», Wea ae a rey” ay * > Lp ay 3 ‘t . &. oar v7 7 A yan : - ‘ae OnE PEP « 4 ate A ak ip Le 4. a aye ae €. * , 5 i Saltire 4 w ‘ 4 Ly IN 4 the Ee s w: 4 Kobe ede 0 Abe 0 decyl ss RG tee Ce cea. dee 1an 10n c fe) D GS RS Sm Inst itut Purchased from the CULLMAN ENDOWMENT BRITISH MINERALOGY: OR COLOURED FIGURES INTENDED TO ELUCIDATE THE MINERALOGY OF Great MWritatt. BY JAMES SOWERBY, F.L.5. HONORARY MEMBER OF THE PHYSICAL SOCIETY OF GOTTINGEN, DESIGNER OF ENGLISH BOTANY, AUTHOR OF ENGLISH FUNGI, ETC. (With Assistance.) a As for the Earth, out of it cometh Bread, and under it is turned up as it were Fire. The Stones of it are the Places of Sapphires; and it hath Dust of Gold. Jos xxviii. 5, 6. ee VOLT: SE ————— LONDON: PRINTED BY R. TAYLOR AND CO., BLACK-HORSE-COURT, FLEET-STREET ; And sold by the Author, J. Sowersy, at No. 2, Mead Place, Lambeth: and by Wuire, Fleet-street; Symonps, Pater-noster-row; and all other Booksellers, MDCCCTY. re det ene ie gen Che ya Sr he wth : eh ks nina? ae sk Ke oh a me aS f dae é Bi oe Ce igure te a AE aM F # 4 Re PMU ae A 2 TAB.” VIL. »-CALX. Creta. Common Chalk. Class 2. Earth. Order 1. Homogeneous. Gen. 1. Lime. Spec. 2. Carbonate of Lime. Div. 3. Amorphous, syn. Chalk. Kir. v. 77. Craie compacte. Born, v. 1. 281. Chaux carbonatée crayeuse. Huiy, v. 2. 166. Creta scriptoria. Linn. Syst. Nat. v. 1.206. Gmel. Dege oO; Axuzion cliffs, famed of old, are the chalk-hills of Dover in Kent, and chalk is sufficiently known to abound in many parts of Britain. There is no chalk in Cornwall*. Chalk is understood to he a precipitation of carbonate of lime, holding a little clay and some flinty particles. It is often in very thick strata, frequently under sand. Flints in strata and of irregular forms are very common in it, and sometimes flints full of flaws, as if mouldering to pieces. Thestratum is mostly horizontal, but sometimes otherwise, as at the Isle of Wightt. Many remains of animal exuvie are found in chalk, as shells, echini, corals, &c. and with the rhombic, frac- ture: sometimes the echinites are filled with perfect flints. * Dr. Maton’s Tour to the Western Counties. } Sir H. C. Englefield in Linn. Trans. % 6. 16 Martial pyrites, or sulfure of iron, is not uncommon in it, either in full metallic splendor, or in different states of decom- position passing into ochre or oxid of iron. It is remarkable that Mr. Kirwan, in his Geological Essays, p. 238, says that metallic substances are never found in chalk. Werner Kal. Classif. 19. Berg. Kal. 232. Yetin France martial iyztes are said to be found in it, 39 Rozé 3585 as if Fi were ‘not fou ound in England, Pyrites are found in the chalk of Stissex ; I fave fara” them from Dover to Margate ; 3 at Godstone alsé. in great abundance, where the chalk in various ways passes. into fine-grained micaceous lime-stone called fireestone, brought in abundance from Ryegate. ps The upper figure is meant to represent a lump of chalk from ‘Sussex, which has a conical fracture not uncommon in chalk, and sometimes in flint.. The little granule of fine gravel so regularly formed about. it, seem to bea filtration of water carrying sand with it through some loose chalk, which meet- ing with a more compact piece runs down the sides in drops, and at the same time is absorbed by the chalk, leaving the sand on the surface in little globules. There are sometimes large quantities of sand in the chalk which fall in occasion- ally, and are called by the workmen sand gulls. Middle figure. Chalk passing into lime-stone, hardening with inosculating veins. The lower figure represents a piece of chalk rounded by rolling about in the sea, perforated by the Mytilus rugosus, or some species of Pholas : bemg stained it loses the appear- ance of chalk. Harder swbstances are often perforated by testaceous animals. «- fe Bryum calcareum, English Botany, t. 191, “chould seem to indicate good chalk, as [ have found the best where it grows, ie » iy ai Ky oh ae : Deel! 1802. Fathfhed by Ja? Sowerhy; Londen TASB Wa CALX petrosa. Lime Stone. Class 2. Earth, Order 1. Homogeneous. Gen. 1. Lime. Spec. 1. Carbonate of Lime. Div. 3. Amorphous. Syy. Pierre a chaux commune. Born, v. 1. 284. Kalxstein. Emmerling, v. 1. 437. Compact limestone. Kir. v. 1. 82. Chaux carbonatée grossiére. Haiy, v. 2. 166. ~ Limestone, generally speaking, is carbonate of lime, harder than chalk, often containing 10 or 12 per cent. of clay or iron. Ifso much as 15, Mr. Kirwan says it should be excluded, as scarcely affording good lime in burning. Upper figure. Ketton-stone, found in abundance at Ketton in Rutlandshire. It is remarkable for its singular ac- erections in the form of fishes roe, whence it is often called i 18 Roe-stone. Jt is used for building in many places: some of the colleges at Cambridge are built with it. The same uniform appearance extends to very large masses; and al- though a sound, strong and durable stone in the mass, very little pieces may be crumbled to grains by the fingers. The masons use a common carpenters saw in working it: the little rounded particles being easily detached, it passes readily through it. They sometimes have a little dusty or solid nucleus, coated concentrically; at other times are hollow. In the next county, Northamptonshire, there is a stone called by the masons Barneck, greatly resembling this, but coarser, containing shells, &c. Col. Walford found a stone of a similar nature with larger grains (which approaches the oviform limeftone of Kirwan, v. 1. 91), at Birdbrook, Essex, mingled with shells, which has sometimes sufficient clay or argil to be called a marle. Middle figure. Bath-stone, frequently contains the same concretions, but more decomposed, and a matrix surround- ing them, somewhat confusedly crystallized, forming little hollows: many species of shells, encrini, &c. are found in it; sometimes however so comminuted as to be quite indistinct. JI picked up a piece of stone at Burford in Oxfordshire, which is of a reddish brick colour, with the hollows very distinct, giving it a volcanic or cindery appear- ance. With difficulty very small pieces crumble between the fingers. Lower figure. Portland-stone, nearly like the Bath-stone. The best sort is more compact, and whiter: there are many 1 varieties of it, paffing into marly, flinty, &c. It often affords good crystals. The specimen figured had some little rhombs half relieved on it. A crystallization called, from its resemblance, sugar-candy spar is frequent among it. Shells of various kinds are often found in it. Sometimes it appears in the form of large trunks of trees, hardest with- in resembling whitish chert. Ketton-stone, colour light reddith brown, lustre o. Transparency o. Fracture earthy granular. Hardness 5 or 6. Tt contains go per cent. calx, and10 of ‘argil. The Bath and Portland nearly the same in most respects, but harder, Spec. grav. Ketton 2°456 Bath | 2°494 > Kir. v. 1. 88, Portland 2°461 Jan?1 18503 Publijned by Ja? Sowerky. London TAB. IX. CALX coralliformis. Coral-form Carbonate of Lime. Class 2. Earth. Order 1. Homogeneous. Gen.1. Lime. Spec. 2. Carbonate of Lime. Div. 2. Imitative. Ellis corallines, p. 76. tab. 27. c. Tuese curious-chalky accretions are found plentifully in the loose marle at St. Maws, Cornwall, which abounds also with shells of various species, and is brought to Truro to be sent to different places for manure, being excellent for the adjoining lands. I have specimens from the Rey. H. Davies of North Wales. Their resemblance to corals has caused them to be mistaken for such; but on a careful examination, they are found to be only aggregations of calcareous earth, accumulated upon little nuclei, ramifying in the soft marle, and occasionally attracting other calca- reous particies, which form fresh coats like the bark of a tree, and are not unlike the coats on the nuclei of the 22 Ketton stone lengthened out, as the broken ends plainly show. They vary extremely in their forms, and when large are sometimes perforated on the outside, apparently by some marine insects; which may have contributed to the idea of the whole being of animal construction. Nature ever allotting certain bounds to every species of her pro- ductions, permits them to separate from one another in many nice and curious ways. Thus calcareous earth in this instance is separating from the clay in the form of opaque branching corals; in others we shall find different modes of separation or division of calcareous earth and other substances. The small specimens are very much branched, and mostly white, but somewhat softer to the touch. The larger are often more coloured with iron, perhaps some animal sub- stance, as the place in which they are found contains many dead shells. Sometimes they contain some salt, which is readily perceived by the taste, and remains after drying in the cabinet. Some have no saline taste. me oF, hu y2 , tes i Ny ta tae pie TD Hp ayy vr ete ay y “ton LO TAB; xX. FERRUM = ceruleum. Azure Iron Ore. Class 3. Metals. Order 1. Ductile. Gen, 8. Iron. Spec. 7. Azure Iron Ore, Spec. Car, Contains sulphur? and iron. Syn. Blue martial earth. Agr. v: 2..185. Blau eisenerde. LEmmerling, v. 1. 359. Fer azuré. Hauy, v. 4. 119. Tuts is very common in marshy grounds at different depths in most parts of the united kingdom. The upper figure represents some as found at Blackwall, or the Isle of Dogs, where great abundance was met with about four feet deep, in a sandy loam, mixed with roots and other vegetable remains. At the depth of about nine feet, in some places, it was mixed with a black clay, turf, leaves, hazel-nuts, 8c. It occasionally exists among earth with the remains of shells, and is common in marshy places without any appearance of vegetable. [I found some once on the shell of the Mytzlus anatinus in Hyde-park, and have had it sent me from Scotland. 24 The lower figure represents it as found near Kennington and Lambeth, where it is common about a foot under the roads in a dirty gravelly soil, partly hardened and approach- ing to what is commonly called pudding-stone. It adheres to the pebbles, but more particularly to the hollows where they have been. In endeavouring to ascertain the nature of this substance, we exposed some of the purest of the first sort to a gentle heat, which soon deprived it of the blue tint, emitting a sulphureous exhalation, with a blueish flame, and left a dark ochry brown substance, which proved to be an oxid of iron. We could not detect any prussic acid by the usual method. Mr. Kirwan says, its colour, inits native situation, when not exposed, is white. This may sometimes be the case, but ours was blue even when fresh gathered and first broken. Lustre none. Fracture dusty, of the upper figure ; earthy and compact in the lower. Water does not change the colour; oil darkens it. Klaproth thought this mineral contained phosphorus, but Mr. Kirwan thinks “ the inflammability of this substance must proceed from some other principle, most probably carbon, perhaps an astringent substance.” Z, a il TAB. XL. CALX Fluor, var.-cubica. Fluate of Lime, Cubic. Class 2. Earth. Order 1. Homogeneous. Gen. 1. Lime. Spec. 4. Fluate of Lime. Div. 1. Crystallized. Spec. Cuar. Lime combined with fluoric acid, which acid has the peculiar property of dis- solving siliceous substances, or flint. Chaux fluorée. .Born, v. 1. 355. Fluss. Emmerling, v. 1. 515. Fluer. Kirwan, v. 1. 124. Chaux Fluaté cubique. Haiy, v. 2.247. At At I z Fivor is divisible into regular octaédrons. Spec. grav. 3°0943 to 3°I911, and according to Haiiy has a regular te- traédron for its integrant molecule. It is mostly found crystallized in cubes (more rarely in octaédrons and their modifications) in many parts of Great Britain, as Derby- shire, Cumberland, two places in Scotland*; also in * Aberdeenshire and Shetland. Jameson, v. 1. 151. 26 Devonshire and Cornwall. It may be fused by the blow- pipe into a transparent glass*. Its refraction is single. The powder projected on a hot poker gives a phosphorescent light, of a bright and glowing purplish or lilac colour. The Rev. Mr. J. Dalton favoured me with some from Cumber- land, greenish within, and of a dull pale crimson on the outside, which gives this glow in great perfection, in rather large pieces, without cracking or dispersing so soon as usual ; and if not too much heated, the same pieces will do again. In this it agrees with the chlorophane of Siberia, which much resembles it in external appearance, but gives a vere diter green glow on exposure to heat without falling to pieces, | The fluoric acid was discovered by Scheele. It may be disengaged from the lime by means of dilute sulphuric acid, and has been used for etching on glass. One of the methods may be acceptable to my general readers. Having a plate or piece of glass thinly covered with wax, etch, or draw, by cutting through the wax with a point or needle whatever may be desired, placing the glass horizontally, so as to retain the fluid, (it may be best perhaps to surround the plate with a wall of wax, for the greater security); then having some fluor pounded to a fine dust, sift or spread it over the whole within the waxen wall. Mix one part of sulphuric acid to two or three of water, and pour it on gently. The strength of the strokes will depend on the quantity of dust of fluor, and the strength of the acid * It is apt to crack and disperse ; which may be prevented by powder- Ing if. 2¢ that is to decompose it. ~ Very little practice will show the proper strength of the ingredients to corrode a certain depth in the glass, where the strokes were drawn. The rising fumes will etch another prepared glass, if placed so as to receive them, and perhaps more regularly. The acid for chemical purposes is commonly procured in a leaden ap- paratus. I have figured two specimens of the most common ap- pearance of fluor. The upper one deviates a little in form, the middle cube being interrupted by the side ones, con- tracting its upper part, so that the lower is much the broadest. There are some crystals of what is commonly | called eighteen-sided quartz sticking about them, as usual with fluor from Cumberland. The lower figure seems altogether of a fine deep purple, but is only thinly coated, the inside being of an olive green. The faces are remarkable for having signs of the lamine of superposition, indicating four-sided pyramids, the apex of which appears at the edges of the cubes where in contact. Fig. 1. shows a corner of one of the cubes replaced by six minute triangular facets. The upper figure has some signs of superposition, though scarcely more than scratches, giving the specimen a greasy appearance. The hexangular cavity is where a crystal of guartz had stuck, and shows that the side inserted was not regular: hence it appears that the crystals of quartz are not regularly eighteen-sided, their shape being interrupted by the fluor. SRG ha ” Oy hal i "7 é fs 4 ' + i c . ‘ 4 ) re Sebel 4 , + > E “ : / y 7 7 > i 5 2 a hay) ee ‘5 “ . gt 4 § ‘ y a he a , , : , 4 i J , P ' Tene 4 a i * Ae ys ; beg ' / p i Z ~ i ‘ ste : , z nn ‘ ; ‘ my ’ %. ; “ " j F e ‘a ' ’ ? - ‘ = 4 + A i ea « ry 4 : ‘ . “ = j v » a 4 * r r * al hc Lhe 78 4 = P saith a : os _ ia Pied * 3 is : ~ ‘ + ‘ , a i F i Cee te ) » +; ‘s kas / yok i) bet Bai 25 7 * ne eghs ; 4.2 1803 Fidbtifhed by Ja‘ Sowerby London . (PA Bo ex: CALX carbonata, var. equiaxi-lenticularis, Crystallized Carbonate of Lime, lenticular- equiaxed. Class 2. Earth. Order 1. Homogeneous. Gen. 2. Lime. Spec. 2. Carbonate of Lime. Div. 1. Crystallized. Var. 1. Equiaxed. Tue figuring of this shell will not only serve a geological purpose, and show a curious crystallization, but help to explain the flattened crystals in the next plate, which are not easily understood, as the lines they form in the draw- ing give but little idea of flatness, and may seem to express the perspective of a cube, especially as we are not yet much accustomed to these representations. This is the Helmintholithus Ammonites of Linn. Gmel. VY. 3. 411. usually called Cornu-ammonis, of which there are many species found in the petrified state*, abundant in * This species and many others are found only in this state, never recent. “ 30 many parts of Gteat Britain. Abroad they are often siliceous, or at least contain siliceous crystallizations ; but in Great Britain are mostly calcareous, found in lime-stone rocks and marly places. The shelly part may some of it be the remains of organic structure. The crystallized internal parts of shells and stones afford a curious subjeét for in- quiry. In the chambers of this nautilus, (for so the living genus is called by Linnzus, see Gmel. v. I. 3369., the matter of crystallization may have passed ‘through the alveolus, or little hole, "to each partition. In other shells, and in geodes, it must be otherwise. The crystals are rough, and in nearly a regular series from the primitive to the equiaxe. The faces however of the latter are rounded, - giving italenticular form. They are alsosomewhat striated, resembling the lenticular crystals of certain spathose iron ores. Febl1 1802 Publtined by zr da * Sowerky, London 13 TAB. XIII. CALX carbonata var. equiaxis. Crystallized Carbonate of Lime, var. equiazed. Class 2. Earth. Order 1. Homogeneous. Gen. 1. Lime. Spec. 2. Carbonate of Lime. Div. 1. Crystallized. Var. 1. Crystal Equiaxed. B Syn. Chaux carbonatée équiaxe. 1. Haiy, v. 2.132. g er Tuts crystal is formed of six rhomboidal faces the angles of which are 114° 18'56//, and 65° 41’ 4", forming a very obtuse rhomb, the axis of which is equal to that of the thomb whichit encloses. Haiiy, v. 1. 133. These and their modifications are found plentifully in Durham and Cumberland, according to specimens sent me by the Rev. Mr. Harriman and Mr. Oliver. I have had fine specimens from Newcastle by favour of Mr. Wood- house, found in coal mines. They occasionally occur wherever other calcareous substances are found. The upper figure is part of a fine specimen with clearer crystals than usual, for they generally incline to a milky / 32 hue. They frequently stand on their edges, or are as it were thrown about in different dire€tions, on various matrices. This is on dark or gray lime-stone, with blend* and galenat. The first is confusedly crystallized, which commonly happens; the latter more regularly so, in cubes with the corners truncated, or acubo-octaédron, as Hatty rightly terms it. The lower figure has smaller crystals, roughish towards the edges, as ifnot quite finished. The roughness proceeds from the edges of the molecule, or from spaces where there seems something wanted to finish the faces and make the surfaces even. The crystals are somewhat striated towards the centre, and are loosely fixed among light purple fluor and galzna. * An ore of zinc called by the miners black jack. + An ore of lead. Feb? 1803 Evblifhed by Ta? Sowerby: London. TABS KV i : "ee > sp ARIGIL LAvcMargas: bot 101 Argillaceous Marle. Se ee “@ Class 1. Earth. Ord. 2. Mixed. on Gen. 5. Argil*. Spec. 1. Argillaceous marle. ’ Div. 2. Semi-indurated. Spec. CHar. Argil and carbonate of lime, in which the former predominates. whl / Syn. _ Marga argillacea. Waller, v. 1..'72.), Mergel. Emmerling, v. 1. 491. La Marne. Brochant, v. 1. 569. , Argile calcarifére. Hauy, v. 4. 455. rae * — MEE Tuis is represented as showing the distinguishing charac- ters, or parts, of marle, which, if minutely combined, might require a chemical analysis to determine them; and may be useful to young mineralogists. Calcareous marle consists of carbonate of lime from 66 to 80 percent. Kir. v.1. 94. Maile properly so called consists of equal parts of clay, and carbonate of lime. Argillaceous male contains about three parts clay, and one chalk. Mr. Andreas, in Kir. v. 1. 192. * Common clay, which may be distinguished under most combinations- by what is commonly called an earthy scent. D 34 The present specimen, given me by Mr. Pilkington, F.L.S., was found about 190 feet deep, in digging a well for Lord Redesdale, now C. Poole’s, Esq. at Streatham, Surry. It is of a semi-indurated toughish texture, but readily falls to pieces in a damp-atmosphere.. The clayey parts are evi- dently mixed with carbonate of hme, and some of the shells are little else, although they retain their original figure so well that we may distinguish some of. the species*. The pearly oyster shells only seem to have assumed a black tinge. ‘The other pearly shell, perhaps Arca Nucleus, Linn: Gel. v. 1. 3314. retains its original lustre, its gluten being less easy to decomposet. There are other pearly shells in the mass, but not easily to be made out. The clayey-looking part does not effervesce with vinegar, neither do the pearly shells. The chalky ones readily do. Marles depending on their proportions of lime, clay t, orsand, are used as manures, each sort being adapted to the nature PF the land they are “applied to, One kind of marle has lately been found to be a useful stucco, when properly prepared. * These, om breaking the mass, leave half their substance-on the convex side of the matrix, and the other half i in the mould. + See Mr. Hatchett’s ingenious péper in Philosophical iansaetion for 1798. + Clay must be understood as a mixture here of argil, silex, and iron. UD 11503 Pubhfhed ty Ja® 8c werby:;London . i rod] PAu eo Oy ol » 918 eald SILEX arenacea, var. calcarea. : Calecareous Sandstone. Ciass 2. Earth. Ord. 2, Mixed. Gen. 6. Silex. | Spec. 2. Combined with calcareous Earth. | Dw. 2. Semi-indurated, Syn. Calcareous sandstone. Kir. v.1. 