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VESUVIUS, a volcanic mountain, situated in the with its importance in hypothetical reasoning on kingdom of Naples, about six miles to the eastward this subject. of the capital. By the ancients it was called Mons In taking a general view of the external features Vesevus, or Vesbius, and in the earlier ages of an of Vesuvius, we are in the first place struck by its tiquity, it was famed for the luxuriance of the ve remarkable separation into two very dissimilar getation with which its sloping sides were covered, parts; Vesuvius, properly so called, a cinerous cone as it also is in modern times, except in those spots rising from an irregular plain, situated at no less laid waste by recent streams of erupted lava. On than 2400 feet above the sea, and Monte Somma, a three sides, the mountain overlooks the rich plain, craggy range of rocks, the precipitous side of which termed from its exquisite cultivation, and the dili- is formed into the segment of a circle, and presents gence of its peasantry, with equal propriety the its concavity towards the cone of Vesuvius, which Terra di Lavoro, and the Campo Felice, while on
it flanks to the northward for a considerable extent, the fourth, it descends more abruptly to be washed its own north side sloping gradually down to the by the waves of that splendid expanse of water, to plain of the Campo Felice. It is similar, in many which it adds so high a charm, the Bay of Naples, respects, to the remarkable hill of Salisbury Crags its base here being covered by a connected chain near Edinburgh, if we conceive the perpendicular of large villages, forming a stretch, perhaps almost face of the latter to have a concave instead of conunexampled, of many miles.
vex horizontal projection, and instead of the debris In regard to geological position, several impor- which form the steep slope to the westward, a plain tant facts are to be noticed; and in the first place, be conceived to extend from the base of the precipi. the whole tract of country, within several miles in tous rock till it joins the cone already mentioned. every direction landward of Naples, which has all Monte Somma appears undoubtedly to have been the same general constitution as that small portion the primeval point of ejection, though the conjeccalled the Phlegræan fields, must be considered as ture of some authors, that the present concavity a formation subordinate to its main feature, Mount formed the wall of a part of the original crater, Vesuvius, as owing its existence to essentially the seems extravagant, as the circle of which it is a same phenomena, and as an actual superposition of segment would have had a circumference of many a tract of country upon the pre-existent chain of miles. Some traces of what may have been the ori. the Apennines, which probably was at one period ginal crater may be observed in the course of this washed by the sea. The western limit of the Bay precipitous range near its western extremity. The must then have been the Monte Massico, not far face of rock there presents a remarkable section, from Mola, instead of the island of Ischia, which the main body being traversed by dykes which purnow terminates it, the eastern limit or the promon sue contorted courses, and frequently merge into tory of Minerva remaining constant, which gives or cross one another; they are of a different species an opening more than double the present one, and of rock from the basis, and may probably owe their the extreme depth of the bay, full fourteen miles origin to fissures made by the subsidence of the greater. The whole volcanic formation of which upheaved pre-existent rock, and filled up by a new Vesuvius forms the focus, reposes therefore upon species of lava at the next eruption. See Saussure the secondary limestone of which the Apennine in the Geneva Transactions, vol. ii.; Sir James Hall range is here formed; and of this we have various in the Edinburgh Transactions, vol. vii.; Hamildirect proofs, the most remarkable of which is the ton's Campi Phlegræi, and the Edinburgh Journal frequent projection of calcareous masses from the of Science, vol. ix. p. 191. The extreme height of crater of Vesuvius, either in an unaltered or a mo the Somma is 3703 feet. dified state; we have therefore the conclusive cer. At the western extremity of the Somma, rises an tainty, that between the volcanic focus and the point, elongated tufaceous eminence, named Monte Canof eruption, there exist calcareous strata. The taroni, on which at an elevation of 1971 feet, slands proximity of this volcano to the sea likewise de. the well known hermitage of St. Salvador, and serves notice, as following the general law pointed which is said to have been thrown up by the erupout in the article PhysicAL GEOGRAPHY. "Volca- tion of A.D. 79, when the whole features of the noes," it is there remarked, “ seem in general to volcano seem to have been changed, and when the be situated near the sea-coast, and rarely or never present position of the cone probably first became in the interior of large continents. Catopaxi, in the point of emission. This spot is protected from South America, is perhaps, of all volcanic moun the effects of streams of lava which often pass near tains, the most distant from the ocean, and yet it it, by a valley on each side, which serve to guide is only 140 miles distant from the shores of the Pa- the torrent in different directions; one of these is cific.” This is one of the few general facts recog. called the Fossa di Faraonte, the other Fossa nised in connexion with the theory of volcanoes, Grande; Fossa being the name here for these deep and ought therefore to hold a place commensurate and narrow ravines with which Vesuvius abounds,
the latter of these is interesting from the vast abun- portion of summit was carried away, the crater has dance of simple materials which it affords.
