BERYL. 



BETA. 



when the terminal edges are modified there will generally be found a 

 plane inclined to the lateral planes of the prism under an angle oi 

 119 58'. 



The crystals admit of cleavage in the four directions parallel to the 

 faces of the regular prism, that parallel to the terminal plane being 

 perfect, the others imperfect and more difficult to be obtained. The 

 fracture is conchoidal and uneven ; the lustre is vitreous, and it 

 possesses various degrees of transparency. According to Mohs the 

 hardness varies from 7'5 to 8, the specific gravity from 2'678 to 2732. 

 The following are its chemical characters before the blow-pipe, as stated 

 by Berzeliug. 



Alone it is not easily acted upon, but when thin fragments are for 

 a long time submitted to a powerful flame the edges become rounded, 

 and a colourless vesicular scoria is produced. The transparent varieties 

 become milky. 



With borax it forms a clear and generally colourless glass, which 

 effect is also produced by soda. With the phosphor salt it is with 

 difficulty dissolved without the formation of a silicious skeleton. 



Of this mineral we possess several analyses, of which the following 

 are three : the first being an Emerald from Peru, by Klaproth ; the 

 second a Beryl from Siberia, by the same chemist ; and the third a 

 Beryl from Broddbo, near Fahlun, in Sweden : 



Beryl. Beryl. 



Emerald. Siberia. Broddbo. 



Silica 68-50 66'45 68'35 



Alumina 1575 1675 17'60 



Glucina 12'50 15'50 13'13 



Oxide of Iron . . . I'OO 0'60 072 



Oxide of Columbium . O'OO O'OO 0'27 



Oxide of Chromium . 0'30 0"00 O'OO 



Lime 0'25 0-00 O'OO 



This species contains several varieties, of which the two known 

 among lapidaries under the name of Emerald and Aquamarine, or 

 Precious Beryl, are the most worthy of attention. These varieties, 

 though distinguished by some mineralogists as forming distinct 

 species, differ however only in colour, the term Emerald being applied 

 to those possessing the peculiar rich deep green so well known as the 

 emerald-green, while all the other varieties are comprehended under 

 the name of Beryl ; those which are clear, transparent, and possess a 

 good colour, present various shades of sky-blue or mountain-green, 

 being the Aquamarine or Precious Beryl. The colour of the Emerald 

 is attributed to the small quantity of green oxide of chromium which 

 has been found in the specimens from Peru ; while the varieties in the 

 tints of Beryl may be considered to be produced by admixtures of 

 the oxides of iron, the yellow being the colour of the peroxides of 

 iron, and the mountain-green and the various shades of blue being the 

 effect of varying quantities of the protoxide, to the presence of which 

 the common bottle-glass owes its tint. 



The following localities produce the finest Emeralds : The mines in 

 the Tunca Valley, situated in the mountains between New Granada 

 and Popayan, and not far from the town of Santa F<S de Bogota, 

 where, according to Humboldt, they are found in veins traversing clay- 

 slate, hornblende-slate, and granite ; the Heubach Valley, in the dis- 

 trict of Pinzgau, Salzburg, where they occur imbedded in mica-slate, 

 and are inferior in colour to those from Peru ; varieties have also been 

 lately found in some old mines in Mount Zabarah, in Upper Egypt, 

 from which spot the ancients are supposed to have derived their 

 emeralds. 



The varieties known by the name of Beryl are found principally in 

 Siberia and Brazil : in the former country it occurs in the granite 

 district of Nertschinsk and also in the Uralian and Altai Mountains, 

 sometimes in very large crystals, prisms having been found upwards 

 of a foot in length. In the granitic mountains of Odon Tchelon, in 

 Dauria, three very interesting mines occur at different elevations hi 

 the mountain ; in the lowest are found, irregularly disseminated 

 through a mass of semi-decomposed granite mixed with ferruginous 

 clay and nodules of Wolfram, prismatic crystals of Beryl of a greenish- 

 yellow colour, rarely exceeding one inch in length. Some hundred 

 feet higher occurs the second mine in a vein of micaceous clay, from 

 which the most valuable crystals are obtained ; their colour is of a 

 pale but pure green, and their size frequently considerable. The 

 third mine i situated in a vein of white indurated clay on the summit 

 of a mountain ; in this mine the varieties are usually of a pale greenish- 

 blue, but sometimes they are found of a pure but pale sky-blue. They 

 are here remarkably transparent. Imbedded crystals and massive 

 varieties are also found at Limoges, in France ; near Zwiesel, on the 

 Rabenstein, in Bavaria; at Fimbo and Broddbo, near Fahlun, in 

 Sweden; anil likewise in some of the tin-mines in Saxony and Bohemia. 

 An enormous specimen is also described in Silliman's ' Journal ' as 

 having been found at Acworth in New Hampshire, United States. 

 Its dimensions are stated to be 4 feet in length and 54 inches across 

 the lateral planes, and the weight to be 238 pounds. 



SJM . iiueiM ..f l',,;ryl have also been found in several of the primary 

 districts of Ireland ; those from the granite of the Mourne Mountains, 

 in the county of Down, are the finest. In this locality they are asso- 

 with topaz, black quartz, felspar, and mica. In Scotland it is 

 found in the granite at Rubeslau quarry, near Aberdeen, and also in 

 l>rok' i the sand of the rivers of that county. 



