(Catharine), was the eldest daughter of Sir Thomas Parr of Kendal. She was first married to John Nevil, lord Latynner; after whose death she so captivated her amorous sovereign, that he raised her to the throne. The royal nuptials were solemnized at Hampton Court on the 12th of July 1543. Being religiously disposed, she was, in the early part of her life, a zealous observer of the Romish rites and ceremonies; but in the dawning of the Reformation, she became as zealous a promoter of the Lutheran doc-

tine; yet with such prudence and circumspection as her perilous situation required. Nevertheless, we are told, that she was in great danger of falling a sacrifice to the Popish faction, the chief of whom was Bishop Gardiner: he drew up articles against her, and prevailed on the king to sign a warrant to remove her to the Tower. This warrant was, however, accidentally dropped, and immediately conveyed to her majesty. What her apprehensions must have been on this occasion may be easily imagined. She knew the monarch, and she could not help recollecting the fate of his former queens. A sudden illness was the natural consequence. The news of her indisposition brought the king to her apartment. He was lavish in expressions of affection, and sent her a physician. His majesty being soon after also somewhat indisposed, she prudently returned the visit; with which the king seemed pleased, and began to talk with her on religious subjects, proposing certain questions, concerning which he wanted her opinion. She answered, that such profound speculations were not suited to her sex; that it belonged to the husband to choose principles for his wife; the wife's duty was, in all cases, to adopt implicitly the sentiments of her husband: and as to herself, it was doubly her duty, being blessed with a husband who was qualified, by his judgment and learning, not only to choose principles for his own family, but for the most wise and knowing of every nation. "Not so, by St Mary," replied the king; "you are now become a doctor, Kate, and better fitted to give than receive instruction." She meekly replied, that she was sensible how little she was intitled to these praises; that though she usually declined not any conversation, however sublime, when proposed by his majesty, she well knew that her conceptions could serve to no other purpose than to give him a little momentary amusement; that she found the conversation a little apt to languish when not revived by some opposition, and she had ventured sometimes to feign a contrariety of sentiments, in order to give him the pleasure of refuting her; and that she also proposed, by this innocent artifice, to engage him into topics whence she had observed, by frequent experience, that she reaped profit and instruction. "And is it so, sweetheart?" replied the king; "then we are perfect friends again." He embraced her with great affection, and sent her away with assurances of his protection and kindness.

The time being now come when she was to be sent to the Tower, the king, walking in the garden, sent for the queen, and met her with great good humour; when lo the chancellor, with forty of the guards, approached. He fell upon his knees, and spoke softly with the king, who called him knave, arrant knave, beast, fool, and commanded him instantly to depart. Henry then returned to the queen, who ventured to intercede for the chancellor: "Ah, poor soul," said the king, "thou little knowest how evil he deserveth this grace at thy hands. Of my word, sweetheart, he hath been toward thee an arrant knave; and so let him go." The king died in January 1547, just three years and a half after his marriage with this second Catharine; who in a short time was again espoused to Sir Thomas Seymour lord-admiral of England: for in September which he thought would be attended with a lasting peace between the two empires, received the ambassadors with all possible marks of honour, and readily complied with their request. Soon after, Caracalla sent a second embassy to acquaint the king that he was coming to solemnize the nuptials; whereupon Artabanus went to meet him attended with the chief of the nobility and his best troops, all unarmed, and in most pompous habits: but this peaceable train no sooner approached the Roman army, than the soldiers, on a signal given them, falling upon the king's retinue, made a most terrible slaughter of the unarmed multitude, Artabanus himself escaping with great difficulty. The treacherous Caracalla, having gained by this exploit great booty, and, as he thought, no less glory, wrote a long and boasting letter to the senate, assuming the title of Parthicus for this piece of treachery; as he had before that of Germanicus, for murdering, in like manner, some of the German nobility.

