Madras patanæ, et Africance, à Jacobo Petivero ad opus Petiver consummandum collatæ, &c. Many of his small tracts Petrarch. having become scarce, his works were collected and published, exclusive of his papers in the Transactions, in 2 vols. folio, in the year 1764. PETIVERIA, a genus of plants belonging to the hexandria class, and in the natural method ranking under the 12th order, Holoracea. See BOTANY Index. PETRA, (Cæsar, Lucian), a town of Greece, on the coast of Illyricum, near Dyrrhachium, and not far from the mouth of the river Panyasus.-Another PETRA, (Livy); a town of Mædica, a district of Thrace, lying towards Macedonia; but in what part of Macedonia, he does not say. PETRA (Ptolemy), Petræa (Silius Italicus), Petrina (Italicus), in both which last urbs is understood; an inland town of Sicily, to the south-west of Engyum. Now Petraglia (Cluverius). PETRA Jecktael (2 Kings xiv.), a town of the Amalekites; near the Adscensus Scorpionis (Judges i.) and the valley of Salt in the south of Judea, afterwards in the possession of the Edomites, after destroying the A malekites. 20. 66 PETRA Recem, or Rekem, so called from Rekem king of the Midianites, slain by the Israelites (Num. xxxi.). Formerly called Arce, now Petra; the capital of Arabia Petræa (Josephus). Ptolemy places it in Long. 66. 45. from the Fortunate islands, and Lat. 30. It declines therefore 80 miles to the south of the parallel of Jerusalem, and 36 miles, more or less, from its meridian to the east. Josephus says, that the mountain on which Aaron died stood near Petra; which Strabo calls the capital of the Nabatæi; at the distance of three or four days journey from Jericho. This Petra seems to be the Sela of Isaiah xvi. 1. and xlii. 11. the Hebrew name of Petra, a rock" Though some imagine Petra to be no older than the time of the Macedonians. PETRARCH, FRANCIS, a celebrated Italian poet, was born at Arezzo in 1304, and was the son of Petrarco di Parenzo. He studied grammar, rhetoric, and philosophy, for four years at Carpentras; from whence he went to Montpelier, where he studied the law under John Andreas and Cino of Pistoia, and probably from the latter received a taste for Italian poetry. As Petrarch only studied the law out of complaisance to his father, who on his visiting him at Bologna had thrown in the fire all the Latin poets and orators except Virgil and Cicero ; he, at 22 years of age, hearing that his father and mother were dead of the plague at Avignon, returned to that city to settle his domestic affairs, and purchased a country house in a very solitary but agree able situation, called Vaucluse; where he first knew the beautiful Laura, with whom he fell in love, and whom he has immortalized in his poems. He at length travel led into France, the Netherlands, and Germany; and at his return to Avignon entered into the service of Pope John XXII. who employed him in several important affairs. Petrarch was in hopes of being raised to some Considerable post: but being disappointed, he applied himself entirely to poetry; in which he met with much applause, that in one and the same day he received letters from Rome and the chancellor of the university of Paris, by which they invited him to receive the poetic crown. By the advice of his friends, he preferred Rome to Paris, and received that crown from 6 the senate and people on the 8th of April 1341. "The Petrarch. ceremony of his coronation (says Gibbon) was perform- v ed in the Capitol, by his friend and patron the suprere magistrate of the republic. Twelve patrician youths were arrayed in scarlet; six representatives of the most illustrious families, in green robes, with garlands of flowers, accompanied the procession; in the midst of. the princes and nobles, the senator, count of Anguillara, a kinsman of the Colonna, assumed his throne; and at the voice of a herald Petrarch arose. After discoursing on a text of Virgil, and thrice repeating his vows for the prosperity of Rome, he knelt before the throne, and received from the senator a laurel crown, with a more precious declaration, This is the reward of merit.' The people shouted, Long life to the Capitol and the poet! A sonnet in praise of Rome was accepted as the effusion of genius and gratitude ; and after the whole procession had visited the Vatican, the profane wreath was suspended before the shrine of St Peter. In the act or diploma which was presented to Petrarch, the title and prerogatives of poet-laureat are revived in the Capitol after the lapse of 1300 years; and he receives the perpetual privilege of wearing, at. his choice, a crown of laurel, ivy, or myrtle; of assum ing the poetic habit; and of teaching, disputing, interpreting, and composing, in all places whatsoever, and on all subjects of literature. The grant was ratified by the authority of the senate and people; and the character of citizen was the recompense of his affection for the Roman name. They did him honour, but they did him justice. In the familiar society of Cicero and Livy, he had imbibed the ideas of an ancient patriot; and his ardent fancy kindled every idea to a sentiment, and every sentiment to a passion." His love of soli-. tude at length induced him to return to Vaucluse; but, after the death of the beautiful Laura, Provence. became insupportable