difference can be only in degree. The di {tempers they are recommended in, arc the rheuma- tifm, gout, fcurvy, wandering pains, cramps, convulfions, dry afthmas, want of apetite, indigeftions, contractions, ftiffnefs and lamenefs of the limbs, fuppreffibn of the menfes, and all ftoppages and beginning obftructions. As to the difference of age and fex in patients, there is little caution required in the drinking them, except that they mould be taken more fparingly by young people, be- tween the ages of twenty-three and thirty, if very full of blood and juices, and by women with child in their firft and laft months.

As to the method of ufing them, except the body be cof- tive, and the firft paflages furred up with grofs humors, it is not only unneceffary, but hurtful, to prepare the body for them, as it is called, by purging; or at leafl by any ftronger purges than manna, cream of tartar, and the like. The heat of Buxton-waters, in frofty weather, is equal to that of common river water with which two fifths of boil- ing water has been immediately mixed. Sec Short's Hift. of Min. JVat.

&*- Water. Authors, who write with accuracy of fea- water, diftinguifh it as to its degrees of faltnefs and virtues, according to the nature of the feas where it is taken, and the depths from which it is drawn up. Count Marfigli al- ways divides the waters of a deep fea into three portions, the upper, the middle, and the deep: each of thefe, according to him, reach to one third of the depth of the bed of water

- from the fuperficies to the bottom., The upper water he finds greatly to differ from the lower or deep water in its qualities and ftrength, but the middle portion to be always

. more nearly allied to one of the others ; he therefore never

, takes any notice of the middle portion, but makes all his ©bfervations of the differences of fea-zvater from the upper and lower portions.

The fea-water is brighter and clearer than that of any river or pond, but this is not feen, as the whole body of it is viewed together, becaufe then many various colours are reflected from its furface; but on taking up a large glafs of it, and fetting it in a ftill place, it is feen to have none of all the whole feries of its colours when viewed at fea, being intirely owing to its motion, and the different reflections its

. waves have in different angles and directions.

The fea-water appears indeed coloured in its fuperficial part in fonie places, particularly about the mouths of large rivers ; but this is not of its own nature, but is merely owing to the foul water of thefe rivers mixing itfelf with it, they be-

ing frequently yellowifh or bluifh, fometimes blackifh, from

the quantity of dirt they contain, or the various earthy par- ■ tides which they wafh off from their banks and bottoms in their paflage.

As thefe frefh waters principally mix themfelves with the fuperficial part of the fea-water y they extend themfelves a . great way, and give a foulnefs to the upper part of a vaft quantity of fea-water, whofe bottom part is all the while perfectly clear. Thefe foul waters of rivers extend them-

. felves alfo farther, or a lefs way into the fea, according to the way the wind fits; for if the wind blows directly into the mouth of the river, the furface is difturbed in fuch a

-. direction, that the frefh zvater is beaten under, and blends itfelf below as well as above, and therefore tinges the fur- face for a much lefs extent : but if, on the contrary, the wind fits directly from the river, all its waters are blown on, without finking fo deep as they otherwife would, and the foulnefs is extended over a large furface, though it is

■ not fo confiderable in degree.

The water of the fea taken up at great depths, is generally clear and bright, as has been obferved ; but this is not al- ways the cafe, for in fome places a quantity of it taken up in very deep water, and that near the bottom, is found fouled in the fame manner as the fuperficial part is near the mouths of large rivers ; and this, when ftrictly inquired into, is

■ found to proceed from the fame caufe, the mixing of a foul river water loaded with particles of earth, which it has

■ wafhed off from the fubftances it palled thi-jugh, and con-

- taining large quantities of blue, black, or yellow earth, all which it would fuffer to fubfide, if fet by for a time in a