Artabanus, resolving to make the Romans pay dear for their inhuman and barbarous treachery, raised the most numerous army that had ever been known in Parthia, crossed the Euphrates, and entered Syria, putting all to fire and sword. But Caracalla being murdered before this invasion, Macrinus, who had succeeded him, met the Parthians at the head of a mighty army, composed of many legions, and all the auxiliaries of the states of Asia. The two armies no sooner came in sight of each other, but they engaged with the utmost fury. The battle continued two days; both Romans and Parthians fighting so obstinately, that night only parted them, without any apparent advantage on either side; though both retired when night had put an end to the contest, crying, Victory, victory. The field of battle was covered all over with dead bodies, there being already above 40,000 killed, including both Romans and Parthians: nevertheless Artabanus was heard to say, that the battle was only begun, and that he would continue it till either the Parthians or Romans were all to a man cut in pieces. But Macrinus, being well apprised that the king came highly enraged against Caracalla in particular, and dreading the consequences which would attend the destruction of his army, sent an herald to Artabanus, acquainting him with the death of Caracalla, and proposing an alliance between the two empires. The king, understanding that his great enemy was dead, readily embraced the proposals of peace and amity, upon condition that all the prisoners who had been taken by the treachery of Caracalla should be immediately restored, and a large sum of money paid him to defray the expenses of the war.

These articles being performed without delay or hesitation, Artabanus returned into Parthia, and Macrinus to Antioch.

As Artabanus lost on this occasion the flower of his army, Artaxerxes, a Persian of mean descent, but of great courage and experience in war, revolting from the Parthians, prevailed on his countrymen to join him, and attempt the recovery of the sovereign power, which he said they had been unjustly deprived of, first by the Macedonians, and afterwards by the Parthians their vassals. Artabanus, upon the news of this revolt, marched with the whole strength of his kingdom to suppress it; but being met by Artaxerxes at the head of a no less powerful army, a bloody battle ensued, which is said to have lasted three days. At length the Parthians, though they behaved with the utmost bravery, and fought like men in despair, were forced to yield to the Persians, who were commanded by a more experienced leader. Most of their troops were cut off in the flight; and the king himself was taken prisoner, and soon after put to death at Artaxerxes's order. The Parthians, having lost in this fatal engagement both their king and their army, were forced to submit to the conqueror, and become vassals to a nation which had been subject to them for the space of 475 years.

For an account of the manners, customs, &c. of the ancient Parthians, see the article Persia.

PARTI, PARTIE, Party, or Parted, in heraldry, is applied to a shield or escutcheon, denoting it divided or marked out into partitions.

Parti per pale, is when the shield is divided perpendicularly into two halves, by a cut in the middle from top to bottom.

Parti per fess, is when the cut is across the middle from side to side.

Parti per bend dexter, is when the cut comes from the upper corner of the shield on the right hand, and descends athwart to the opposite lower corner.

Parti per bend sinister, is when the cut, coming from the upper left corner, descends across to the opposite lower one.

All these partitions, according to M. de la Colombiere, have their origin from the cuts and bruises that have appeared on shields after engagements; and, being proofs of the dangers to which the bearers had been exposed, they gained them esteem; for which reason they were transmitted to posterity, and became arms and marks of honour to their future families.

PARTIALITY. See Self-partiality and Prejudice.

PARTICIPLE, in grammar, an adjective formed of a verb; so called, because it participates partly of the properties of a noun, and partly of those of a verb. See Grammar.

PARTICLE, in physiology, the minute part of a body, an assemblage of which constitutes all natural bodies.

In the new philosophy, particle is often used in the same sense with atom in the ancient Epicurean philosophy, and corpuscle in the latter. Some writers, however, distinguish them; making particle an assemblage or composition of two or more primitive and physically indivisible corpuscles or atoms; and corpuscle, or little body, an assemblage or mass of several particles or secondary corpuscles. The distinction, however, is of little moment; and, as to most purposes of physics, particle may be understood as synonymous with corpuscle. Particles are then the elements of bodies: it is the various arrangement and texture of these, with the difference of the cohesion, &c. that constitute the various kinds of bodies, hard, soft, liquid, dry, heavy, light, &c. The smallest particles or corpuscles cohere with the strongest attractions, and always compose bigger particles of weaker cohesion; and many of these cohering compose bigger particles, whose vigour is still weaker; and thus on for divers successions, till the progression end in the biggest particles, whereon the operations in chemistry, and the colours... Particle.

colours of natural bodies, depend, and which, by cohering, compose bodies of sensible bulks.