to him, and he returned to Italy in 1352; when, being at Milan, Galeas Viceconti made him counsellor of state. Petrarch spent almost all the rest of his life in travelling to and from the different cities in Italy. He was archdeacon of Parma, and canon of Padua ; but never received the order of priesthood. All the princes and great men of his time gave him public marks of their esteem; and while he lived at Arcqua, three miles from Padua, the Florentines deputed Boccace to go to him with letters, hy which they invited him to Florence, and informed him, that they restored to him all the estate of which his father and mother had been deprived during the dissensions between the Guelphs and Gibelines. He died a few years after at Arcqua, in 1374. He wrote many works that have rendered his memory immortal; these have been printed in four volumes folio. His life has been written by several authors, Amongst these there was one by Mrs Susanna Dobson, in 2 volumes 8vo, collected and abridged from the French. In this work we have the following elegant and just character of Petrarch. "Few characters, perhaps, have set in a stronger light the advantages of well regulated dispositions than that of Petrarch, from the contrast we behold in one particular of his life, and the extreme misery he suffered from the indulgence of an affection, which, though noble and delightful when justly placed, becomes a reproach and a torment to its possessor when once directed Gg 2 Petrarch. rected to an improper object. For, let us not deceive ourselves or others; though (from the character of Laura) they are acquitted of all guilt in their personal intercourse, yet, as she was a married woman, it is not possible, on the principles of religion and morality, to clear them from that just censure which is due to every defection of the mind from those laws which are the foundation of order and peace in civil society, and which are stamped with the sacred mark of divine authority. "In this particular of his character, therefore, it is sincerely hoped that Petrarch will serve as a warning to those unhappy minds, who, partaking of the same feelings under the like circumstances, but not yet suffering his misery, may be led, by the contemplation of it, by a generous regard to the honour of human nature, and by a view to the approbation of that all-seeing Judge who penetrates the most secret recesses of the heart, to check every unhappy inclination in its birth, and destroy, while yet in their power, the seeds of those passions which may otherwise destroy them. "As to the cavils or censures of those who, incapa ble of tenderness themselves, can neither enjoy the view of it when presented in its most perfect form, nor pity its sufferings when, as in this work, they appear unhappily indulged beyond the bounds of judgment and tranquillity; to such minds I make no address, well convinced, that, as no callous heart can enjoy, neither will it ever be in danger of being misled, by the example of Petrarch in this tender but unfortunate circumstance of his character. "To susceptible and feeling minds alone Petrarch will be ever dear.. Such, while they regret his failings, and consider them as warnings to themselves, will love his virtues; and, touched by the glowing piety and heart-felt contrition which often impressed his soul, will ardently desire to partake with him in those pathetic and sublime reflections which are produced in grateful and affectionate hearts, on reviewing their own lives, and contemplating the works of God. "Petrarch had received from nature a very dangerous present. His figure was so distinguished as to attract universal admiration. He appears, in his portraits, with large and manly features, eyes full of fire, a blooming complexion, and a countenance that bespoke all the genius and fancy which shone forth in his works. In the flower of his youth, the beauty of his person was 30 very striking, that wherever he appeared, he was the object of attention. He possessed an understanding active and penetrating, a brilliant wit, and a fine imagination. His heart was candid and benevolent, susceptible of the most lively affections, and inspired with the noblest sentiments of liberty. "But his failings must not be concealed. His temper was, on some occasions, violent, and his passions headstrong and unruly. A warmth of constitution hurried him into irregularities, which were followed with repentance and remorse.-No essential reproach, however, could be cast on his manners, till after the 23d year of his age. The fear of God, the thoughts of death, the love of virtue, and those principles of religion which were inculcated by his mother, preserved him from the surrounding temptations of his earlier life." A resemblance has been traced, in several instances, * tion. between this admired poet and our late famous Yorick. Petrarcis Both, we know, had great wit and genius, and no D less imprudence and eccentricity; both were canons, or Petrifacprebendaries, the Italian of Padua, &c. and the Englishman of York; they both 66 ran over France, without any business there." If the bishop of Lombes patronised and corresponded with the one, a prelate of Dr Gilthe English church, now deceased, desired, in a letter, bert, Arch. to shandyiset with the