185 



OROGRAPHY. 



ORRERY. 



160 



cipitated waters they store up in their interior and exhaustless reser- 

 voirs, whence springs are continually issuing, which unite and form 

 those streams that fertilise the plains, or, collected into mighty rivers, 

 favour the transport of commodities and facilitate the intercourse 

 between the ocean and the interior of the continents. The influence 

 of mountains on local climate is all-powerful, and depends \ipon the 

 direction in which they lie as regards the sun's course, their height, 

 their position on the surface of the globe, their proximity to or remote- 

 ness from the sea, the winds they arrest or give passage to, &c. 

 Mountains have moreover a climate of their own, or rather a great 

 variety of climates. Thus, in ascending from the sea towards the 

 summit of the Andes, almost every kind of climate is passed through, 

 nearly as completely as if the traveller were to proceed from the 

 equator towards the pole. At an elevation of about 16,000 feet on 

 the Andes under the equator, we reach the lower limit of perpetual 

 congelation ; and mountains in that region which exceed that height 

 have their summits covered with eternal enow. The line of perpetual 

 congelation is, however, far from being parallel with the general surface 

 of the earth. It approaches that surface as it advances towards the 

 poles, but the laws which determine this line are still imperfectly 

 known. [CLIMATK ; Ssow, PEHEN.NIAL.] 



The limits of perpetual congelation, as ascertained from the stability 

 of snow on the mountains, are subject to vary with the particular 

 aspect of the mountains and other local circumstances. Thus, gene- 

 rally speaking, the snow-line is highest on the south side of mountains 

 in the northern hemisphere, and vice rerid ; but this is not always the 

 case ; and the line of perpetual snow is much higher on the northern 

 than on the southern side of the Himalaya mountains. Mr. Pentland 

 states that the limit of perpetual snow is at an elevation of 1 5,800 feet 

 on the mountains of Vilcanota in South America, which are as far 

 south as 14 33'. 



The fact of the cold increasing as we ascend mountains is due in 

 part to the greater rarity of the atmosphere in the higher regions, and 

 to their greater distance from the radiated heat of the plains ; never- 

 theless the particular aspect of various parts of mountains as regards 

 the sun, and the conformation of the higher valleys, greatly modify 

 the culd of particular places ; and a much greater heat is sometimes 

 experienced in a high valley than is felt in one much lower down. To 

 this circumstance is due in part the seeming anomalies that are met 

 with in the habitation of plants, many being found at heights where 

 they would be little expected. 



Though mountains are such striking objects, and, when contemplated 

 only with respect to their absolute elevation above the sea, appear to 

 be enormous protuberances on the earth's surface, they are very incon- 

 siderable when compared with the whole mass of the globe. The 

 i Me parts of the earth, at least those where population is most 

 dense, and in which human industry is most concentrated, all lie 

 within a few hundred feet above the sea, which may be regarded as a part 

 of the true surface of the sphere. But even the height of the loftiest 

 mountain.-, which w alxmt tire miles, is only about one eight-hundredth 

 part of the radius of the earth. In books of travels we often find the 

 distance mentioned at which a particular mountain is visible. As 

 assertions of this kind are sometimes loosely made, the following rule 

 will serve for roughly estimating the distance at which a mountain 

 of known height can be seen from the surface of the sphere : multiply 

 the square root of the height of the mountain in feet by 1*2247 ; the 

 t will be the distance in miles at which the mountain is visible. 



With regard to the heights of Mountains it may be observed that 

 they vary considerably. Some authors, however, regard every eminence 

 below 1000 feet as a hill. Since the application of the .barometer to 

 the admeasurement of heights, there are few mountains of any import- 

 ance, in Kurope at least, whose elevation above the sea is not now 

 known and registered. A list of the principal mountain heights on 

 the globe would till a volume. It may be sufficient here to give the 

 heights of the principal peaks of some of the more important chains. 



\[ont Blanc, highest point of ;Uie Alps, and of Europe, 

 1",71I feet ; Mout Perdu, Pyrenees, 10,994 ^lonte Corno, Apennines, 

 9523 ; Lomnitz, Carpathians, 8799 ; Sneehetta, Dovrefield, Norway, 

 8122; Mulhacen, Sierra Nevada, Spain, 11,483 ; Puy de Sanci, Auvergne, 

 France, 6200; Mont Mezin, Cevennes, FrUnce, 5795; Mta&, Sicily, 

 10,870; Olympus, Greece, 9754 ; Vesuvius, 3917. 



