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many, and, in 1688, carne to Utrecht, where he by refusing to admit Andrew Popham, a Romas received an invitation from the prince and prin- Catholic, as a pensioner of the Chaner-House, cass of Orange (to whom their party in England though the man came with a letter from kinz had recommended him) to come to the Hague. James himself to the governors. In 1680 be Here he was at once made acquainted with the published his Telluris Theoria Sacra, so univercounsels of the prince, and advised the fitting sally admired for the purity of the style and out of a feet in Holland to support his desizas. beauty of the sentiments, that king Charles gare This, and the Account of his Travels, which, encouragement to a translation of it into Englisa: with some papers, in single sheets, reflecting on and though, in point of philosophy, it is conthe proceedings of England, were industriously pletely exploded, the book will ever continue to dispersed throughout the country, alarmed king charm the reader by the eloquence of its style, James, and occasioned him twice to insist, by and the grandeur of its imagery. It was anhis ambassador, on his being dismissed. This, swered by Warren, heill, and Whiston; to all of after much importunity, was done, though he whom Dr. Burnet replied. After the Revolucontinued to be trusted and employed as before. tion he was made clerk of the closet to the kin: To put an end to his frequent conferences with of which place he was deprived in 1692, for pubthe Dutch ministers, a prosecution for high trea- lishing some dangerous positions in his Archæoson was set on foot against him both in England logia Philosophicæ. He died in 1915. Since and Scotland. But Burnet receiving the news his death have been published, his books, De before it arrived at the States, he avoided the Statu Vortuorum et Resurgentium, and De Fide storm, by petitioning for, and obtaining, a bill of et Ofñciis Christianorum. naturalisation, in order to an intended marriage BCRNETT (James), lord Monboddo. a with Mary Scot, a Dutch lady of considerable learned lawyer and polite writer, was born at the fortune. After his marriage, being legally under family-seat of Monboddo, in North Britain, in the protection of Holland, when he found king '1714. He was educated at Laurepcekirk, AberJames plainly subverting the constitution, he deen, and Groningen, where he studied the civil omitted no method to promote the design the law. In 1738, on his return to Scotland, he was prince of Orange had formed of delivering Great admitted an advocate, and obtained considerable Britain, and came over with him in quality of practice. On the death of his relation, lord chaplain. He was soon advanced to the see of ton, in 1767, he was promoted, by the title of Salisbury, and declared for moderate measures lord Monboddo, to the bench; and died at Edinwith regard to the clergy, who scrupled to take burgh of a paralytic stroke, in 1799. His lordthe oaths, as well as for the toleration of non- ship was deeply read in Greek literature, his love conformists. His Pastoral Letter, concerning of which induced him to despise more modern the oaths of allegiance and supremacy to kiny learning. He indulged in some curious specuWilliam and queen Mary, 1689, happening to lations; seriously advocating the existence of touch upon the right of conquest, gave such satyrs and mermaids, together with a supposed offence to both houses of parliament, that it was affinity between the human and the monkey ordered to be burnt by the hands of the common tribes. His Origin and Progress of Language executioner. In 1698 he lost his wife by the appeared in 1773; and the First Part of his Ansmall-pox; and, as he was almost immediately cient Metaphysics in 1778. This last extended after appointed preceptor to the duke of Glouto six volumes. cester, of whose education he took great care, BURNEY (Charles, Mus. D.), was a native this employment, and the tender age of his chil- of Shrewsbury, and born in 1726. Having redren, induced him the same year to supply her ceived the rudiments of education, first at the loss by a marriage with Mrs. Berkley, eldest grammar-school of his native town, and at Chesdaughter of Sir Richard Blake, knight. In ter, he returned home in 1741, and continued 1699 he published his Exposition of the thirty- the study of music, for which he had early shown nine articles; which occasioned a representation a strong taste. He was finally placed under Dr. against him in the lower house of convocation, Arne for three years, and in 1749 was elected 1701; but he was vindicated in the upper house. organist to a church in Fenchurch-strect. His His speech in the house of lords in 1704, against stay in London, however, was short; after comthe bill to prevent occasional conformity, was posing, in the winter of 1749, Robin Hood, Alseverely attacked. He died in 1715, and was fred, and Queen Mab, for Drury-lane, he retired interred in the church of St. James, Clerkenwell, to Lynn Regis, where he commenced his great where he has a monument. He formed a scheme undertaking, the General History of Music, the for augmenting the poor livings; which he first volume of which appeared in 1776, and the pressed forward with such success, that it ended remaining three at intervals, till the whole was in an act of parliament passed in the second year completed, in 1789. He returned, after nine of queen Anne, for the augmentation of the years' absence, to the metropolis, and produced livings of the poor clergy.

