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The effect was magical. I felt all the enthusiasm of the spot and moment. "This, this," cried I, "is the Rhine!" And, truth to say, he appeared glorious. I was overpaid by these few brief glances the whole long way I had voyaged hither. My imagination had kindled at some unknown beam from one of the many living depositaries of heaven's light around me. I was not standing on earth. Fancy had carried me aloft in fairy flights,—my station, in very deed, some castle built in air. Nor could I well persuade myself that the novel and most superb scene of which from thence I was spectator, and whereto the grand characteristics of the fortress and the inspiriting influence of a garrison off duty were no inconsiderable aids, was not altogether mere illusion;—that such beauties, such enjoyment, could be reality!

Turning our back on this splendid prospect, the height affords a beautiful view inland, commanding for some distance the road that winds through the fertile valley at its base to Ems, and towards which every opening for the artillery is directed with studious and deadly consistency. Over this, the long shadow of the rock threw its deepening folds. I sought again the glowing Rhine. I adore a fine sunset. Here would I have lingered while a spark of day remained, and wishfully anticipated the wondrous scene under the more soothing influence of moonlight. But, alas! I was one only of a party. Besides, the rigid discipline of the place would have forbidden my stay.

We descended. Every mouth was full of the beautiful vision. All expressed themselves highly gratified; but I verily believe none felt half so much so as myself. Adieu, magnificent eyrie of the aigle noir! When henceforth appears the badge of black and white on gateway, staff, or palisade,* I shall renew, however faintly, the enjoyments of this delicious evening, and Ehrenbreitstein shall again be present to the eye, so affectionately retentive, of memory.

Resuming our voyage on the morrow, we had a repetition of the features noticed yesterday; the hills, perhaps, a trifle bolder; the vineyards more continuous, and the turreted ruins generally, some one at least, in prominent view. It must be confessed, the very abundance of the treat operates something like a surfeit; and I felt no disinclination to-day to bury myself for a long hour in the cabin, at the very middling one o'clock table d'hôte: far different were our wines from the produce of the Johannisberg and Steinberg estates we were passing. A little below Mayence, is a palace of the Duke of Nassau. Here the river, which had for some time appeared confined and turbulent, forming several dangerous eddies or whirlpools, expands to thrice its former breadth, while the hills recede on both sides, giving place to a landscapery more like that of home, whose hardly inferior beauties are those of fertility and repose.

I had, by this time, become extremely sociable with most of my Eng

It is usual all over the Continent, to denote any post of the government, especially military ones, by some slight wooden outwork, striped or ringed with the national. colours. The Black Eagle is the emblem of Prussia, and these pickets are painted in white and black.

lish fellow-travellers; had broken the ice of first acquaintance with more than one of the foreign ones; and it was with very altered sentiments that I parted from some of my companions, whom, in the outset of my journey, I had set down as disagreeable and empty or arrogant persons. Make thy note here, reader, to eschew these personal prepossessions as much as possible, especially if their tenor be unfavourable. Experience generally proves them more or less unjust; and whatever the event, they will be admitted, at the least, to be premature.

Mayence, or Mentz, the birth-place of printing, is a great garrison.* The city is better built, and its streets more spacious and cleanly than at Cologne. Of its ancient cathedral, which is scarred and mutilated by besiegers' cannon, the chief ornaments are a series of monuments of the electoral bishops.

CHEMISTRY.

SULPHUR.

SULPHUR, Sometimes called brimstone, is a non-metallic body which has been known from remote antiquity; for, according to Pliny (lib. 35, c. 15), the ancients used it as a medicine, and the fumes of it to bleach wool. It occurs pure, as well as in various states of combination with metals, forming sulphuret of iron, copper, lead, antimony, &c.; it combines with oxygen in various proportions, one of which is sulphuric acid, and this acid combines with lime, as sulphate of lime or gypsum; with barytes as sulphate of barytes; it is also in combination with various other earthy substances; it is found in combination with hydrogen, forming sulphuretted hydrogen gas, which is contained in the Harrowgate and Cheltenham waters. It enters the organic kingdom in albumen and hair.

