Plate 

 24.5. 



NATURAL HISTORY. 



Plate 



iin 



ing the concentric layers of which it 

 is compofed 

 Fig. 20. Perpendicular fedion of a bulbous root 



MINERALOGY. 



246. Infcribed Natural History, Plate I. 



Fietu of Mount Mina, from Spallanzani' s Work. 

 This is a general view of Mount ^tna, the adjacent 

 country and the fea; and is intended to (hew the 

 effefts occafioned by the eruption of the volcanic 

 matter at different times. A points out the loftiell 

 furamit of the Mount. H is Nicolofi, and marks 

 the Mount Roffo or Red Mountain, formerly a 

 plain, but in 1699, a new vertex opened in it, 

 and difcharged the dreadful torrents of lava which 

 overflowed the land, till reaching the fea, it formed 

 the promontory of lava in the fea extending as far 

 as letter Y. G, near this new opening of jEtna, is 

 the mountain Montpelieri or Montpileri 

 Various other interefting fpots are marked in the 

 plate, for which confult the article .^tna, Mount. 



246. Infcribed Natural History, Plate II. 



A Vie'w of the Crater of Mount JEtna. 

 AAA One edge of the lava of 1787, which 

 iffued from the upper crater. B B the circum- 

 ference of the crater, with its cleft C C through 

 which the internal part is difcernible. D the 

 flat bottom of the crater. E the aperture in the 

 bottom through which the larger column of fmoke 

 F F arofe. G G is that part of the edge of 

 the crater from which its internal part is beft 

 feen. H H is the fmaller column of fmoke to 

 the north-eafl:. Vide article Mount .ZEtna for 

 further explanation 



247. Infcribed Natural History, Plate V. 



Vie-w of Mount Vefuv'ius, as feen from the Bay of 

 Naples. From an original il<etch made in 

 the year 1797, by R. Duppa, Efq. 



248. Infcribed Natural History, Plate IV. 



View of the Crater of Mount Vefu-uius. Drawn 

 by the fame hand, and at the fame time as 

 the preceding. 



249. Mineralogy, Plate II. 



Bafah. The Mountain of Aifa, called La 

 Coupe, or the Col d'Aifa, near the village 

 Entrague, in the Viverrais, above the tor- 

 rent of Volant 

 This plate affords an example of the formation of 

 bafaltic columns, and illuftrates the hypothefis of 

 the Huttonian fyftem, according to which the 

 bafaltic matter has been originally of volcanic ori- 

 gin, and while in a fl;ate of fufion cafl: out of the 

 crater of the mountain. In its progrefs this lava 

 has formed a wavy channel down the mountain 

 iide. According to St. Fond, this is the moft 

 remarkable and beft charaderized crater in all the 

 Viverrais. The ends of the columns may be 

 diftmftly feen before the bafalt reaches the river. 



GEOLOGY. 



250. Geology, Plate I. 



Fig. I. The upper figure in this Plate exhibits the 



dip, dyke, fault, flip, trouble. See. de 

 fcribed and referred to in the article 

 Coal 



251. Geology, Plate II. 



Fig. I — 10. Seftions of various Strata 





252. Geology, Plate III. 



Fig. I. Strata: being a ilietch of the arrangemen 

 of the ftrata through England, by Mr 

 R. Bakewell. Lat. 54° 35' to 54° 45', 



2. Seftion of the fl;rata through part 1 



Dorfetfhire and Devonfliire, b^' Mr. R 

 Bakewell 



3. Perpendicular ftrata 



4. Horizontal ftrata 



5. Inclined ftrata, confifting- of greywacke 



clay-flate, compaci felfpar, porphyry 

 fienite, trap, clink-ftone and granite, val. 

 ley of Long Sleddale, Weftmoreland - p 



6. Undulate ftrata : ftiewing the wavy ftruftuW 



of the beds of flate, called ftiillet, ii 

 Devonfhire 



I 



253. 



h 



h 



Fij 



254. 



Geology, Plate IV. 

 Fig. 1,1. Metallic veins exemplified, with a « rider,?. 1 r 

 &c. ; and alfo the interfeftion (or « cut. 

 ting-oflP') of metallic veins 

 2. Columnar and amorphous bafah, inicr. 



fetted by bafaltic dykes 

 4. Lime-ftone broken and inclofed in bafalt, feer 

 in a bafaltic rock on the coaft of Antriiri 

 Whinftone dykes, or bafaltic veins, pafling' 

 through chalk, and changing it into mai^ 

 ble — under figure 4. 

 [See article Geology. Suppl. Vol. XXXIX.V 



Addenda to the Geological Illujlrations . 

 Plate Ichthyolite, or Ichthylogical Remains. 



Mineralized remains, orimprefllons of fifhes, 

 on black ftiiftofe flate, found at Ifleben, 

 in Germany 



255. 



Fossils, Extraneous, Plate I. 



Fig. I. Mineralized remains of an encrinus, Encrinus 

 liliiformis, or " ftone lily," in relievo, on 

 a flab of ftone 



2. Tranfverfe feftion of the lily-head 



3. The lily-head half broken through tranf- 



verfely 



4. Bottom of the lily-head, fhewing the pe- 



duncle by which it is connefted to the 

 main ftem of the encrinus 



Fii 



CRYSTALLOGRAPHY. 



I 'C 



256. Lettered Crystallography, Plate I. 



•f^'g- I — 7- Various forms of the cryftals of adaman- 

 tine fpar 

 8 — 16. Ditto of felfpar 



262. Lettered Crystallization, Plate VII. 

 Fig. 27. The Octohedron, regularly formed 

 13. The Tetrahedron, regularly formed 



'C 