been, according to general computation, no less The cone, or Vesuvius properly so called, next than three miles and one-third in circumference, demands attention. Its height is liable to conside, and 1500 feet deep; being probably the largest in rable variation from the explosive effects of erupo existence. This confirms the view given under tions which have been known to carry off at once the article PhysicAL GEOGRAPHY, (Vol. XVI.), 800 feet of perpendicular height of the summit. that, generally speaking, the size of craters is inThe Abbe Nollet in 1749 found the height above versely as the height of the mountains to which the sea to be 3120 French feet, while Della Torre in they belong; even the case of Pichincha, which has 1752 gave from his very imperfect measurements a crater a mile in diameter, there quoted as an exwith the barometer only 1677 feet, a singular proof ception, we now see outdone in the comparatively of the enormous errors which at that period might diminutive example of Vesuvius. The American be committed without immediate detection. The volcano is no less than four times as high as that of first good observation we have is that of Saussure, the Bay of Naples, or near 16,000 feet; Mount making the height 3659 French feet, which is very Etna, which has an elevation of 11,000 feet, had in interesting, by showing, as Humboldt has remarked, 1769 a crater only 2} miles in circumference, and that this level is more constant than we are apt to that of the Peak of Teneriffe, which has a height of imagine. Shuckburgh found the edge of the crater above 12,000 feet, is only 300 feet long, 200 broad, from which the lava of 1776 flowed to be 3692 and 100 deep. French feet = 3935 English. The point, which The edge of the crater is narrow and precipitous, Saussure measured was on the N.W. side of the sloping internally and externally so fast, as to leave crater, and from a post which was fixed upon it was but a small ridge to walk upon. As to height, it is named La Rocca del Palo. In 1805 Gay Lussac very irregular, the northern point being 500 feet found this point 3757 English feet, and Lord Minto higher than the southern. The depth of the crater in 1821, 3963, and at that time, forty-nine years below the lowest edge, is probably little less than from its first measurement, it was carried away by 1500 feet, from which some idea of the true size of the great eruption. To methodize the results with this vast chasm may be formed. The southern side as much accuracy as the nature of the operations presents so moderate a slope inwards, that without in general warrants, we give the height of the any peril, the traveller may descend till within about Rocca del Palo by different observers, in toises 500 feet of the bottom, where he is stopped by a merely (= 6.3947 English feet) from a late work of precipitous crag; in the opposite direction it is so Humboldt's. *
steep, that we cannot descend above a few paces.
Various, indeed, are the modifications which the
Toises. crater has assumed under different stages of volca1773. Saussure (barometer)
pic energy. Previously to the first recorded erup1794. Poli, do.
606 tion of A.D. 72, the summit exhibited, according 1794. Breislak, do.
to Strabo, a level plain, interspersed with rocks and 1805. Gay Lussac, De Buch and Hum
caverns, which were rightly interpreted, as bear. boldt, do.
ing marks of previous imflammation. Before the 1810. Brioschi (trigonometry)
638 great eruption of 1631 took place, which succeeded 1816. Visinti, do.
622 to a long period of repose, the crater exhibited the 1822. Lord Minto (barometer)
621 most deceptive marks of quiescence; it was then 1822. P. Serope, do. slightly uncertain 604 5000 paces round, and 1000 deep; in the bottom 1822. Monticelli and Covelli
624 was a plane where cattle grazed, and the banks were *822. Humboldt, do.