361. ee Masses of this, from about 8 inches to 2 feet thick, were found at near twelve feet deep in a light gravelly stratum, in cutting the canal at the Isle of Dogs, The decomposing shells have apparently undergone a change, by means of subterraneous heat causing them to combine with the sand and pebbles. Some of the shells I believe are new to Great Britain, both im the natural and fossile state. These are the ‘gibbous Arca, at the lower corner on the right hand, the hinge and cockle-like edge of which are seen distinctly above it; the oblong Arca resembling a Mytilus, on the left side, showing part of the hinge, which I have not seen in any other specimen. The decomposition of this shell, and the Turbo near it, are more chalky than the others. The oblong 36 oyster shell at the top retains its pearly lustre. Other shells have only left their impressions or cast. Some of the peb- bles are cracked with the heat, and their interstices filled by calcareous matter. The whole forms a calcareous sandstone, with very little variation, and is,of a,pale brown colour*. _ The parts being distinct, it forms an instructive specimen, and will serve to explain more obscure ones. 3 ** Sometimes with a darker tint of yellow, and occasionally of a smoky black, especially where wood is found with it. Feb71. 1803 Eublfhed by Tas Sowerby,Londom . dA. hex Va ARGENTUM capillaceum. .. Capillary Silver. eee Class 3. Metals. Ord. 1. Ductile. Gen. 3, Silver. Spec. 1. Native Silver. Div. 2. Imitative. Gen, Cuar. The whitest of all known metals, very malleable, and sonorous ; specific gravity before hammering, 10°474; after, 10°510. Dissolves readily in nitric acid, and may be precipitated from it by copper, iron, or zinc. Remains in fusion at 28° of Wedgewood, but requires a greater heat to fuse it. Spec. Cuar. Ductile with but a small proportion of alloy. Syn. Argentum nativum. Waller, v. 2. 328. Linn. Syst. ed. 12. v. 3. 148, Native silver. Kirwan, v. 2. 108. Bab. 146. Gediegen silber. Emmerling, v. 2. 153. Argent natif. Hazy, v. 3. 384. a In June 1799, soon after the discovery of native silver in the Herland copper mine, in the parish of Gwinear, about 7 miles from St, Michael’s Mount, I had the pleasure of 38 calling there in company with my friend D. Turner, Esq., and was lucky enough to procure some rich little pieces, which served my purpose, and gave me the most satisfactory pleasure of gratifying a few friends. According to the Rev. Malachi Hitchings’s account, in Phil. Transac. for 1801, page 169, “ the lode in which it occurs is one of those cross courses which intersect and derange the copper lodes, and are consequently of a more recent formation. No ores of silver were observable in this lode till at the depth of 110 fathoms from the surface, and at the further depth of 32 fathoms they disappeared. The richest mass of silver ore was fourtd at the depth of 2 fathoms above the level at which it disappears. About 108 tons of it are said to have been raised. The silver ore, strictly speaking, is a mixture of galeena, native bismuth, gray cobalt ore, vitreous silver ore, and native silver.” Our specimen seems to be the galena decomposing and ‘protruding the silver; itself remaining of a cinereous ap- pearance, losing its natural brilliancy. There are also some pyrites and bits of quartz. The silver protruded is nearly pure, and has been (from its curling appearance) compared by the people of Penzance to the scrapings of silver spoons. The silver for comm and manufacturing is alloyed with copper, which does not affect the whiteness, and is not easily de- tected, unless in too great proportion, when it may some-— times be tasted. It may be made very thin as leaf silver, one grain thus formed measuring more than 51 square inches. It is often used to plate over copper or iron, and. 39 wire so made serves for musical instruments, &c. A wire one tenth of an inch in diameter will support 270 pounds weight. Silver, by being dissolved in nitric acid, and precipitated with, mercury, will form the likeness of a tree, and is then called Arbor Diane.—If precipitated from the nitric acid by lime water, the precipitate dried, and washed with a solution of pure ammoniac, has a dangerous fulminating property ; and on the slightest touch, or friction, will explode most violently, exceeding the force of gunpowder. The nitrate of silver stains animal substances a deep black, .and has been used to blacken human hair; but it is extremely dangerous, owing to its corrosive property. aaiw ehnts muse, ba + Ve ade / bs et ebrirrog OCS Hoag (92, re W ‘tofomns' 5 G's 8 we oe ’ A oinh asiniag aioe! f 1 oroganh ee 40 ri gong sy tig saya tA b+ London. TAB, XVIL CUPRUM dendriticum. Dendritical Copper. Class 3. Metals. Ord. 1. Ductile. Gen. 4, Copper. Spec. 1. Native. Div, 2. Imitative. Syn. Cuprum nativum. Waller, v. 274. Linn. Syst. ed. 12. v. 3. 143, Gediegen kupfer. Emmerling, v. 2. 206. Cuivre natif. De Lisle, v. 3. 305. Haiy, v. 3. 518. Native copper. Kirwan, v. 2. 128. ee SL ee Nor uncommon at the Lizard and other places in Cornwall, in the crevices of quartzose rocks, or in serpentine, and is oc- casionally found in North Wales, &c. It accommodates itself n all directions to the smallest openings, ramifying, or inos- culating, as in thespecimen figured, or forming network. It is generally so compressed as to have the impression of the stone on the surface, giving breadth to the extremities, not unaptly resembling foliage, which is often helped by the tendency of the metal to crystallize. This it always partly does, but in so confused a way that it can only be under- stood by comparison with such specimens as have had more 42 room to crystallize. This will be readily understood by the figure of what I have called Arborescent Copper. _ Copper is so well-known in Great Britain as scarcely to need a description. The fresh fracture is very hackly, mostly brighter, and lighter in colour, than the outside, which is often stained or cankered. It is however sometimes found so pure, or bright, that it changes but little; and the fracture will hardly show a difference of colour, if carefully kept. Hardness 6—8, Kirw. Steel cuts it neatly, whence it is made into plates for engraving on. - It is soluble in acids ; and aquafortis is used by artists to etch upon it with the help of wax, not unlike the operation spoken of under the article Fluor, tab. xi. of this work. It is manufactured for many purposes, as common coin and kitchen utensils, but is not now so much used for culinary purposes as formerly. It forms a compound metal with tin and zinc, called brass. It is readily drawn into wire, which is very tough and durable. A wire one-tenth of an inch in diameter will sustain 2994 pounds weight. eres with 5) ties As Ai 1805 Fd faed by Ja | Sewerky- Loaden 18 TAB. XVIII. STANNUM oxygenizatum.. | Orygenized Tin. ane ——— Class 3. Metals. Ord. 1. Ductile. Gen. 8. Tin. Spec. 2. Native oxide. Di. 1. Crystallized. Gen. Cuar. Nearly as white as silver, malleable, ductile, and sonorous in a small degree, flexible, but with a crackling noise. Spec. grav. only 7-063 to 7°331. Smell unpleasant. Fuses at 410° _ Fahrenh. Not soluble in nitric acid. Spec. Cuar. ‘Tin united with oxygen. Syn. Common tin stone. Kir. v. 2. 197. Zinnstein. LEmmerling, v. 2. 421. Etain oxydé. Hauy, v. 4. 137. Stannum crystallinum. Linn. Syst. ed. 12, v. 3. 130. oo a ‘rx, although universally known in the metallic state as obtained from its ore, would never be recognizable without experience in the crystallized oxide, from which it is chiefly procured. ‘This crystal was once thought, by the Cornish miners, to be destitute of metal. The tin mines of Corn- wall are the most famous in the world, and were very early known. ‘The Pheenicians procured this metal from thence. 44 The Cornish tin ores are said to be the most pure, as they contain less iron and arsenic than those of Bohemia, Saxony, &c. The crystals are mostly confused : specimens however are sometimes found (and preserved to gratify the curious) which are very distinct and beautiful. They resemble bottle glass; are mostly of a black hue, approaching a brownish horny lustre ; sometimes brighter, and with a fiery sparkling, varying to red, gray, or whitish. The crystals are the cubic or octaédral modifications: the perfect cube has never, I believe, been found. The octaédron, I am told, is perfect in the Honourable Mr. Grevyille’s collection. I have one nearly so. They often press against each other, forming macles, &c. This ore is found varying, sometimes amorphous, in the quartzose, decayed granite, or growan, killas, and other rocks: also in streams, and is then called stream tin. It occurs also in pebbles, and sandy particles. A rare species, called wood tin, or tin hematites; also an- other called tooth tin, and sulphuret of tin, are found in different parts of Cornwall. There is very little tin in Devone shire, and none in any other county of Great Britain. LE —< SLES Niue Pitlititeed U- Jal Somerby, London TA Sa ‘CALX carbonata, car. margaritacea.— Pearl Spar. ho oe Class 2. Earth, Ord. 1. Homiogeneous.:. Ly Gen. 1. Lime. Spec. 2. Carbonate of lime. Div. 1. Crystallized, crystal primitive. Var. With some iron and manganese. Lustre pearly; crystals / often curving. Syn. Spatryiron ore. Kir. v. 2. 190. Spathigereisen stein. Emmerl. v. 2. 329. Werner. Chaux carbonatée férifére.. Haiy, v. 2. 175. Pearl spar. Bab. 18. - se Havrne so distinguished an appearance from other car- bonates of lime, this has obtained the name of pearl spar, a name it naturally suggests, and by which it is in general easily recognized. We find however, like other subjects in nature, it has its gradations, and consequently blends itself with substances to which at first it seems very little allied. it may be readily traced, as formed from the primitive crystal of carbonate of lime, to an iron ore, consisting for the greater part of oxide of iron, and manganese. The progress, if I may so call it, appears curiously and distinctly marked by — the manner of the crystals, which are in the forms of the primitive rhombs, and are white: sometimes however it approaches the appearance of ivory; and as its substance 46 becomes pearly, the nuclei seem to be separating and curv- ing from about the angle of 30° to about 20°; see the figures. They mostly appear of the natural pearly lustre, but are often at length more curled and darkened, and thence may be called spathose iron ores: perhaps they may be called iron ores whenever the common browner aspect seems to indicate as much. Those, however, which have the forms and fracture of crystallized carbonate of lime may be placed as such while they retain the whitish pearly lustre. Pear] spar analysed by Bergman contains fine te Ginaare a aree baste Oxade OE 1hom 5 a5)s..'. Cicer 38 Oxide of manganese ........ Behoy.! 100 By Wolf, Carbonate of lime ......... er iG Oxide of manganésé- 7... . 2... 35 Tron *e@®eeervrervseserteeese a@eeeeeese 5 100 By Berthollet, Carbonate of lime ..... lp BRO aT. 96 Oxide of iron and manganese .. 4 100 Thus different analyses, showing a difference in the pro- portion of the substances of which it is composed, decide it to be more or less afi tron ore. ‘ eben Sr Ja> Sowerby. Londen TAB: XX CALX carbonata primitiva, var. Primitive Carbonate of Lime, var. Class 2. Earth. Ord. 1. Homogeneous. Gen. 1. Lime. Spec. 2. Carbonate of lime. Var. Crystal primitive, with secondary faces parallel to both those of the equiaxed and metastatic. SEE Tuts curious crystal is sometimes found at Castle-Town in Derbyshire. Its gangue is generally a bituminous limestone. It is a little milky on the outside, and roughish ; those edges excepted which are rounded : see the left-hand figure. The right-hand figure has broad faces leading to the equiaxed crystal, which faces are as it were polished, and in the mid- dle is a longitudinal line showing the edge of the nucleus, consequently the amine of superposition: see the upper part of the right-hand figure. There are also rough faces leading towards the metastatic crystal: see the lower part of the right-hand figure. As I had but indifferent specimens myself, I borrowed the specimen here figured of Mr. Richard Phillips, thinking it well worth noticing. The little black spots are drops of mineral pitch, which mostly accompany these varieties. They have generally been termed primitive crystals, without further consideration. In an arranged col- jection they may be placed near to the primitive. sii if vidtering, stauodtss x r ko > ane aml to orngod ad sation we v xO | sa af Tee ar 3 ce scot Abbr! a Ble hove Lee ooniaa zi Sas i me fi oF HOI [- alten io. bash bartitesros at i istayra uot’ onl + \pnotesenil euonitnaids: vlsvagan ai singrisg ast. ae aaab9 acon § : etdaus oy bre Obrehig ait. ao VALE S yl Bat at olT or gan tusnd-fisl. ods aaa 2 be ahs suet 918 oiler. batqaox boxsiipa ort, ob aniisal ey: A beord ead orogit ba -binr oct ai bag hodeilog sivw ti 25 ais asoph doistyr 7 gusloun od toy ag09 dit qarvords ‘anil lnnibuitgnol 8 ial ‘yoqqu acd 298 Paeiizagiequa to maicsl odd vinsuponao 2aont- dguot.'oels ous sion Y igh basd-sileis oa} ’ - tneq ‘sowol adh s92°: Ieteyr, oitsiestont odd alruavitt et anocisoge janeGibai sud bed | 2A sug bees ~ brgilotfl Mv tes baat svod esirtioage: ont 3 We Aosid obs ott .giiviton dio, iPewne 3 rasyisoo? pie? dbirie totigg Twrottin | zvititng bacirot wood joni oestt gal 21 Ap? 2 1803 Pubhifhed by Ja” Se udun TAB. XXI, Upper Figure. CALX sulphurata; var. plumosa. Sulphate of Lime; var. plumose. EEE Class:2. Earth. Ord. 1. Homogeneous. Gen. 1. Lime. Spec. 5. Sulphate of lime. Div. 2. Imitative; var. plumose., Syn. Sulphate of lime forming snow-white incrusta- tion, &c. Bah. 29. ccxvi, a, 1. Chaux sulfatée niveforme*. Haty, 2. 279. - =e Tue upper figure is a curious variety of sulphate of lime, or gypsum, from Matlock. It should seem that sulphur of iron or pyrites, by exposure to damp, decomposes; the sul- phur combining with oxygen forms sulphuric acid, which comes in contact with the lime in the rock, and 50 forming gypsum, oozes out in these fanciful forms; or, in other words, readily produces gypsum more or less crystallized. It is continually forming in many parts of England. Lord Altamont obligingly sent me some nodules of pyrites, in * A variety found at Montmartre. EB 50 which gypsum is formed, from a well just dugin Cambridge. It is continually crystallizing from the sulphur of pyrites and oysier shells at Shotover Hill, near Oxtord. The lower figure is on a piece of limestone with a feetid odour, called stinkstone, the gypsum spreading in a very peculiar manner on the surfaces in patches. I was favoured with this from the neighbourhood of Durham, by the Rev; John Harriman. i keer: ie os ene hy ¢ A P ie Ee ee a Apt 8082 ublithed ly- Ja! Sowerby, London. TAB. XX, Upper and Middle Figure, SODA muriata. Muriate of Soda, or Common Salt, Class 1. Inflammables. | Ord. 2. Mixed. Gen. 4. Soda. Spec. 2. Muriate of Soda, Div. 1. Crystallized. Gen. CHar. Soda in combination. Spec. CHar. Soda combined with muriatic acid. Syn. Common salt. ‘ ta Cah Nath 29 Ty SOP Trove 1803 Bublifhed by-Ja® Sowerby London TAB, XXIX. FERRUM sulphureum. Sulphuret of Iron. Pyrites. Class 3. Metals. Order 1. Homogeneous. Gen. 7. Iron. Spec. 5. Sulphuret of Iron. Div. 1. Crystallized. Syn. Martial pyrites. Kirw. v. 2. 76. ' Pyrites martiales. Marcassites. De Lisle, v. 3. 208. Schwefel kies. Emmerl. v. 2. 289. Fer sulfuré. Hay, v. 4. 65. ‘Tue upper figure is from Cornwall, : This substance is very universal, and not rarely occurs crystallized. It is perhaps as often found in the cubic or primitive form as any thing we know of, especially among: the schistose rocks in Wales, Scotland, Cornwall, and Ire- Jand, on what Dr. Babington denominates Calp, vulgarly called Irish Diamonds. This sort was used formerly for making buttons, and was in fashion as jewellery for ladies’ ornaments about half a century ago, being cut and polished by the lapidaries for that purpose, often to the destruction of the natural crystal. Itis often found among coals, &c. 68 ft forms many varieties of crystallizations. The upper figure shows a group of cubes : the larger one appears some- what laminated in the structure, and is nearly covered as it were with a thin case. They are often quite smooth, but are more frequently found with straight lines or strize on the faces, alternating’ with the faces next to each other, but agreeing with the opposite sides or faces. The cubes are often larger than those here figured. | Under the blowpipe the odour of sulphur is very sen- sible, and a magnetical oxide of irom 1s to be produced. It scintillates with steel. 7 The lower figure from Redruth, m Cornwall, with little cubes, piled like clubs, and somewhat varying in colour, perhaps contains a little more copper. Mr. Kirwan says a small portion of copper is always present in pyrites. The upper part being paler than the lower is a sort of indication ef its holding most iron. Spee. Grav. 4,1006—4,7491. FO lerel 1803 Publfleed by- Ju> Sowerby. London TAB. XXX. FERRUM sulphureum. Sulphuret of ron. Pyrites. Class 3. Metals. Order 1. Homogeneous. Gen. 7. Iron. Spec. 5. Sulphuret of Iron, Div. 1. Crystallized. Spec, Cuar, Sulphur combined with Iron, ‘Turse crystals were communicated by the Rev. H. Davies, from Parys Mine, Anglesea, where there is great abundance in some places, heaped together like grains of sand, so small that their lustre is lost in their minuteness, much less can the cubic form be seen without a magnifying glass. The rocks of limestone, and those passing to re- gular slate, contain them of different sizes. The upper Jjigure is from a specimen the gangue of which is between common limestone and slate, and contains no small quan- tity of the crystals. The gangue is in the more chalky parts stained a little green, perhaps from some oxide of copper. The lowér figure is a piece of undulated (other- wise common blue) slate, which is a durable sort if free from pyrites, as the common air decomposes the pyrites, decays the iron, and the slate becomes rotten. This will be further explained when we are treating of the best slate of Wales, Westmoreland, Yorkshire, Cornwall, &c. et. ISODFublijhed by Ta-"Sowerby, London. ; TAB. XXXT. CUPRU M arseniatum. Arseniate of Copper. SE Class 3. Metals. Order 1. Homogeneous. Gen. 4. Copper. Spec. 9. Arseniate of Copper. Div. 1. Crystallized. Spec. Cuar. Arsenic acid combined with copper. : Syn. Philos. Trans. for 1801, p. 169. hie eee We are obliged to Mr. Chenevix and Count Bournon for the best account of the arseniates of copper. They are found at Huel Gorland mine in Cornwall. The simplest variety, according to Count Bournon, is the obtuse octa- édron. He observes that this octaédron has, in each of its pyramids, two opposite planes more inclined than the other two; which gives a parallelogrammic form to their come mon base. The two planes which are most inclined meet at the apex of each of the pyramids, in an angle of 130°, : and at the common base in one of 50°. The two planes which are less inclined meet at the apex in anangle of 115°, and at the base in one of 65°. 72 The faces are sometimes smooth, mostly bright, and ac= casionally show signs of the angles of the tetraédron, or have striz parallel to their edges, as Count Bournon ob- serves. He also remarks that the four planes terminate in one and the same point; but more commonly the apex is - formed into a ridge, the octaédron being lengthened pa- rallel to the lesser inclined planes. The base is then a square, or at least approaches nearly to that form. The first Jjigure seems to be rare; those with the ridge are more com< mon, particularly such as are further lengthened, passing from the right hand figure in my Plate to the left*. The gangue is an ochraceous quartz with some copper, and often approaches what is called pitch copper: the right hand ‘cure has a little green globule of a waxy appearance. Such are sometimes abundantly scattered over the octaédral erystals, and appear to be carbonate of copper, or malachite. It is either of a beautiful deepish azure blue with a greenish cast, exactly resembling pure Roman vitriol, or artificial sulphate of copper somewhat opaque, or of a fine green ; in which last case it resembles the emerald. Such specimens are most transparent, and vary in being some- times lighter coloured. These are frequently blue within, * The Count mentions these as the only two varieties he has observed in the form of the crystals of this species, although he had opportunity of exa- mining a great number of specimens. I am happy to add a new, and I think interesting, variety, especially as it seems, from what has been said above, to be very rare. See tab. 32. 7S as the fracture readily shows. We.shall now consider the present specimens chemically, with the assistance of Mr, Phenevis, who, as well as Count Bournon, remarks the rarity of this substance in any other country; and it ap- pears that Mr. Hatiy had only seen the hexaédral va- riety of arseniate of copper from Cornwall, in the hands of a friend, when he was about his very ingenious work on crystallography. We therefore may safely conclude that the present and first species of Count Bournon, with all the others, are described in the Philosophical Transactions only, or in works copied from thence. | We shall, however, ex- hibit some varieties not yet described, one of which may be seen in the next plate. That able chemist Mr. Chenevix, having favoured the public with the analysis, found it to contain Oxide of copper........ 