Britiih Ifln ml*. The greater number of the heights about to be 

 stated, are derived from a table of the ' Altitudes above the mean 

 level of the sea of the stations composing the principal Triangulation ' 

 of the.Ordnance Trigonometrical Survey of Great Britain and Ireland, 

 given in the account of that triangulation recently produced by Captain 

 A. R. Clarke, R.E., under the direction of Colonel Sir Henry James, 

 li.lv, F.K.S., Superintendent of the Survey, London, 1858. The 

 altitudes of a few stations but little elevated above the sea, are in- 

 I for comparison. Fractions of a foot are either omitted, or 

 reckoned as an entire foot, except in heights below 1000 feet, in which 

 they are given. 



Si-;i Fell, highest point in England, 3229; Helvellyn, 

 8055; Skiddaw, 3038; Cross Fell, 2928; Cheviot, 2669; Coniston 

 Fell, 2575; Ingleborough, 2373; Great Whernside, 2310; Malvern, 

 1396 ; Mendip, 979'2 ; Inkpen Beacon, the loftiest summit of the 

 chalk formation, 972'8 ; Leith Hill, 967 ; Fairlight Down, 5837 ; 

 Beachy Head, 632'4; Lundy Island, 466; St. Paul's Cathedral, top of 



cross, 417'9; Severndroog Castle, Shooter's Hill, ground, 406'4; Epping 

 Poorhouse, 371-2 ; Greenwich Observatory, vane, 214; Ordnance Map 

 Office, Southampton, 78; York Minster, ground, 53; Ely Minster, 

 ground, 51 '6 ; Norwich Cathedral spire, ground, 197. 



Wales. Snowdon, highest point in the principality, 3590; Cam 

 Llewellen, 3471 ; Cader Idris, 2959 ; Great Orme's Head, 683'1. 



Scotland. Ben Nevis, highest point in the British Isles, 4406 ; Ben 

 Macdui, 4296 ; Ben Lawers, 3984 ; Ben Lomond, 3192 Schehallien 

 3564; Ben More, Mull, 3185 ; Ben More, South Uist, "2034. 



Ireland. Carran Tual, Kerry, highest point in Ireland (?), 3412, 

 doubtful ; Slieve Donard, 2788 ; Nephin, 2638 ; Mourne Mountains 

 2493, doubtful ; Howth, 555. 



Asia. Mount Everest, Nepaul, 29,002 (highest mountain known, 

 measured by Colonel Waugh) ; Kunchin-junga, Sikkim, W. part, 28,178, 

 E. peak, 27,826 ; Dhawalagiri, Nepaul, 26,862; Juwahir, 25,670. These 

 are peaks of the Himalaya. Ophir, Sumatra, 13,840; Mowna Roa, 

 Sandwich Islands, 13,700; Egmont, New Zealand, 8S40 ; Italitskoi, 

 Altaian chain, 10,735; Ararat, Armenia, 17,212; Arjish, Anatolia, 

 10,000?; Olympus, Anatolia, 6500 ; Lebanon, Palestine, 9517; Awatska, 

 a volcano in Kamtchatka, 12,000 feet. 



Africa. Kilimandjaro, lat. 4'0' S. in the true Mountains of the 

 Moon, 20,000 ?; Abba Jarat, Abyssinia, 15,008; Geesh, in Abyssinia, 

 15,000 ? ; Peak of Teyde, Teneriffe, a volcano, 12,205 ; highest peak 

 of Atlas chain, 12,000, and perhaps more ; Table Mountain, 3816. 