The most considerable deposite of sulphur is that of Solfatara, near Naples; it is exhaled in large quantities from volcanoes, sometimes in combination with hydrogen, sometimes it condenses in the fissures of mountains, where it is exhaled in combination with hydrogen. The sulphuretted hydrogen is decomposed by the atmosphere, the oxygen of which combines with the hydrogen, forming water. The sulphur is precipitated and forms a deposite on the surface of the earth. Sulphur may be obtained in abundance by distilling bisulphuret of iron, or iron pyrites.

Sulphur may be easily crystallized by melting roll sulphur in a stoneware crucible. Having placed it to cool, as soon as the surface begins to harden, break it and pour out the liquid sulphur from beneath; when quite cold, if the crucible be broken, beautiful needle-shaped crystals will appear. The most liquid state of sulphur is at about 270° or 280°; at a higher temperature it becomes thicker, and at about 480° it will scarcely flow from an inverted vessel; after this to its boiling point,

* For particulars of the place, see "The Rhine, Italy, and Greece." By the Rev. G. N. Wright, M.A., &c.

which is, according to Thompson, 750°, it becomes thinner. At the temperature of 420°, if poured into water, it becomes soft like wax, and readily receives and retains an impression; hence it is useful in making

casts.

If a piece of roll sulphur be held in the hand, it will break, from the sudden warmth, with a cracking noise: in the centre of the roll it is frequently found crystallised.

The flowers of sulphur are obtained by receiving the vapours of heated sulphur in a closed vessel, the temperature of which is below the point of fusion of this substance. It condenses in the vessel in the same manner as the vapour of water condenses in the atmosphere to form snow.

Sulphur, from its ready inflammability, has been long used for woodmatches; and, although so readily inflamed, it may, under particular circumstances, be used to extinguish combustion. Sulphur dropped into a burning chimney will extinguish the flame; this arises from its negative influence, or its property to exhaust of oxygen a confined portion of atmosphere. It is of considerable importance in making gunpowder and other combustibles.

Sulphur combines with oxygen in four proportions, but in none of these directly, with the exception of that of sulphurous acid.

2

Hyposulphurous acid (from vño, under, meaning an açid containing less sulphur than sulphurous acid) (S2 O), or two atoms of sulphur and two of oxygen; sulphurous acid (So) one atom of sulphur and two of oxygen; hyposulphuric acid (S2 O), two atoms of sulphur and five of oxygen; sulphuric acid, or oil of vitriol (Sg), one atom of sulphur and three of

oxygen.

2

Hyposulphurous and hyposulphuric acid are not isolable, that is, they cannot exist unless in combination with some substance as a base; and not being of common occurrence, their description will be deferred. There is no oxide of sulphur, as all its combinations with oxygen possess acid properties.

As it is not likely that the young chemist will wish to prepare sulphuric acid, the process for making it will therefore be given in some future Number. The uses of sulphuric acid are numerous. It is used to prepare chlorine from chloride of sodium (common salt), and also in the formation of many sulphate salts, particularly sulphate of soda, from which, by decomposition, nearly all the carbonate of soda of commerce is prepared. It is also used in bleaching.

Dr. Priestley discovered sulphurous acid as a gas, in which state it commonly is. It is of a very pungent odour, as may easily be ascertained by burning roll sulphur. With the barometer at 45°, it is liquid under the pressure of two atmospheres; at 0°, it is liquid under the pressure of one atmosphere. It possesses considerable bleaching properties, and hence the vapours of burning sulphur or sulphurous acid are used to whiten straw, and to bleach silk, to which they impart a considerable gloss. If a piece of litmus paper be exposed to it, the paper will first become red, then it will be bleached, but commonly the colours are not

destroyed, as they may be restored by the application of a stronger acid, as sulphuric or an alkali. If sulphurous acid gas be respired it causes violent spasms and irritation of the glottis, and even when diluted to a large extent with common air, it causes much uneasiness in the chest. It extinguishes burning bodies, and if a small animal be introduced death

ensues.

To many substances sulphuric acid will yield one part of its oxygen, and upon this principle depends an easy method of making sulphurous acid.