49. INTSEMIC ACI. sc c c . V 5, 4 =) a ae ame Biase: sha TAB. XXXIL CUPRUM arseniatum. - Arseniate of Copper. Class 3. Metals, Order 1. Homogeneous. Gen. 4. Copper. Spec. 9. Arseniate of Copper. Div. 1. Crystallized. Far. The solid angles of the mutual base of the two pyramids truncated; Spec. CHAR. Arsenic acid combined with copper. Syn. Phil. Trans. for 1801, p. 169. Tus being, I suppose, a scarce variety, not having been mentioned by the experienced Count Bournon, I am happy to give a figure of it to the public. Among the clusters of grass-green crystals of arseniate of copper, we mostly find some with the corner of the mutual base of the pyramids more or less rounded. These in the present specimen form recular facets, making it a twelve-sided crystal. The facets » pass the common base at right angles, cutting off the four corners: thus the mutual base is an octaédral plane, at right angles with the four corners of the double pyramids. They are somewhat uneven, and show evident signs of the want of a few molecules to fill up their interstices. The crystals in general seem to have been disturbed or in- terrupted, and show markings on their surfaces. Besides this, I have a variety with the sides of the mutual base somewhat rounding, though scarcely perceptible, which is figured in the left hand outline. The broken crystal in the middle, to show the blue within, was most conspicuously so, and is figured of its natural size, beg Jarger than usual ; the other two are slightly magnified. We have since met with one five-eighths of an inch long. 32 Jere 1. 1803 Fblfhed ty- Ta? Sowerby: London. si Sivl. 1803, Pubhifhed by Ja? Sowerby, Londen. 33 TAB. XXXII. CALX carbonata, var. metastatica. Carbonate of Lime, var. metastatic. Class 2, Earths. Order 1. Homogeneous. Gen.1. Lime. Spee. 2. Carbonate of Lime. Dw. 1. Crystallized. Var. Metastatic. Syn. Dent de cochon. De Lisle, tab. 1. p. 530. 2 Chaux carbonatée metastatique. D Hauy, v. 2. le p. 134. Tuts form or variety of crystallization of carbonate of lime is perhaps one of the most common, and has ob- © tained the name of Dog’s tooth spar in England, and that of Dent de cochon, or Swine’s tooth, in France. This crystallization is prevalent of different sizes, colours, &c., in Derbyshire, some affording good examples of the pri- mitive rhomb, being clear, and differing very little from the true Iceland, crystal, which is reckoned the most pellucid, _ and for a figure of which see our tal. 2.. The left hand lower figure shows the usual construction, the edges of the opposite pyramids meeting on the edges of the primitive thomb, when the obtuse ends are opposite to each apex *, the more acute angles forming three principal ones, and the obtuse three less distinct ones: thus each pyramid has six sides, the acute and obtuse meeting in alternate order at the * The metastatic.is formed by an addition of Jaminz, formed of rhom- boidal molecules upon the faces of the primitive rhomb, each plate decreasing 3n width twice its thickness, This will be more fully explained hereafter. 76 common base. The right hand figure represents two pyra~ mids of the same, transversely cut through the- middle, showing a plane of 12 sides, and turned on the axis till they meet each other in an opposite direction, exhibiting a re- markable appearance, called by some authors macling. They often seem to be two crystals passing into each other, and are then said to be twins. This is formed on a ganeue or Jump of manganese, or black wad as the miners term it, which seems to give the crystals a dirty tinge, especially those nearest to it. We do not know that it has any other effect on the crystallization. TAB. XXXIV. CALX carbonata, var. metastatica. Carbonate of Lime, var. metastatic, Class 2. Earths. Order 1. Homogeneous. Gen. 1. Lime. ‘Spec. 2. Carbonate of Lime. Div. 1. Crystallized. Var. Crystal metastatic terminating with primitive facets. Ubprrr Ficures. The metastatic crystallization is. form- ed, as before observed, by a particular arrangement of the molecules. These continue to form regularly, according to the supply of those molecules, which, stopping abruptly, terminate in the obtuse point of the primitive crystal, show- ing three faces. This termination is not very common : the outline on the left hand will help to explain it,.: Tie other lateral faces will be spoken of hereafter. The lower figure shows the equiaxe termination, and the right hand geometrical figure, its formation upon the rhomb. — Suby 1 1802 Fublifred by Ja? Sowerby, London. 54 Aug! 2 1803 Pubiifhed by Ta” Sawurky Sinden TAB. XXXV. CALX carbonata, var. metastatica. Carbonate of Lime, var. metastatic. Class 2. Earths. Order 1. Homogeneous. Gen, 1. Lime. Spec. 2.. Carbonate of lime. Div. 1. Crystallized. Var. Metastatic terminating with equiaxed and other faces. EH "Tus fine yellowish crystal shows at the apex three po- lished faces, which are parts of the equiaxed crystals: se- - yeral others next to them show the approach to the primi- tive rhomb, and three primitive faces; the rest is part of an unequal-sided or flattish metastatic. The double re- fraction is seen, when held in certain directions, by the prismatic tints, which are very beautiful, and in some posi- tions catch the rays of light, so as to show them in great abundance in the numerous flaws; which flaws would be some detriment to the specimen, if this appearance did not so well compensate for them. They also serve by their. direction to show how the fragments are obtained which exhibit the nuclei, See tal. 2, TAB. XXXVI. CALX carbonata, var. metastatica. Carbonate of Lime, var. metastatic. Class 2. Earths. Order 1. Homogeneous. Gen. 1. Lime. Spec. 1. Carbonate of Lime. Dw. 1. Crystallized. Var. Crystal metastatic. pamniddlisic bole Tuts specimen shows a variety of faces depending on cer- tain laws of increase and decrease, and seems more regu- larly forming the metastatic within, where it abounds with pyrites, than externally. This serves to show that crystal- lization may continue while one substance has another within it. The pyrites, from their colour, as well as form, - should seem to hold copper as well as iron. AugL 1803, Publifhed By Ja! Sowerby, London duc! I 1803. Publijked by Ja © yaverhy. London CB. en VU CUPRUM. arseniatum: | Arseniate of Copper. Class 3. Metals. Order 1. Homogeneous. Gen. 4. Copper. Spec. Q. Arseniate of Copper. Dw. 1. Crystallized. Var. Crystal an hexaédral plate with inclined edges. Syn. Cuivre arseniat€é lamelliforme. Haiiy, v. 3. p- 578. Arseniate of copper in hexaédral laminze, with in- clined sides. Phil. Trans. 1801, p. 176. Tuis beautiful variety is described by Count Bournon in the Philosophical Transactions for 1801, and we cannot do better than profit by his description. ‘It is in very thin hexaédral laminz, the six sides alternating in an inclined position, with the broad hexaédral planes on either side at an angle of about 135°, and the third at 115°, on the op- posite side.’ See fig. 1. The crystals are more or less piled on each other, and are often to be divided, or split parallel to their surfaces, in the same manner as Mica. They are very brittle, mostly of an emerald green, and as transparent as the best glass, their lustre resembling the thin glass called 80 frosting ; or, as the Count expresses it, the lustre of thosé coloured metal plates known by the name of foil, and are most splendid when the light falls on the broad planes. The edges are more opaque, partly from the contrary direction of the crystal, and partly from the strie in the direction of the lamine. Fig. 2. is a general group of crystals. Fig. 3. shows a variety in my possession of a yellower tint *. The lower geometrical figures show, according to Count -Bournon’s measurement; that if the inclined sides were to be increased by a regular set of decreasing plates placed upon the surface till they formed an equilateral triangle, they would become oblique octaédrons, (see right hand fgure;) and if they further continued on these planes till they were lost, they would produce a rhomboidal prism, which, as it seems to agree with the fragments, may be the primitive form. I should have observed that it not only splits into lamine on the broad planes, but that it also rea- dily does so with the side facets. Its fracture is sometimes irregularly conchoidal and glassy. Spec. grav. 2,548. Mr. Chenevix found it to contain oxide of copper 58, arsenic acid 21, water 21. * These two are somewhat magnified. ipa) Ss rl Be Le Ly mer mE ae: 4 e es Londor Ta * Sowerby b Fubhjhed TAB. XXXVI. CALX carbonata feetida. Botryoidal Limestone with a fetid smell. Class 2. Earths. Order 1. Homogeneous. Gen. 1. Lime. — Spec. 2. Carbonate of Lime. Div. 2. Imitative. Var. Botryoidal. Syn. Swine Stone. Kirw. v. 1. 89. Stinkstein. Emmerl. v. 1. p. 487. Chaux carbonatée fétide. Hatiy, v. 2. p. 188. We have exhibited the present specimen of limestone as a very curious one, on account of its resembling-a bunch of grapes. It seems to be formed by water passing through loose marly earth, and consists of smaller or larger globules, according to circumstances; sometimes in bundles resembling Ketton Stone, (see pl. 8, upper figure,) at other times much larger (see the lower figure in this plate). The globules are occasionally a little hollow, and crystallized within; sometimes nearly clear, and white, when they are destitute of smell; but they are more commonly solid and brown within, have a very foetid* odour, easily perceived by scraping or pounding. This smell has been ascribed to * The fetid variety of Limestone is by no means rare. ae 52 bitumen, but is of a very different nature. Vauquelin con- siders it as sulphurated hydrogen. The colour is caused by oxide of iron with more or less clay. The odour goes off from the surface if exposed to the atmosphere; which makes it necessary to scrape it: the heat used in burning it to lime dissipates it entirely. The lower figure is very interesting, as it shows the stra- tification while crystallizing, the darker parts making it evident. The top of this specimen is crystallized with the acute ends of the inverse rhomb, (see tab. 4. upper figure.) pointing outwards, which is not unusual in this kind of concentric construction of calcareous earths. Lady Wilson first gave me specimens of this stone, from Sunderland in the county of Durham. Mr. Winch, F. L. S. has since fa¥ voured me with many varieties of it from the same place. The Rev. John Harriman sent me a specimen from Hartle- pool in the same county; and it should seem by his obser- vations that this curious stratum may extend from Hartle- pool to Sunderland, all along the coast, and perhaps much further. It is called Building Hill Stone in Sunderland. pores i oY on ; | i q \ 40 Leto rt ~ Sowerhs Ta by Z. 2803, Lubbithed Jesr. AA WOOD Geandw kat: SILEX arenacea. Siliceous Sandstone. Class 2, Earths. Ord. 3. Aggregated. Gen. 6. Silex. Spec. 2. Grains of Silex more or less agglutinated, Div. 3. Amorphous. Spec. Cuar. Fracture granular. Syn. Siliceous sandstones. Kirw. v.1. 364. Cos friabilis. Linn. Syst. v. 3. p. 63. 9. —- coagmentata. Linn. Syst. v. 3. p. 63. 10. Quartz arenacée agglutinée, ou Grés. Haiiy, v. 4. 464, SanDsToNEs may be said to be composed chiefly of quartz in smaller or larger particles, which, according to Kirwan, should not exceed one third of an inch in diameter. In the representation of such as are not primitive sandstones, it is thought of much utility to put those which have impres- sions on their surfaces of plants, shells, or other things for- merly organized, that while we acquire a common idea of the substance, it may help geological purposes, which will be found extremely essential in mineralogy, as it leads to the sera of formation of different strata, distinguishing by such helps the more recent from the most remote. 5+ TAB. XXXIX. THE upper figure 1s chiefly composed of irregular whitish grains of quartz, cemented to each other by a sort of agglu- tination ofits own particles, and in some parts with oxide of . iron, which gives it the brownish tinge: it has a few specks of mica, and a very little decomposed feltspar. This was sent me by the Rev. Mr. Harriman from Durham. The lower figure is perhaps the coarsest sort of sandstone, of much the same ingredients, but of a looser texture, with more decomposed feltspar, and was given me by Lady Wil- son, who brought it from Walmington in Cumberland. The coarseness of the stone shows plainly that it could not have been formed by human contrivance with the present beautiful ornament, but that it is a natural production, which equals in simplicity and elegance some of the most admired ornaments of antiquity, and may, like them, give an useful hint to modern architects. The impressions seem to be like the leafy scales of the stem of some plant yet unknown to us. They are most like some foreign Euphorbia or Cactus. TAB. XL. Tue lower figures in this plate are of the finest texture; the particles in the right hand figure are so fine as scarcely to be discerned without a magnifying glass: the fracture, which is a little shattery as well as earthy, in some parts readily shows the sand-like texture. It is more strongly 4 85 cemented in other parts by means of a very little lime, and more strongly still by a siliceous cement. The original of the impression we do not at present know. The particles in the left hand figure are somewhat larger, but are more compactly agglutinated by the siliceous cement, and seem as if more or less fused ito each other, somewhat ap- proaching the vitreous appearance. The impression seems to belong to some vegetable, possibly furnished with spines in the order where the little ovate knobs appear, which in a specimen lent me by Sir Joseph Banks were rounder, his whole specimen not being compressed *, The upper figure with the long-squame is what is called by Kirwan ferru- ginous Sandstone, see v. 1. p. 365. Itis coloured with an ; oxide of iron, which seems ‘to be in that state of oxygeniza- tion on the outside, which has the -conglutinating power ascribed to it by Mr. Kirwan, and is consequently more compact on the outside than on the inside. Pebble stones held together in this manner are very common in gravelly places about London. The right hand upper figure is a coarser stone of a similar nature, with some pebbles occasionally here and there about it; also some lumps of a caalky appearance resembling de- composing feltspar, if I may guess by the little remains of the crystal and fracture. Thus it is perhaps next in order * I have figured the specimen given me by Mr. Martin of Derbyshire, as it had an impression on it resembling a bamboo stalk, although Sir Joseph Banks's was better in other respects. 86 to the Rubble Stone of Kirw. v. 1. 366. Sandstones are found in many parts of England, and are of great use. They are natural filters in the laboratory of nature, and are now become a modern branch of traffic in Derbyshire, London, and other places, for filtering water. They are brought from Newcastle for grindstones, sharpening of scythes, rubbing down copperplates, &c. Some sorts have been used for buildings, as at Windsor Castle, which is chiefly of the whiter kind and fine grained. The grey and black blotches will be explained hereafter. Mr. Martyn above mentioned has given figures of seyeral specimens of these in his Derbyshire Petrifactions. sep?) 1804, Publijhed by Ta" Sowerky, London Bola 6 palace! Dy 1! SILEX quartzum primitivum. Primitive crystallized Quartz. Class 2. Earths. Order 1. Homogeneous. Gen. 6. Silex. | Spec. 1. Quartz. Dw.1. Crystallized. Var. 1. Primitive. Gen. CHar. Rough and harsh to the touch. So- luble in the_two fixed alkalis; but in no acid but _ the fluoric, except (as some think) when in com- bination with an alkali, much diluted with water; also soluble in 1000 times its weight of water. Spec. CHar, Nearly uncombined. Burns to. an opaque white. Spec. grav. 2.64 to 2.67. Kirw. Hay says that the primitive crystal of Quartz is the slightly obtuse rhomb, measuring 94° 40’ and 85° 56’. He does not seem to have met with a specimen. Mine, which is formed in a variegated flint, from Lewisham in Kent, showing only one end of the rhomb, agrees with this de- scription, as the primitive: some of them show signs of the other three faces, approaching the double hexaédral py- . ramids. See the left hand figure. . Silica when transparent and crystallized is commonly called Quartz, Rock Crystal, or Mountain Crystal; the purest: are generally colourless, and often very brilliant. They were 85. formerly much esteemed, and known by the jewellers under the name of Rock Crystals, and Scotch, Welch, or Cornish Diamonds; nor do jewellers seem to distinguish between Rock Crystal and Quartz, although they chiefly use Rock Crystal. It is sometimes found yellowish, or of a topaz colour, passing to red, purplish, brown, black, &c. Its lustre is glassy ; it is more or less transparent, and is said by most authors to have a double refraction: we, however, could not discover this circumstance. The fracture is coarse, splintery, conchoidal, or undulating, the flaws frequently iridescent. Hardness 10. Kirw. brittle, strikes fire with steel, and scratches glass. It is the chief ingredient in making glass, when fused with potash, soda, &c. and seems to be only a purer kind of flint. Diamond has generally been classed as the first species of Silex, but it has at length been discovered to be the purest species of Carbon. Quartz seems very properly distinguished from rock crystal by Mr. Kirwan. The former if exposed to a strong red heat be- comes of an opaque white: this specimen is therefore truly quartz, as I have proved by trying a fragment, which being exposed to astrong heat in a common fire became first of an opaque white, and by longer exposure somewhat opaline, or rather like chalcedony; not unlike common flint under similar circumstances. Rock crystals on the contrary, ori- ginally dark brown, &c. by the same heat become beauti- fully transparent, as some lapidaries and jewellers well know. oa Sept 2 1808. Publfhed be Ja* So ty) wer London TAB. XLII. SILEX quartzum. var. dodecaédrum. Crystallized dodecaédral Quartz. | EEE Class 2. Earths. Order 1. Homogeneous. | Gen. 6. Silex. Spec. 1. Quartz. Div. Crystallized. Var. Dodecaédron with triangular faces. Syn. Quartz. Bab. 80. : Quartz-hyalin dodecaédre. Be Haily, tab. 40. sien ; | Cristal de roche dodecatdre. De Lisle, t. 2. p- 10. Eee ep VCO Tue regular dodecaédral crystal of quartz 1s somewhat rare. I at present know of no certain habitat for it in Great Britain, excepting at Craig Lackart, about 3 miles from Edinburgh, from whence I have an irregular group given me by Dr. P. Murray, who gathered it himself. It is evidently taken from a rock externally in a state of de- composition, as its matrix is porous and mixed with red oxide of iron. It is sometimes found at Bristol, and also on the Lancashire iron ore or hematites, Bal. 80. I have such specimens also on an iron ore from Devonshire. The specimen here figured, I believe, is from Cader Idris in North Wales, and seems to have been thrown off from the 90 main rock by an ochraceous decomposition: on that side towards the rock it is extremely porous, not unaptly resem- bling French burr, which is used for mill stones. Quartz or silex is not only common in our primitive mountains, but also in our gravel roads. It frequently takes place of animal and vegetable substances, forming petrifactions, or running, like lava or wax, into a mould, occasionally passing into the state of chalcedony, cachalon, &c. Frag- ments of this specimen became opaque in burning, as did that from Scotland. Crystals of specimens nearly dode- eaédral on Lancashire and Bristol iron ore are properly rock or mountain crystal, as they burn transparent, Sept LEO3 Publifhed tr Ta * Sowerby-Londou TAB. XLII. SILEX granatus. Garnet... * Class 2. Earths. Order 1. Homogeneous. Gen. 6. Silex. Spec. 13? Garnet. Div. 1. Crystallized. | Var. 1. dodecaédral, or primitive. Spec. CuHar. Primitive form, the rhomboidal dode- caédron; scratches quartz. Syn. Garnet. Kirw. 1. 258. Granat. Emmerl. 1.43, and 3. 246. Borax granatus. Linn. Syst. ed. 13. v. 4. p. 96. Grenat. Haiiy, 2. 540. Garnets are of different degrees of hardness. The Ori- ental and Behemian ones are of a brighter colour, and are yauch harder than the British, but all want the aid of the lapidary by thinning them, to show their lustre, and when set by the jewellers are always placed upon a foil. They were much esteemed for hoop-rings, ear-rings, &c. about 40 years ago. The British garnets are commonly much the softest, and not valued by the lapidaries. They are chiefly found inclosed in micaceous and granite rocks, though some- times otherwise. Besides the other ingredients spoken of in garnets, the British ones frequently hold particles of mica, and are of aless firm texture. We, however, have the satisfaction to find them present most of the different forms of crystal- 92 lization. We here give a representation of what is reckoned the primitive crystal, (viz.) the rhomboidal dodecaédron. These are found in great plenty in the Plum-pudding rocks, as they are called, at Huntly in Scotland. We have bought specimens at sales which are said to come from Bohemia, seemingly of the same sort, and in the same gangue as those from Huntly. The Syrian garnet is of a more scarlet hue, though I have some cut ones, said to come from Scotland, nearly of the same colour, but rather less bright. - The lower figures are from rocks near the same place in a lighter-coloured gangue (a granite), with the edges of the dodecaédron forming 24 narrow hexaédral facets, in addi- tion to the 12 rhomboidal faces. I have the same sort of garnet, though lighter, in a basaltic stone, and in greenish — hornstone from Scotland, Mr. Jameson has found them in micaceous schistus, v. 1. 