629 clothed with abundant forests, in which wild boars
took shelter, and afforded sport to the lovers of the There is an appearance of greater elevation dur. chase. The sloping path which led to the bottom ing the latter part of this period, which Humboldt is said to have been three miles long. Three small thinks may amount to 12 toises, to be considered a lakes existed there, of which, according to the reproof of gradual internal elevation.
port of contemporary writers, one was warm, anThe proportion of the cone of ashes to the total other salt, and the third bitter. It appears from height is in Vesuvius į nearly, whereas in the vol. the curious old representation of the mountain at cano of Pichincha, it is only io, and in the Peak of this period, copied into Mecatti's account of Vesu. Teneriffe so low as 22.1 The mean slopes of volca. vius, that the Monte Somma was covered with trees nic cones are, according to Humboldt, from 32. to to the top, as was also the base of Vesuvius. In 42.; the mean slope of Vesuvius between the sum 1660 the crater was so shallow that it was easy to mit and the Atrio del Cavallo, is probably equal to descend to the bottom, where a small cone was the highest of these values. The base of the cone raised by the immediate action of the volcano. In is about 2480 feet above the sea.
1755, the bottom was only 23 French feet below the The crater by which the cone of ashes is trun. edge, and from the centre rose a parasitical cone cated, has varied in character and dimension very 80 or 90 feet in height, with its own proper crater. much, according to the state of the volcano. Sub. How different these conditions were from the presequently to the eruption of 1822, when so vast a sent one, the dimensions already given will show.'
• Tableaux de la Nature.
† Humboldt's Personal Narrative, I. 207.
In order to convey a general idea of the features mitage, plunged into the boiling abyss of lava, and of this volcano, we shall give a brief account of the met a fiery grave. Once more descending from ascent, which is a matter of no difficulty, and may the tufaceous eminence to the plain, we leave to the easily be accomplished by ladies.
left the Monte Somma, and “ Fossa di Faraonte,' There are different tracks by which the moun into which flowed the lava of 1785, and which di. tain may be ascended, but that universally preferred vides it from Monte Cantaroni, and set our faces is by Resina, and it alone we shall describe. This towards the cone of Vesuvius. village lies at the base of the mountain near the It is impossible to convey any impression of the sea-shore, and is about six miles east of Naples. state of this broad plain to those who have not viHere the traveller may think himself fortunate if he sited similar scenes. The amorphous mass of stony can secure the perso: al attendance of the elder Sal matter deposited by the last great eruption (1822) vatore, one of the best guides who can be met with has an appearance of sterility which no other rocky for any such expedition; asses are usually taken to formation presents; and for this plain reason, that diminish the labour of the ascent. For some way upon these natural causes of gradual but sure dethe road is simply rugged and stony, bounded by gradation have been working for thousands of years, high walls inclosing those extensive vineyards while here the newly moulded matter is ejected unwhich produce the admirable Lacryma Christi of formed and intractable as when it so lately existed this vicinity; currents of lava will occasionally meet in the bowels of the earth. The small scale of arthe eye of the traveller, and on the right hand he tificial penetration of the strata at which human will remark an unfortunate house, one half of which labour has arrived, can convey no idea of their prihas literally been swept away by such a stream, meval form: the difference lies in the comparative whilst the other has been left entire, as if to tell the synimetry of our mining operations as well as in tale. Farther on, cultivation in a moment ceases, the trifling extent of surface they present; but this and all the luxuriance of nature and of art com valley consists of several square miles, and the enbined is exchanged within a few yards for a degree tire western portion is buried under this stony inof obdurate sterility in the one which bids defiance undation, hard, black, and rugged, sometimes to all the ameliorating efforts of the other. In a swelling into craggy eminences with narrow caword, we have reached the western extremity or vernous hollows between, or occasionally flowing embouchure of the Atrio del Cavallo, and we see in a thinner stream over the flat-bed prepared for it stretched before us the combined streams of the by the pre-occurrence of a tremendous shower of eruptions of 1767, 1771, 1819 and 1822. The last ashes, above which it has formed blistered cavities, is not here so strikingly repulsive as higher up the into which shoot spicular masses of the same dark valley, as we shall presently describe; that of 18!9 intractable material. The only variety with which is remarkable for the peculiar ropy form which it the eye meets in this great plain, is here and there has assumed, being nothing else than the effect of an ejected mass of many cubic yards content, dissuccessive waves of scoriaceous matter forcing up charged from the mountain with such explosive the imperfectly solidified substance