at Drury-lane an English version of the Devin BURNET (Thomas), a learned writer in the end du Village of Rousseau. In 1769 he took an of the seventeenth century, was born at Croft, in honorary degree of doctor of music at Oxford, Yorkshire, in 1635, and educated at Cambridge where his probationary exercise was much adunder the tuition of Mr. Tillotson, afterwards mired, and frequently performed. The year folarchbishop of Canterbury. In the beginning of lowing he went abroad, and on his return pub1685 he was made master of the Charter-Hlouse, lished his Musical Tour through France and after which he entered into holy orders. The Italy. In 1772 he again left England and made year following he distinguished himself greatly, a tour through Germany and the Netherlands, an

account of which appeared in two volumes, oc- nations in the East and West Indies. The antitavo. On his second return he became a fellow quity of this custom rises as high as the Theban of the Royal Society, and drew up for the Philo- war, where we are told of the solemnity accoinsophical Transactions, An Account of Little panying this ceremony at the pyre of Meuæceus Crotch the Infant Musician, the present Oxford and Archemorus, who were contemporary with musical professor. His other works are- An Jair, the eighth judge of Israel. Homer abounds Account of the Commemoration of Handel in with descriptions of such funeral obsequies. In 1785, with a Memoir of that celebrated man; a the inland regions of Asia, the practice was of Life of Metastasio, in 3 vols. 8vo. 1796; an very ancient date, and the continuance long : for Essay on the History of Comets; a Plan of a we are told, that, in the reign of Julian, the king Public Music School; and The Cunning Man; of Chionia burnt his son's body, and deposited besides numerous sonatas, duets, and concertos. the ashes in a silver urn. Coeval almost with Dr. Burney was for some time an inhabitant of the first instances of this kind in the East, was a house in St. Martin's-street, near Leicester- the practice in the western parts of the world. square, which was once the habitation of Sir The Herulians, the Getes, and the Thracians, Isaac Newton; but the last twenty-five years of had all along observed it; and its antiquity was his life were spent in his apartments in Chelsea as great with the Celtæ, Sarmatians, and other College, to which he was organist. Several of neighbouring nations. The origin of this custom his children, of whom he had eight, by two mar- seems to have been friendship to the deceased : riages, have also distinguished themselves in the their ashes were preserved, as we preserve a lock literary world, especially his second son, and of hair, a ring, or a seal, which had belonged to madame d'Arblay, authoress of Evelina, &c. a deceased friend. Kings were burnt in cloth His eldest son James was a companion of cap- made of the asbestos, that their ashes might be tain Cook round the world. Dr. Burney died preserved pure from any mixture with the fuel in 1814, aged eighty-eight.

