Imatges de pÓgina

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.

Hyposulphurous acid (from úto, under, meaning an acid containing less sulphur than sulphurous acid) (S, 0,), or two atoms of sulphur and two of oxygen ; sulphurous acid (SO) one atom of sulphur and two of oxygen; hyposulphuric acid (S, 05), two atoms of sulphur and five of oxygen ; sulphuric acid, or oil of vitriol (Sp), one atom of sulphur and three of oxygen.

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

ich, 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


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, Florence flask, containing sulphuric acid and copper; 6, 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.



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 :

2 Irons

Protox.of Iron.
Peroxide of Iron

2 Oxygens

Sulphuretted hydrogen =


Precipitates. 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 Balvw, 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.

Manchester, 6th Sept., 1843.

W. W.




“ Impress Indelible, Death's image on his heart,

Bleeding for others, trembling for himself."-Young, THERE are certain periods in the life of man, which sometimes appear like unbidden guests, and leave an impression on the memory which after events can never wholly efface-periods which stand so prominent in the path we have trod, that on looking back we discern them standing as we met. Some of these periods afford us matter for much joy, both at the time they happen and in after years; others seem to start like spectres in our way, only to afford sorrow and pain; and others have so much of joy and sorrow mingled, as to produce both extremes according to the light in which they are viewed. The death of friends sometimes partakes of each description. Rarely, indeed, can we view their death with unmixed joy, but sometimes we can. When, for instance, some dear friend, after suffering the greatest pain for a length of time, with no prospect of relief on this side the grave, having tears and sorrows for his meat, is at last released by death, with the glorious hope of immortality, we can sometimes look upon his death with joy. When, if our own wishes for his life were granted, they would only be accompanied with suffering and distress, we are sometimes able to sacrifice joyfully our own feeling and desires, in the assurance that our friend's sufferings are o'erhis pains and griefs for ever gone-his tears for ever wiped away. What joy vuld we experience, though he were still spared, when our continually rent with anguish as we behold his sufferings—when every moment which adds to his suffering here, also keeps him from the enjoyment of heaven? Far be it from any one to desire the death of friends in such circumstances, let God's will be done ; but need they sorrow when it is His will to release them from their pain? Our grief is thus dried up in the joy we experience; and, every time memory carries us back to their death-bed, our enfeebled faith is strengthened, and we strive, in the words of scripture, “to live the life of the righteous that our latter end may be like his.” When we are ourselves in suffering and distress, we are often rejoiced amidst our tears when we think of the faith and patience of the departed, and their dying examples speak in words of comfort and of power. When our journey in life is embittered with painful trials—when our hearts are deeply pierced with many sorrows-we are encouraged to bear up against them when we think of those

“Not lost but gone before.” As when a man, journeying on a dreary road under great privations, is encouraged to persevere when he remembers he is going to his father's home, where he will meet those friends who have travelled the sanie road before ; so, the death of friends in these circumstances may often communicate joy to our breasts and chase our sighing and sorrow away.




But the death of friends may sometimes be the cause of the greatest

A friend may die when he is most needed-such as a dear parent; father and mother may both become the prey of the “ insatiate archer," and we, mayhap left in the days of youth, surrounded with many temptations, yet no one from whom we can receive advice, or to whom we can, with confidence, embosom our souls. Or it may be that the husband is deprived of the wife of his bosom-the partner of his cares and of his joys—when he most required her sweet advice and her many tender endearments to soothe him amidst his cares, or when her love and watchful care were required for the objects of her affections in their helpless days. Or it may be that the wife is deprived of her husbandher stay and comfort—and left, perhaps, to toil and suffering and tears ; or it may be that, as a widow, she is deprived of her “only son," on whom she centred her affections, to whom she looked forward for support in her declining years, whose hand she fondly hoped should smooth her dying pillow and lay her honoured head with reverence in the tomb. In these and many other like cases is the death of friends sorrowful—the heart throbs with convulsive emotion, and almost chokes the utterance with its sighs and sobs. Oh! how these occasions furrow the brow and make the head hoary before the time! No smile lights up the countenance -we go along the streets with our heads hanging down-strength seems departed from us—former pleasures can give us no relief-they make our grief still more grievous. Every object which belonged to the departed reminds us of them, and opens anew the fountain of our tears. How we then think of them! How many graces we see in their characters which we formerly overlooked! We think that if we had them again with us, we would treat them with more kindness and love-no unkind word would ever pass our lips, nor would we harbour an unkind thought regarding them.

Sorrow, deep sorrow, may follow the death of friends in such cases, but with how much greater sorrow are we afflicted, should there be “ hope in their death”-if their lives have been stained with crime, and they have gone to the grave without repentance or peace. We can easily imagine the not unfrequent occurrence (alas ! that it should be so) of a “prodigal son,” drawn away by the solicitations of evil companions, enticed by the glowing scenes which imagination has pictured, but experience proves to be false. We can imagine him casting off parental restraint, deaf alike to the commands and entreaties of his loving parents, treating their tears with mockery and their admonitions with disdain. Can we conceive the grief which eats away the peace of his parents' hearts, as they find all the anxiety with which they watched him in infancy abused, and the fond hopes they cherished of him entirely blasted? Who can paint the grief of the mother on whose breast he hung in infancy, and for whom so many prayers were breathed to Heaven? Who can paint the father's grief? His brow is marked with it : his sleepless nights, his secret moments, should tell, with too convincing power, the sorrow of his heart. What consolation, then, can


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