other. In their attachments to York. Laura and Eliza, both married women, these two prebendaries were equally warm, and equally innocent. own exAnd, even after death, a most remarkable circumstance pression. has attended them both; some persons, we are told, stole Petrarch's bones, in order to sell them; and, in like manner, Yorick's body, it is confidently affirmed, was also stolen, and his skull has been exhibited at Oxford. PETRE, or Saltpetre. See NITRE, CHEMISTRY. and MINERALOGY Index. PETRIFACTION, in Natural History, denotes. the conversion of wood, bones, and other substances, principally animal or vegetable, into stone. These bodies are more or less altered from their original state, according to the different substances they have lain buried among in the earth; some of them having suffered very little change, and others being so highly impregnated with crystalline, sparry, pyritical, or other extraneous matter, as to appear mere masses of stone or lumps of the matter of the common pyrites; but they are generally of the external dimensions, and retain more or less of the internal figure, of the bodies into the pores of which this matter has made its way. The animal substances thus found petrified are chiefly seashells; the teeth, bony palates, and bones of fish; the bones of land animals, &c. These are found variously altered, by the insinuation of stony and mineral matter into their pores; and the substance of some of them is now wholly gone, there being only stony, sparry, or other mineral matter remaining in the shape and form. + His Grace's Respecting the manner in which petrifaction is accomplished, we know but little. It has been thought by many philosophers, that this was one of the rare processes of nature; and accordingly such places as afforded a view of it, have been looked upon as great curiosities. However, it is now discovered, that petrifaction is exceedingly common and that every kind of water carries in it some earthly particles, which being precipitated from it, become stone of a greater or lesser degree of hardness: and this quality is most remarkable in those waters which are much impregnated with selenitic matter. It has been found by observation, that iron contributes greatly to the process and this it may do by its precipitation of any aluminous earth which happens to be dissolved in the water by means of an acid; for iron has the property of precipitating this earth. Calcareous earth, however, by being soluble in water without any acid, must contribute very much to the process of petrifaction, as they are capable of a great degree of hardness by means only of being tion. tion. Petrifac joined with fixed air, on which depends the solidity of the size or of the shape; but it occasions, both at the Petrifaeour common cement or mortar used in building houses. surface and in the inside, a change of substance, and The name petrifaction belongs only, as we have seen, the ligneous texture is inverted; that is to say, that to bodies of vegetable or animal origin; and in order to which was pore in the natural wood, becomes solid in determine their class and genus, or even species, it is that which is petrified; and that which was solid or necessary that their texture, their primitive form, and full in the first state, becomes porous in the second. in some measure their organization, be still discernible. In this way, says M. Musard, petrified wood is much Thus we ought not to place the stony kernels, moulded less extended in pores than solid parts, and at the same in the cavity of some shell, or other organized body, in time forms a body much more dense and heavy than the rank of petrifactions, properly so called. the first. As the pores communicate from the circumference to the centre, the petrifaction ought to begin at the centre, and end with the circumference of the organic body subjected to the action of the lapidific fluids. Such is the origin of petrifactions. They are organized bodies which have undergone changes at the bottom of the sea or the surface of the earth, and which have been buried by various accidents at different depths under the ground. Petrifactions of the vegetable kingdom are almost all either gravelly or siliceous; and are found in gullies, trenches, &c. Those which strike fire with steel are principally found in sandy fissures; those which effervesce in acids are generally of animal origin, and are found in the horizontal beds of calcareous earth, and sometimes in beds of clay or gravel: in which case the nature of the petrifaction is different. As to the substances which are found in gypsum, they seldom undergo any alteration, either with respect to figure or composition, and they are very rare. Organized bodies, in a state of petrifaction, generally acquire a degree of solidity of which they were not possessed before they were buried in the earth, and some of them are often fully as hard as the stones or matrices in which they are enveloped. When the stones are broken, the fragments of petrifactions are easily found, and easily distinguished. There are some organized bodies, however, so changed by petrifaction, as to render it impossible to discover their origin. That there is a matter more or less agitated, and adapted for penetrating bodies, which crumbles