and other matters thrown on the funeral pile. BURNEY (Charles, D.D.), was the second son The same method is still observed with the princes of the preceding, and born at Lynn, in Norfolk, of Tartary. Among the Greeks, the body was in 1757. He was educated at the Charter-house, placed on the top of a pile, on which were thrown and Caius College, Cambridge, whence he re- divers animals, and even slaves and captives, moved to king's College, Aberdeen, where he besides unguents and perfumes. In Homer's took his master's degree, in 1781. Soon after account of the funeral of Patroclus we find a we find him an assistant in an academy at High- number of sheep and oxen thrown in; then horses gate; and then, at Chiswick, in that of Dr. Rose. followed by two dogs, and lastly by twelve Trojan While here he wrote some criticisms in the prisoners. The same customs are mentioned by Monthly Review, conducted in this neighbour- Virgil in the funeral of his Trojans; where, behood, particularly on the Monostrophies of Mr. sides oxen, swine, and all manner of cattle, we Huntingford. About this time he married the find eight youths condemned to the flames. The daughter of Dr. Rose, and opened a school at body was covered with the fat of the beasts, that Hammersmith, in 1786; from whence, in 1793, it might consume the sooner; it being reckoned he removed to Greenwich. In 1792 he had ob- great felicity to be quickly reduced to ashes. We tained the degree of doctor of laws from Aber- are assured by Plutarch and Macrobius, that with deen and Glasgow. Late in life he took orders, every ten men it was customary to put in one on which occasion he was presented to the living woman. Soldiers usually had their arms burnt of St. Paul, Deptford, the rectory of Cliffe, a with them. The garments worn by the living prebend in Lincoln cathedral, the honorary de- were also thrown on the pile, with other ornagree of D. D. and made chaplain in ordinary to ments and presents; a piece of extravagance the king. He died, December the 28th, 1817. which the Athenians carried to so great a height, His library was purchased by parliament, and that some of the law-givers restrained them, by presented to the British Museum. His works severe penalties, from defrauding the living by are-1. Appendix ad Lexicon Græco-Latinum a their liberality to the dead. In some cases, burnJoan. Scapulam, 1789. 2. Remarks on the ing was expressly forbidden among the Romans, Greek Verses of Milton, 1791. 3. Richardi and even looked upon as the highest impicty. Bentleii et Doctorum Virorum Epistolæ, 4to. Thus infants, who died before the breeding of 1807. 4. Tentamen de Metris ab' Æschylo in teeth, were intombed unburnt in the ground, in a Opericis Cantibus Adhibitis, 8vo. 1809. 5. particular place set apart for this purpose, called Bishop Pearson's Exposition of the Creed, suggrundarium. The same was practised with abridged, 12mo. 6. Philemonis Lexicon Græcè, regard to those struck dead by lightning. Some 4to. 7. A Sermon at the Anniversary of the say that burning was denied to suicides. The Sons of the Clergy at St. Paul's, 4to. 1813. manner of burning among the Romans was not

BURNING, considered philosophically, is the unlike that of the Greeks; the corpse, being action of fire on some pabulum or fuel, by which taken without the city, was carried directly to the minute parts thereof are put into a violent the place appointed; which, if it joined to the motion, and some of them, assuming the nature sepulchre, was called bustum; if separate from of fire themselves, fly off in orbem, while the it, ustrina; and there laid on the rogus or pyra, rest are dissipated in form of vapor, or reduced a pile of wood prepared on which to burn it, to ashes.

built in shape of an altar, but of different height BURNING, in antiquity, was a method of dis- according to the quality of the deceased. Round posing of the dead, much practised by the ancient the pile they set cypress trees, probably to hinder Greeks and Romans, and still retained by several the noisome smell of the corpse. The body was not placed on the bare pile, but on the couch or ing use of a burning glass which he had hitherto bed whereon it lay. This done, the next of blood used in kindling his fire; for', says he, 'should, performed the ceremony of lighting the pile; they bring a writ against me, I shall immediately which they did with a torch, turning their faces place my glass in the sun at some little distance all the while the other way, as if it were done from it, and set it on fire.' Pliny and Lactantius with reluctance. During the ceremony, decur- have also spoken of glasses that burn by refracsions and games were celebrated ; after which tion. The foriner calls them balls or globes of came the ossilegium, or gathering of the bones glass or crystal, which exposed to the sun, transand ashes; also washing and anointing them, and mit a heat sufficient to set fire to cloth, or corrode repositing them in urns.