219. v. 2.212. External lustre casual, internal 2.3.1. of the brownish and blackish fre- quently 0. Kirw. Fracture of the hard ones somewhat flinty or conchoidal. Mr. Kirwan calls the oriental garnets carbuncles, p. 258. TAB. XLIV. SHOWS a variety in a lighter granite gangue with the edges more deeply truncated on the 6 opposite edges, see the right hand and middle figure, making an 18-sided cry- | stal. The left hand figure shows the truncation equally deep of a 36-sided figure. The lower figure forms a prism by 6 sides being elongated. These varieties are more or less distinct in the gangue above. Sep? 1 1803 Fublifned by Sa” Sowerby London Oct! 1. 1803. Published Tus Sowerby, London: 45 ne TAB. XLV. CUPRUM arseniatum, var. amianthiformis. Amianthiform Arseniate of Copper. EE / Class 3. Metals. Order 1. Homogeneous. Gen. 4. Copper. Spec. Arseniate of Copper. Div. 2. Imitative. Var. 2. Amianthiferm. Spec. CHar. Copper combined with arsenic acid. Syn. Amianthiform arseniate of copper. Bournon, Phil. Trans. 1801. p. 180. N. 2. 4th species, &c. Chenevix, Phil. Trans. 1801, p. 199. ‘Turs species of copper appears first to have been described _by Count Bournon. The present variety is a curious ex- ample, and seems so well described by the above author, that we shall transcribe part of his own words. ‘ This variety is composed of fibres as delicate as those of ami- anthus, of the flexibility of which they frequently possess a certain degree.” In the present specimen they resemble the finest filaments of silk. It seryes to show a variety in colour not mentioned by Count Bournon, viz. the purple hue, which more or less covers the surfaces or the points of the flexible threads. The other parts are of a lightish straw yellow. Its resemblance to a raceme of currants or a bunch 04 of grapes made me think that each bundle was composed of fibres formed from its centre (as some of the smaller ones are): but on opening some of them we found an ochraceous gravelly substance in the middle, from which they diverged more or less regularly, often more dense and hard inwardly than outwardly. The more regular ones are commonly more white and satiny than the others, excepting towards the tips, and are more of the texture of rotten wood. The outsides are very tender, and easily bruised. According to the analysis of Mr. Chenevix, this species contains Oxide of copper........ 54 Ansenic acid “PEs. . He . 30 WATE Scie eres oon ee 16 100 Haiiy mentions capillary arseniate of copper, v. 3. p. 578. and observes “that foreign mineralogists have found different regular forms of arseniate of copper, which from certain cir- cumstances he has not yet been able to determine.” The lower magnified figure shows some of the fibres or filaments. of both sorts here mentioned, some of which are collapsing at their points as if they had been wetted, forming various reticulations and indentations of a purplish hue, apparently retaining that colour from being less exposed to rubbing or any other accident. This was found in Huel Gorland mine in Cornwall, from whence most of the other arseniates of copper come. ee 46 Oct! 1. 1802. Publ hed by Jar Sowerby, Londow. 95 TAB. XLVI: THE upper specimen is nearly of a straw colour, and di- verges in a stellated manner from a common centre, with a good deal of the appearance of that kind of rotten wood called Touchwood. I have seen specimens of different shades of green, which somewhat resemble the Byssus-like carbonate of copper, see the surface of the lower figure, where there are also the various colours from straw to dark brown, some of which appear of the colour of darkish brown rotten wood, a little resembling the wood Tin Ore of Cornwall, but may be readily known from it by being so much less heavy than that ore. This appearance occa- sioned the common denomination of Wood Copper, before Count Bournon’s paper aboye alluded to was published. “yt SBN 2 2S a Le = “kh 7 1603. Publifhed by Ja: Sowerby, Londor. an TAB. XLVII. CUPRUM carbonatum, var. byssoides. Byssus-like Carbonate of Copper. Class 3. Metals. Order 1. Homogeneous. Gen. 4. Copper, Spec. 3. Carbonate of Copper. Div. 2. Imitative. Var. 8. Byssus-like. Spec. Cuar. Copper combined with carbonic acid. Syn. Green Malachite. Rashleigh, fasc. 1. tab. 7. fh Gs Cuivre Cabonatée vert soyeuse. Haiiy 3. 573. Malachit. Zimmerl. ¢. 2. p. 253. EE Macacurre Copper ore of this beautiful Byssus-like ap- pearance has been found in great abundance at Llandidno, in Denbighshire. It has rather the appearance of a vegetable than a mineral production, and is most commonly found of a beautiful velvety appearance. The upper surface is extreme- ly tender, and bruises on the slightest touch, assuming a whitish appearance. The sides become more or less white on exposure to the air, and when fresh broken, are of a satiny green, formed of fine thready radii, often closely compacted in stratified order, one coat over another, rightly H 98 compared by Mr. Rashleigh to the coating of an onion. Itis found from a light to a dark green ; the surface is some- times tinged with, and passing into a red, or crimson. Its form is generally in protuberating knobs or mammille. Mala- chites, though well known in many parts of England, have been generally esteemed foreign productions: Dr. Babing- ton, however, mentions the harder sort, resembling the foreion, being found at Helstone, and the Land’s End in Cornwall, in the South of Wales and Yorkshire. We have it from Wheal Unity, and many parts of Corn- wall. The softer sort is not unfrequent among copper - ores, with the other which we have from North Wales, as before mentioned ; and our friend, Dr. Ridout, was so good as to give us a specimen which he gathered himself at Dod- dington mine, in Somersetshire. They are said to contain from 66 to 75 per cent. copper, 19°4 carbonic acid, and 5°6 water, and sometimes a little arsenic. Hardness, 5-7. Kirw. Spec. Grav. 3°5 to 3°994. 48 AWB. XUV. CARBO bituminosus. Pit-Coal. Class 1. Combustibles. Order 2. Mixed. Gen. 6.. Carbon. Spec. 1. Bituminous. Spec. Car. Bituminous oxide of carbon, and oxide of carbon; mixed. Syn. Mineral Carbon impregnated with bitumen. Kirw. 2. 51. Bitumen Lithanthrax*. Linn. Syst. Nat. ed. 13. 28! pre WIT ; Steinkhole. Emmerl. 1. 60. Houille. Hay 3. 316. De Lisle 2. 590. Coat is a curious, valuable, and well-known article in Great Britain, supplying us with great store of excellent fuel. There are many varieties in different mines, and even inthe same mine. The upper figure is taken from a com- mon Newcastle specimen, from whence a great part of * Linnzus included all coals under this title, describing them as schistose, which does not include all the species, 106 England, and many parts of the Continent, are supplied. It is evidently composed of two sorts of strata, to external appearance sufficiently distinct. The one apparently the remains of wood in a charred state, like charcoal or oxide of carbon. This has hitherto escaped the notice of most authors: besides the grain and appearance of wood, com- mon in this and most other coals, it will be known by being the only part in coal that soils the fingers. If separated, it burns like charred wood, leaving a similar residuum *; it is also soft and powdery, like burnt wood ; breaks in a crumbling manner, and falls into small particles +. The other part is more compact, shining, and brittle, easily scratched with aknife. The least touch of the finger hurts its polish. It has a somewhat splintery conchoidal fracture, and seems chiefly carbon mixed with bitumen. It inflames in a moderate heat, yields much smoke, bubbles, and'melts something like pitch, and helps the binding or caking, as it is called, {which is the sign of a good coal, at least for housekeeping) and leaves a cinder which lasts a great while, giving a strong heat. The small remains from a common fire are still valuable on that account for the forge. If burnt long’ in a violent draught of air, it forms a clinker of no value; ® We have reason to believe that it contains no alkali. + Mr. Jameson says, “ this does not seem a common appearance,” when he found “ carbonized wood which could not be distinguished from carbonized Fir.” v. 2. p. 87. It is probably the smut of Mr. Kirwan. TOL which shows it to contain some silex, and, perhaps, iron. Coals are not known to crystallize, yet this glossy part in many has a regular disposition towards it in the partings ; and these mostly have the same angles, forming an upright prism with rhomboidal bases, the angles of which are about 84° and 96° *. The middle figure in this plate is a frarment of the New- castle coal; the completest crystal-like appearance I ever saw. The upper surface is charcoaly, and it rests on a si- milar substance, with irregular strata beneath. Newcastle coal loses about 35 per cent. of its weight while flaming. Linnzeus’s description seems to belong to the more slaty kind. The lower figure is from a piece of Scotch coal, which was broke through the bituminous strata, in a transverse direction: and shows the glossy fracture, with a sattiny ap- pearance, as well as the angles of partings. This bitumi- nous stratum is commonly somewhat shaly in thus sort of coal: the other part is mostly pure charcoal, and often ex- hibits the shape of branches compressed, and the same transverse contractions which take place in charring or burning common deal. This coal loses 25 per cent. while flaming, which it readily does, and continues its heat with * Most mixed coals in the common large masses break through the whole stratum more or less in this form: these breaks or cracks are called backs, cutters, and partings, by the miners. 102 “very little bubbling ; flaking and falling to pieces in a slaty form, leaving a whitish ash. Mr. Kirwan describes Scotch coal from Irwine as “ hay- ing layers in contrary directions, and being hence often called Ribband Coal. Lustre of the alternate layers 3, 2, (silky and brighter.) Fracture small grained, and coarse grained, curved, foliated. Hardness 4 to 5. Spec. Grav. 1°259. Its composition I have not examined.” Mr. Kirwan’s description is very good, but, for the most part, will agree with any stratified coal, viz. the New- castle, Chesterfield, Staffordshire, &c. But this we need not wonder at, from his not having examined the. compo- nent parts. I have a coal from Boroughstoneness, given me by Dr. P. Murray, of the kind above described, and some said to be passing into splint, varieties of which are found at New- castle, Wiggan, and other places. These are often con- founded with the Box Coal or Cannel Coal of Kirwan, v. 2. p. 52, the true sort, which is now very scarces Of these we shall give a fuller account hereafter. We were favoured by Mr. E. D. Clarke of Jesus lhe Cambridge, in February 1804, with specimens of Lynn Coal, presenting pentaédral prisms, which he has observed in it for more than a year past. Other coals present this figure, and also trihedral prisms. These are produced by a fracture parallel to one of the diagonals of the base of the -tetraédral prism. 49 a TAB. XLIX. CARBO oxygenizatus. Oxygenized Carbon. Class 1. Combustibles. Ord. 1. Homogeneous. Gen. 6. Carbon. Spec. 2. Oxygenized Carbon. Gen. Cuar. Hardest of all known substances. Spec. Cuar. Carbon combined with such a propor tion of oxygen as to remain ina solid state, mostly opaque black. Syn. Native Mineral Carbon. Kirw. 2. 49*. We find Mr. Kirwan’s description of Native Mineral Car- bon *, Blende-Khole + of Werner, so well agrees with the Denbigh coal, that the chief part of his expressions may with great propriety be made use of. His specimen, he ob- serves, 1s the purest known, and came from Florence; it depends much upon the choice of specimens to cull the ‘purest ; and in the same mine many varieties may be found. * When Mr. Kirwan wrote this, common charcoal was thought to be pure carbon; it is since found to be an oxide of carbon, and that Diamond is the only native mineral carbon known. Mr. Kirwan’s description agrees with oxide of carbon, for which we quote him. - 4 Mr. Jameson calls this Khole-Blend, and observes that it does not stain the fingers. 104 There is little doubt of the Denbigh coal being nearly as pure an oxide of carbon as is likely to be found. © Its colour is black; its lustre from 3 to 4, approaching the metallic. Transparency 0. Hardness 4to 5: brittle: stains the fingers.” It could only be the softer part occasionally found in this coal that stains the fingers; as in that from Swansea, resembling charred wood; dusty and with less lustre than above-described *, and what he denominates Culm coal of Wales; another variety which agrees with what Werner calls Glanz-Khole. Denbigh coal is seldom stratified, and is apt to separate with a reedy structure, or impression, in isregular striz. The cross fracture is often conchoidal and undulating. This fracture and the prismatic hues for which this coal is famous, have naturally gained it the appellation of Peacock coal ; and-it is no less remarkable, that a piece with the colours on it, may be heated red hot many times, and, on cooling _ again, will return to nearly the same appearance, retaining its prismatic hues. We are happy to say Mr. Jameson promises to give a fuller account of his khole-blend, at some early opportu- nity, and has also promised, with his usual generosity, to supply us with specimens. All coals commonly so called produce a black powder. * This, when irregular and loose, as it sometimes is, appears by the de= scription to be the smut of this author. Culm means only smallish coals of inferior value, which do not pay duty. = Sa 50 TABBY I. CARBO oxygenizatus. Oxygenized Carbon. Some of the Swansea coals resemble the Denbigh coals in their structure, and are nearly the same in quality. This wpper figure has the charcoaly and stratified part in various directions. Some parts resemble burnt straw in re- gular rows: others form conical appearances, converging or diverging from a centre. We also find horizontal and oblique strata. The shining part is in various directions, with a confused and shattered appearance. Some of the striated parts were slightly covered with charcoal in fine dust, easily rubbed off, the striated impression still remain- ing in immediate contact with the shining part. In other parts were thick layers of charcoal in irregular strata, but somewhat horizontal to the other parts, the whole having a peculiar, yet confused, appearance. It is very brittle, and easily shattered to pieces. The lower piece is much tougher, and the striz have not a vestige of charcoal about them, nor will they soil the fingers. . This seems altogether more indurated. These two and the Denbigh coal have nearly the same qualities as to their uses. They are difficult to ignite, and burn without flame, remaining a long while, and giving a great heat, without much apparent change ; whence they have been de- nominated Stone Coal. They are used for malting, and for burning lime, and are frequently mixed with such coals 106 _ as will more readily inflame, to assist the burning. They are supposed to contain Jess oxygen with the carbon than other coals, and therefore require the assistance of those which contain more oxygen. It may not be amiss to observe here that diamonds require oxygen to assist their burning, in the proportion of 4 parts to 5 in a strong heat; and in burning they pass into the black state of charcoal, continuing to burn like ity and giving out carbonic acid gas (sce de- scription, Tab. I.*) in the same way, the carbon being aérated by the caloric or matter of heat.. Although dia- mond has always been of high value, and well-known from the earliest ages, yet it was left for Mr. Tennant in the year 1796 to prove it to be a pure carbon. See Phil. Trans. 1797» p. 123. 5 There are other sorts of coals about Swansea, of which we shall speak hereafter. Coals mostly appear to be the combustible remains of vegetation, provided apparently to secure whole forests for the use of after generations. They are mostly formed in the strata of plains, composed of marle, sandstones, and limestones, most of which show the remains of animal and vegetable petrifactions, or im- pressions. See Sandstones, Tab. XL. The blackened parts in those figures are apparently the remains of bituminous carbon, as it were in the last stage of infiltration. * Itis found native in some caverns, wells, and mines, and is called choke damp of the miners. It is often fatal to them. TAB. LI. BITUMEN Gagas. Jet: Class 1. Inflammables. Ord.2. Mixed. Gen. 2. Bitumen. Spec. 1. Bitumen with oxygenized carbon. Spec. Cuar. Bitumen combined with about 30 per cent. of oxygenized carbon. Syn. Jet. Kirw. 2. 64. ) Jais. Daubenton 30. De Born 2. 79. Varieté du Schlakiges erdpech. Emmerl. 2. 50. Jayet. Haity 3. 324. Bitumen Gagas. Linn. Syst. Nat. ed. 13. te Be Bait Tue upper figure represents a curious piece of Jet, remark- able for the remains and impressions of shells about it. It was sent me from Lowestoft by Dr. Smith, President of the Linnean Society, Jet is well known to have been found on the coast at Lowestoft for many years, where amber and curious pebbles are often found. Some fishermen artists of the neighbourhood employ their leisure at convenient seasons to search for them, and form the two first-mentioned into 105 small trinkets. We shall consider true Jet to have passed from the remains of some sort of wood, as the ligneous fibre is in some instances seen; in other specimens it is so condensed and compact as not to be discernible. This substance appears also to be saturated, as it were, with bitumen, insomuch that it readily inflames, losing about 14 grains in 20, with much smoke, and a slight bituminous odour. The remaining cinder, if continued to burn, leaves a very trifling residuum. It is well known to be of the most opaque black (witness the common saying, ‘ black as jet*’’); but it will bear a fine polish. Its surface excited by friction possesses the resinous electricity, which distinguishes it from cannel coal, a substance it very much resembles. It may be scratched by common calcareous spar, and will itself scratch amber and gypsum. The fracture is conchoidal, occasionally re- taining that of wood. Lustre 3 to 4; transparency 0. Spec. Grav. 1-104 to 1°744. Kirw. It has generally been said to swim on water. Thin pieces, indeed, laid lightly on the water, will float for a short space of time; but at length the water passes over them, and they sink: perhaps some slight trial of this kind might cause the common idea of its swimming. Of many pieces in our possession none will éwim. Linnzus called it Bitumen Gagas, from the river Gages in Lycia, near which it was found. The presence of * The streak or powder is always brown, 109 shells, and the impression of the Cornu-Ammonis, indicate its former less indurated state. The lower piece has some signs of incumbent strata hav- ing been on the upper surface, in an obsolete impression, and also some obscure crystals of carbonate of lime under- neath. The fracture is in part largely conchoidal. With some difficulty we may observe the woody stratification. It is truly black. I have a piece where the woody texture is very evident, with small cubic pyrites on one side. With heat and water I decomposed a bit of it, so as very satis- factorily to expose its woody structure. It comes very near to the most indurated Bovey coal and surturbrand *, evi- dently belonging to that division. * These also produce a brown powder. : vs ia i awh ~ ; d F ‘ft! oni TONS 5 baie: Penn avis ud ; i se ; ‘Bilan Wine ee ¢ eos hy VAT tia? 2a i wank ‘Sane ar d gy Rely eer a cea ate att 3 UASN rtd Cae? ae Ta rae ae : ii Bed; ner | : ~ tise ae 1 a i . yar ta 49 c . E % “aiid ne Sea ae wa tt er 4 nq rf y eat it , ep Vaa eh a brie aly besitos gaiabdon Vie ees sent a bux tf 1. & S03 Prblejhed lo- Ja” Sowerby London 32 T Abo LAT: AURUM nativum. Native Gold. Class 3. Metals. Ord. 1. Homogeneous. Gen. 2. Gold. Spec.1. Native. Div. 3. Amorphous. Gen. CHar. Malleable, sonorous, reddish yellow, Spec. Grav. Spec. CHar. Uncombined. Syn. Native gold. Kirw. 2.93. Phil. Trans. 1796. p. 45. Aurum nativum. Waller, t. 2. p. 355. Gediegen gold. Emmerl., t. 2. p. 111. Or natif. Hatiy 3. 374. Aurum nativum. Zinn. Syst. ed. 13. Gop is well known to be found in Peru, several parts of the East Indies, and Hungary, often crystallized in octaé- drons and their modifications. It has also been found in Scotland. We have specimens from Cornwall and Ireland. We received a letter from Dublin, dated Oct. 24th, 1795, which relates some curious facts that may be worth men- 112 tioning here. It is strongly maintained in the antient Irish records, that in the courts of their kings and residences of their great men, an extraordinary magnificence was once displayed. That they feasted and drank out of vessels of gold, used it for armour, ornaments of dress, &c. Inan age when navigation, and therefore commerce, were cir- cumscribed, it is concluded, that the oold must have been found in the country. Those who doubt this judge from the disregard that has been invariably shown by the foreign settlers in this country to its mineral productions. They presume that it could not have escaped their avarice or their skill, if any thing of the kind worth regarding existed here, and they maintain that the gold must have been procured somewhere from abroad. A recent transaction has showa that there is probably much gold in this country not many miles from this city. The people of its neighbourhood have long been acquainted with it, and from time to time sold native gold to the silversmiths, but would not tell where they found it. A late disagreement about the division of their treasure caused a discovery. A stream descending from a mountain * runs along a valley at its foot: in the sand of this stream and the sand of the valley on either side are found lumps of native gold.” Pieces have been found weigh- ing 92 0z.; but they are generally much smaller, from 3. ounces toa few grains. It is said some families were in the * Mount Groghan near Arklow in the county of Wicklow. 