and separates their parts, draws them along with it, and disperses them here and there in the fluid which surrounds them, is a fact of which nobody seems to entertain any doubt. Indeed we see almost every substance, whether solid or liquid, insensibly consume, diminish in bulk, and at last, in the lapse of time, vanish and disappear. A petrified substance, strictly speaking, is nothing more than the skeleton, or perhaps image, of a body which has once had life, either animal or vegetable, combined with some mineral. Thus petrified wood is not in that state wood alone. One part of the compound or mass of wood having been destroyed by local causes, has been compensated by earthy and sandy substances, diluted and extremely minute, which the waters surrounding them had deposited while they themselves evaporated. These earthy substances, being then moulded in the skeleton, will be more or less indurated, and will appear to have its figure, its structure, its size, in a word, the same general characters, the same specific attributes, and the same individual differences. Farther, in petrified wood, no vestige of ligneous matter appears to exist. We know that common wood is a body in which the volume of solid parts is greatly exeeeded by that of the pores. When wood is buried in eertain places, lapidific fluids, extremely divided and sometimes coloured, insinuate themselves into its pores and fill them up. These fluids are afterwards moulded, and condensed. The solid part of the wood is decomposed and reduced into powder, which is expelied without the mass by aqueous filtrations. In this 'manner, the places which were formerly occupied by the wood are now left empty in the form of pores. This operation of nature produces no apparent difference either of In order to understand properly the detail of the formation of petrified bodies, it is necessary to be well acquainted with all their constituent parts. Let us take wood for an example. Wood is partly solid and partly porous. The solid parts consist of a substance, hard, ligneous, and compact, which forms the support of the vegetable; the porous parts consist of vessels or interstices which run vertically and horizontally across the ligneous fibres, and which serve for conducting air, lympb, and other fluids. Among these vessels, the trachia which rise in spiral forms, and which contain only air, are easily distinguished. The cylindric vessels, some of which contain lymph, and others the succus proprius, are full only during the life of the vegetable. After its death they become vacant by the evaporation and absence of the fluids with which they were formerly filled. All these vessels, whether ascending or descending, unite with one another, and form great cavities in the wood and in the bark. According to Malpighi and Duhamel, the ligneous fibres. are themselves tubular, and afford a passage to certain liquors; in short, the wood and bark are interspersed with utriculi of different shapes and sizes. The augmentation of the trunk in thickness, according to Malpighi is accomplished by the annual addition of a new exterior covering of fibres and of trachiæ. Others think that a concentric layer of sap-wood is every year hardened, whilst a new one is forming from the bark. But it is on all sides agreed that the concentric layers of wood are distinct from one another, because at the point of contact betwixt any two of them, the new vessels, as well as new fibres, are more apparent and perceptible than they are in any other place. Having made these preliminary remarks on the structure of vegetables, we shall now proceed to give an abridged account of the manner in which M. Mongez explains their petrifaction. In proportion to the tenderness and bad quality of wood, it imbibes the greater quantity of water; therefore this sort will unquestionably petrify more easily: than that which is hard. It is thought that all the petrified wood so often found in Hungary has been origi nally soft, such as firs or poplars. Suppose a piece of wood buried in the earth; if it be very dry, it will suck up the moisture which surrounds it like a sponge. This moisture, by penetrating it, will dilate all the parts of which it is composed. The trachia, or air-vessels, will be tion We have then, says M. Mongez, four distinct epochs in the process by which nature converts a piece of wood into stone, or, to speak more justly, by which she substitutes a stony deposit in its place: 1. Perfect vegetable wood, that is to say, wood composed of solid and of empty parts, ligneous fibres, and of vessels. 2. Wood having its vessels obstructed and choked up by an carthy deposit, while its solid parts remain unaltered. 