the dead flesh of those patients who stand in need "Burning, in medicine and surgery, denotes of caustics; and the latter, after Clemens Alex the application of an actual cautery See Cau- andrinus, takes notice that fire may be kindled TERY.

by interposing glasses filled with water betweer BURNING, or BRENNING, in our old writings, the sun and the object, so as to transmit the rays denotes an infectious disease, got in the stews by to it. It seems difficult to conceive how they conversing with lewd women, and supposed to should know such glasses would burn without be the same with what we now call the venereal knowing they would magnify, which it is granted disease.

they did not, till towards the close of the thirBURNING ALIVE, among the Romans, was a teenth century. M. de la Hire accounts for this, punishment inflicted on deserters, betrayers of the by observing, that their burning glasses being public councils, incendiaries, and even Christians: spheres, either solid or full of water, their foci It was called crematio. The Jews had two ways would be one-fourth of their diameter distant of burning; the one called burning of the body, from them. If then their diameter were supposed performed with wood and faggots; the other half a foot, which is the most we can allow, an burning of the soul, combustio animæ, performed object must be only at an inch and a half distance by pouring scalding hot lead down their throats. to perceive it magnified; those at greater distances Incest in the ascending and descending degrees do not appear greater, but only more confused was thus punished by them. But philanthropy through the glass than out of it. Among the is shocked to reflect, for what trifling crimes this ancients, the burning mirrors of Archimedes and horrid punishment has been inflicted among other Proclus are famous. By the latter the navy of nations. Even in our own country, till within Vitellius besieging Byzantium, according to Zothese few years, burning alive was the punish- naras, was burnt to ashes. Among the moderns, ment of women, convicted of coining or counter- the most remarkable burning mirrors are those of feiting shillings! Thus was the weaker sex pu- Settala, Vilette, Tschirnhausen, Buffon, Trudaine, nished in the most barbarous manner, for a and Parker. Settala, canon of Padua, made a trifling felony, which could hardly wrong any parabolic mirror, which, according to Schottus, individual above the value of a few pence. burnt pieces of wood at the distance of fifteen or

BURNING INTERNAL. See COMBUSTION. sixteen paces. The following experiments are

BURNING GLASSES are commonly made convex noled in the Acta Eruditoruin. 1. Green wood and spherical. The small space upon which the takes fire instantaneously, so as a strong wind collected rays fall, is called the focus; where cannot extinguish it. 2. Water boils imme wood, or any other combustible matter being put, diately; and eggs in it are presently edible. 3. A will be set on fire. The term burning glass is mixture of tin and lead, three inches thick, drops also applied to those concave mirrors, whether presently; and iron and steel plate becomes redcomposed of glass quick-silvered, or of metalline hot presently, and a little after burns into holes. matters, which burn by reflection, condensing the 4. Things not capable of melting, as stones, bricks. sun's rays into a focus similar to the former. The &c. become soon red-hot, like iron. 5. Slate beuse of burning glasses appears to have been very comes first white, then a black glass. 6. Tiles ancient. Diodorus Siculus, Lucian, Dion, Zo- are converted into a yellow glass : and shells naras, Galen, Anthenius, Eustathius, Tzetzes, into a blackish yellow one. 7. A pumice stone, and others, attest, that by means of them Archi- emitted from a volcano, melts into white glass. medes set fire to the Roman fleet at the siege of 8. A piece of crucible also vitrifies in eight miSyracuse. Tzetzes is so particular in his account nutes. 9. Bones are soon turned into an opaque of this matter, that his description suggested to glass, and earth into a black one. The breadta Kircher the method by which it was probably of this mirror is near three Leipsic ells, its focus accoinplished. According to that author, Ar- two ells from it; it is made of copper, and its chimedes set fire to Marcellus's navy, by means substance is not above double the thickness of of a burning glass composed of small square the back of a knife. Villette, a French artist of mirrors, moving every way upon hinges; which, Lyons, made a large mirror, which was bought when placed in the sun's rays, directed them by Tavernier, and presented to the king of Perupon the Roman fleet, so as to reduce it to ashes sia; a second, bought by the king of Denmark; at the distance of a bow-shot. That the ancients a third, presented by the French king to the Royal were also acquainted with the use of catoptric or Academy; a fourth, has been in England, where refracting burning glasses, appears from a passage it was publicly exposed. The effects hereof, as in Aristophanes's comedy of the Clouds, which found by Dr. Harris, and Dr. Desaguliers, are, clearly treats of their effects. The author intro- that a silver sixpence is melted in seven second duces Socrates as examining Strepsiades about and a half, a halfpenny in sixteen, and runs w the method he had discovered of getting clear of a hole in thirty-four. Tin melts in three secon his debts. He replies, that he thought of mak- cast iron in sixteen, slate in three; a fossil she

