or MERCURY, one of the metals, and so fusible that it cannot be reduced to a solid state but at a degree of cold, equal to 40 below 0 of Fahrenheit's thermometer. For the method of extracting quicksilver from its ore, &c. see ORES, Reduction of. For the various preparations, &c. see CHEMISTRY and Materia Medica Index; and for the natural history of the ores of quicksilver or mercury, see MINERALOGY Index.

Mines of quicksilver are very rare, insomuch that, according to the calculations of Hoffman, there is 50 times more gold got every year out of the mines than mercury and its ores. But Dr Lewis, in his notes upon Newmann, says, that Cramer supposes that Hoffman only meant five times instead of 50; but neither the Latin nor the English edition of this author expresses any such thought; on the contrary, he adopts the same opinion; and only adds, that mercury is much more frequently met with than is commonly believed; but being so volatile in the fire, it often flies off in the roasting of ores, and escapes the attention of metallurgists.

According to Newmann, the mines of Idria have produced at the rate of 231,778 pounds weight of mercury per annum; but those of Almaden in Spain produce much more. The chemists of Dijon inform us, that their annual produce is five or six thousand quintals, or between five and six hundred thousand pounds weight. In the year 1717 there were upwards of 2,500,000 pounds of quicksilver sent from them to Mexico, for the amalgamation of the gold and silver ores of that country.

At Guanacavelica in Brazil the annual produce of the mines, according to Bomare, amounts to one million of pounds, which are carried overland to Lima, thence to Africa, and lastly to Potosi for the same purpose.

Besides these mines there are others in Brazil near Villa Rica, where such a quantity of cinnabar, and native running mercury are found near the surface of the earth, that the black flaves often collect it in good quantities, and sell it for a trifling price to the apothecaries; but none of these mines have ever been worked or taken notice of by the owners. Gold naturally amalgamated with mercury is likewise met with in the neighbourhood of that place; and it is said that almost all the gold mines of that country are worked out by simply washing them out with running water, after reducing into powder the hard ores, which are sometimes imbedded in quartzose and rocky matrices.

In the duchy of Deux Ponts and in the Lower Austria the quicksilver flows from a chitofe or stony matrix, and is probably, says Mr Kirwan, mixed with some other metal, as its globules are not perfectly spherical. The mines of Friuli are all in similar beds or strata. The metal is likewise found visibly diffused through masses of clay or very heavy stone, of a white, red, or blue colour; of which last kind are the mines of Spain, some of Idria, and of Sicily. Malacagni found fluid quicksilver, as well as native cinnabar and mineral ethiops, near the lake of Travale in the duchy of Siena; but the quantity was so small as not to be worth the expense of working. On the other hand, the following mines afford profits to the owners after clearing all expenses, viz. those at Kremnitz in Hungary; at Horowitz in Bohemia; Zorge in Saxony; Wolfstien, Stahlberg, and Moeschfeld in the Palatinate. Mercury is also brought from Japan in the East Indies; but the greatest part of what is sold in Europe as Japan cinnabar is said to be manufactured in Holland.

Lemery, Pomel, and others, lay down some external marks by which those places are distinguished where there are mines of quicksilver, viz. thick vapours like clouds arising in the months of April and May; the plants being much larger and greener than in other places; the trees seldom bearing flowers or fruit, and putting forth their leaves more slowly than in other places; but, according to Neumann, these marks are far from being certain. They are not met with in all places where there is quicksilver, and are observed in places where there is none. Abundance of these cloudy exhalations are met with in the Hartz forest in Germany, though no mercury has ever been found there; to which we may add, that though vast quantities of mercurial ores are found at Almaden in Spain, none of the above-mentioned indications are there to be met with.

Native mercury was formerly sought from the mines of Idria with great avidity by the alchemists for the purpose of making gold; and others have showed as ridiculous an attachment to the Hungarian cinnabar, supposing it to be impregnated with gold; nay, we are informed by Neumann, that not only the cinnabar, antimony, and copper of Hungary, but even the vine trees of that country were thought to be impregnated with the precious metal. Not many years ago a French chemist advertised that he had obtained a considerable quantity of gold from the ashes of vine twigs and stems, as well as of the garden soil where they grew: but the falsehood of these assertions was demonstrated by the count de Lauragais to the satisfaction of the Royal Academy of Sciences.

The reduction of mercury into a solid state, so that Quicksilver it might be employed like silver, was another favourite alchemical pursuit. But all processes and operations of this kind, says Newmann, if they have mercury in them, are no other than hard amalgams. When melted lead or tin are just becoming consiftent after fusion, if a stick be thrust into the metal, and the hole filled with quicksilver, as soon as the whole is cold, the mercury is found solid. Macquer informs us, that mercury becomes easily solid by being exposed to the fumes of lead. Maurice Hoffman, as quoted by Newmann, even gives a process for reducing mercury, thus coagulated, to a state of malleability, viz. by repeatedly melting and quenching it in linseed oil. Thus, he tells us, we obtain a metal which can be formed into rings and other utensils. But here the mercury is entirely dissipated by the repeated fusions, and nothing but the original lead is left. Valerius, after mentioning strong soap-leys, or caustic lye, and some other liquors proper for fixing quicksilver, tells us, that by means of a certain gradatory water, the composition of which he learned from Creuling de Aurea Vellere, he could make a coagulum of mercury whenever he pleased, of such consistency that great part of it would resist cupellation; but what this gradatory water was, he has not thought proper to lay before the public.