HAT. HIST. 1>IV. VOL. I. 



The value of the Emerald depends not only on its size, colour, and 

 brilliancy, but also on its being free from flaws, by which this gem is 

 frequently greatly deteriorated in the eye of the jeweller. The follow- 

 ing is the rate at which varieties of a fine colour and free from fissures 

 may be procured, as stated by Beudant : 



A stone of 5 grs. from 100 to 120 francs. 

 8 240 francs. 

 15 1500 

 24 2400 



BETIYX, a genus of Fishes of the order Acanthoptcrygii, and 

 belonging to a little group of the family Pcrcida;, in which the species 

 possess more than seven branchial rays, whereas all the other genera 

 included in the first division of this order (in which division the 

 cheeks are not defended by indurated plates) possess seven or less. 



Cuvier, in his ' Regne Animal,' mentions three other genera 

 belonging to this group : namely, Holocentrum, Myripristis, and 

 Trachichthyt. 



The other characters of Beryx are as follows : Ventral fins, with 

 one spine and ten soft rays ; the back furnished with but one slightly- 

 extended fin, and some indistinct small spines on its anterior edge. 



Several species are fossil. B. ornatus occurs in the Chalk of Sussex. 

 Mantell figured it, under the title of Zeug Lewtsiensis, in the ' Geology 

 of Sussex." Two other species occur in the British Chalk. 



BESHAN, a name given to the Balm of Mecca, the produce of 

 Baltamodmdron Opobateamum. [BALSAMODENDRON.] 



BE'TA, a genus of plants belonging to the natural order Chenopo- 

 diaeta, among which it is known by its having large succulent roots, 

 and a green calyx united halfway to a hard rugged nut. The species 

 are found in Europe, the north of Africa, and the western parts of 

 Asia ; four are cultivated as esculents, the others are mere weeds. 



S. vvigarit, Common Beet, is said to be found in a wild state along 

 the whole of the sea-coast of the Mediterranean, and in Egypt ; it is 

 however chiefly known as a plant cultivated in gardens, for its carrot-like 

 sweet and tender roots. Several sorts are mentioned by writers on 

 gardening, varying in the size, form, colour, and sweetness of their 

 roote : of these however two are much more worth cultivating than 

 the others, namely, the small red variety and the long yellow variety ; 

 they are the most delicate, the sweetest, and have the richest colour 

 when served at table. 



B. altiuima, Mangel Wurzel, is a much larger and coarser plant 

 than the Common Beet, from which it is principally known by ita 

 roots being marked internally with zones of red and pink or white. 

 Ita native country is unknown ; by some it is reckoned a mere variety 

 of the Common Beet, but this is scarcely probable, considering that it 

 is permanently reproduced from seed ; others state that it is a hybrid 

 between the Common and Chard Beet, our third sort, of which however 

 there is neither proof nor probability. Mangel Wurzel is an object of 

 extensive cultivation for feeding cattle; its leaves afford a very 

 nutritious food for all kinds of live stock, and the roots, from their 

 extreme sweetness, are by many farmers considered the most valuable 

 of all the agricultural plants upon which cattle are fed in winter. 

 Independently of their use for cattle, Mangel Wurzel roots have been 

 extensively employed in the manufacture of sugar. They are still 

 employed in France in the manufacture of sugar ; and an attempt 

 has lately been made in Ireland to use them for the same purpose. 

 For this, the common red and white Mangel Wurzel will perhaps be 

 found best suited in this country, in consequence of its hardiness, and 

 the great weight per acre which it will afford ; but the French have 

 preferred a perfectly white kind, which is said to exceed the former 

 in nutritive properties, in the proportion of two to one ; they also 

 grow a sort with white roots and a purple crown, and another white 

 within, and yellow on the outside. The yellow Field-Beet, which has 

 been a good deal cultivated in this country, ia apparently a variety of 

 B. vulgaru, and is too unproductive in most situations to bear 

 comparison with the others. 



B. eycla, Chard Beet, is inferior to the two last in the size of its 

 roots, but is remarkable for the thickness of the ribs of its leaves, 

 which are white, yellow, green, orange coloured, or deep crimson, in 

 different varieties. It is cultivated like the Common Beet, but the 

 leaves only are used in soups, or their ribs are cut out and stewed 

 like sea-kail. They have however an earthy taste, which is not in the 

 power of cookery wholly to remove, on which account they are little 

 esteemed. The French call this species Poire"e a Gardes. It is said 

 to have been introduced to France from Portugal ; but its native 

 station is unknown. 



B. maritima, Sea-Beet, unlike the three last, is a prostrate plant, 

 with numerous entangled branches and a tough woody root. It is 

 found abundantly on many parts of the southern coast of England, 

 and is a common European shore-plant, preferring a chalky soil. Ita 

 eaves are small, ovate, deep green, crenelled, rather sharp-pointed, 

 lat, succulent, and placed on long stalks. Its flowers are green and 

 arranged in spikes, each being subtended by a small leafy bract. It 

 s a perennial, and one of the most valuable plants known for spinach ; 

 ito leaves when dressed are extremely delicate and well-flavoured, and 

 easily reduced into that pulpy substance which constitutes the great 

 merit of good spinach. It thrives in a garden without any sort of 

 care, and is rather a handsome plant when growing among rubbish, 

 r or ita leaves are a particularly rich green, and nut liable to be scorched 



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