a fossil shell

calcines in seven seconds; a piece of Pompey's flat sides of the plates or leaves, of which it is pillar at Alexandria vitrifies, the black part in composed, were presented to the glass, did not fifty seconds, the white in fifty-four; copper ore show the least disposition to melt; but, on prein eight seconds; bone calcines in four seconds, senting a transverse section of it, or the edges of vitrifies in thirty-three. An emerald melts into the plates, it melted in an instant, with a hissing a substance like a turquois stone; a diamond noise, into a brownish yellow matter. Calcareous weighing four grains loses seven-eighths of its stones did not completely melt: but there was weight; the asbestos vitrifies; as all other bodies detached from them a circle more compact than will do, if kept long enough in the focus; but the rest of the mass, and of the size of the focus ; when once vitrified, the mirror can go no farther the separation of which seemed to be occasioned with them. This mirror is forty-seven inches by the shrinking of the matter which had begun wide, and is ground to a sphere of seventy-six to enter into fusion. The white calx of antimony, inches radius; so that its focus is about thirty- commonly called diaphoretic antimony, melted eight inches from the vertex. · Its substance is a better than the calcareous stones, and changed composition of tin, copper, and tin glass. Every into an opaque pretty glossy-substance, like white lens, whether convex, plano-convex, or convexo- enamel. It was observed, that the whiteness of convex, collects the sun's rays, dispersed over its the calcareous stones and the antimonial calx was convexity, into a point by refraction: and is of great disadvantage to their fusion, by reason of therefore a burning glass. The most consider- their reflecting great part of the sun's rays; so able of this kind is that made by M. de Tchirn- that the subject could not undergo the full actihausen : the diameters of his lenses are three and vity of the heat thrown upon it by the burning four feet, the focus at the distance of twelve feet, glass. The case was the same with metallic boand its diameter an inch and a half. To make dies, which melted so much the more difficultly the focus the more vivid, it is collected a second as they were more white and polished; and this time by a second lens parallel to the first, and difference was so remarkable, that in the focus of placed in that point where the diameter of the this mirror, so fusible a metal as silver, when its cone of rays formed by the first lens is equal to surface was polished, did not melt at all. M. the diameter of the second ; so that it receives Trudaine, a French gentleman, constructed a them all; and the focus, from an inch and a half, burning lens on a new principle. It was comis contracted into the space of eight lines, and its posed of two circular segments of glass spheres, force increased proportionably. “This glass vitri- each four feet in diameter, applied with their fies tiles, slates, pumice-stones, &c. in a moment. concave sides towards each other. The caIt melts sulphur, pitch, and all resins, under vity was filled with spirit of wine, of which it water; the ashes of vegetables, woods, and other contained forty pints. It was presented by the matters, are transmuted into glass; and every maker to the Royal Academy of Sciences, but was, thing applied to its focus is either melted, turned .not long after, broken by accident. The expense into a calx, or into smoke. Tschirnhausen ob- of constructing it amounted to about £1000 serves, that it succeeds best when the substance sterling, and after all, it does not appear that the applied is laid on a hard charcoal well burnt. effects of this lens were very great. Mr. MagelSir Isaac Newton presented a burning glass to lan informs us, that it could only coagulate the the Royal Society, consisting of seven concave particles of platina in twenty minutes, while Mr. glasses, so placed, as that all their foci join in one Parker's lens entirely melted them in less than physical point. Each glass is about eleven inches two, and a half in diameter,: six of them are placed M. Buffon's burning mirror, which he supround the seventh, to which they are all conti- poses to be of the same nature with that of Arguous; and they form a kind of segment of a chimedes, consists of a number of small mirrors sphere, whose subtense is about thirty-four inches of glass quicksilvered, all of which are held togeand a half, and the central glass lies about an ther by an iron frame. Each of these small inch farther in than the rest. The common focus mirrors is also movable by a contrivance on the is about twenty-two inches and a half distant, and back part of the frame, that so their reflections about an inch in diameter. This glass vitrifies may all coincide in one point. By this means brick or tile in one second, and melts gold in they are capable of being accommodated to vathirty. It appears that glass quicksilvered is a rious heights of the sun, and to different distances. more proper material for burning glasses than The adjusting them in this manner takes up a metals ; for the effects of that speculum where- considerable time; but after they are so adjusted , with Mr. Macquer melted the platina, seem to the focus will continue unaltered for an hour or have been superior to those above mentioned, more. In 1747 he constructed a machine of this though the mirror itself was much smaller. The kind, with 140 plane mirrors; each about four diameter of this glass was only twenty-two inches, inches long, and three broad; these were fixed and its focal distance twenty-eight. Black flint, about a quarter of an inch distant from each when exposed to the focus, being powdered to other, upon a large wooden frame, of about six prevent its crackling and flying about, and se- feet square. The experiment was first tried with cured in a large piece of charcoal, bubbled up twenty-four mirrors, which readily set on fire a and ran into transparent glass in less than half a combustible matter, prepared of pitch and tow, minute. Hessian crucibles, and glass-house pots, and laid on a deal board, at the distance of sixtyvitrified completely in three or four seconds. six French feet. He then put together a kind of Forged iron smoked, boiled, and changed into a polyhedron, consisting of 168 pieces of plane vitrescent scoria as soon as it was exposed to the looking glass, each being six inches square; and focus. The gypsum of Montmartre, when the by means of this some boards of beech were set