3. The solid parts attacked and decomposed, forming new cavities betwixt the stony cylinder, which remain in the same state, and which support the whole mass. 4. These new cavities filled with new deposits, which incorporate with the cylinders, and compose nothing else but one general earthy mass representing exactly the piece of wood. tion Perifac be filled first, and then the lymphatic vessels and those fluid from this reaction a colour arises which stains Petriferwhich contain the succus proprius, as they are likewise more or less the new deposit; and this colour will make empty. The water which forms this moisture keeps in it easily distinguishable from that which has been laid in dissolution a greater or a less quantity of earth; and the inside of the vessels. In all petrified wood this this earth, detached, and carried along in its course, is shade is generally perceptible. reduced to such an attenuated state, that it escapes our eyes and keeps itself suspended, whether by the medium of fixed air or by the motion of the water. Such is the lapidific fluid. Upon evaporation, or the departure of the menstruum, this earth, sand, or metal, again appears in the form of precipitate or sediment in the cavi.. ties of the vessels, which by degrees are filled with it. This earth is there moulded with exactness: The lapse of time, the simultaneous and partial attraction of the particles, makes them adhere to one another; the lateral suction of the surrounding fibres, the obstruction of the moulds, and the hardening of the moulded earth, become general; and there consists nothing but an earthy substance which prevents the sinking of the neighbour ing parts. If the deposit is formed of a matter in general pretty pure, it preserves a whiter and clearer colour than the rest of the wood; and as the concentric layers are only perceptible and distinct in the wood, because the vessels are there more apparent on account of their size, the little earthy cylinders, in the state of petrified wood, must be there a little larger, and consequently must represent exactly the turnings and separations of these layers. At the place of the utriculi, globules are observed, of which the shapes are as various as the moulds wherein they are formed. The anastomoses of the proper and lymphatic vessels, form besides points of support or reunion for this stony substance. With regard to holes formed by worms in any bits of Let any one represent to himself this collection of Among the petrifactions of vegetables called dendrolites, are found part of shrubs, stems, roots, portions of the trunk, some fruits, &c. We must not, however, confound the impressions of mosses, ferns, and leaves, or incrustations, with petrifactions. Among the petrifactions of animals, we find shells, crustaceous animals, polyparii, some worms, the bony parts of fishes and of amphibious animals, few or no real insects, rarely birds and quadrupeds, together with the bony portions of the human body. The cornu ammonis are petrified shell-fish; and with regard to figured and accidental bodies, these are lusus naturæ. In order, says M. Bertrand, in his Dictionnaire des Fossiles, that a body should become petrified, it is necessary that it be, 1. Capable of preservation under ground: 2. That it be sheltered from the air and running water (the ruins of Herculaneum prove that bodies which have no connection with free air, preserve themselves untouched and entire). 3. That it be secured from corrosive exhalations. 4. That it be in a place where there are vapours or liquids, loaded either with metallic or stony particles in a state of dissolution, and which, without destroying the body, penetrate it, impregnate it, and unite with it in proportion as its parts are dissipated by evaporation. It is a question of great importance among naturalists, to know the time which Nature employs in petrifying bodies of an ordinary size. It was the wish of the emperor, duke of Lorraine, that some means should be taken for determining this question. M. le Chevalier de Baillu, director of the cabinet of natural history of his imperial majesty, and some other naturalists, had, several years ago, the idea of making a research which might throw some light upon it. His imperial majesty being informed by the unanimous observations of modern historians and geographers, that certain pillars which are actually seen in the Danube in Servia, near Belgrade, are remains of the bridge which Trajan constructed over that river, presumed that these pillars having been preserved for so many ages behoved to be petrified, and that they would furnish some information with regard to the time which nature employs in changing wood into stone. The emperor thinking this hope well founded, and wishing to satisfy his curiosity, ordered his ambassador at the court of Constantinople to tion. tion. Petrific to ask permission to take up from the Danube one of by the name of Mineralia Larvata, and defines them Fetrifecthe pillars of Trajan's bridge. The petition was grant to be "mineral bodies in the form of animals or vegeed, and one of the pillars was accordingly taken up; tables." The most remarkable observations concerning from which it appeared that the petrifaction had only them, according to Mr Kirwan, who differs in some advanced three fourths of an inch in the space of 1500 particulars from Mongez, are as follow. 1. Those of years. There are, however, certain waters in which shells are found on or near the surface of the earth; this transmutation is more readily accomplished.-Pe- those of fish deeper; and those of wood deeper still. trifactions appear to be formed more slowly in earths Shells in substance are found in vast quantities, and at that are porous and in a slight degree moist than in wa- considerable depths. 