The cohesion of the particles of matter, according to the Epicureans, was effected by hooked atoms; the Aristotelians thought it managed by ret, that is, by nothing at all. But Sir Isaac Newton shows it is done by means of a certain power, whereby the particles mutually attract or tend towards each other, which is still perhaps giving a fact without the cause. By this attraction of the particles he shows that most of the phenomena of the lesser bodies are affected, as those of the heavenly bodies are by the attraction of gravity. See Attraction and Cohesion.

Particle, a term in theology, used in the Latin church for the crumbs or little pieces of consecrated bread, called in the Greek church μελίτης. The Greeks have a particular ceremony, called τον μελίτην, of the particles, wherein certain crumbs of bread, not consecrated, are offered up in honour of the Virgin, St John Baptist, and several other saints. They also give them the name of ἀγωνισμός, oblation. Gabriel archbishop of Philadelphia wrote a little treatise εἰπεῖ τῶν μελίτων, wherein he endeavours to show the antiquity of this ceremony, in that it is mentioned in the liturgies of St Chrysostom and Basil. There has been much controversy on this head between the reformed and catholic divines. Aubertin and Blondel explain a passage in the theory of Germanus patriarch of Constantinople, where he mentions the ceremony of the particles as in use in his time, in favour of the former; Messieurs de Port Royal contest the explanation; but M. Simon, in his notes on Gabriel of Philadelphia, endeavours to show that the passage itself is an interpolation, not being found in the ancient copies of Germanus, and consequently that the dispute is very ill grounded.

Organic Particles, are those small moving bodies which are imperceptible without the help of glasses; for besides those animals which are perceptible to the sight, some naturalists reckon this exceedingly small species as a separate class, if not of animals properly so called, at least of moving bodies, which are found in the semen of animals, and which cannot be seen without the help of the microscope. In consequence of these observations, different systems of generation have been proposed concerning the spermatic worms of the male and the eggs of the female. In the second volume of Buffon's Natural History, several experiments are related, tending to show that those moving bodies which we discover by the help of glasses in the male semen are not real animals, but organic, lively, active, and indestructible molecules, which possess the property of becoming a new organized body similar to that from which they were extracted. Buffon found such bodies in the female as well as in the male semen; and he supposes that the moving bodies which he observed with the microscope in infusions of the germs of plants are likewise vegetable organic molecules. Needham, Wrisberg, Spallanzani, and several other writers on the animal economy, have pursued the same tract with M. de Buffon.

Some suppose that these organic molecules in the semen answer no purpose but to excite the venereal desire; but such an opinion cannot be well founded; for eunuchs, who have no seminal liquor, are nevertheless subject to venereal desire. With respect to the Particles, beautiful experiments which have been made with the microscope on organic molecules, M. Bonnet, that learned and excellent observer of nature, remarks that they seem to carry us to the farthest verge of the sensible creation, did not reason teach us that the smallest visible globule of seminal liquor is the commencement of another universe, which, from its infinite smallness, is beyond the reach of our best microscopes. —Animalules, properly so called, must not be confounded with the wonderful organic particles of Buffon. See Animalule.

Particle, in grammar, a denomination for all those small words that tie or unite others, or that express the modes or manners of words. See Grammar.

Parting, in metallurgy. See Metallurgy.

Parting, in chemistry, an operation by which gold and silver are separated from each other. As these two metals resist equally well the action of fire and of lead, they must therefore be separated by other methods. This separation could not be effected if they were not soluble by different menstruums.

Nitrous acid, marine acid, and sulphur, which cannot dissolve gold, attack silver very easily; and therefore these three agents furnish methods of separating silver from gold, or of the operation called parting.