America. Aconcagua, Chile, (highest point in America?) 23,910 ; 

 Illimani (the richest gold mountain of Peru), 21,140 ; Chimboraco, 

 Andes, 21,424; Antisana, 19,136; Cotopaxi, 18,775; Pichincha, 15,931 ; 

 Popocatepetl, Mexico, 17.720 : the last four are volcanoes. Mount 

 St. Elias, U.S., 17,850; Fremont's Peak, Rocky Mountains, 13,570; 

 Mount Washington, Appalachians, 6428. 



Mount Terror, 13,384 ; Mount Erebus, 12,367 ; both in the antarctic 

 lands. 



The particular history of important ranges of mountains, as ALPS, 

 ALTAI, &c., will be found in GEOO. Dry. under their names, respectively, 

 or under those of the countries to which they belong. 



OROSELONE. [ATHAMANTIN.] 



O'RPHICA, certain works falsely ascribed to Orpheus, which em- 

 bodied the opinions of a class of persons whom Miiller thus describes : 

 " These were the followers of Orpheus (of 'Ofxputol) ; that is to say, 

 associations of persons who, under the guidance of the ancient mystical 

 poet Orpheus, dedicated themselves to the worship of Bacchus, in 

 which they hoped to find satisfaction for an ardent longing after the 

 soothing and elevating influences of religion. The Dionysus, to whose 

 worship these Orphic and Bacchic rites (TO 'OpQutk aAeo>fi>a /tal 

 BaKx'Ki, Herod, ii. 81) were annexed, was the Chthonian deity Diony- 

 sus Zagreus, closely connected with Demeter and Cora, who was the 

 personified expression, not only of the most rapturous pleasure, but 

 also of a deep sorrow for the miseries of human life. The Orphic 

 legends and poems related in great part to this Dionysus, who was 

 combined, as an infernal deity, with Hades (a doctrine given by the 

 philosopher Heraclitus as the opinion of a particular sect) ; and upon 

 whom the Orphic theologers founded their hopes of the purification 

 and ultimate immortality of the soul. But their mode of celebrating 

 this worship was very different from the popular rites of Bacchus. 

 The Orphic worshippers of Bacchus did not indulge in unrestrained 

 pleasure and frantic enthusiasm, but rather aimed at an ascetic purity 

 of life and manners. The followers of Orpheus, when they had tasted 

 the mystic sacrificial feast of raw flesh torn from the ox of Dionysus 

 (wjuotpfryfa), partook of no other animal food. They wore white linen 

 garments, like Oriental and Egyptian priests, from whom, as Herodotus 

 remarks, much may have been borrowed in the ritual of the Orphic 

 worship." (' History of the Literature of Greece," where the reader 

 will find a full account of the Orphic theology.) 



Of the Orphic writers the most celebrated are Onomacritus, who 

 lived under Pisistratus and his sons, and Cercops, a Pythagorean, who 

 lived about B.C. 504. Works ascribed to Orpheus were extant at a 

 very early period. Plato mentions several kinds of Orphic poems ; 

 but he intimates that they were not genuine. Aristotle speaks of 

 them as the io-called Orphic poems (ra xa\ovneva). In later times all 

 manner of works on mysteries and religion were ascribed to Orpheus. 

 There are also Orphic poems later than the Christian era, which are 

 difficult to be distinguished from those of earlier times. In Fabri- 

 cius's ' Bibliotheca Grseca,' there is a list of the writings ascribed to 

 Orpheus. [ORPHEUS, in BIOG Div.] 



ORPIMENT. [ABSEXIC.] 



ORRERY. There are four planetary machines to which distinct 

 names have been given, corresponding to the phenomena they are 

 intended to exhibit, and which, when combined so as to derive their 

 motions from a common origin, constitute what is now generally 

 understood by an orrery. These machines are the Planetarium, the 

 '/' //"</<in, the Lunarian, and the Satellite machine. The planetarium 

 is a mechanical representation of the orbital motions of the planets 

 about the sun, either in circles or ellipses, and with angular velocities 

 either uniform or variable, according to the quality of the instrument. 

 The tellurian and lunarian, when connected in their improved form, 

 exhibit the motion of the moon about the earth and that of the earth 

 about the sun, and the principal phenomena which accompany the 

 changes in their relative positions, such as the succession of day arid 