WAT

ftill place. Count Marfigli has proved, that as rivers burft up in many places out of the furface of the dry ground* fo they do alfo in feveral parts of the bottom of the fea: in thefe places they pour in their whole body of frefh water, which is fouler than that of our common rivers, becaufe, in its fubterranean paftage, it has been furrounded on all parts with earth, and confined to a much fouler channel. The foul waters thefe mouths of rivers difcharge from the bottom upwards into the fea-water, cannot but act upon that clear liquor, in the fame manner as the fuperficial waters do on the furface, and both muft be fouled alike. This author has particularly defcribed one of thefe fubterranean rivers opening into the fea from his own obfervations. This foul- nefs in fhallow water is fometimes feen through the clearer fuperficial part by the naked eye, and often, befide this, an obferver thinks he fees many other colours in m\&-zvatc r ; but thefe are, for the moft part, not inherent in the water, but are formed by the reflections of the clouds, &c. The fea'waier being naturally clear, in deep places where it is not difturbed it appears blue, but in fhallower water it often has different colours, which are owing to the reflections of the coloured matter at the bottom, which will give a tinge to the water in places, where not fo near the eye as to be diitinctly feen themfelves. The clouds alfo give a fort of coloured appearance to the furface of the fea-water, in re- gard to our eye, though the water itfelf be really colourlefs as that of the pureft fpring. We have a familiar inftance of this in the white look of the fea-water in the fouth feas at certain times : and, on the contrary, when zny thing fouls the fea-water, and gives it a dufky colour, the clouds above add greatly to that appearance. This we fee in the Euxine, which being very deep would naturally appear blue if the water were clear, but as it is often fouled with dufky matter, and clouds are frequent over it, it appears for a great part of the year abfolutely black, and has thence ob- tained the name of the Black fea.

Count MarfigH commemorates alfo another fmgular inftance of this effect of the clouds on the colour of the fea-water, which fell within his own obfervation. Being at the port of Caflis on the feventeenth of December, in the year 1706, at about an hour before fun-fet, there arofe a large cloud of a blood-red colour, of the nature of thofe ufual in fome evenings about fun-fet, but accidentally very large, and ftrongly coloured : as this extended itfelf above, ihe fea-water under it appeared of the fame colour, and looked as red as blood for a great extent, ftill fpreading the fame blood co- lour farther as the cloud extended. This remarkable phse- nomenon lafted till the darknefs hid it; and the people of the place, who faw the fea blood coloured, paid no attenti- on to the cloud above that caufed this colour, but looked on it as a miraculous prefage of war and bloodfhed. As the clouds in many cafes thus evidently give colour to the fea-water, in regard to our eye, fo the fun does the fame thing in many others : but in all thefe cafes it is to be ob- ferved, that the colours are fo far from being real, that the water is all the time clear, pellucid, and colourlefs ; only its different reflections, from thefe different occafions, prefent our eyes with colours, as the colourlefs glafs prifm, or the cut fide or edge of a common looking-glafs does. The fun, as it fhines with different force at different times, gives different tinges to the water, by fhewing more or lefs plainly the fubftances which are at its bottom. This is evi- dent from a familiar experiment of this author's, who fifh- jng on the coafts with a live bait, which was a fmall red fifh, and with a red line, obferved, that when he let down his bait into the water,' in places where the rocks kept eft" the fun's rays, he could only fee his fifh at the depth, of feven yards ; but that even there the fifh and the line both appeared white, having loft to the eye their natural red co- lour : and that, on the contrary, when he let down the bait on the other fide of the rock where the fun fhone, he could, fee it perfectly plain at the depth of eleven yards ; and at that greater depth, both the fifh and the line appeared- o£ their natural red colour. It is evident from this, in how great a degree the fun's rays affect the water in the fhew- ing its contents ; and it is very evident alfo, that upon this principle alone the fame fea, with a coloured bottom, at fome moderate depth, muft appear coloured by that bottom in funfhiny weather, and not at all fo in cloudy. Befide the clouds, the fun, the foulnefs of rivers, and the different bottoms, it is certain that the winds alfo contribute greatly to give the colours we obferve in fea-water. A tempeft in the winter feafon, an hour or two before fun- fet, will fhew all the colours that fea-water is capable of giving, and that without any other accident whatever to aflift in it. The waves in this cafe ftriking violently againft one another, beat off from each other a great number of globules of water, and thefe are thrown up to different heights and diftances ; then as the fun, now low and near the horizon, darts its rays obliquely upon them, they form feveral little rainbows, which are of greater and lefs extent, and of more or lefs duration, according to the circumftances of their afcent. The frefh water of fome large rivers is alfo found to have, in particular places, the fame effect where

the