Parting by nitrous acid is the most convenient, and therefore most used, and even almost the only one employed by goldsmiths and coiners. Wherefore it is called simply parting. That made with the marine acid is only made by cementation, and is known by the name of concentrated parting. Lastly, parting by sulphur is made by fusion, which the chemists call the dry way, and is therefore called dry parting.

Parting by Aquafortis. Although parting by aquafortis be easy, as we have said, it cannot however succeed or be very exact, unless we attend to some essential circumstances.

1. The gold and silver must be in a proper proportion: for if the gold was in too great quantity, the silver would be covered and guarded by it from the action of the acid.

Therefore, when assayers do not know the proportion of these two metals in the mass to be operated upon, they discover it by the following method.

They have a certain number of needles composed of gold and silver alloyed together in graduated proportions, and the alloy of each needle is known by a mark upon it. These are called proof needles.

When assayers want to know nearly the proportion of gold and silver in a mass, they rub this mass upon a touchstone, so as to leave a mark upon it. They then make marks upon the touchstone with some of the needles the colour of which they think comes nearest to that of the mass. By comparing the marks of these needles with the mark of the mass, they discover nearly the proportion of the gold and silver in the mass.

If this trial shows, that in any given mass the silver is not to the gold as three to one, this mass is improper for the operation of parting by aquafortis. In this case, the quantity of silver necessary to make an alloy of that proportion must be added.

This operation is called quartation, probably because it reduces the gold to a fourth part of the whole mass.

2. That the parting may be exact, the nitrous acid or aquafortis employed must be very pure, and especially free from mixture of vitriolic and marine acids. For if this was not attended to, a quantity of silver proportionable to these two foreign acids would be separated during the solution; and this portion of silver reduced by these acids to vitriol of silver and to luna cornea would remain mingled with the gold, which consequently would not be entirely purified by the operation.

When the metallic mass is properly allayed, it is to be reduced to plates, rolled up spirally, called cornets; or to grains. These are to be put into a matras, and upon them a quantity of aquafortis is to be poured, the weight of which is to that of the silver as three to two; and as the nitrous acid employed for this operation is rather weak, the solution is assisted, especially at first, by the heat of a sand bath, in which the matras is to be placed. When, notwithstanding the heat, no further mark of solution appears, the aquafortis charged with silver is to be decanted. Fresh nitrous acid is to be poured into the matras, stronger than the former, and in less quantity, which must be boiled on the residuum mass, and decanted as the former. Aquafortis must even be boiled a third time on the remaining gold, that all the silver may be certainly dissolved. The gold is then to be washed with boiling water. This gold is very pure if the operation has been performed with due attention. It is called gold of parting.

No addition of silver is required, if the quantity of silver of the mass is evidently much more considerable than that of the gold: persons who have not proof needles and other apparatus to determine the proportion of the alloy, may add to the gold an indeterminate quantity of silver, observing that this quantity be rather too great than too small, and so considerable as to render the mass nearly as white as silver; for a large quantity of silver is rather favourable than hurtful to the operation: It has no other inconvenience than an useless expense, as the larger the quantity is of silver the more aquafortis must be employed. We ought to attend to this fact, that the colour of gold is scarcely perceptible in a mass two-thirds of which is silver and one-third is gold; this colour then must be much less perceptible when the gold is only one-fourth part, or less, of the whole mass.

If the quantity of gold exceeds that of the silver, the mass may be exposed to the action of aqua-regia, which would be a kind of inverse parting, because the gold is dissolved in that menstruum, and the silver is not, but rather reduced to a luna cornea, which remains in form of a precipitate after the operation. But this method is not much practised, for the following reasons.

First, the gold cannot be easily separated from the aqua-regia; for if the parting has been made with an aqua-regia prepared with sal-ammoniac, or if the gold be precipitated by a volatile alkali, this gold has a fulminating quality, and its reduction requires particular operations. If the aqua-regia has been made with spirit of salt, and the precipitation effected by a fixed alkali, the gold will not then be fulminating, but the precipitation will be very slow, and probably incomplete.