of the preceding force as to be driven far from the base of the cone: ones; hence it has acquired the appropriate name all else has but a symmetry in horror. Nature here of “Lava Corde.” Near it may be seen rudely in- wants the majesty and elevation of rocky cliffs, or termixed tabular masses; these have been produced the rich coating of verdare, or the more interest. by the insinuation of a liquid stream below a thin ing struggle of vegetable luxuriance with an arid but solid crust of lava which it has shattered, and soil,—although but little removed from the fertile then recombined the fragments. A few lichens on slope of the hill and the vast expanse of the highest the lava of 1767, are all the marks of decomposi- cultivation which environs its base, these beauties tion which it yet exhibits, and those on the current only contrast the more with the dark, cold, monoof 1819 are little better than microscopic; yet even tonous lava of which the distorted forms seem to these are farther advanced than some other lavas in partake of mobility, were we not assured by our the Bay of Naples which have lain exposed for cen senses that it were the work of centuries to reduce turies. We next reach the Monte Cantaroni al the rugged configuration of this siliceous rock. ready mentioned, which presents a steep ascent; the Arrived at last at the foot of the cone of ashes, highest point of this huge protruded mass of tufa is the traveller must leave his mule or ass, and trust occupied by the hermitage of St. Salvador, where to his feet in ascending that fatiguing, though in the monks live, who rather lead the life of public the present state of the mountain, short ascent. An cans than eremites.* It is to be observed, that active man may accomplish it in thirty minutes, coming to Monte Cantaroni at all, is quite out of the though not without great labour, from the sinking direct line of ascent, for we must again cross the and sliding of the volcanic ashes. His trouble, Atrio del Cavallo; but besides having the benefit of however, will soon be overpaid by the spectacle some species of road, the traveller who wishes to which awaits him on reaching the summit. And see the mountain, will do well to make this digres- first he will naturally look inwards towards the sion. Leaving St. Salvador, we pass near the crater at which he has at length arrived. Its vast + Cratere del Francese,” where in 1819 an unfortu- magnitude, the ruggedness of its extreme edge, the nate Frenchman, after living three days at the her- appalling abruptness of the precipice from the
On all the three occasions on which the author of the present article ascended Vesuvius, he reached the hermitage in about an hour and a half from Resina. Vol. XVIII.-PART I.
summit of which he first obtains his view, the loud men predominate in numbers: whether the task be and repeated echoes which the shrill voices of the to scale the frozen summit of Mont Blanc, or grap. guides excite through the cavern, and the curling ple with the embryo thunderbolt at the very forge smoke rising from the abyss, often concealing by of Vulcan; or the easier feat of scratching initials its dense volumes the remote recesses, and not un on the Ball of St. Peter's, -in every act of vain-gloaccompanied perhaps, with internal boiling of the rious temerity the English name is pre-eminent. igneous fluid, the chance ejection of stones, or the From the edge of the crater the distant view is occasional fall of rocks, the noise of whose descent almost equally worthy the traveller's attention is responded to by a hundred cliffs, all makes the in surprising contrast with the spectacle of its in. scene one, the first impression of which is so noble, terior:—there the rudest elements employed in so striking, as perhaps is not to be renewed. But the laboratory of nature, the unformed heap, the let him examine the structure more closely. In the chaotic confusion, the groaning or thunderous late state of the mountain (we speak of the years sounds as of Nature's throes:~here robed in her 1826-7), he might without the shadow of danger fairest forms and hues, displaying all the beauties descend two-thirds of the depth of the crater, by of recondite arrangement, and refined collocation of walking round a semi-circumference of it till he parts; the riches of her different kingdoms comarrives at its south-eastern point. There the in- biped to form as it were a model of inartificial perternal side, instead of presenting the abrupt preci- fection. At sunset especially the scene may be pice of its opposite extremity, shelves gradually most fully appreciated; the further beams of the inwards, aided by the much reduced elevation of great luminary as he sinks behind the remote shore its edge, which differs more than 500 feet from the of Gaeta, gild the distant waves of the Tyrrhene N.W. point. Here we may descend till we reach Sea, and invest the more abrupt points of the Itala precipice 500 feet in height, which separates us ian shore with a halo of misty splendour. Nearer from the bottom; and from this lone and unfre. the eye, they throw long shadows from higher emiquented spot we may at leisure survey nature in nences in the Bay of Naples, the island of Ischia some of her most remarkable forms. We tread with its once volcanic summit, formerly much more amidst thick beds of sulphur, the crevices of which to be dreaded than the now active Vesuvius; the often emit steamy