113 constant habit of procuring it*. Endeavours have lately been made to discover the mine, but, as far as we yet know, to no purpose. The upper specimen was lent me by Sir J. Banks, who bought it of an Irishman who brought some to London to sell to the curious; and this was one of his largest specimens. It is formed of flattish pieces, or lamellated, as if it had been rolled up and beaten abgut very irregularly, as Sir J. Banks truly remarks, so that it may be called entirely shapeless. It was cut in two at the mint, which helped to discover this foliated appearance; and also, that it contained grains of whitish quartz and an ochraceous gritty clay (see the cut Jigure). A piece of soft lightish schistus, or slate, with a gray appearance on the inside is to be seen in it. The external colour is somewhat redder than where it is broken or eut. Mr. Blackford kindly sent me a piece somewhat paler. The third figure on the right hand was a piece of a redder cast; that on the /eft hand was the whitest of any I have seen from Ireland, These two were purchased for me by my friend Colonel Velley. The three lower pieces are different coloured specimens, from Lammon tin stream, near Falmouth, in Cornwall, * We have been told that lumps of gold of a large size have been till lately used as weights in some of the common shops, and others placed to keep their doors open, in some parts of Ireland, the owners not knowing what they truly were. 114 Gold is much more scarce in Cornwall than in Ireland. The Irish specimen spoken of in Phil. Trans. was found to contain Of ine Gold vo. one Fine Silver Alloy Copper and Iron 03 24 Other specimens differ a little ; and thus, if we may judge by the outer aspect, the reddest probably contains most copper and iron, and the whitest most silver. More silver seems to give agreenish tinge to gold: the little lowest left- hand figure has that tinge. 53 7. TAB. LIT. CUPRUM oxygenizatum, var. octaédrum. Crystallized Red Oxide of Copper, Crystal Octaedral. Class 3. Metals. Ord. 1. Homogeneous. Gen. 4. Copper. Spec. 3. Oxide of Copper. Spec. Car. Copper combined with oxygen. Syn. Red calciform copper ore. Kirw. 2. 135”. Native oxide of copper. Bab. 174. Roth-kupfererz. Emmerl. 2. 213. Cuivre oxydé rouge primitif. Haiiy 3.557. Some of the crystallized red oxides of copper deserve from their lustre the appellation of Ruby Coppers more than others, which will be shown hereafter. The present fine specimen has more of the steel-like lustre, as most of the octaédrons have: however, the beautiful red sparkles in- ternally with much brilliancy. It. is not difficult to scrape it with a knife, and the least scratch produces a rich red powder of the colour of the gum called Dragon’s Blood *. * Known in the Pharmacopeia by the name of Sanguis Draconis, and ex- tracted from Calamus Rotang of Linnzus. 116 The specimens look red most by candle-light. They are found in Wheal Unity, near Redruth, in Cornwall, and in other parts of that county, as well as in different parts of Europe. Foreign specimens, as far as I have seen de- scribed, seem not to be superior in the size or perfection of their crystals to the Cornish ones. The matrix of our upper figure is shattery quartz, supporting native copper, from which the oxide seems to proceed. It is worthy of remark, that this kind of oxygenizement should form so regular a crystallization, for it appears to be only a decomposition of the native copper from which it commences. The lower figures are in different matrices,—one in a red powdery oxide of copper and iron; the other in an ochra- ceous matrix, chiefly oxide of iron. It agrees with the following parts of Mr. Kirwan’s de- scription: ‘* It is often cochineal red, or intermediate be- tween blueish-gray and carmine red. Found massive, in- vesting, disseminating:” he does not mention its being found crystallized. ‘* Fracture even, approaching to the minute conchoidal, sometimes earthy. Hardness 4 to 5, brittle. Effervesces with nitrous acid, to which it gives a green tinge, and a blue to caustic volalkali.”’ Thus much till Mr. Chenevix had shown that there was only one proper oxide of copper of a black colour, and that the present species is rather a suboxide of copper, con- taining Copper? oii: Hake SAE 8825 OXVSEN sae ik Lee aS whereas the black oxide contains 20 per cent. of oxygen. S54 TADB.. ELV. FERRUM suboxygenizatum. Magnetic Iron Ore. Class 3. Metals. Order 1. Homogeneous. Gen. 6. Iron, Spec. 2. Magnetic. Div. 1. Crystallized. ‘Spec. Cuar. Iron in combination with but a small portion of oxygen *. Syn. Iron in a calcined state mineralized by pure air. Kirw., 2. 157. Magnetischer Eisenstein. Emmerl. 2. 278. Fer oxydulé. Haiiy 4. p. 10. Ferrum tesselare. Jinn. ed. 12. t. 3. p. 136. I was much pleased when I discovered this curious crystal- lization in a pyritaceous copper ore sent me, among other favours, from the neighbourhood of Tavistock, by my kind friend Mr. John Taylor junior. The crystals are dispersed through the ore in tolerable abundance; but being small, do not readily distinguish themselves to the unassisted eye: with a lens, however, they are very satisfactorily seen, with the variety of modi- fications here figured, and sometimes, by breaking them, we find them curiously casing each other 2 or 3 times. They are most readily attracted by the magnet, and. will support a part of the gangue of pyrites that may chance to be attached to them, of 8 or 10 times their own bulk. The gangue is said to be rich in copper, and is commonly of a bright and pale golden colour, sometimes with a greenish hue, and often iridescent. * 15 to 24per cent. Kirw. vol. 2. 158. 118 1 do not know that this crystallized variety of magnetic iron ore has been observed in Great Britain before. Dr. Badham gave me a fine octaédron of the Swedish sort, from Fahlun (where such specimens are not rare), which is above half an inch in diameter: but this is not more strongly attracted by the magnet. It is coated with mica, and, within, is of a more or less deep-brown red, as are ours, sometimes ap- proaching steel-gray and black, partly shining, and metallic. Fracture uneven, somewhat earthy. The crystals are ar- © ranged in convenient order, to see the additions that assist in modifying the different crystallizations, (viz.) The upper figure on the right hand exhibits the regular octaédron, the faces of which, by the addition of the la- mine of superposition, or superior coating, form leng six- sided facets, which are those of the dodecaédron with eight triangular faces parallel to those of the octaédron, see the middle figure. ‘These are the nearest approach we have seen to the octaédron in our specimens; with more lamine, it keeps the same form which is shown, but with smaller tri- angular facets in the left hand figure and the right-hand lower gure. In the lower figure on the left hand the laminz have advanced so far as to form the complete rhomboidal dode- caédron. The geometrical outline shows this manner of casing over each other; but we must beg our readers to substitute the octaédron in lieu of the dodecaédron in the centre, as we find is the case upon further examination since the engraving was finished. Sard 1 S830G Pubiijhed by Ja” Sowerby. Londsn.. di ALB, iV. SILEX quartzum, var. arenaceum. Sandstone. Class 2. Earths. Order 1. Homogeneous. Gen. 4. Silex. Spec. 1. Quartz: Div.3. Amorphous. Var. 2, Graniform. Syn. Ferruginous Sandstones. Kirw. v. 1. p. 365. Cos colorata. Linn. Syst. Nat. ed. 13. v. 3. p. 64 SANDSTONES are not uncommonly impressed with the casts of shells, &c. They are little else than granule of flint, with iron more or less oxidated: the oxidation is most con- spicuous in the crevices where the shell has been mixed with a little lime, or other things, giving them different tints. The shapes of many sorts of shells are found in these stones, mostly Arcas and Anomias. The acuminated sides of the Arca on the stone at the right hand seem oer formed, from the peculiar manner of its immersion in the mass. They are often found detached as figured, serve to undeceive us. These Arce, as they surely are by the Jength of the hinge, apparently contain many denticula- 120 tions, or teeth *, the distinguishing character of the genus. The singular rising in the middle of the upper shell, of about 5 pleats wide; and the corresponding cavity in the under one, is a curious character, common, with some variations, to both these and the Anomia, with which they have gene- rally been confounded. The little Anomiz at the bottom are darker, and probably contain more iron. Their struc- ture is certainly remarkable, especially as we, in the present age, have no recent shells in this part of the world at all corresponding with them. We think these the more in- teresting on that account, as they help to indicate, that at certain periods there were some animals very different from those now existing. These were sent me from the Tees by the Rev. Mr. Har- riman, and also by Mr. Winch, im large fasciculi. They are found in other parts, but I do not know how near the present surface of the earth. They are but little crumbly in their fracture, rather con- densed, and approaching to the conchoidal, like flint: they are often very tough, but too heavy for building, and not of any known utility at present: they, perhaps, might be liable. to decay, as the ochraceous substance 1s somewhat scattered through them. They sometimes contain more or less clay. * See Arca, t. xv. p. 395. ee ee ee Ee es mS wie TA B. LVL: FERRUM oxygenizatum, var. radiatum. Radiated Oxide of Iron, or Hematites. Class 3. Metals. Order 1. Homogeneous. Gen. 7. Iron. Spec. 3. Oxide of Iron, Div. 2. Imitative. Syn. Red Hematite. Kirw.v. 2. 168. Rother Glass-kopt.. immer. v. 2. 313. Hematite. Hay, v. 4.105. De Born, v. 2. 287, IC Mesbe Tue Hematite Iron ores are found near Silverstein in Lan- cashire in great variety and abundance. The upper speci- men is somewhat singular, from the separating and divari- cating radi. The lower figure shows more of the usual struc- ture of these ores, which often form large roundish or irre- gular nodules, sometimes kidney-shaped, botroidal, &c. the masses radiating from one or more centres, 6 inches or more in length, and casing or coating one over another. They are mostly of a brick red colour, easily staining the fingers, particularly the powdery parts:—the harder parts also stain the fingers much, and by a little rubbing give a black tinge K 122 with a bright lustre not unlike black lead. Those parte which have lost the red appearance, and approach the me- tallic or iron lustre, do not so readily stain the fingers. On being ground these give a deep red colour; whence this ore has been called Blood Stone. Sometimes the harder black sort with this property is cut into burnishers for gilders. These ores are said to contain from 40 to 80 per cent. of iron. The harder kind is sometimes a little magnetic, if reduced to powder, particularly if heated on charcoal; which deprives it of a certain quantity of oxygen. ‘ Fracture coarse cr fine fibrous, parallel or diverging, earthy.” Hard- ness, from such as may be easily scraped with a knife to such as will strike fire with-steel. Spec. Grav. from 4 to 5, Kirwan. <‘ This ore contains, besides some manganese, a large proportion of argill, which renders the iron it affords red- short, that is, brittle when red hot.” Kirwan. TAB. LVII. SILEX Analcimus, var. compactus. Compact Analcime. Class 2. Earths. Order 1. Homogeneous. Gen. 4. Silex. Spec. 8. Analcime. Div. 3. Amorphous. Syn. Analcime. Haiy, v. 3. 180. Tuts curious substance is not uncommon in Great Britain, wherever basalt ‘and trap are found. We have some spe- cimens from different parts of Scotland, which contain it in nodules. The present specimen came from the Isle of Isla. It is somewhat stalactitical, and extremely various in its shapes, sometimes forming roundish drops from the size of a pin’s head to that of a large pea, and often of a knotty elongated figure like a potatoe. It scems to be a transition from quartz, and decomposes into filaments forming zeo- lite. This specimen exhibits it beginning to form filaments. The bottom of the larger mass, which somewhat resembles the humerus, or thigh bone, of an animal, appears once to have been in a thick fluid state, and might give some idea of the forming of the flints in chalky rocks, (see page 15.) K 2 124 which however is not quite satisfactory to me. More of this will be mentioned in another place. They may be found somewhat various in their colours: The most common are nearly as here represented; transparent white or glassy, and often pearly or greyish within; the outside being coated with a light brown crust often nearly opaque, which gives an idea of fresh cast wax. The fracture is irregular, glassy or flinty. Analcime may be found in most of these appearances so hard as to resist a knife, like quartz; but in the state of compact zeolite, or passing into fibres, it may be scratched with a knife or any steel instru- ment, though it resists iron and brass. We are not sure that this is the true hyalite of Kirwan; who says it does not fuse per se at 150°. Ours fuses per se at the heat which turns carnelian white, which Kirwan observes was 160°. Ae ‘ at * Se TAB. LVIUII. SILEX oe 149 sure, dilate the prismatic hues, so that one or two sets may take place of the 5 sets represented. | We received this specimen from Durham, by favour of Messrs. Harriman and Oliver, some few years since—but did not know how valuable it was until lately—having now discovered that it contains many small drops of water or some other liquid in little hollows, which as far as we know have never been discovered in any other substance except - quartz, or rock crystal. The lower one is another fragment with a curious pearly appearance, and has somewhat the appearance of sulphate of lime or gyps, but may be readily discovered by the weight. TAB. LXXII. TABULAR sulphate of barytes is the most common variety. The finest specimens generally come from the neighbourhood of Cumberland. | The tabular crystals are sometimes transparent, and often more or less stained with ochre; they mostly stand 150 upon their edges, often very distinct and in every direc- tion. It may be observed that their edges are parallel to the diagonal of the nucleus, therefore it becomes rect- angular. The present specimen has small corner. facets, parallel to the faces of the primitive or nucleus. One end has bevelled faces on either side, the angles measuring about 128°, which are parallel to the small triangular facets on the lower figure of Tab. 70. The other has three beyel- lings. See the geometrical figure. WN Tas Sowerdy, Londen. 22804. Published By TAB. LX XIII. CALX Fluor, car. Fluate of Lime, or Fluor. Class 2. Earths. Order 1. Homogeneous. Gen. 3.Lime. Spec. 3. Fluate. EE "Tess specimens are among the rarest of the fluors known in Great Britain. The upper one is in the possession of my very generous friend Philip Rashleigh, Esq. F.R.S.: &c. of Menabilly in Cornwall, whose work and grand collection of British minerals are well known. It is an instructive speci~ men, having the form of a purple octaédral nucleus within- side, and the green modification in order about it, which adds to its beauty as well as curiosity. One side of this octaédron has many small but perfect cubico-octaédrons (or cubes with the corners truncated) of pyrites. The next specimen in value I have the pleasure to possess myself. It is somewhat rougher and rather duller, standing on a confused octaédron, the corners of which are rather prominent, forming, as it were, irregular steps; it includes a small octaédron greener than the rest, but rather obscure, within which is a smaller pur- ple one, but which is not to be seen without turning the 152 specimen about many ways. They both come from St. Agnes in Cornwall. The lower geometrical figure explains this modification complete, in a position to make it familiar, and to show the placing of the octaédron, which is in the position of the common fractures of all fluates of lime. See Tab. 27. and the latter part of the corresponding description. The upper middle four-sided face in all the figures will be found to agree with the face of the cube common to fluate of lime; the four sides of which are bevelled off, and the corners, as be- fore mentioned, are parallel to the faces of the octaédron, they forming six square faces of the cube, eight faces of the octaédron, and 24 beyellings; in all 38 faces. Va TAB. LXXIV. ZI NCUM_) sulphuratum. Sulphuret of Zinc, Blend. Class 3. Metals. Order 1. Homogeneous. Gen. Zinc. Spec. Oxygenized. Spec. CHar. Zinc in combination with sulphur. Syn. Zinc mineralized by sulphur with iron. Azrw. Ue Ne QO Blende, Emmerl. v. 2. 443. Syst. Min. Jameson, Vel 16. Zine sulphuré. Haiiy,v. 4. 167. Brenpe (commonly called Black Jack by the miners) is often found crystallized, but generally in a very confused manner, and most frequently of a deep jet-black. The tetraédral variety, here figured, has something of a less deep black lustre, and approaches to a lead-like appearance. Except one or two solitary crystals, they are generally in plated clusters or groups; the plates, for the most part diminishing from the edges to the centre of the triangular faces, forming three faces, as on the dark side of the right hand figure. Occasionally, each face of the tetraédron will differ ; and one may either be seen plain, as at the base of the M 154 lowermost geometrical figure, or have the above-mentioned three faces terminating in a point like the dotted faces on the distant side, or with another triangular face like the right or left hand sides of the same figure. The truncation of the four solid angles, in the left hand and the geometrical figure, are parallel to the octaédron. These modifications are all evident in the present specimen, which is a Cornish one. They rest on a greenish chlorite, on a light sort of schist or slaty rock, commonly called killas by the Cornish miners. They are often accompanied with rock crystals and copper pyrites. The nucleus is a rhomboidal dodecaédron, and the integrant molecule is a tetraédron with isosceles trian- gular faces, according to Hatiy. The modification called encadré by that authur, among his sulphurets of copper, resembles this very much; but he does not seem to have known such in sulphuret of zinc. Its specific gravity is 4°1665 according to Brisson. It may be scratched with a knife, and it will scratch sulphate of barytes, but not fluor. Refraction simple, Haity. ASS CEO Is the same substance as the last. The crystallization is a very curious one. The edges being truncated adding 6 faces, which, with the truncations and the solid angles spoken of in the last, make 14 faces. The latter faces may be trian- gular, like the three bottom ones, or hexangular like that at the top. These are on a gangue of somewhat dirty green chlorite and quartz, with pyrites. The nature of the accumulation will be seen when we take occasion to figure the primitive form. The well known semimetal zinc, often used as a principal agent in galvanism, for making of brass, &c. is extracted from this ore. * May 2.7304. P: Of hee By Jat Sowerby, Londo. TAB. LXXVI. BARYTES carbonata, Carbonate of Barytes. Class 2, Earths. Order 1, Homogeneous. Gen, 6. Barytes. Spec. 1. Carbonate of Barytes. Div. 1. Crystallized. Gen. Cuar. Pulverulent, white, somewhat pungent. Spec. Grav. 400. Soluble in most of the acids, and in 900 times its weight of water. Its nitrate .does net tinge flame red. Its sulphate is nearly soluble. It forms a hepar with sulphur, which is poisonous. Bab. Spec. CHar. Combined with carbonic acid. Syn. Barolite or a€rated barytes. Kirw.v. 1. 134. Witherite. Syst. Min. Jameson, p. 573. Witherit. Emmerl. v. 1. 546. Werner. Baryte carbonatée. Haity, (DO BORN. We received the fine specimen here figured, from the lead- mine of F. Hall, Esq. at Arkendale, near Richmond, York- shire, by favour of our friend the Rev. J. Harriman, in December 1803. We have since received specimens, from the same place, from Mr. W. Watson of Bakewell, which he gathered in September 1803. It was first found at Angle- N 158 sark in Lancashire only, but has since been observed at several other places. Carbonate of barytes, it appears, was first discovered by Dr. Withering (see Phil. Trans. for 1784, 301.), when it was called aerated barytes; but Mr. Werner, wishing to honour Dr. Withering for his abilities and accuracy, named it Witherite. It has since very properly been called carbonate of barytes. Radiating carbonate of barytes, in its weight and appearance, very much resembles carbonate of strontia; however, it differs from it in never being of a greenish colour, and in having its radu larger, more com- pact, and flatter. , The upper figure represents carbonate of barytes in dode- caédral crystals, formed of two hexaédral pyramids joined base to base, like quartz. These are the largest I have seen, and are very rare at pre- sent. They are covered with a light ochraceous substance, perhaps calamine. The matrix is carbonate of barytes, in part decomposed, and of a chalky appearance. The figures below show the geometrical plan, and in what manner one of the solid angles of the base has been mistaken for part of an oc- taédron, or has given the idea of two four-sided pyramids joined base to base, which many have described as one of its forms of crystallization. TAB. LXXVH, CUPRUM sulphuratum. Sulphuret of Copper. Class 3. Metals. Order 1. Homogeneous. Gen. 10. Copper. Spec. 4. Sulphuret of Copper, Div. 1. Crystallized. Syn. Yellow copper ore. Kirw. v. 2. 