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on fire, at the distance of 150 feet, in the month, within a chaced mortice in which it moves, an of March, and a silver plate was melted at the, apparatus H, with the iron plate, I, fixed thereto; distance of sixty feet. This machine, besides and this part turning on a ball and socket, K;a other advantages, may be easily moved, so as to method is thereby obtained of placing the matter burn downwards or horizontally; and it burns under experiment, so as to be acted upon by the either in its distant focus, or in any nearer in- focal rays in the most direct and powerful man. terval, which our common burning glasses cannot ner. LL, a strong mahogany frame, moving on do, because their focus is wholly fixed. This castors, MM. Immediately under the table N, machine, in the next stage of its improvement, are three friction wheels, by which the machine contained 360 plane mirrors, each eight inches moves horizontally. O, a strong iron bow, in long, and six broad, mounted on a frame eight which the lens and the cone hang. Section. fig feet high, and seven broad. With twelve of these 2. a, the great lens marked A, in the elevation. mirrors, light combustible matters were kindled b, The frame which contains the lens. c, The at the distance of twenty feet; at the same dis- small lens marked B. d, The frame which contance a large tin vessel was melted with forty- tains the small lens. e, The truncated cone, five of them, and a thin piece of silver with 117. marked C. f, the bar on which the apparatus When the whole machine was employed, all the marked F moves. g, The iron plate marked I. metals and metallic minerals were melted at the h, The cone of rays formed by the refraction of distance of twenty-five, and even of forty feet. the great lens a, and falling on the lens c. i, Wood was kindled in a clear sky, at the distance The cone of rays formed by the refraction of the of 210 feet. The focus, at the distance of fifty lens c. Front view. fig. 3, k, The great lens, feet, is about seven inches broad; and at the 1, The frame containing it. m, The strong iron distance of 240 feet, it becomes two feet in dia- bow in which it hangs. From a great number of meter. Buffon afterwards constructed a machine experiments made with this lens, in the presence which contained 400 mirrors, each half a foot of inany scientific persons, the following are sesquare, with which he could melt lead and tin at lected as specimens of its powers :the distance of 140 feet. He observes, that in large refracting lenses, which are most conve- Substances fused, with their Weight in Time in nient for many purposes, the thickness of the weight and time of fusion. Grains. Seconds. glass in the middle is so great, as very much to Gold, pure . . . . . . 20 diminish their force. For this reason he pro- Silver, ditto . . . 20 poses to form a burning glass of concentric or Copper, ditto . . . . . 33 circular pieces of glass, each resting upon the Platina, ditto ... other. His method is to divide the convex arch Nickel . . . . . of the lens into three equal parts, 'Thus, sup- Bar iron, a cube... pose the diameter to be twenty-six inches, and Cast iron, a cube . .. the thickness in the middle to be three inches : by Steel, a cube . . . . . . dividing the lens into three concentric circles, Scoria of wrought iron ... . 12 and laying the one over the other, the thickness Kearsh . . . . . . of the middle piece needs be only one inch; at the Cauk, or terra ponderosa . . same time that the lens will have the same con- A topaz, or chrysolite.. vexity, and almost the same focal distance, as in An oriental emerald . . the other cases; while the effects of it must be Crystal pebble . . . . much greater, on account of the greater thinness White agate . . . . of the glass.