Secondly, in the parting by aqua-regia, the silver is indeed precipitated into a luna cornea, and thus separated; but this separation is not perfect, as a small quantity of luna cornea will always remain dissolved by the acids, if this solution even could be only effected by the superabundant water of these acids. Accordingly the silver is not so accurately separated from the gold by aqua-regia, as the gold is from the silver by aquafortis.

The gold, after the parting by aquafortis, is much more easily collected when it remains in small masses than when it is reduced to a powder.

When the mass has been regularly quartered, that is, when it contains three parts of silver and one part of gold, we must employ, particularly for the first solution, an aquafortis so weakened that heat is required to assist the solution of the silver; by which means the solution is made gently; and the gold which remains preserves the form of the small masses before the solution. If the aquafortis employed were stronger, the parts of the gold would be diffused and reduced to the form of a powder, from the activity with which the solution would be made.

We may indeed part by aquafortis a mass containing two parts of silver to one part of gold: but then the aquafortis must be stronger; and if the solution be not too much hastened, the gold will more easily remain in masses after the operation. In both cases, the gold will be found to be tarnished and blackened, probably from what was lately called the phlogiston of the nitrous acid. Its parts have no adhesion together, because the silver dissolved from it has left many interstices; and the cornets or grains of this gold will be easily broken, unless they be handled very carefully. To give them more solidity, they are generally put into a test under a muffle and made red-hot; during which operation they contract considerably, and their parts are approximated. These pieces of gold are then found to be rendered much more solid, so that they may be handled without being broken. By this operation also the gold resumes its colour and lustre; and as it generally has the figure of cornets, it is called gold in cornets, or grain gold. Essayers avoid melting it, as they choose to preserve this form, which shows that it has been parted.

The gold and silver thus operated upon ought to have been previously refined by lead, and freed from all alloy of other metallic matters, so that the gold which remains should be as pure as possible. However, as this is the only metal which resists the action of aquafortis, it might be purified by parting from all other metallic substances; but this is not generally done, for several reasons. First, because the refining by lead is more expeditious and convenient for the separation of the gold from the imperfect metals; secondly, because the silver, when afterwards separated from the aquafortis, is pure; lastly, because most imperfect metals do not remain completely and entirely dissolved in nitrous acid, from the portion of phlogiston which this acid deprives them of, the gold would be found after the parting mixed with the part of these metals which is precipitated.

The gold remaining after the parting ought to be well washed, to cleanse it from any of the solution of silver which might adhere to it; and for this purpose distilled water ought to be used, or at least water the purity of which has been ascertained by its not forming a precipitate with a solution of silver, because such a precipitate would alter the purity of the gold.

The silver dissolved in the aquafortis may be separated either by distillation, in which case all the aquafortis is recovered very pure, and fit for another parting; or it may be precipitated by some substance which has a greater affinity than this metal with nitrous acid. Copper is generally employed for this purpose at the mint.

The solution of silver is put into copper vessels. The aquafortis dissolves the copper, and the silver precipitates. When the silver is all precipitated, the new solution is decanted, which is then a solution of copper. The precipitate is to be well washed, and may be melted into an ingot. It is called parted silver. When this silver has been obtained from a mass which had been refined by lead, and when it has been well washed from the solution of copper, it is very pure.

Mr. Cramer observes justly in his Treatise on Assaying, that however accurately the operation of parting has been performed, a small portion of silver always remains united with the gold, if the parting has been made by aquafortis; or a small portion of the gold remains united with the silver, if the parting has been made by aqua regia: and he estimates this small alloy to be from a two hundredth to a hundred and fiftieth part; which quantity may be considered as nothing for ordinary purposes, but may become sensible in accurate chemical experiments. Chem. Ditt.