spiracles rapidly condensed by hill of the Camaldoli; the humbler ridge of Pauthe chillness of the air, which is frequently great silipo. The ancient craturs of Averno and Agnaeven amidst these subterranean fires. The shades no, now occupied by lakes, demonstrate their true of colour which the sulphur beds present, are most form by their deepening shadows, the domes and varied and beautiful, from the palest straw colour, spires of Naples, and the old grey turrets of the where the pure yellow is diluted with ine white de Castel St. Elmo receive, and part with the declin. posits of decomposed lava, and occasionally of sul- ing solar ray,—and whilst on the left, the towerphate of alumina, up to the rich orange, which the ing hills of the promontory of Minerva, which form intermixture of arsenic, forming red and yellow or the eastern wing of the Bay, blaze in the broad expiment, occasionally presents. But grander scenes panse of sunshine, the distant Apennines behind the and sterner formations withdraw the attention of spectator as he faces the setting luminary, sink in the observer from the mineral world immediately the greyness of the twilight, and are soon lost in beneath his feet. He has but to raise his eyes to the dewy mists of the horizon. see the distended jaws of this great abyss stand in The phenomena of eruptions are in all volcanos all their ruggedness before him. Huge misshapen perhaps, very similar in a general view. Precedcrags rise on either hand, only their salient points ing earthquakes, subterranean noises, drying of conceal the remoter trendings of that volcanic plain wells, occasionally retirement of the sea, intimate which stands poised over unfathomed caverns, the the near approach of the catastrophe, and these are laboratories of Cyclopian energy. The plateau of succeeded by heaving and splitting of the mounthe crater is indeed but a crust, of which upon any tain, stillness and cloudiness in the air, accompanexcess of volcanic explosive force below, we have ied with a highly electric condition, which imparts abundant proof by the formation of miniature cra to the eruption some of its most extraordinary acters, through which may be distinctly heard on cessory phenomena. The explosive force from besuch occasions, the boiling noise of internal agita- low having opened a rent in the crater, a vast distion, and the rattling of stones, elevated from the charge of gaseous fluids follow, and though not unpit, with the constantly succeeding columns of often accompanied by boiling water in streams, smoke which are the consequence. Nature seems Vesuvius more frequently discharges showers of to have completely barred the volcanic plateau from dry impalpable volcanic dust, so fine as to be susthe access of mortal foot, in the present state of the tained a considerable time in the higher regions of mountain, yet the hardihood of strangers some the atmosphere, where having attained the height times induces them to descend by means of ropes at which the continued force of gravity and the di. these tremendous natural ramparts, with the great minished density of the air overcome the projectile danger of detaching masses of rock in the course momentum, the thin tall stream accumulates and of their descent. In this, as in all other enterprises spreads, having something of an umbrella form, or of which empty vanity in personal achievement is more accurately, that of the Italian pine (Pinus Pithe only excitement, we regret to add, our country. nea) to which it was first compared by Pliny, and
for which this mountain has ever been remarkable.* We must next very briefly notice the more imThe dusty particles then descend over a vast extent portant mineral productions of Vesuvius, confining of country, in a thick shower. It rarely happens ourselves to those of great extent and volcanic ori. that the crater is in a state to afford a ready over- gin. These may be divided into lava, breccia, tufa, flow of lava, and therefore from the simple princi- and volcanic dust. ples of hydrostatic pressure, that fluid bursts for it of a few of the external forms of lava we have self a point of emission near the base of the moun already given some notice. The really ornamental tain, and frequently elevates a parasitic cone. Thus lavas are chiefly found in the Mount Somma, and the lava of 1794 (ihat dreadful eruption which last constituie the remarkable cykes or veins to which overwhelmed Torre del Greco) issued from a crack we have also referred; they consist of a compact at the base of the cone, on the Pedamentina, about basis imbedding many beautiful and perfect cryshalf a mile in length according to Breislak, and 100 tals of leucite, a mineral, nearly, if not altogether, yards wide. In the eruption of 1760, no less than confined to the volcanoes of Italy: they are called fifteen mouths opened on the southern side of the partridge-eyed lavas, and have a beautiful appearmountain, raising as many cones, but the number ance. The Vesuvian lavas, for the most part, are of which was soon reduced to seven, and finally to hard and compact, and frequently approach in apfour, the height of one of which is 200 feet. Again pearance to a perfect identity with some of our in the great eruption of 1822, several small cones greenstones and basalts. Hence it is much used for were raised in the Atrio del Cavallo, belween Ve- paving, and the road between Naples and Portici suvius and the Hermitage.