140. Copper pyrites. Syst. Min. Jameson. Kupfer-kies. Emmerl. v. 2. 232. Werner. Cuivre pyriteux. Hauy, v. 3. 529. Tus copper ore is not uncommon; but the form of the erystallization in this specimen is either rare, or has been hitherto overlooked by most mineralogical writers. Tetra- édrons have been spoken of, but not with lenticular convex faces, which seems a character of this ore when crystallized in tetraédrons; at least most British specimens have some inclination to convexity. These appear to be always in~ clined to tarnish, very often assuming a coat, either of the colour of blued steel, or blueish black ; and it often has the green patina, or oxide of copper, on the surface, which count Bournon speaks of in his description of yellow cop- per; Phil. Trans. for 1801. When fresh broken it is of a N 2 160 bright greenish yellow colour with a metallic lustre, and the flaws tarnish to the various colours of what is commonly called Peacock Copper Ore. The fracture is smoothish, having more or less of a fine-grained surface, sometimes like the finest sand, as count Bournon has observed. The crystals are brittle, and too tender to strike fire with steel. The left hand sides of the two figures show the inclination to form three trapezoidal faces on the triangular ones; and the figure between two columns of quartz shows them more plainly, as it does also the signs of the triangular lamine of superposition. © This 1s taken from another Cornish speci- men. The geométrical figiire shows the somewhat obtuse te- traédron, each face of which is replaced by three trapezoidal ones, making a dodecaédron. ‘The nearest modification to this kind is in Romé de Vsle, ¢ab. 1. fig. 28. but this has twelve additional isosceles triangular faces. Haiiy has a crys- tal something like this in sulphuret of zinc, which he derives from the rhomboidal dodecaédron. See his fig. 197. The rounded tetraédral crystals are therefore passing to the dodecaédron, in an almost imperceptible manner, as the three figures on the second line show. This specimen has some more perfectly marked, and some truncated like the two left-hand figures. Tare 7.22 161 TAB. LXXVIILI. WE continue this modification with a very curious ya- tiety of the same substance, probably less rich in copper, although differing very little in the lustre or colour of the fresh fracture. The outward aspect resembles the grey or vitreous copper ores, being of a dull grey colour, and very roughly formed, as it were of certain nuclei, which viewed in the direction of the solid points, or angles, give a peculiar bright shining glare. Its faces are more determined and flatter than in the last: the three trapezoidal ones of the same are not finished (see the right-hand middle figure), but leave a tri- angular face, transverse to the original face of the tetraé- dron, forming one equilateral and three isosceles triangular faces on each side, which makes altogether a new sixteen- sided figure. This is a modification very different from any before mentioned. Haiiy only finds the modification from the bevelling of the edges of the tetraédron, as in his grey copper and copper pyrites, tab. 70 and 71, fig. 78 to 89. However, the faces o on figs. 81, 85, 86, 87, 88, 89 ap- proach it; but the angle of incidence is that of the rhom- boidal dodecaédron, or 120°; whereas ours is that of the dodecaédron with isosceles triangular faces. Most of the crystals in this group are truncated at the edges, like fig. 27 162 of Romé de I’Isle (see our geometrical figure at the bot- tom). These sloping truncations add 12 narrow pentagonal faces; and thus we have a new figure with 28 faces. Copper pyrites may be known from iron pyrites by its brassy colour, smooth fracture, and not striking fire with steel. Sawarde + FRY Fere-1.1604-. Pubbfhed By Fa TAB. LXXIX. CALX carbonata; var. petrosa. Variegated Limestone; or Tirte Marble. Class 2. Earths. Order 1. Homogeneous. Gen. 3. Lime. Spec. 4. Carbonate of Lime. Var. 3. Amorphous. Syn. Common compact limestone. Syst. Min. Jame- son, 477. pied ly cone sirivetsy vllwteme Tuts beautiful variegated limestone comes from the hill of Belephetrich in Tirie, one of the western islands of Scot- land. It is said to be a primitive limestone, but is not mentioned in Mr. Kirwan’s Geological Essays. It has all the common characters of a limestone, with a fine splintery fracture*. It is admired for the white and red, blending and softening into spots, blotches, and undulating striz, more or less interrupted by bright little red stones sticking within it like little garnets¢, which are somewhat trans- parent, smooth, irregular, and seem to be quartz (see the lower red-coloured figures): also white transparent calca- reous spar with the common rhomboidal lamellar fracture is occasionally mixed with the stone; but more especially a light or dark olive green substance, either of an earthy or ' * Primitive limestone is not always white, nor is the grain of it always very perceptibly scaly or lamellar; but approaches, by reason of its minuteness, so nearly to the compact as to pass for such: nay, it is said sometimes to discover a splintery fracture, but very rarely; sometimes its texture approaches to the fibrous. Kirwan’s Geol. Ess. 215. + Jameson says it contains little garnets : we do not find any in the quantity pf some tons which'we have had the opportunity of examining. 164. shining appearance. The earthy sort at first sight resembles chlorite, but is more or less rhomboidal in its fracture. It seems to be mixed with quartz, and is irregular as to hardness. This green substance is mostly very irregular as to shape. We could only discover a small inclination to hexangular columns with irregular ends: these are some- times smooth and shining, and have whitish transverse striz, which give them the appearance of an onyx: these striz are softer than the other parts (see the middle figures) : some of these have a resemblance to jade, as Raspe ob- served, but perhaps only from their outward smooth aspect. The lighter ones, we presume, differ only in colour, and are probably the same substance; indeed, Jameson calls them all hornblendes. We have had the pleasure, through the kindness of Mr. Hatchett, of seeing the corundum from Tirie, spoken of by Mr. Jameson, and find it the same sub- stance with these crystals, only much lighter in colour: but, as Mr. Greville observes, they are not fusible, as Kirwan and Jameson say hornblende is, therefore they can- not be hornblende ; nor are they now supposed to be corun- dum, although the external appearance of the lighter varieties much resembles that substance. We, at present, only men- tion these crystals because they occur in the Tirie marble, but must show larger specimens, and explain them further hereafter. | Mr. Jameson in his Mineralogy of Scotland, v. 2. 30. de- scribes the red-coloured marble of Belephetrich as follows: Colour, pale blood red, light flesh red, and reddish white. Lustre, none, except from a number of dispersed shining folie. Fracture, fine splintery. Transparency : transmits light freely at the edges. Hardness: yields pretty easily to the knife. DAG, boc “STANNUM oxygenizatum. Oxygenized Tin. Class 3. Metals. Order 1. Homogeneous. Gen. 6. Tin. Spec. 2. Oxygenized Tin. Div. 1. Crystallized. Spec. CHar. Combined with oxygen. Ocrazprat crystals of oxygenized tin, destitute of any truncations, bevellings, or other modifications, I understand have never been yet found ; those here represented are among the nearest known to that simple figure. My friend Mr. Richard Phillips, who possesses one of the finest and earliest collections of tins, &c. from Cornwall, lent me one of his best specimens for this figure, and Iam possessed of a similar specimen. They seem in every thing so very like each other, as readily to imply that they came from the same place. They are very black, with much lustre, lying in every direction; some are, macled or transposed with various truncations, bevellings, &c. The middle figure at the bottom shows the most perfect octaédron I have yet seen. The edges of the pyramids are truncated more 19) 166 or Jess; the prism is perhaps shorter than here represented. The left-hand outline shows what it should be as a perfect octaédron. The angles of the base of the two pyramids are 90°. Those of the face at the summit are 70° 31’ 44”, and at the base 54° 44’ 8”. There have been two opinions concerning the primitive form of oxide of tin: the one, thatit is an octaédron ; and the other, that it isacube. We have obtained very neat frac- tures parallel to four faces of the latter, and signs of faces inclined upon them, so as to form a rhomboidal dodecaé- dron. TA Bay LX XXL Goop specimens of oxide of tin with the proper four- sided column and corresponding pyramid, if the edges are not bevelled, or truncated, are somewhat rare. Some crystals on the present specimen are of this form, and others are truncated on the edge of the column, making a fifth face; which truncation is generally continued up the edge of the pyramid. A four-sided column without truncations, or a pyramid, would be a great curiosity, oF Zonder 3&2 “ 167 TAB. LXXXII. THE figures here represented approach the dodecaédron as nearly as any that I have yet met with of British origin. Tt will be readily seen that the edges of the four-sided pyramid, as truncated on the left-hand figure, if continued so as to obliterate the octaédral faces, would form, with the help of the four-sided column, eight of the faces of the dodecaédron, the other four faces being hid in the gangue; and, if with a short column, the faces would be all rhom- boidal ; but if the column be long, the columnar faces will be hexagonal. As yet we have not seen a dodecaédron with both pyramids complete. These specimens are not so black as most, and are modified very roughly. They have also somewhat of a rusty ochraceous hue, probably holding more oxidated iron than usual. We are obliged for this specimen to our friend Mr. Richard Phillips. We have some like it, but much smaller. Rtas Har aN! 0 be Eamon 28 uri: i i Oy addy sary Pie is 9 at to 2 : IO eS ine yusot 19 i 7] 3 i ; mead Usad Dhaai at A ait etnulos ale oe 8 | ye ad ( a Cid} te hits iw e908} ieK tiple act AEE ad -crnaloo odd | { srordiaigash ob 8) mace dom ovad 2) i 100 ain’ 0 acento: ne cot 4 fi AY Ase a SUR andl) not beiebixe oxo 1 gobo “it baatik aso ot anno. aint Oe Moog IH th, avi dou tod re 33 Te 2 .r804d LeBifheds or Te Sowerby, Loraine TAB. LXXXIIL. SILEX Quartzum. Agate Pebbles. . Class 2. Earths. Order 1. Homogeneous. Gen. 4. Silex. Spec. 1. Quartz, Div. 3. Amorphous. Syn. Quartz agathe spheroidal. Hazy, v. 2. 423. A carte appears to bea very antient name given to this kind of quartzose stone. It is found on many parts of our shore, as at the Bill of Portland, Lowestoft, and on the Welsh, Scotch, and Irish coasts. It is sometimes found inland, about the lochs in Scotland and Ireland; and, occasionally, in the gravel-pits about London, &c. This species has been much admired for its resemblance to many oriental stones; and differs from our common pebbles by its toughness, which preserves it from large in- ternal flaws. According to its transparency or colour it is more or less valuable, depending on the taste of the owner. Such productions often become pledges of regard, or memo- randums of past hours employed in gathering them; and are thus more esteemed than for their intrinsic value. P io Exclusive of these social ideas, they are often equal to the best foreign agates, and bear cutting and polishing equally well. We shall speak of the striped and otherwise marked stones hereafter. The agates found on the sea-coast, being rolled and jum- bled together by the force of the waves, are roughened ; but being hard, this roughness penetrates but a little way, and the utmost force they experience seems only to make little circular flaws; or, if I may be allowed the expression, more frequently little crescents or semi-circular flaws, from the impulse of the blow coming in a lateral direction. The right hand specimen is from the Bill of Portland. Its outer surface is generally as here represented, but sometimes whiter. The left hand top specimen came from Lowestoft, and was, perhaps, formed by aggregation, as most agates seem to be (possibly ina trap rock, see Tab. 58),-as the cloudy appearance within seems to indicate. The next figure is of arougher formation. It was sent by the Rev. H. Davies of North Wales. The smooth one on the right hand, with a little red about it, has been called a carnelian. It was found at Lough Neagh in Ireland: but it must be observed “hat agates, especially British ones, should not be confounded with oriental carnelians, the fracture of the agate not being so shining, and the stone much harder*. The next specimen on the left is a rather pellucid fragment * This is well known to lapidaries, seal SNEED &e. as it costs ther more labour and diamond dust to work them. 171 with the edges partly blunted. The inner figure on the same ime was given me by Mrs. Abbot of Bedford, who picked it up in Derbyshire. The smallest of the two lowest ones is ap- parently a fragment, remarkable for the resemblance to part of aseptarium; the inner part resembling the upper right hand figure with a coat of a different colour. » The largest JSigure at the bottom has a resin-like appearance, which these stones occasionally have, and was given me by D. Turner, Esq. who brought it from Ireland. Agates that are found in Scotland resemble all these; but what are found there, especially near Perth, are admired for being striped, zoned, forming onyxes, or speckled with various blots, &c. resem- bling eyes. Mocoas are a sort of agate with dendrites or figures like sprigs, trees, &c. which seem to be iron, some say manganese, formed in a peculiar manner with the stones, especially the oriental ones, which are durable; but those called German Mocoas by the lapidaries, seem to have had the branching figures introduced by nature or art into their flaws, and such are apt to disappear, often to the great disappointment of the wearer. We digress a little in speak- ing of these, which are foreign subjects, as we do not yet know of any stones worthy to be termed Mocoas found in Great Britain. We consider agate to be nearly of the same nature or a variety of chalcedony. It is said to contain Silex 84, Argil 16. P2 aes 1% } am ike meee Pe ere P Lets. NAME SU SSP ei co Pie ‘ Ry Sanrio ff re a Teresita k ae 7 fi vernte ia aes) or Ger ec ThE ae) 7 ¥ if Z Saar ; a » DY ALLS pa ee sei Ft . SP ae = y parks P wf gay } ere f POPE DS. Sacet ig ab a as cs pe PUA 2 A ¥ ce RA id UEC x + mit i ; phe Le fe a Hi, . 4 j i hy \ = ; St , Pa ee: Geet why Less y % 1 ak i Jae. ; t “ihe - ¥ iy id ) Riser ee cee e y Ske BEST UES yh - A ‘s Kes 1 82030 if : Th 4 % A Astin : i evi a i einen) emit vit P BS} EES : . SUTTONS Sely 1.2604. Prut/hed By Jat Sowerty, London: I TAB, LXXXIV. PLUMBUM phosphatum. Phosphate of Lead. Class 3. Metals. Order 1. Homogeneous. Gen, 14, Lead. Spec. 3. Phosphate of Lead. Div. 1. Crystallized. Spec. CuHar. Combined with Phosphoric acid. Syn. Phosphorated Lead ore. Kirw. v. 2. 207. Grun-bleyerz. Emmerl. v. 2. 394. Braun-bleierz. Ibid. 283. Green Lead ore. Syst. Min. Jameson. Plomb phosphatée. Haiiy, v. 3. 491. Tue yellow phosphates of lead of Wanloch-head mines, Scotland, are found coating Galsena in the Bellan-grain vein, from 20 to 30 fathoms below the surface, but gra- dually disappear at greater depths. From this mine our specimens came by favour of G. Laing, Esq. They are found in other parts of Great Britain besides Scotland, as Wales, Cornwall, Ireland, &c. The purest phosphates seem to be of the brightest yellow, and the crystals are generally very small, being mostly hexaédral columns and their modifica- 174 tions. The present is in very perfect hexaédral columns, and its yellow varies in intensity, with a greenish and brownish cast. The crystals are soft, brittle, easily scraped with a knife, and the powder* corresponds with the colour of the crystal. The crystals will easily scratch carbonate of lead. Fracture splintery and conchoidal. ‘ Integrant molecule an irregular tetraédron. Primitive form a bipyra- midal dodecaédron.”’—Haiiy. We find these at first, by exposure to the blowpipe, turn green; then they assume a pearly cream colour, and afterwards become irregularly fibrous. The heat being continued, these fibres unite in a somewhat concentrating manner, forming various polygonal facets in an irregular sort of crystallization: see the left hand figure at the bottom. This substance is sometimes situated on an amorphous matrix of its own nature, or on quartz, ochraceous quartz, galzna, &c., as before observed. * It is said to be gray by Haity, let the colour of the mass be what it will. &S TAB. LUXXXY. STANNUM oxygenizatum. Oxide of Tin, in Crystals with 8-sided RP yramids. Etain oxydé opposite. Alaily, v. 4. 141. "Tuis is arare modification. It is an incomplete 8-sided pyramid placed upon a 4-sided prism, at an angle of 155° according to Romé de I’Isle, and of 158° 45’ 27” according to Hatiy. This pyramid is always terminated by another 4-sided one parallel to the octaédron. They either stand on the gangue upright, with one end only finished pyramidally, as appears from the middle figure on the right hand, which is a large and curious detached crystal: being broken at the top, it gives an indication of a point, but on examination we find it cased on an octaédron, which probably it once covered regularly; or they lie on their sides and are pointed at both ends: see the left hand figure. They are seldom large. The gangue is as usual to tin crystals, viz. rock crystal, chlorite, and chlorite schist, or killas of the Cornish 176 -miners. The geometrical outline on the left hand shows the commencement of the 8-sided pyramid on the edge of the prism. There are many varieties of this modification on this specimen, and sometimes of twothem meet base to base, and form a mackle: see the bottom figure. TAB. LXXXVI. MANGANESIUM oxygenizatum, var. Primitivum. Oxide of Manganese. Class 3. Metals. Order 1.. Homogeneous. Gen. 2. Manganese. Spec. 2. Oxide. Div. 1. Crystallized. Var. 1. Crystal primitive. Gen. CHar. Spec. Grav. 6.85, somewhat mallea- ble. Colour grayish white, very difficult of fusion, even more so than iron. Colours glass violet. Does not combine with sulphur. | Spec. CuHar. Combined with oxygen. Syn. Manganese mineralized by oxygen, Kirw. v. 2. 291. Gray manganese ore, Syst. Min. Jameson. Braunstein. Emmerl. v. 2. 522. Manganese oxydé. Hay, v. 4. 243. Mawneanese (which was first discovered to be a new me- tal by Bergman), and which has since been found in a na- tive state by Mr. La Perouse, in the valley of Vicdessos, near Sem, in the neighbourhood of Foix, Pyrénees, who 3 178 says it is imbedded in oxide of manganese; is of a silver gray colour with a metallic lustre; divergingly foliated texture, somewhat malleable, and that it soils the fingers. Not knowing of its being found hitherto in Great Britain, we give this short account of it, and shall be glad to be favoured with any specimens which may be met with here- after. We describe with much pleasure the present speci- men of crystallized oxide, as propitious to an expectation that Great Britan nearly includes all that is essential to a knowledge of mineralogy, very few genera being excepted. Mines have been worked in many parts of Great Britain for oxide of manganese. I have some specimens -from Mendip Hills in Somersetshire, crystallized in small short rhomboidal prisms. The one figured is crystallized in elongated ones, which have striz on their sides that agree with the fracture. We also find the apex show signs of a diédral or tetraédral summit. The upper right hand figure is nearly the natural appear- ance and size of the specimen; the prisms standing irregu- Jarly and joining near the base, where they stand upon sul- phate of barytes, &c. The gangue is a sort of stratified micaceous grit, through a stratum of.which it runs in veins. In a mass sent me from Aberdeen, the manganese includes crystallized sulphate of barytes, &c. as trap sometimes does other stones. The left-hand upper figure is magni- fied, and-shows how irregularly the crystals stand on the mass in some parts. The left hand lottom figure shows 179 ‘the upright strize on the prism, and the apex exhibits the diagonal ‘strize, and on some crystals a slight beginning of the two faces which sometimes meet on the centre. The left hand figure shows these striz meeting in four directions ‘to the centre, with the cross diagonals, giving signs of 4 or -more faces. The prism is sometimes truncated so as to form eight sides. Hatiy knew of no other than these eight- sided ones, with 2 or 4 summits at the apex. We first read of short tetraédral prisms of oxide of man- ganese in Catal. de Raab. v.2. 