**QUICK-MATCH,** among artillery men, a kind of combustible preparation formed of three cotton strands drawn into length, and dipped in a boiling composition of white-wine vinegar, saltpetre, and mealed powder. After this immersion it is taken out hot, and laid in a trough where some mealed powder, moistened with spirits of wine, is thoroughly incorporated into the twists of the cotton, by rolling it about therein. Thus prepared, they are taken out separately, and drawn through mealed powder; then hung upon a line and dried, by which they are fit for immediate service.

**QUID PRO QUO,** in Law, q. d. "what for what," denotes the giving one thing of value for another; or the mutual consideration and performance of both parties to a contract.

**QUID PRO QUO,** or **QUI PRO QUO,** is also used in physic to express a mistake in the physician's bill, where *quid* is wrote for *quo*, i.e., one thing for another; or of the apothecary in reading *quid* for *quo*, and giving the patient the wrong medicine. Hence the term is in the general extended to all blunders or mistakes committed in medicine, either in the prescription, the preparation, or application of remedies.

**QUIDDITY,** *quidditas,* a barbarous term used in the schools for *essence.* The name is derived hence, that it is by the essence of a thing that it is a *tale quid,* such a *quid,* or thing, and not another. Hence what is essential to a thing is said to be *quidditative.*

**QUIETISTS,** a religious sect, famous towards the close of the last century. They were so called from a kind of absolute rest and inaction, which they supposed the soul to be in when arrived at that state of perfection which they called the *unitive life,* in which state they imagined the soul wholly employed in contemplating its God, to whose influence it was entirely submissive; so that he could turn and drive it where and how he would. In this state, the soul no longer needs prayers, hymns, &c., being laid, as it were, in the bosom and between the arms of its God, in whom it is in a manner swallowed up.

Molinos, a Spanish priest, is the reputed author of *Quietism,* though the Illuminati in Spain had certainly taught something like it before. The sentiments of Molinos were contained in a book which he published at Rome in the year 1681, under the title of the *Spiritual Guide,* for which he was cast into prison in 1683, and where he publicly renounced the errors of which he was accused. This solemn recantation, however, was followed by a sentence of perpetual imprisonment, and he died in prison in the year 1696. Molinos had numerous disciples in Italy, Spain, France, and the Netherlands. One of the principal patrons and propagators of Quietism in France was Marie Bouvières de la Mothe Guyon, a woman of fashion, remarkable for goodness of heart and regularity of manners; but of an unsettled temper, and subject to be drawn away by the seduction of a warm and unbridled fancy. She derived all ideas of religion from the feelings of her own heart, and described its nature to others as she felt it herself. Accordingly her religious sentiments made a great noise in the year 1687; and they were declared unfounded, after accurate investigation, by several men of eminent piety and learning, and professedly confuted, in the year 1697, by the celebrated Boffuet. Hence arose a controversy of greater moment between the prelate last mentioned and Fenelon archbishop of Cambrai, who seemed disposed to favour the system of Guyon, and who in 1697 published a book containing several of her tenets. Fenelon's book, by means of Boffuet, was condemned in the year 1699, by Innocent XII. and the sentence of condemnation was read by Fenelon himself at Cambrai, who exhorted the people to respect and obey the papal decree. Notwithstanding this seeming acquiescence, the archbishop persisted to the end of his days in the sentiments, which, in obedience to the order of the pope, he retracted and condemned in a public manner.

A fact similar to this had appeared at Mount Athos in Thessaly, near the end of the 14th century, called *Helychaft,* meaning the same with Quietists. They were a branch of the mystics, or those more perfect monks, who, by long and intense contemplation, endeavoured to arrive at a tranquillity of mind free from every degree of tumult and perturbation. In conformity to an ancient opinion of their principal doctors (who thought there was a celestial light concealed in the deepest retirements of the mind), they used to sit every day, during a certain space of time, in a solitary corner, with their eyes eagerly and immovably fixed upon the middle regions of the belly, or navel; and boasted, that while they remained in this posture, they found, in effect, a divine light beaming forth from their soul, which diffused through their hearts inexpressible sensations of pleasure and delight. To such as inquired what kind of light this was, they replied, by way of illustration, that it was the glory of God, the same celestial radiance that surrounded Christ during his transfiguration on the Mount. Barlaam, a monk of Calabria, from whom the Barlaamites derived their denomination, styled the monks who adhered to this institution *Maggalians* and *Euchites,* and he gave them also the new name of *Umbilicani.* Gregory Palamas, archbishop of Thessalonica, defended their cause against Barlaam, who was condemned in a council held at Constantinople in the year 1341.—See Fenelon's Max. des Saints. The Mahometans seem to be no strangers to quietism. They expound a passage in the 17th chapter of the Koran, viz. "O thou foul which art at rest, return unto thy Lord, &c." of a foul which, having, by pursuing the concatenation of natural causes, raised itself to the knowledge of that being which produced them and exits of necessity, rests fully contented, and acquiesces in the knowledge, &c. of him, and in the contemplation of his perfection.