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Antimony
When the ore of regulus of antimony is to be decomposed, the first thing to be done is to expose it to a degree of heat too weak to melt its earthy and stony parts, but strong enough to fuse its reguline together with its sulfureous parts, which by this means are separated from the earth and united into one mass known by the name of Antimony.

If equal parts of nitre and Anbitmony be mixed together and the mixture exposed to the action of fire a violend detonation ensues ; the nitre deflagrating consumes the sulfur of the Antimony and even a part of its phlogiston. After the detonation there remains a grayish matter which contains fixed nitre, vitriolated tartar and the reguline part of the Antinmony in some measure deprived of its phlogiston and half vitrified by the action of the fire, which is considerably increased by the deflagration. This matter is called Liver of Antimony. If instead of equal parts of nitre and Antimony two parts ofthe former be used to one of the latter then the reguline parts loses much more of its phlogiston and remains in the form fo a yellowish powder. Again, if three parts of nitre be taken to one of Antimony the Regulus is thereby entirely robbed of its phlogiston and converted to a white calx which bears the name of Diaphoretic Antimnoy or Diaphoretic Mineral. The pearly matter may be precipitated by pouring an acid on the saline substances which here remain after the detonation in the same manner as we shewed above was to be done with regard to the Regulus. In the last two operations where the nitre is in a double or triple proportion to the Antimony the reguline part is found after the detonation to be converted into a calx and not into a half vitrified matter which we have seen is the effect when equal parts only of nitre and Antimony are used. The reason of this difference is that in these two cases the reguline part, being wholly or almost wholly deprived of its phlogiston becomes as was observed, more difficult to fuse and consequently cannot begin to vitrify in the same degree of heat as that which hath not lost so mush of its phlogiston. Ifinstead of performing hte operation with equal parts of nitre and Antimony alone a portion of some substance which abounds with phlogiston be added in that case the sulfur only of the Antimony will be consumed and the Regulus will remain united with its phlogiston and separated from its sulfur. The regulus prepared in this manner is absolutely pure, because no metalline substance being employed none can mix with and adulterate it. It is called Regulus of Antimony per se or only Regulus of Antimony. It is true indeed that in this operation much of the reguline part unavoidably loses its phlogiston and is calcined and consequently a much smaller quantity of Regulus is obtained than when metalline precipitants are employed but this loss is easily repared if it be thought proper by restoring to the calcined part its lost phlogiston. Antimony meled with two parts of fixed alkali yields no Regulus but is entirely dissolved by the salt and forms with it a mass of a reddish yellow color.

The reason why no precipitate is produced on this occasion is that the alkali uniting with the sulfur of the Antimony forms therewith the combination called Liver of Sulfur wich by its ntature is qualified to keep the reguline part dissolved. Theis mass formed by the union of the Antimony with the alkali is soluble in water. If any acid whatever be drops into this solution, there falls a precipitate of a reddish yellow color because the acid unites with the alkali and forces it to quit the matters with which it was combined. This precipitate is called Golden Sulfur of Antimony. As in the operation for preparing Regulus of Antimony perse, some of the nitre is by the inflammable matters added thereto turned to an alkali this alkali seizes on part of the Antimony and therewith forms a compound like that just described. Hence it comes that if the scoria formed in this process be dissolved in water and an acid dropped into the solution a true golden sulfur of Antimony is thereby separated. This union of Antimony with an alkali may also be brought about by the humid way that is by making use of an alkali resolved into a liquor and boiling the mineral in it. The alkaline liquro in proportion as it acts upon the Antimony gradually becomes reddish and turbid. If left to settle and cool when well saturated therewith, it gradually deposites the Antimony it had taken up which precipitates in the form of a red powder and this precipitate is the celebrated remedy known by the name of Kermes mineral. It is plain that the kermes is nearly hte same thing with the golden sulfur yet it differs from it in some respects and especially in this that being taken inwardly it operates much more gently than the golden sulfur which is a violent emetic. Nitre fixed by charcoad and resolved into a liquor is the only alkali employed in preparing the kermes. It was shewn above that Regulus of Antimony mixed and distilled with corrosive sublimate decompounds it disengages the Mercury and joining itself to the marine acid forms therewith a new combination called Butter of Antimony. If the same operation be performed with crude Antimony instead of its Regulus the same effects are produced but then the Antimony itself is also decomposed that is the reguline part is separated from the sulfur which beining set free unites with the Mercury now also at liberty and these two together form a true Cinnabar of Antimony.

Mercury
The vapours of Mercury thus raised by the action of fire being collected and united in a certain quantity appear to be no other than true Mercury, retaining every one of its properties and no experiment hath ever been able to shew the least change thus produced in its nature. If Mercury be exposed to the greatest heat that it can bear without sublimation and continued in it for turns to a red powder a which the Chymists call Mercurius precipitatus per se. But to succeed in this operation it is absolutely necessary that the heat be such as is above specified for this metallic substance may remain exposed to a weaker heat for a considerable number of years without undergoing any sensible alteration. Some Chymists fancied that by this operation they had fixed Mercury and changed its nature but without any reason for it the Mercury thus seemingly transmuted be exposed to a somewhat stronger degree of fire it sublimes and exhales in vapours as usual and those vapours collected are nothing else but running Mercury which has recovered all its properties without the help of

any additament.