130, from Naila, in the mar- gravate of Bareith, in Germany, and soon after of rhom- boidal tetraédral prisms, neatly truncated at their extremi- ties, from Ilmenau in Saxony. These of course are in Mr. Greville’s matchless collection; we find the latter mentioned, as from II field, in Dr. Babington’s catalogue of the collection, now belonging to sir John St. Aubin, p. 255. We are glad to be possessed of British specimens from the works near Aberdeen, which I have been given to understand were first discovered by the Rev. Mr. Smith. My friend, Mr. James Reid, among other similar favours, procured me the specimen figured, some time in the year 1803. It agrees exactly with the two last specimens mentioned in Catal. de Raab., in which the word truncated is certainly superfluous, rhomboidal prisms simply, being assuredly meant. This is considered as the primitive form by Hatiy. Oxide of manganese is used in glass-houses in small quantities, to clear and discolour glass by giving up some of ] * 180 its oxygen, and so completing the vitrification of the iron or other colouring ingredients. It is used asa pigment or an ingredient in printer’s ink, and to procure oxygen gas from, for many purposes, viz. as a medicine; or for oxygenizing muriatic acid for bleaching, &c. About two quarts of this gas may be obtained from an ounce of oxide of manganese. Ag 87 WA BS: UX XX V IT: FERRUM arseniatum. Arseniate of Tron. Class 3. Metals. Ord. 1. Homogeneous. Gen. 6. Iron. Spec. 8. Arseniate. Div. 1. Crystallized. Var. Primitive. Spec. Cuar. Combined with arsenic acid. Syn. Arseniate of Iron. Bournon in Phil. Trans. 1801. ‘Tus was mostly confounded with arseniate of copper until the celebrated Chenevix, by analysis, ascertained it to be an arseniate of iron: see Phil. Trans. for 1801. Count Bournon observes that it crystallizes in cubes rarely a little flattened: I may add rarely lengthened. 1, however, have ita little so, perhaps the fourth of its diameter; and his figure conveys that idea, although I suppose unintention- ally. The sides, he observes, are smooth and brilliant. I am happy to add another character, that they are diagonally striated in alternate order on each face; this is readily seen in most of my specimens*. They are often a little concave in the centre, and rising to the edges in the longitudinal direction of the striz, and also show signs of being formed on cubical nuclei. I have them from a light yellowish * See Ferrum sulphureum, tab. 63, in which the striz are parallel to the edges of the cube; and Count Bournon has discovered a new species of cubic oxide of iron with the striz at right angles, parallel to every edge of the cube: perhaps these striz may become marks of importance 182 K green to a bright perfect green, apparently neither inclining to yellow or blue, passing on to deepish blue green, and thence to an olive colour, being heightened, as it were, with red ; then, the yellow and red prevailing, they are of abrown- ish resin colour: some are very pellucid and transparent, and all so in some degree. The upper figure shows them of their common natural size in a gangue of quartz mixed with oxides of copper and iron, &c. The middle figure is magnified to show their construction more readily; and the right hand geometrical figure shows the strie. In the left hand bottom figure, the only modification known of this substance, according to count Bournon (to use his own words), “* Four of the eight solid angles of the cube are ye- placed by an equal number of equilateral triangular planes, situated in such a manner that every one of the sides of the cube becomes an elongated -hexagon, having two angles of g0° each, and four of 135°. Crystals modified in this way are very scarce. I have never seen but one specimen, which is in the collection of sir John St. Aubin. _ Its crystals are pretty large and well defined.” I therefore consider as a great rarity a specimen in my museum, which exposes two crystals thus truncated. It is easily scratched with a pin, but it scratches common calcareous spar. By Chenevix’s analysis it was found to contain Silica - - - 4 Arsenic acid - 31 Oxide of Iron - 45:5 of Copper 9 Water - - - 10°5 100°O Tas Seveds, Lenador TAB. bh XXXV IL, SILEX Quartzum. Flint Pebbles, §c. Class 2. Earths. Order 1. Homogeneous. Gen. 4. Silex. | Spec. 1. Quartz. Div. 3. Amorphous. Syn... Flint. --Kirw. v..1. 301. Feuer Stein. /mmerl. v. 1. 143. Quartz agathe pyromaque. daily, v. 2. 427. Furr pebbles, so universally known in the vicinity of London, are not so well known every where, even in Great Britain, since one may travel many miles in some counties without finding any. The forms and colours of common flints are extremely va- rious, and they give strong indications of being formed by in- filtration and ageregation among the softer argillaceous rocks ; as the agates, &c. seem to be among the harder rocks of a si- milar natrue; see p. 170: the siliceous infiltration being more or less coloured by oxide of iron, gravitates, or aggregates, into various forms. The upper peblle at the right hand is white at one end, > gradually becoming grayer towards the other.end, witha 184 line or two of interruption, and at length assuming the colour and texture of common gray flint*. The uncoloured part is sometimes less indurated, but insoluble in acid, and seems only destitute of the colouring matter. The coat appears to have been formed when the process was nearly complete ; as drops of coloured water, or turpentine, will, in general, form a margin in the same manner on_ substances on which they are put: the others seem formed in a similar way, varying as to regularity. An approach to yellow, with a border of dull crimson, is seen in the next stone, and the coat is nearly black with very little variety. The next right hand figure was given me by a friend who found it near Norwich. It is remarkable for the unifor- mity of the ochraceous tint all through it, and the dark coat penetrating it in the cracks, which seems to confirm the idea of the margin being formed as the substance was beginning to harden. The next stone is very regularly formed. In this, one of the circles is of as true a yellow, and nearly as bright, as I have ever found in flints. The faces of broken flints sometimes become of a brighter yellow when they have been exposed to theair. The upper central one is more irregular, but isin the middle as bright a cinnabar, or vermilion, as can perhaps be found in these sort of stones, and resembles red jasper. The fragment beneath has been * The common ingredientsare Silex - 80 Argl = = 18 Lime = 2 185 irregularly modified. It is of the brightest crimson in the centre. The lower left hand figure is uniformly of a red jasper colour, which is not very frequent. Its fracture shows it to be not so tough and hard as jasper. This is rather partially covered with an ochraceous hue. The grey and black flints are not very rare: they are mostly found in wet clavey places, and are often very black, sometimes shining, or blotched with grey or a whitish hue; and, when so, are mostly lighter within under the black outside, and darker under the grey outside. Pebbles, if of a fine ochrey hue, from the size of a horse- bean to that of a Windsor-bean, are used for making foot- ways or walks in our best gardens; and are sold in the vicinity of London from 10 to 12 shillings per load, under the name of gravel; the coarser sort are used to mend the roads*. They are often useful, as at Sandown Castle, near Deal, to defend the coast from the encroaching ocean. They are certainly of more use than they are imagined to be in agriculturet; and protect the vegetable earth from the violence of the high winds, while they retain the night- * It might be observed that they shou!d not be brought from the damp pits in which they are found to sudden heat or cold, as it makes them rotten, unless intended to be rendered so for manure. + Soil may be amended by the judicious farmer by adding or diminishing their quantity according to what he wishes to cultivate; their composition, size, sponziness, softness, hardness, and even shape, are of much consequence. Qa 186 fallen dews and moisture necessary for vegetation. They also defend the roots from the too sudden and scorching heat of the sun in the day. They seem admirably suited for this purpose, as their texture is such as to imbibe heat rather slowly. Thus their being common is a happy providence, and it is very reasonable to suppose that every pebble has its destined use. A great deal more might be mentioned respecting their utility im agriculture; but if what has been said is attended to, it will be found sufficient in this place. We may observe that, when free from flaws and of a good colour, they will bear cutting, engraving, and polishing, as well as the orien- tal carnelians, which they partly resemble in their shining fracture, and almost equal hardness. a9 TAB. LXXXIX. PLUMBUM carbonatum. Carbonate of Lead. Class 3. Metals. Order 1. Homogeneous. Gen. 13. Lead. Spec. 2. Carbonate. Div. 1. Crystallized. Spec. Cuar. Combined with carbonic acid. Syn. White lead ore. Kirw. v. 2.203. Jameson. Weisses bleierz. Emmerl. v. 2. 388. Mine deplomb blanche. De Lisle, v. 3. 380. Plomb carbonaté. Haiiy, v. 3. 475. Canrzonate of lead has often a great resemblance to car- bonate and sulphate of barytes. It has, however, the advan- tage of weight, is generally more milky in its appearance, and is mostly shorter in the cro3s fracture; it is also softer. When crystallized, it is more deceptive, assuming the double pyramidal dodecaédron of quartz. It is however most readily to be scratched with a knife, which quartz will not admit of; and when carefully examined, there are very few specimens of this sort that do not indicate a very curious tendency to forming one crystal out of many plated ones. These plates are often so placed that it is difficult to a2 188 see the modification, especially to an unpractised observer. They often imitate the plated crystals of sulphate of barytes. The present specimen is a very fine one, obtained some years since. This shows that they sometimes originate from the decomposition of galena, and they are here yet coloured with it. The matrix is composed of galena mixed with fluor. This very curious specimen has the first modifica- tion of the quartz-like crystal, deduced from the primi- tive rhomb (see the left hand outline), with the column just visible: these pass into regular dodecaédrons, with very short columns, or rather octo-decaédrons; and also form the same figure in plates, which, if regular, show the surfaces of 12 intersecting planes or facets: see the right hand lower figure: but these are seldom quite regular, and they may be so confused and indeterminate that we cannot make them out: see fal. 90. The under figure is a modification seen on the same specimen, formed by the primitive before spoken of, having a larger deposition on some of the faces than on others, which gives it alengthened appearance. Analysis by Westrumb: Oxide of lead 81:2 Carbonic acid - 16°0 Lime - =) "O79 Oxide of iron - 0-3 Loss - - 1:6 100°0 Wi MP) Ate SHAT. 1309. PeBy ze Te Sowerby, Lon Dr. GO GL 7eaTe Zz. Ze Sep 2.2804, Pubbfred By Tei SowerZy, 189 OBS Se: THE specimen here represented would, very naturally, be taken for one of quartz, which it much resembles ; and per- haps it might be passed over by casual observation as such. It came from the lead hills near Glasgow, and is very valua- ble. It is figured of the natural size, and has part of a large hexaédral column very distinct, with many eighteen- sided crystals, either like the outline in the middle at the right hand, or like the lower figure at the right hand, with the column interrupted as it were in its formation, giving them the appearance of the buttresses often used in Gothic architecture, and adding many faces to the sides of the crystal, as well as giving additional angles to the faces of the pyramid. They vary much; one is nearly like the left hand bottom figure with 13 faces, having a pyramid at one end only. PA Be: MCL Tuts specimen, lately sent me, by favour of Mr. Laing, from Wanlock Head mines, near Glasgow, shows the dis- position of the last mentioned substance to form plated octo-decaédrons and other modifications, inclining to the appearance of sulphate of barytes, by forming a sort of trun- cation on the edges. Thus the left hand Jigure is truncated 190 on the edges of the original six-sided column, forming six~ sided faces : see the dotted lines on the column of the right hand figure, and also the apex which is terminated by six trapezoidal faces. Thus we should have 48 faces if they were regular; this is certainly a curious modification. Mr. Laing judiciously observed, that the sulphuret of lead, or galeena, in most cases, where it is decomposing to form carbonate of lead, has a blue tarnish. It sometimes also becomes dusty or crumbly. TAB. .XCIT, SILEX Quartzum, var. aggregatum, Quartzose Pudding Stone. Class 2. Earths. Order 3. Aggregated. Gen. 2. Silex. Spec. 1. Quartzose. Syn. Pudding Stone. Kirw.v. 1.360. Bab. 131, Quartz-agathe breche. Hawy, v. 4. 461. Poudding. RR. De Lisle, v. 2. 481. Tits is not rare, in gravel-pits, In many counties of England; Hertfordshire is however most famous for pro- ducing it. Pudding Stone is little known abroad, and is therefore esteemed in Germany, and other parts of the continent, as an English rarity. I believe it is not found either in Scotland or Ireland *. The most perfect and most esteemed specimens are those which have the closest and finest siliceous cement, with the greatest number of variegated pebbles, sometimes with fanciful representations: see left hand part of the figure. They are much the same in texture and hardness through- out, as the flint pebbles figured in tal. 88, and bear a polish equally well with them. The upper figure is one of this sort, but is better in some parts than in others. The sides show an imperfection, as * Though in Scotland they call some of the rocks by this name. 192 some of the pebbles are broken out, having been rather moulded than cemented, and almost loose when found. This specimen, I believe, is from Hertfordshire, where some people assert that they grow! This kind of stone was greatly sought after about a century ago, to be cut into trinkets, snuff-boxes, coat-buttons, &c. The lower specimen came from South-end, Essex, and was given me by Lady Wilson. The opposite shore, at Sheppy Island, Kent, has many varieties of it, probably washed out of the curious marle clifts of that place. This specimen is somewhat too sandy, and not close-grained enough to bear a polish. They are sometimes found very’ Jarge, and I have seen fragments of them that must have - been several feet in diameter, which had been formerly worked into querns to grind corn, Probably the name was given by English lapidaries ; and, as Mr. Kirwan observes, they meant, by the appellation of Pudding Stones, to express flint pebbles of any colour ce- mented with a substance of the same or a similar hardness, so as to make an equally compact stone for polishing. ee at? «> Cob" 12804. Pobifhed By Fat Sow TAB. XCII. CUPRUM arseniatum. Arsenate of Copper. Class 3. Metals. Order 1. Homogeneous. Gen. 9. Copper. Spec. 8. Arseniate. Syn. Bournon. Phil. Trans. for 1802. ‘Turs beautiful specimen of Arseniate of Copper was lent me by my good friend Philip Rashleigh, Esq. of Menabilly. It comes from near Gwenap. The crystals are spoken of by Count de Bournon as his third variety, ‘¢ perfectly regular for a part of their length, and fibrous at their extre- mity.” The present specimen has these crystals with ap- parently four sides of the octaédron, lengthened into fila- ments, and divaricating a little from a centre, forming al- together a sort of brush, narrow at the base, widening towards the apex, and terminating a little abruptly in a | sharp or angular point. They are of a dark dull green, somewhat transparent, the ends being generally more opaque and lighter, owing to their fibrous nature : some crystals 194, are of a darker green colour and more confused: seq the left hand figure. The ganoue is chiefly quartz, somewhat plated and chrey, and has utermixed with it bright green arseniate? ‘ of copper ia irregular granule: see the right hand figure. Wis VEE G4 TAB: XCly. CUPRUM carbonatum. Carbonate of Copper. Class 3. Metals. Order 1. Homogeneous. Gen. 9. Copper. Spec. 3. Carbonate. Div. 2. Imitative. Tue present specimen is a very rare and curious modifi- cation of carbonate of copper. At present I know of only two specimens ; one belonging to P. Rashleigh, Esq., and the other in the possession of Mr. R. Phillips. The upper figure, which belongs to the former gentleman, is, as he observes, remarkable for being on the broken end of a large milky rock crystal. The other stands on the crystallized ends of the rock crystal, and is a much larger specimen ; part of it only being figured. | This mineral was first considered as an arseniate of copper, but we have every reason to suppose it to be a carbonate. The spicule are curiously disposed like radii round the edges of a thickish lenticular nucleus. Both specimens are accompanied by a few crystals of each yariety of arseniate of copper, figured at tal. 31. bi Fa ae iS ‘ f ooh mae P Ones ae " MS ‘ san } He hak | ‘ FG wae ay s ape = : TAG ts be ; Pan 5 PE Oe ee 1 , : us fi hme pe eantan aep rere cme ! ‘ a < oy | £ pe a ya oS Sars te o. — rs ve ae aa. tx i 3 tial ofad- one 7 ace ees HOLL RSOT Sits ate re yc\4 Bi ‘ot ie. ‘ # } ' x s hi ¥, i omer | “ P > ‘* ve eve } 9T (Taig $2104) BSA OER ALS hive te ttord seit an ase yok abteetan ‘ = ~ = | a ee Brest ot ara ss oti aio eham@a wile’ SPS (ee) AIOT Hive ‘ ie f ‘ ¥ r S tee £. seis omte's ef bas loins door 57 16 eho how . =2 ‘ad x oh } "3 a ’ © <9 % ~< } a hie oh > gied wlie 3846 eq PB pis a. e¢| borabieaos Jenit. dav ilersaion PD) auld batior Fines ii ait. shady aisonttds ¥ ots aan iis tapi cl hems ay w: ey i 2 40 lads: ad aah» a qd boi SS gh a oe fpure uigit Oct 2.1244, Lublifhed by Jae Sowerty, Lordon - TAB. XCV. BARYTES sulfata. Sulphate of Barytes. Class 2. Earths. Order 1. Homogeneous. Gen. 6. Barytes. Spec. 2. Sulphate. Div. 1. Crystallized. Tus curious specimen was sent me from Cumberhead lead mine, at the head of the Nethan river, in Ayr-shire, by G. Laing, Esq. It is remarkable for the crystallized sul- phate of barytes being immersed in amorphous sulphate of barytes. Not having before seen a fracture that indicates the integrant molecule, we are glad to make use of this specimen to show the form of one. It is certainly very rarely to be fractured parallel to all its faces, some of which are not at all to be seen, and it should seem that Hatiy had only observed them by the scintilla- tions within the crystal. To explain the nature of the crystals formed in the upper figure, we have drawn a distinct outline in the middle one, including the nucleus, to show its situation. It will be easily seen that the perpen- 3 198 dicular face at the left hand * end is parallel to the diagonal division of the nucleus, aud the oblique fracture is parallel to one of the faces of the rhomboidal prism ; the perpendi- cular lines indicate a continuance of the diagonal fracture, the others a continuation of the rhomboidal fracture. These are extended in the specimen more or less perceptibly until lost in small nuclei, at the right hand end of the crystalli- zation. The thitd figure may help to familiarise these things by its being placed in another position, and showing similar facts. The lower figure shows the geometrical divisions of the nucleus into two molecules, by means of this fracture parallel to the shortest diagonal of the rhomb. Having seen this, we cannot doubt the opinion of Haiiy; that there may be a fracture parallel to the longer diagonal, dividing the molecules above mentioned into two: thus four upright triangular prisms form the rhomboidal prism or nucleus, each being an integrant molecule. * The faces at this end are all fractured ones. DO TAB XCVE, Div. 2. kmitative. Tus variety of sulphate of barytes has obtained the name of cauk among the miners; for what reason I do not know. It has also been called terra ponderosa. The sort here figured is very frequent in Ecton mine, Staffordshire. It is not uncommon in other places, but of a less regular sphee- tical form. It is generally accompanied by carbonate of hime, fluor, galena, blend, iron and copper pyrites, &c., and is most frequently white. Sometimes it is coloured by exide of iron, and is then either yellowish, or mostly reddish. The specimen represented in the upper jigure came from Ecton mine, and is accompanied by calcareous spar and pyrites of various forms and hues. The internal structure is confusedly laminated, showing signs of crystalli- zation, arranged in the form of a sphere; these lamine are extremely close, and often confused, or so thin that no determinate form can be made out, having only the appearance of segments of circular plates, sticking edgeway by the side of each other: see the lottom figure: at other times they are the edges of plates with the faces usual to tabular sulphate of barytes: see tal. 72. The whule are 200 sometimes attached by a greater or smaller base, so as to be nearly detached spheres; at other times only half a sphere or less. At Buxton, Derbyshire, however, detached