The mass of gold and silver to be parted ought previously to be granulated; which may be done by melting it in a crucible, and pouring it into a large vessel full of cold water, while at the same time a rapid circular motion is given to the water by quickly stirring it round with a stick or broom.

The vessels generally used for this operation, called parting-glasses, have the form of truncated cones, the bottom being commonly about seven inches wide, the aperture about one or two inches wide, and the height about 12 inches. These glass-vessels ought to have been well annealed, and chosen free from flaws; as one of the chief inconveniences attending the operation is, that the glasses are apt to crack by exposure to cold, and even when touched by the hand. Some operators secure their glasses by a coating. For this purpose they spread a mixture of quicklime flaked with beer and whites of eggs upon linen cloth, which they wrap round the lower part of the vessel, leaving the upper part uncovered, that they may see the progress of the operation; and over this cloth they apply a composition of clay and hair. Schlutter advises to put the parting-glasses containing some water, and supported by trevets, with fire under them. When the heat communicated by the water is too great, it may be diminished by adding cold water, which must be done very carefully by pouring against the sides of the pan, to prevent too sudden an application of cold to the parting-glasses. The intention of this contrivance is, that the contents of the glasses, if these should break, may be received by the copper vessel. Into a glass 15 inches high, and 10 or 12 inches wide at bottom, placed in a copper-pan 12 inches wide at bottom, 15 inches wide at top, and 10 inches high, he usually put about 80 ounces of metal, with twice as much aquafortis.

The aquafortis ought to be so strong as to be capable of acting sensibly on silver when cold, but not so strong as to act violently. If the aquafortis be very strong, however pure, and if the vessels be well closed, a small quantity of the gold will be dissolved along with the silver, which is to be guarded against.

Little heat ought to be applied at the beginning, the liquor being apt to swell and rise over the vessel; but when the acid is nearly saturated, the heat may be safely increased.

When the solution ceases, which may be known by the discontinuance of the effervescence, or emission of air-bubbles, the liquor is to be poured off. If any grains appear entire, more aquafortis must be added, that all the silver may be dissolved. If the operation has been performed slowly, the remaining gold will have still the form of distinct masses, which are to receive solidity and colour by fire, in the manner directed by the author of the dictionary. If the operation has been performed hastily, the gold will have the appearance of a black mud or powder, which after five or six washings with pure water must be melted.

The silver is usually recovered by precipitating it from the aquafortis by means of copper vessels into which the liquor is poured, or of plates of copper which are thrown along with the liquor into glass-vessels. A considerable heat is required to accelerate this precipitation. Dr. Lewis says, he has observed that when the aquafortis was perfectly saturated with silver, no precipitation was occasioned by plates of copper, till a drop or two of aquafortis was added to the liquor, and then the precipitation began and continued as usual.

The precipitated silver must be well washed in boiling water, and fused with some nitre; the use of which is to coagulate any cuprous particles which may adhere to the silver.

From the solution of copper in aquafortis, a blue pigment, called verditer, is obtained by precipitation with whiting. Notes to Chem. Ditt.

Concentrated Parting, also called Parting by Cementation, because it is actually performed by cementation, is used when the quantity of it is so great in proportion to the silver, that it cannot be separated by aquafortis. This operation is done in the following manner.

A cement is first prepared, composed of four parts of bricks powdered and sifted, of one part of green vitriol calcined till it becomes red, and of one part of common salt. The whole is very accurately mixed together, and a firm paste is made of it by moistening it with a little water or urine. This cement is called cement royal, because it is employed to purify gold, which is considered by chemists as the king of metals.

The gold to be cemented is to be reduced to plates as thin as small pieces of money. At the bottom of the crucible or cementing-pot, a stratum of cement, of the thickness of a finger, is to be put, which is to be covered with plates of gold; upon these another stratum of cement is to be laid, and then more plates of gold, till the crucible or pot is filled with these alternate strata of cement and of gold. The whole is then to be covered with a lid, which is to be luted with a mixture of clay and sand. This pot is to be placed in a furnace, or oven, and heated by degrees till it is moderately moderately red, which heat is to be continued during 24 hours. The heat must not be so great as to melt the gold. The pot or crucible is then left to cool, and the gold is to be carefully separated from the cement, and boiled at different times in a large quantity of pure water. This gold is to be effayed upon a touchstone or otherwise; and if it be found not sufficiently purified, it is to be cemented a second time in the same manner.