Into a Florence flask put half an ounce of copper, mercury, or charcoal, and upon this pour four liquid ounces of sulphuric acid; upon the application of heat effervescence takes place from the escape of sulphurous acid, the substance acted upon being oxidized with one of the oxygens of the sulphuric acid; the gas escaping may be caught at the mercurial trough; water, which will dissolve about 17 times its volume, may be impregnated by passing the gas into it. Sometimes sulphuric acid gas passed over, or the liquid in the flask containing the acting materials, is thrown out, to prepare the watery solution of sulphurous acid gas free from an admixture of sulphuric acid; and to prevent a failure in the experiment an intermediate bottle is used, according to the annexed diagram. The first bottle contains a small portion of water, to condense any sulphuric acid gas that may pass over; the second bottle is nearly filled with the liquid to be impregnated with sulphurous acid gas.

a

f

9

a, Florence flask, containing sulphuric acid and copper; b, retort stand; c, spirit lamp; d, glass pipe; e, first bottle; f, glass pipe for the passage of the sulphurous acid gas into the receiver, g.

If to a little of the solution Chloride of Barium be added, a white precipitate will fall: this precipitate is soluble in Hydro Chloric acid.

To another part add Acetate of Lead: a white precipitate will fall; this is soluble in nitric acid.

To another part add Protonitrate of Mercury: a gray precipitate of reduced mercury will fall.

To another part add sulphuric acid: sulphurous acid is disengaged. Sulphurous acid may be converted into sulphuric acid by the addition of strong nitric acid, which gives to the sulphurous acid one of its oxygens; being thus converted to sulphuric acid, the quantity of it in solution is easily ascertained by throwing it down with Chloride of Barium, which is a special test for sulphuric acid, an insoluble precipitate of Sulphate of Barytes falls, which is insoluble in acids, and is thus distinguished from the precipitate of sulphurous acid by Chloride of Barium.

VOL. I.-NO. VII.

D D

If sulphuric acid and oxygen gases be mixed in a dry state, and let stand over mercury, they do not combine; if a little water be added, sulphuric acid is formed.

One of the most important of all reagents is sulphuretted hydrogen, which, for chemical purposes, is frequently kept in solution in water.

It is conveniently prepared from Sulphuret of Iron by the action of diluted sulphuric or muriatic acid, which extricates the sulphuretted hydrogen gas. Its smell is exceedingly offensive, resembling that of putrefying eggs. If ignited, it will burn silently or with explosion, according as it has been mixed with atmospheric air or oxygen gas. It tarnishes silver, and other polished metals, and instantly blackens white paint; it is from the exhalations of this gas in small quantities from burning coals, that the white paint of a room becomes discoloured. If the water containing it be exposed to the atmosphere, the hydrogen will be evolved and sulphur precipitated; and if sulphurous acid gas be mixed with sulphuretted hydrogen gas, the oxygen of the former will unite with the hydrogen of the latter and form water: the sulphur will be separated. Sulphuretted hydrogen throws down most of the metallic salts from their solutions, either as a black or a dark brown precipitate.

If it be added to a solution of peroxide of iron, a milk-white precipitate of sulphur falls, and a protoxide of iron is left in solution; thus:

[blocks in formation]

Sulphuretted hydrogen is easily passed into liquid ammonia, the resulting compound is called hydro-sulphuret of ammonia. This is a

valuable reagent to the chemist; as a medicine it is used in cases of Diabetes (dia and Saww, to pass through), and diseases of increased excitement.

Mr. Faraday has reduced this gas to the state of a liquid. (Phil. Trans. 1826, p. 544.) His method was to put muriatic acid and sulphuret of iron into a bent tube, and he so contrived it that they did not come into contact till the tube was hermetically sealed. While the action of acid upon the sulphuret of iron was going on, the tube was surrounded by a freezing mixture of snow and salt. The united action of the pressure and the cold condensed into a liquid the sulphuretted hydrogen, which was evolved: considerable pressure is required to keep it in a fluid state.

Gay Lussac proposed for this gas the name hydro-sulphuric acid, which is generally adopted; but if a chemical name should be descriptive of the elements of the substance, the name sulphuretted hydrogen is preferable. W. W.

Manchester, 6th Sept., 1843.

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