is a perfect specimen of this application. It is Referring for more detailed accounts of particu. quarried from the couleè of 1794, near where it lar eruptions, or of their general features, to the flowed into the sea, and here a striking tendency works of Hamilton, Breislak, Della Torre, Mecatti, towards the assumption of prismatic forms may be and Scrope, we may mention the connexion which observed, and it is even probable that excellent ca. has been supposed to exist between Vesuvius and binet specimens, having the columnar structure, other volcanic emissaries. This question is a very might here be obtained; nothing indeed can more important one, yet is still involved in considerable perfectly resemble a quarry of basalt; and the chain doubt. Breislak, who had the best means of judg- is so complete through the medium of the lava of ing, strenuously denied it, f but we must suspect Capo di Bove near Rome, and the extinct volcahis judgment to have been biassed by preconceived noes of Auvergne, that the question of their simi. opinions, from the general conception of the re- larity of origin is probably for ever set at rest. The verse which prevails respecting the connexion at varieties of lava found in Vesuvius is very great, least of Vesuvius and Solfatara, a sentiment which and not less than twenty-two very distinct ones we ourselves have had the means of confirming, and have been enumerated in the Monte Somma alone. which Sir Humphry Davy, a philosopher whose In general, however, they are rough, opake, and temperate judgment must ever command respe without lustre, very rarely indeed presenting the even for his bypotheses, expressly countenances. vitreous lustre. Hence obsidian is one of its most He observed the Solfatara on the 21st February uncommon products, though met with in conside1820, two days before the eruption of Vesuvius was rable quantity in the neighbouring island of Ischia; at its height; "the columns of steam," says he, it is only, we believe, found in small ovoidal cavi. “which usually rise in large quantities when Ve- ties, principally confined to the leucitic lavas of the suvius is tranquil, were now scarcely visible, and a Monte Somma, and from that point of ancient piece of paper thrown into the aperture did not rise emission the small quantity of pumice which is again, so that there was every reason to suppose found in detatched masses on the mountain, seems the existence of a descending current of air.”I It also to have proceeded; these two minerals being might however be supposed, that the connexion of probably very nearly allied in their formation. two volcanoes so nearly approached as Vesuvius Lava highly cellular is not an unfrequent producand Etna, would be more defined than it appears to tion of Vesuvius, and small spheres of it are frebe. Among 50 eruptions of the former, and 48 of quently ejected along with volcanic sand, and by the latter, occurring since the Christian era, the their lightness reach great distances. The cavities following are the nearest coincidences.
are occasionally coated with muriate of copper, as VESUVIUS.
in specimens from the “Cratere del Francese." 1694. March 12. 1694. March to December.
In the crater, lava exhibits a very different form; 1754. December 2. 1785. March 2.
the action of heat and moisture, but especially the 1759. August 3.
1780. May 18. 1787. October 31. 1737. July 28.
acid vapours which are abundantly evolved, soon 1798. June.
effect the disruption of those affinities by which the 1799. February. 1799. Jupe.
compact condition of the rock was maintained. 1809. December 10. 1809. March 27.
The most powerful agent is sulphurous acid, which 1811. October 12. 2
1911. October 25. December 31.S
at the same time, forming a neutral salt with the 1819. May 27. 1819. November 25.
iron, which is by far the most abundant colouring • That the phenomena of the “ Cenere" or showers of ashes depend upon no extraordinary principles, is illustrated by favourable eximples of the ascent of material particles of smoke in the air. We remember to have witnessed a very interesting confirmation of this near Edinburgh. Just behind the cone-like summit of a trappean mass in the eastero Pentland range, a quantity of brush wood had been set on fire. The air was remarkably calm and clear, and the beautiful column of smoke rose clear and defined with the craterlike eminence of trap rock just in front, then spreading on all sides where the cold increased, and the specific gravity of the air diminlabed, it bore a most persect and interesting resemblance to the majestic Vesuvian pine, Voyage Physique dans la Campanie, ii. 70. | Phil. Trans. 1828.
Daubeny on Volcanoes, p. 216.