balls are found, not far under the surface of the common earth: see the three figures in the middle. They seem to be formed among loam, and partake of an ochraceous hue ; the edges are fre- quently more separated, and less regularly rounded. They have occasionally attached to them single cubic crystals of fluor in a decomposing state ; of which more hereafter. These are somewhat related to the celebrated Bolognian stone, which shines like phosphorus in the dark; and if heated red hot in a common fire, it is said to assume the same property. They are allied also to the liver-stone *, which has its name from its hepatic scent, derived from sulphuret of ammonia or liver of sulphur. Varieties are found in Great Britain, which, when rubbed, give nearly the odour of stink-stone: see tal. 38. * Found in Adrarium, in Scania. I7 q j Wer72.2309-Lubijhed By Jal Sowerby, Border TARB,., XCVITI. FERRUM arseniatum, Arseniate of Tron. Class 3. Metals. Order 1. Homogeneous. Gen. 6. Tron. Spec. 8. Arseniate. Div. 1. Crystallized. Var. 7. Primitive. Tuts arseniate of iron is one of the richest that has been seen hitherto; and what adds much to the beauty of the specimen is, that the lighter green cubes are accumulated in groups, forming threads, lying on darker ones, all of which are very pellucid. To add to the rarity of this specimen, we find extremely fine fibres of an oxide of iron? partly encircled by a band as it were of the arseniate, which re- lieves the reddish brown dusty appearance of the oxide; and this last, in return, relieves the glittering arseniate. The fibres of the oxide are so fine that it requires a high magnifier to see them; we could not discover any other than simple fibres. The top figure is of the natural size; R 202 the middle one, somewhat magnified; the lower are more magnified. The gangue is chiefly quartz, with various co- Joured ochres and some arsenical iron, or what has been called mispickel: see the metallic parts in the upper figure. This isone of the many fine specimens in Mr. Rashleigh’s collection. a am Vow" £2804. Pubbjhed Ev Ja! Sowerbs, Lendir: TAB. XCVIII. BARYTES. sulphata. Sulphate of Barytes. Class 2. Earths. Order 1. Homogeneous. Gen. 6. Barytes. Spec. Sulphate. Div. 1. Crystallized. Tue specimen from which this figure was taken is in the collection of Mr. Professor Hailstone at Cambridge, to whom it was presented by John Probart, Esq., of Cop- thorne near Shrewsbury, in whose interesting museum the Professor saw several other crystals of the same kind, but of larger dimensions, and understood that they were found in some part of Shropshire; but he had no opportunity of ascertaining any further particulars respecting their native beds, and situation in the earth. It is a valuable specimen, to show the nature of a crystal terminated on all sides, and independent, or not fixed on any gangue. This is not common to sulphate of barytes. it has only a few quartz crystals at the upper corner, as expressed in the figure. The modification is altogether singular, and is a variety not yet figured; we find it has 23 faces, some scarcely distinct. The crystal is lengthened parallel to the obtuse angles of the rhomb, and the upper primitive face, which shows the prismatic hues somewhat below the surface. It has little hollows as it were unsup- plied by molecules; this is the case also in other parts, RQ 204 giving the crystal a rough appearance. These hollows agree very well, when narrowly examined, with the shape of the nucleus. The general form will be better understood by examining the geometrical figure at the bottom, containing a firure of the primitive or rhomboidal prism: see tal. 70; allowing for the perspective, and conceiving the sharp angles as the obtuse ones, viz. the right and left hand angles ; the upper and lower faces and the four corners are primitive faces corresponding with the six faces of the nucleus. The four larger octangular faces are evidently parallel to the acute corners of the rhomb (allowing for the perspective). In their formation, the laminz are (as it were) arranged on the upper and under primitive faces, decreasing from the four acute angles of the nucleus from four obtuse angles ; the same also forming 2 long quadrangular faces at the left hand end, and 2 large hexangular ones at the other end of the geometrical figure coming in contact with the primitive faces at the corners, at an angle of about 123° with the upper or under primitive faces. Next to these, on the same angle of the nucleus, are two other 4-sided faces above and below, the larger at an angle of 140° 59’ 2” upon the primitive, and the smaller at one of 162° 2’ 44”. These may be distinctly seen on the top of the upper figure. The Cumberland specimens seem to have the face of 123°, which appears not to have been seen by Hatiy. Mr, Hailstone’s specimen has two small faces marked by dotted lines on the right hand front corner, and one on the right hand corner at the back, which agree with the faces y of Haiiy. This I have not seen in any other English specimen. 4 nied 1 ine ‘ Be > Weov? 7808. Pblified by Ja Sowerby Z aT TAB. XCIX. FERRUM sulphureum. Sulphuret of Iron; Iron Pyrites. Class 3. Metals. Order 1. Homogeneous. Gen. 6. Iron. Spec. 6. Sulphuret. Div. 1. Crystallized. Var. Octaédral, &c. Syn. Fer sulfuré octaédre. Hazy, v. 4. 69. Ocrazprat Pyrites is not so common as cubical Pyrites ; we have it however along with various substances, as calca- reous spar, limestone, coal, &c. The present figures are designed to show this modification from the cube passing into what Haiiy calls the cubo-octaédre, thence into the perfect octaédron. At the commencement of this change the corners of the cube are replaced by triangular faces—see the left hand figure—which, as the modification goes on, become planes of six sides each—see the middle figure—and at last the primitive faces are lost. These six-sided planes are reduced again to triangular ones, forming the octaédron. I am indebted to the late Lady Elizabeth Noel of Bath for the upper and right hand specimens. The first is the cast of a shell of the Trochus genus; and it should seem that the crystals are on the cast in place of the shell, as the rock 1s about the thickness of the shell from the cast, and isa mould of the outside of the shell. On the left hand side remains a bit of the rock, and on the right hand are exhibited the thickness and calcareous remains of the shells, sufficient to indicate the species to a conchologist, which appears to be 6 206 different from any shells of the present age. This is taker from another specimen which also came from Bath by fa- vour of T. Walford, Esq. The pyrites on this are octaé- drons, some of which have their solid angles slightly trun- cated. It nearest resembles Trochus niloticus Linn., but we do not consider it as that species. The cast of the shell on the right hand, of a golden hue, being covered with pyrites, generally deeply truncated, seems a species of Mytilus cut off in the manner of Donax denticulata Linn. The shell on the left hand seems to be a Tellina, and includes pyrites, chiefly of a cubo-octaédral form—see left hand botiom figure—as it were hermetically sealed in, and of course not discovered till the shell was broken. How these crystals came there may excite wonder ; but, were we sufficiently acquainted with nature’s operations, we should see every natural cause as well as its effect. This shell most nearly resembles Lister’s Tellina lata rugosa, tab. 390. f. 229. . These fossils are in great abundance above the sand quarries at Woolwich and Charlton, about nine feet from the surface of the hill, in a loose marly stratum, from one to six feet thick. How long they have been preserved there is not known ; they however will soon rot and decay after exposure to the air. The other sorts of shells are two species of Turbo, probably of the same date; these will also fall to pieces. Of oyster shells there is great abundance, which do not, to my knowledge, differ from those at present known, nor do they decay so readily as the others. There are other shells in this curious place, and in Lady Wilson’s park at Charl- ton, with specimens of which I have been favoured by her ladyship. I have gathered the more common ones myself. 3 200, Weour2 180%. Publjpeds ly Jad Sowedy, Loner TAB. C. CUPRUM oxygenizatum; var. cubicum. Cubical Red Oxide of Copper. Syn. Cuivre oxydé rouge cubique. Haiy, v. 3.557. Goop cubical crystallizations of Red Oxide of Copper are much rarer than octaédrons: see tab. 53. This specimen came from near Redruth in Cornwall. It is crystallized in distinct cubes sometimes, but oftener in rather irregular groups, yet with their edges and planes parallei to each other, seldom hike Fluor, tab. 73, or Galena, tal. 24, &c., which are generally more confused. It rarely forms large cubes, although I understand that some have been found a quarter of an inch in diameter. They are often truncated at their solid angles, forming the cubo- octaédre of Hatiy, ¢.63 and 71. The magnified figure re- presents a group somewhat like one on the specimen, which has a large cubo-octaédre at the left hand corner, and the rest consists of various sized cubes, and one or two of an- other group, showing that the different groups may stand in different directions, 208 These are more generally of a more beautiful Bohemian or Scotch garnet* colour than the octaédrons. We know of no difference in their substances. * Now called Pyrope, differing from the common garnet in colour, trans- parency, and in never being crystallized. It should seem also that they may be still further subdivided. SYSTEMATICAL INDEX TO VOL: lis CLASS I, COMBUSTIBLES. ORDER 1. HOMOGENEOUS. GEN. 7. Carbo Tab. Spec. 2, bituminosus Dw.1. crystallized — — 48 Spec. 3. oxygenizatus —~ — 49 Dw. 3.amorphous — — 50 ORDER 2. COMPOUND. Gen. 1. Bitumen Spec. 1. carburetus Dw.3.amorphous — — 51 Gen. 3. Soda Spec. 7. muriatum Dw. 1. crystallized —- — 22 Div. 2.imitative — — 22 CLASS Il EARTHS, Tab. metastaticg == — zquiaxi-lenticularis ferrifera-lenticularis Div, 2. iraitative stalactitica —. — sericea se gly! coralliformis —_ botryoidea feetida Div. 8, amorphous cretacea — — petrosa as — Spec. 6. fluor Dw. 1. crystallized primitiva — — cubica —— — — S8-sided — — ORDER 1. HOMOGENEOUS, Gen. 4. Silex Gen. 1, Argilla Spec. 1, durissima Dw. 1. crystallized — — 69 Gen. 3. Calx Spec. 1. nativa Dw.3.amorphous — — 1 Spec. 4. sulphata Div. 1, crystallized — — 67 — Div. 2, imitative plumosa — — Spec. 6. carbonata Dv, 1. crystallized primitiva — — lop) los} bo — ee ee Cow wrd mb ht xquiaxis — oa Spec. 1. quartzum Dw. 1. crystallized pumitivum — — dodecaédrum — Div. 3. amorphous — — Spec. analcimus Dw.1. crystallized — — Div. 2. imitative fibrosus _- — Div. 3. amorphous compactus Spec. granatus Dw. 1. crystallized primitivus, &c. — Gen. 5. Strontia Spec. 2. carbonata Dw. 1. crystallized — — 33 34 35 36 12 62 63 210 SYSTEMATICAL INDEX TO VOL. I. Tab. Gen. 6. Barytes Spec. 1. sulphata Div. crystallized primitive &c. — — tabular — — — Spec. 2. carbonate Div. 1. crystallized — — ORDER 2. MIXED. Gen. 1. Argilla Spec. 1. Marga — ORDER 3. AGGREGATE. Gen. 1. Quartzum Spec. 1. arenaceum = — — SOAR 2) Spec. 2. farcimen — =. Spec. 3. arenaceum calcareum CLASS Ill. METALS. 95, 96. 14 ORDER 1. HOMOGENEOUS. Gen. 5. Manganesium Spec. 1. oxygenizatum Div. 1. crystallized — — Gen. 6. Zincum Spec. 2. sulphureum Div. 1. erystallized tetraédrum &c. — Gen. 7. Stannum Spec. 1. oxygenizatum Div. 1. crystallized — — Gen. 8. Ferrum Spec. 2. suboxygenizatum Dw. 1. crystallized a fee Spec. 3. oxygenizatum Div.1.crystallized is Div. 2. imitative (foliated) ——) radiatum 3=— Spec. 4- phosphatum ceruleum Div. 3. amorphous — 86 Tab: Spec. 5. sulphureum Div. 1. crystallized cubical — — 29 30 octaédrat — — 99 Spec. 6. sulphatum Div. 2.imitative — — 23 Spec. 9, arseniatum Div. 1. crystallized cubical &c; — — 87 ———. 97 Gen. 10. Cuprum Spec. 1. nativum Div. 1. crystallized dodecaédral — 23 Div. 2. imitative arborescens — 25 dendriticum — 17 Spec, 2. oxygeuizatum Div. 1. crystallized octaédrum — — 53 cubicum — — 109 Spec. 3. carbonatum Div. 2. imitative byssoides | —— | 47 radiated — — 94 Spec. 5. sulphureum Div. 1. crystallized tetraédral &e. - 77 | | dodecaédral &c. 78 Spec. 8. arseniatum Dw. 1. crystallized octaédral &c. Gl —_— 32 hexangular plate 37 Div. 2. imitative amianthiform — 45 pee Lette 46 pencillated — — 93 Gen. 14. Argentum Spec. 1. nativum Div. 2.imitative — — 16 Gen. 15. Plumbum Spec. 2. phosphate Div. 1. crystallized — 84 Spec. 3. sulphureum Div. 1. crystallized primitive — — 24 Gen. 18. Aurum Spec. 1. nativum Div. 3.amoerphous — == 52 ORDER 2. MIXED. Gen. 1. Ferrum (oxygenizatum} Spec. 1. argillaceum — — Gh ALPHABETICAL INDEX Or PLATES, Ge. TO VOL. I. Tab. Page. ApamanTINE SPAY vere oepet /ejetoleiel =) ajejret 144 (8 SANGUAG TEE OB OE GUE OS Hp ab moe 169 PAT IKECISE he ota toh ahs / cis) aa Sree ies 1 PMU oO dala 6)us) a take oats aes 65 BMELD CL tebe a ieee haan ol shor ehe sneak evens W cotene 105 PENTRU MACIIG tata hits ieno 6 Sake araio: delays aps ayes 128 ASEAN CTLTAYS EE aa a SRN ERENT ae OYA 50| 123. 127 —————-— compact.........5........ 57 123 ADLOUS AN MUTAD yon). ioe e atae) 58 125 pe AIS 1 0 os benaey abs elds oh eeeie os 125 PAD OE ANCE tS cers. choy alae ce) ts Hes coo cats 39 PAREN MACE ca Mec sraalte oes «sierra: 37 AIP emiIMNALVUMNY {oe see Ce we ees os 37 _———_—. var. capillaceum .... 16 37 PAN OUD ce fac y ope LS 2s Re sia oa oy ao Marais gens 33 Aired (CALGATIETS 2 ert.) aie) sinless) c1o Stee 33 Aroilla durissima oc. . fs sce see ves cle 60 143, MRIS Semon one atom ove god 14 33 AGI UT MAUIVAUINIL, 2\5, 51% 1/9. <.5 « «1s s caer tos 52 1li B AIMIGCK.. itis oboe Ses eb wie eo cay clam 16 Bar olite vs 1m. oye wk eee Ais ci ae 157 BaTOSEIEHItC iis is, 5 woes deca: «218k cee eee 147.150 AV YVieGEARDOMALE. 5 6 ie 2's 2.5 < Sisley 15% Syl bis (a ee Nara trae 147.150 (Barytes, derared ye 015 ssls'-' 4/2 22 o's = ater 157 CapWOnatal cose fc. sree a eran: 76 157 CARUVOUALS OL Ee. 2 ots yet cee 76 157 ——— poisonous hepar of .......... 157 am SUIpHatA 2) ete es tt op ae 70—72. | 147--150. 95, 96.98 | 197--200. 203 212 ALPHABETICAL INDEX. Tab. Page. Barytes, sulphate of ...)....5.4. sete | LO sn) een 95, 99.98 | 197--200. 203 tabular). wi. were 149 Basalt ye eee cre a logehe sce Aare ene ee 123 Bath slime ne pesca. etsy aois Gicky oho de eievee 2 SS UOC ere cher eRe Ticks (a etcy Asi see 8 18, 19 Bitumenicarburetum Weiss sls Sale iicel sc 51 107 ——- Lithanthrax ....5........ Bit 99 Black=Sackep ee ei 0 Og ic eme wede ae ee, Me 153 Ble olan. iy NOLS SNC es over gate 55 Blende=khole: S20 0).)..0s suc eteme aioe 103 Blend eyes Be ee AN ce esha | 153—155 Bleyaerg braun ae 08 i ole caotneie + 173 = OUT ote iiauel ate miaheh stint sat ot oot aly ibid. SF UNNLEISSES) jie dey uncalss gnadiatae oatstr ie a 187 Bloodstone tice sich hey crane Meron ee 122 Blme=dolinte ica so Bas aon tamer cn anchors 55 Borax granatus ....... bitte ORRIN at oF ot Ql Bovey coal}... andere dae oie. 109 Braunstein? OR... SP SSP aie vod adey wien 177 Bailding hillstone.... 2) seo oe hea eee 82 Bar Frenele®...)..5 bee: ge eneodes® 90 C Cachalon ee be wkdaed walt ences 90 Caicedony he. Poh a a alae ake fa) id 90. 171 Corie) 7 Ga oe eo aan ee 2 Galx; ‘aerated sa Sian Mh een gee on ae 5 carbonataea.. 6b aser oe coaamne se 2 5 — var, equiaxi-lenticularis . 12 29 ——— si equlaiS ee ee ee 13 31 — —— — coralliformis ...... (e) 21 — st KCHEWACEA; fh hsin te syns 7 15 — ~————_ — _ ferrifera lenticularis . 62 133 — —— — lenticularis.:::::.. 3 13 Se ee ee OCHA nd as ess 38 81 ee) EES yn Seo 4 9 — ——— — margaritacea ...... 19 45 —— ———- — metastatica....:... 33—36 75—73 — —— — petrosa- .......... 8 79 17.163 — ———_ — _ primitiva.......... 3- 20 Feats 7. ae — SeVriC@a::.2..3522%3 5 lial — stalactitica:........ 6 13 Calx: fluor, oars). . |... sititid ci fetes 73 151 * The miners’ name for Galena. ALPHABETICAL INDEX. Rex Nuon vars cubicay chi eieieisecide's SS PHIMNVA SU iiene wm er rg a p ct p MARTEL) wieisctc te PG ATCA Agel a MUA OrTA: iN UMN Nutr AORYPEMIZACUS ©). Gain aa wa ve wats @arbonie: aed oas "8 Se oe Carbon, mineral, impregnated with bi- 5 RIAU VS Net areal orenavaro nats MOAT UIC ES CN ee ie ee HO peeeeemns COMMON: (505s cia se: sie sisiele ane PACT OR Wn suche dive 6 Oy cel nie Carbonatee she sie Fite eee LQUIAKCK: corey stalls eee ae, lentieulaine) sien aoe > CYAVEUSE: ae ew ewe Le FEETIMETEM A aa eee Pete ow ei eee ie formes déterminables . . QTOSSICLE 5 0%, 2) 0562 anes MNIVETSE hx etude ieee metastatique ........ PLIMUtIVE 65 66 be ee Auaté cubique 4.4.05 222422 cee 5 PLUMMITIVES, 02 ss 2. SRA AYOKCE Oe ne eesreevaness agowbdcel celia = trapezienne’- .°.. Maes Chlorophane ...... Pees Bh Bee ea Bie 49 141, 142 49 1 99 103. 105 106. 188 99 103 103 o2 131 ibid, 199 52 1.15 15 5 ibid, 31 133, 134 13 15 7:A5 81 5 15 9 75—78 7 25 59 25 49 141, 142 26 109 102, ibid. ibid. 104 102 ibid. 214 ALPHABETICAL INDEX. OL 8 on CII CA RV RN 48 ——— in upright prisms with rhomboidal bases * @oeo ee ee ce ee ee ee ee wo e@eorec es eecec te oe Be oe wee OP oOo] e@2eec ee ee ee © oo ewe Oe Oe ow eeeoc eco ee ee ee ee eo eee ew oe” -amianthiform ...... 45,46 ————- capillary .......... - in hexaédral laminze with inclined sides .......... earbonate/Of J. meee 2 04 ——— — Byssus-like ...... AZ Caleiform ores Ted a2 cia 6 sat TIALIVESA Rie & eens ee ee eae =larborescent. . 22 4205 cs. 25 =iCenanitaGal 12 Meee he 17 ore; malachite +". 0 an Bee =~ PEACOCK 51,5, s/ghe gis seeetee oxideioh mative sic eee - red, crystallized, crystal oetacdraly ieee Fe alent ays 53 plates, for engraving on, &c. PDILES 0. forester ie a alg SRI SWIPHUNEL bre... ee: o's einerees , un, and zinc, make brass...... SOMMU-AMMIONIS suns AA PA ek tan Cornndum, Ceylon) i... ees. sess -, imperfect from China...... —_——--, Scotch..............00.. 69 Se MATIC tee, Seen Ane cable hymn Crate compacte Via eve cree eis ws ele Greta Scriptoriay 726s. scl ¢ Cee Ser Srystal; mountain 0.6 Beier. tale pace de roche dodecaédre .......... HT VPP Pr Page. 104 99 101 102 ibid. ibid. 105 ibid. 104 102 Pies 79. 193 - 93.95 04 79 195 97 115 Al 57 4) 97 160, 161 115 95 115 ibid. 207 42 159—161 ibid, 42 29 140 145 143 146. 164 15 15 87 89 ¥ Rhomboidal coal (commonly called dice coal), in contradietinction te coals which do not break in rhombs. ALPHABETICAL INDEX. 215 Giyslal roe, oie, Hecker tc eneketor crevorarens Cuivre arseniaté lamelliforme.......... -- carbonaté vert soyeuse ........ meas Flat EP MAL WMS ey |v hor oncheuevoreachions ere -- oxydé rouge primitif .......... = PY BIC re Stee. Sy Stet teeta s os CUP AESEMIATUIN fe es ohh okey or shiv enreysn oe - —_ var... amianthiformis ———- carbonatum .............. Tae -- var. byssoides . —$——- mnatiVUM .... kee ee ———-- oxygenizatum, var. octaédrum ————— var. cubicum.. —- sulphuratum................ ee Diamonds’ Commish 33s. e ele ee oe MDOOLEM 2 ac sla ala ay cea eneIS VV CLC Ve sharers ocie eens aoe Dogs-tooth spaks....$.5..0: Ee hina ah Aart hist - ee es ee ral He PMMUMIET 12 5 ois a ao HS seme steimy magnetischer- si2s+:22222 , Spathiger +. accsvacece pst Etain oxydé....... the aie eet aes Se ey == OPPOSHE so dined fie tices sich V4 B Ines de spathiqne 9 .\55.15/2)52's as). ae pOMSAS Lem pepe: a stirs, wor sielera ray srcieeleis ’ On Q 2, = = @ oc tal e I] PONV AC HYeMAGEN Is 0). a2 dere majenies Omy ul earns ei afc s aie ole ae SULEAtG) 20 ee an staid datataa(s See (ok Eee Qu @ SUIT yt Sao a oa ads eee BRON Ra Tab. | Page. 79- 193 45, 46 | 03, 94,05 04 105 47 97 Aj 25 57 17 41 53 115 100 207 77,78) 159. 161 75.78 103. 106 87 ibid. ibid. 75.78 133, 134 139 135 130 117 53. 65 ibid. 67. 69 216 ALPHABETICAL INDEX. Ferrum argillaceum ............ proaele AVSEMIAUNIIN 6521 e6) ohcyeieyssenes ed iets Ccerule mmr ics Fhe youee soa feta oxygenizatum ...... Jesegeeyeveuere ——— _ —_____—_--- war. crystallizatum —— - -- — radiatum.... suboxygenizatum ...... cee cene S00) cr: ta Sl Sone ese) ree sulphureum ...... SERN SEA tesselare sods el eR: a IBELIEr=SteIT a hee Oak) ep Blintyds Re ee ad ae REET. Galena Sic. ae age a PSS a Pe GATTICE. Neh gkenst an a SN cane aoa? Garnets, Bohemians ct... wet c taco 1 RT) oR yy a es Sa is tn 8, WMA tse oalepoh-kes alelerere-e'o)6.« “Bee STs 7a 10701 (es Manas Se Sear Bet Pn as Bere ae Glass, manner of etching on ......... A ele CER OSH aihs bo oss crate a hala Glass kop Gar ne aac ete Ue han ERTOENE Drs Mais pe Naser car Haase Gold, gediegen 2... 0. voccceetcredes MALIME RE ieee Ns HM Sta Sead Aas did Granaty Ae oe YD haa aac. satiate ciate Grayeee ls Ms a Sea SO didis slulclaverd Grenson 5 nas Naik ea TES Re BE EE ay ey wn oi pews Gypsum Whee Poche eae sos cists! 68 52 141, 142 104 26 136 130 121 ill ibid. gl 185 Q1 83 128 50. 141, 142 141, 142 3 ALPHABETICAL INDEX. 27 Tab. Page. H TA even tehthtelss cs fy Gren Go SEs CORE eee Ra Dil —- DION Ha, 3-2 Gta BtANS Cue eee 130 FS IRON Waa IN el a ER IRE TS ore Dl la einanomoanGaee ous 6 cnlGu eon eee 138 Helmintholithus ammonites .......... 29 EVematites 5 wr aap ihe n lacy a 60} 121. 130 13 Gidnloilsecls fp Arn Bes ae eae eo 164. nome: 3. BE SVR eles BRU eee 09 ly alte yaar e ie lea ere rahe horse sie 124 I—J VEGee SVE TGS Se ae POMPE MA ee nM 164 “UBTE 5 DST Ry CURE es, Sapna iia eat tet ee eID 107 Bayete aise: eh asia tals epc chp age ibid WO CHASE tg AUR cee eA esac yell taispi 127 AGE aE AY Sora! We * VSR e CRES N feie CLR Na 51 ~ 107 AKOW GarseniatevOl i) sac cs cunts: A, SY OTF 181 in a calcined state mineralized by PRS NAME tay etenareuiels. c flv esoN tates eat 117 ———— ONE ABP IMACEOUS 4s