2. The substances most suscepter itself. tible of petrifaction are those which most resist the putrefactive process; of which kind are shells, the harder kinds of wood, &c.; while the softer parts of animals,. which easily putrefy, are seldom met with in a petrified state. 3. They are most commonly found in strata of marl, chalk, limestone, or clay: seldom in sandstone, still more seldom in gypsum; and never in gneiss, granite, basaltes, or schoerl. Sometimes they are found in pyrites, and ores of iron, copper, and silver; consisting almost always of that kind of earth or other mineral which surrounds them; sometimes of silex, agate, or cornelian. 4. They are found in climates where the animals themselves could not have existed. 5. Those found in slate or clay are compressed and flattened. The different species of petrifactions, according to Cronstedt, are, When the foundations of the city of Quebec in Canada were dug up, a petrified savage was found among the last beds to which they proceeded. Although there was no idea of the time at which this man had been buried under the ruins, it is however true, that his quiver and arrows were still well preserved. In digging a leadmine in Derbyshire, in 1744, a human skeleton was found among stags horns. It is impossible to say how many ages this carcase had lain there. In 1695 the entire skeleton of an elephant was dug up near Tonna in Thuringia. Some time before this epoch the petrified skeleton of a crocodile was found in the mines of that country. We might cite another fact equally curious which happened at the beginning of the last century. John Munte, curate of Slægarp in Scania, and several of his parishioners, wishing to procure turf from a drained marshy soil, found, some feet below ground an entire cart with the skeletons of the horses and carter. It is presumed that there had formerly been a lake in that place, and that the carter attempting to pass over on the ice, had by that means probably perished. In fine, wood partly fossil and partly coaly, has been found at a great depth, in the clay of which tile was made for the abbey of Fontenay. It is but very lately that fossil wood was discovered at the depth of 75 feet in a well betwixt Issi and Vauvres near Paris. This wood was in sand betwixt a bed of clay and pyrites, and water was found four feet lower than the pyrites. M. de Laumont, inspector general of the mines, says (Journal de Physique, Mai 1736), that in the leadmine at Pontpéan near Rennes, is a fissure, perhaps the only one of its kind. In that fissure, sea-shells, rounded pebbles, and an entire beech, have been found 240 feet deep. This beech was laid horizontally in the direction of the fissure. Its bark was converted into pyrites, the sap-wood into jet, and the centre into coal. A great many pieces of petrified wood are found in different counties of France and Savoy. In Cobourg in Saxony, and in the mountains of Misnia, trees of a considerable thickness have been taken from the earth, which were entirely changed into a very fine agate, as also their branches and their roots. In sawing them, the annual circles of their growth have been distinguished. Pieces have been taken up, on which it was distinctly seen that they had been gnawed by worms; others bear visible marks of the hatchet. In fine, pieces have been found which were petrified at one end, while the other still remained in the state of wood fit for being burned. It appears then that petrified wood is a great deal less rare in nature than is commonly imagined. Cronstedt has excluded petrifactions from any place in the body of his system of mineralogy, but takes notice of them in his appendix. He distinguishes them. 54 I. Terræ Larvatæ; extraneous bodies changed into a limy substance, or calcareous changes. These are, 1. Loose or friable. 2. Indurated. The former are of a chalky nature in form of vegetables or animals; the second filled with solid limestone in the same forms. Some are found entirely changed into a calcareous spar. All of them are found in France, Sweden, and other countries in great plenty. On these petrifications Cronstedt observes, that shells and corals are composed of limy matter even when still inhabited by their animals, but they are classed among the petrifactions as soon as the calcareous particles have obtained a new arrangement; for example, when they have become sparry; filled with calcareous earth either hardened or loose, or when they lie in the strata of the earth. "These, says he, form the greatest part of the fossil collections which are so industriously made, often without any regard to the principal and only use they can be of, viz. that of enriching zoology. Mineralogists are satisfied with seeing the possibility of the changes the limestone undergoes in regard to its particles; and also with receiving some insight into the alteration with the earth has been subject to from the state of the strata which are now found in it." The calcined shells, where the petrifactions are of a limy or chalky nature, answer extremely well as a manure; but the indurated kind serve only for making grottoes. Gypseous petrifactions are extremely rare; however, Chardin informs us that he had seen a lizard inclosed in a stone of that kind in Persia. II. Larvæ, or bodies changed into a flinty substance. III. Larva Argillacea; where the bodies appear to |