Flint, oriental . ..

30 · Mr. Parker's lens is three feet in diameter, Rough cornelian ..

75 made of flint-glass, and which, when fixed in its Jasper . . . . . . frame, exposes a surface 2 feet 8 inches in the Onyx · · · · · · · clear. The elevation is represented on plate Garnet . . . . . . .

17 XLV. fig. 1. A, is the lens of the diameter White Rhomboidal spar..

60 mentioned: thickness in the centre, 31 inches: Zeolites . .

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23 weight 212 pounds : length of the focus, 6 feet Rotten-stone . . . . . .

80 8 inches; diameter of ditto, 1 inch. B, a second Common slate . . . .. lens, whose diameter in the frame is 16 inches, Asbestos . . . . . .

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10 and shows in the clear 13 inches: thickness in Common lime-stone . .

55 the centre 19 inches : weight 21 pounds : length Pumice-stone. ..

24 of focus 29 inches : diameter of ditto, of an Lava . . . . . . inch. When the two above lenses are com- Volcanic clay .. . .. 10 pounded together the length of the focus is 5 Cornish moor-stone . . . feet 3 inches: diameter of ditto, half an inch. C, a truncated cone, composed of 21 ribs of A subscription was attempted for the purpose wood : at the larger end is fixed the great lens of defraying the expense of this fine instrument, A, at the smaller extremity the lesser lens B: but it failed; and the instrument itself was purnear the smaller end is also fixed a rack D, chased by captain Mackintosh, who accompanied passing through the pillar L, movable by a lord Macartney in his embassy to China ; and is pinion turning in the said pillar, by means of now probably deposited among many ingenious the handļe E, and thus giving a vertical motion and valuable presents, the use of which is un to the machine. F, a bar of wood, fixed between known to the Chinese. the two lower ribs of the cone at G; having, BURNING PLANT. See EUPHORBIA.

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