The vitriolic acid of the bricks and of the calcined vitriol disengages the acid of the common salt during this cementation: and this latter acid dissolves the silver alloyed with the gold, and separates it by that means.

This experiment proves, that although marine acid, while it is liquid, cannot attack silver, it is nevertheless a powerful solvent of that metal. But for this purpose it must be applied to the silver in the state of vapours, extremely concentrated, and assisted with a considerable heat. All these circumstances are united in the concentrated parting.

This experiment proves also, that notwithstanding all these circumstances, which favour the action of the marine acid, it is incapable of dissolving gold.

Lastly, the marine acid in this state more effectually dissolves the silver than the nitrous acid does in the parting by aquafortis, since this operation succeeds well when the silver is in so small a proportion as that it would be protected from the action of the nitrous acid in the ordinary parting.

Instead of sea-salt, nitre may be used with equal success; because the nitrous acid is then put in a state to attack the silver, notwithstanding the quantity of gold which covers it.

**Dry-Parting.** Dry-parting, or parting by fusion, is performed by sulphur, which has the property of uniting easily with silver, while it does not attack gold.

This method of separating these two metals would be the cheapest, the most expeditious and convenient of any, if the sulphur could dissolve the silver, and separate it from the gold as well and as easily as nitrous acid does: but, on the contrary, we are obliged to employ a particular treatment, and a kind of concentration, to begin the union of the sulphur alloyed with gold. Then repeated and troublesome fusions must be made, in each of which we are obliged to add different intermediate substances, and particularly the metals which have the strongest affinity with sulphur, to assist the precipitation, which in that case does not give a regulus of pure gold, but a gold still alloyed with much silver, and even with a part of the precipitating metals; so that, to complete the operation, cupellation is necessary, and also parting by aquafortis.

From what we have said concerning this operation, we may perceive, that it ought not to be made but when the quantity of silver with which the gold is alloyed is so great, that the quantity of gold which might be obtained by the ordinary parting is not sufficient to pay the expenses; and that it is only proper for concentrating a larger quantity of gold in a smaller quantity of silver. As this dry parting is troublesome, and even expensive, it ought not to be undertaken but on a considerable quantity of silver alloyed with gold. Accordingly Cramer, Schlutter, Schlieder, and all good chemists and artists who have given processes for the cry-parting, recommend its use only in the above-mentioned cases. We wish that this operation could be improved: it would be much more advantageous if it could be done by two or three fusions; and if by these an exact separation could be obtained of a small quantity of gold mixed with a large quantity of silver.

As this operation for extracting a small quantity of gold from a large quantity of silver is notwithstanding its inconveniences, approved by Schlutter, Scheffer, and other authors, and practised in Hartz, we shall add what Dr Lewis, in his excellent History of Gold, has said upon the subject.

The most advantageous method of separating a small portion of gold from a large one of silver, appears to be by means of sulphur, which unites with and scoriifies the silver without affecting the gold; but as sulphurated silver does not flow thin enough to suffer the small particles of gold diffused through it to reunite and settle at the bottom, some addition is necessary for collecting and carrying them down.

In order to the commixture with the sulphur, 50 or 60 pounds of the mixed metal, or as much as a large crucible will receive, are melted at once, and reduced into grains, by taking out the fluid matter, with a small crucible made red hot, and pouring it into cold water stirred with a rapid circular motion. From an eighth to a fifth of the granulated metal, according as it is richer or poorer in gold, is reserved, and the rest well mingled with an eighth of powdered sulphur. The grains enveloped with the sulphur are again put into the crucible, and the fire kept gentle for some time, that the silver, before it melts, may be thoroughly penetrated by the sulphur; if the fire was hastily urged, great part of the sulphur would be dissipated, without acting upon the metal.