Lead
The nitrous acid dissolves this metal with much ease and in great quantites and from this solution a small portion of mercury may be obtained. On this subject see Elements of the Practice of Chymistry.

Sulphur vive
Sulfur is absolutely insoluble in water and in capable of contracting any sort of union with it. It melts with a very moderate degree of heat and sublimes in fine light downy tusts called Flowers of Sulfur. By being thus sublimed it suffers no decomposition let the operation be repeated ever so often so that Sublimed Sulfur or Flower of Sulfur hath exactly the same properties as Sulfur that has never been sublimed.

If equal parts of Sulfur and Alkali be melted together they incorporate with each other ad from their conjuction proceeds a compound of a most unpleasant smell much like that of rotten eggs and of a red color nearly resembling that of an animal liver, which has occasioned it to bear the name of Hepar Sulfuris, or Liver of Sulfur. In this composition the fixed Alkali communicates to the Sulfur the property of dissolving in water and hence it comes that Liver of Sulfur may be made as well when the Alkali is dissolved by water into a fluid as when it is fused by the action of fire. Sulfur has less affinity than any Acid with the fixed Alkalis and therefore Liver of Sulfur may be decompounded by any Acid whatever which will unite with the fixed Alkali form therewith a Neutral Salt and separated the Sulfur. If Liver of Sulfur be dissolved in water and an Acid poured thereon the liquor which was transparent before instantly turns to an opaque white because the Sulfur being forced to quit its union with the Alkali, loses at te same time the property of dissolving in water and appears again in its own opaque form. The Liquor tus made white by the Sulfur is called Milk of Sulfur. If this liquor be suffered to stand still for sometime the particles of Sulfur now most minutely divided gradually approach each other unite and fall insensible to the bottom of the vessel and then the liquor recovers its transparency. The Sulfur thus deposited on the bottom of t he vessel is called t he Magistery or Precipitate of Sulfur. The names of Magistery and Precipitate are also given to all substances whatever that are separated from another by this method which is the reason that we use the expression of precipitating one substance by another to signify the separating one of them by means of the other.

Sea Salt
From what has been said of the union of the Acid of Sea-Salt with a fixed Alkali and of the neutral salt resulting therefrom, it may be concluded that this neutral salt is no other than the common kitchen-salt. But is must be observed that the fixed Alkali which is the natural basis of

the common salt obtained from sea-water, is of a sort somewhat differing from fixed Alkalis in general and hath certain properties peculiar to itself. For 1. The basis of Sea-Salt differs from other fixed Alkalis in this that it crystallizes like a neutral salt. 2. It does not grow moist in the air on the contrary when exposed to the air it loses part of the water that united with it in crystallization by which means its crystals lose their transparency become as it were mealy and fall into a fine flour. 3. When combined with the vitriolic Acid to the point of saturation it forms a neutral salt differing from vitriolated tartar first in the figure of its crystals which are oblong fix-sided solids secondly in its quantity of water which in crystallization unites therewith in a much greater proportion than with vitriolated tartar whence it follows that this salt dissolves in water more readily than vitriolated tartar thirdly in that it flows with a very moderate degree of heat whereas vitriolated tartar requires a very fierce one. If the Acid of Sea-Salt be separated from it basis by means of the vitriolic Acid it is easy to see that when the operation is finished the salt we have been speaking of must be the result. A famous Chymist, named Glauber was the first who extracted the Spirit of Salt in this manner examined the neutral salt resulting from his process and finding it to have some singular properties called it his Sal mirabile or wonderful Salt on this account it is still called Glauber,s Sal mirabile or plainly Glauber,s Salt. 4. When the basis of Sea-Salt is combined with the nitrous Acid to the point of saturation there results a neutral salt or a sort of nitre differing from the common nitre first in that it attracts the moisture of the air pretty strongly and this makes it difficult to crystallize secondly in the figure of its crystals which are parallelopipeds and this has procured it the name of Quadrangular Nitre. Common salt or the neutral salt formed by combining the Marine Acid with this particular sort of fixed Alkali has taste well known to every body. The figure of its crystals is exactly cubical. It grows moist in the air and when exposed to the fire, it bursts before it melts into many little fragments with a crackling noise which is called the Decrepitation of Sea-Salt. That neutral salt mentioned above which is formed by combining the Marine Acid with a common fixed Alkali and called Sal sebrifugum Sylvii, hath also this property.

Iron
Iron being exposed tothe action of fire for some time especially when divided into small particles such as filings is calcinded and loses its phlogiston. By this means it turns to a kind of reddish yellow earth which on account of its color is called Crocus Martis or Saffron of Mars. Water also acts upon Iron and therefore Iron exposed to moisture grows rusty. If Iron-filings be exposed to the dew they turn wholly to a rust which is called Crocus Martis Aperiens. This metal hath a greater affinity than any other metalline substance with sulfur on which account it is successfully used to precipitate and separate all metalline substances combined with sulfur.

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