If to sulphurated silver in fusion pure silver be added, the latter falls to the bottom, and forms there a distinct fluid not miscible with the other. The particles of gold, having no affinity with the sulphurated silver, join themselves to the pure silver, wherever they come in contact with it, and are thus transferred from the former into the latter, more or less perfectly according as the pure silver was more or less thoroughly diffused through the mixed. It is for this use that a part of the granulated metal was reserved. The sulphurated mass being brought into perfect fusion, and kept melted for near an hour in a close covered crucible, one-third of the reserved grains is thrown in; and as soon as this is melted, the whole is well stirred, that the fresh silver may be distributed through the mixed, to collect the gold from it. The stirring is performed with a wooden rod; an iron one would be corroded by the sulphur, so as to deprive the mixed of its due quantity of sulphur, and likewise render the subsequent purification of the silver more troublesome. The fusion being continued an hour longer, another third of the unfulphurated grains is added, and an hour after this the remainder; after which the fusion is further continued for some time, the matter being stirred at least every half hour from the beginning to the end, and the crucible kept closely covered in the intervals.

The sulphurated silver appears in fusion of a dark-brown colour; after it has been kept melted for a cer- tain time, a part of the sulphur having escaped from the top, the surface becomes white, and some bright drops of silver, about the size of peas, are perceived on it. When this happens, which is commonly in about three hours after the last addition of the referred grains, sooner or later according as the crucible has been more or less closely covered, and the matter more or less stirred, the fire must be immediately discontinued; for otherwise more and more of the silver, thus losing its sulphur, would subside and mingle with the part at the bottom in which the gold is collected.

The whole is poured out into an iron mortar greased and duly heated; or if the quantity is too large to be safely lifted at once, a part is first taken out from the top with a small crucible, and the rest poured into the mortar. The gold, diffused at first through the whole mass, is now found collected into a part of it at the bottom, amounting only to about as much as was reserved unfulphurated. This part may be separated from the fulphurated silver above it by a chisel and hammer; or more perfectly, the surface of the lower mass being generally rugged and unequal, by placing the whole mass with its bottom upwards in a crucible; the fulphurated part quickly melts, leaving unmelted that which contains the gold, which may thus be completely separated from the other. The fulphurated silver is effaced by keeping a portion of it in fusion in an open crucible till the sulphur is dissipated, and then dissolving it in aquafortis. If it should still be found to contain any gold, it is to be melted again; as much more unfulphurated silver is to be added as was employed in each of the former injections, and the fusion continued about an hour and a half.

The gold thus collected into a part of the silver may be further concentrated into a smaller part, by granulating the mass and repeating the whole process. The operation may be again and again repeated, till so much of the silver is separated, that the remainder may be parted by aquafortis without too much expense.

The foregoing process, according to Mr Schlutter, is practised at Rammelsberg in the Lower Harz. The prevailing metal in the ore of Rammelsberg is lead; the quantity of lead is at most 40 pounds on a quintal or 100 pounds of the ore. The lead worked off on a telf or concave hearth yields about 110 grains of silver, and the silver contains only a 384th part of gold; yet this little quantity of gold, amounting scarcely to a third of a grain in a hundred weight of this ore, is thus collected with profit. The author above-mentioned confines this method of separation to such silver as is poor in gold, and reckons parting with aquafortis more advantageous where the gold amounts to above a 64th of the silver; he advises also not to attempt concentrating the gold too far, as a portion of it will always be taken up again by the silver. Mr Scheffer, however, relates (in the Swedish Memoirs for the year 1752), that he has by this method brought the gold to perfect fineness; and that he has likewise collected all the gold which the silver contained; the silver of the last operations, which had taken up a portion of the gold, being referred to be worked over again with a fresh quantity of gold-bearing silver. The fulphurated silver is purified by continuing it in fusion for some time with a large surface exposed to the air; the sulphur gradually exhales, and leaves the silver entire.