BITTER VETCH BLACK-BREASTED REDSTART. 



and therefore depends as much upon natural causes, 

 as any other occurrence. 



BITTER VETCH is the Orobus of Tournefort, a 

 numerous family of the tare kind, mostly indigenous to 

 Europe. The orobus belongs to the Diadelphia class 

 and Decamlria order of Linnaeus, and to the natural 

 order Leguminoste. Generic character : calyx of five 

 teeth, the upper ones shorter and deeply divided ; 

 style round at top, and downy; pod roundish. There 

 are above thirty species of this genus divided into 

 three sections according to the composition of their 

 pinnated loaves as one-paired, many-paired, &c. 

 They are all pretty flowering plants : tho O. vcrmis 

 in gardens, and the O. tuberosus on our heaths, are 

 universally admired. 



BITUMEN. This term includes a considerable 

 ran<je of inflammable mineral substances. They are 

 of different degrees of consistency, from a thin fluid 

 to a solid ; but the solids are for the most part lique- 

 fiable at a moderate heat. Bitumen, as we have 

 already stated under ASPHALTUM, was formerly em- 

 ployed to a considerable extent in the arts of domestic 

 life. The Egyptian, after the lapse of thousands of 

 years, may still be said to preserve his identity in our 

 museums by the agency of this mineral, and when 

 the swathing clothes are unrolled many of the bodies 

 have been found in a high state of perfection. Bitu- 

 men is either elastic or compact ; the first of these is 

 of various shades of brown. It is found in abundance 

 in the Odin mine near Castleton in Derbyshire, in a 

 secondary limestone. 



Compact bitumen is of a brownish black colour ; 

 one variety may be impressed by the nail, and is 

 called maltha ; another is very brittle, and is in com- 

 merce called asphalt. On the banks of the Dead 

 Sea, and in the neighbourhood of the latter body, is 

 found a species of stone called " nuissa" by the Arabs, 

 which on attrition exhales an intolerable odour, and 

 burns like bitumen. It is of a jet-black colour, and 

 takes a fine polish. Maundrel saw pieces of it two 

 feet square in the convent of St. John in the Wilder- 

 ness. The inhabitants of that country employ it in 

 paving mosques, churches, and other places of public 

 resort. The natives of Bethlehem affirm that it is 

 endowed with powerful antiseptic virtues, and brace- 

 lets of it are worn by attendants on the sick as an 

 antidote against disease. Bituminous shale, which 

 forms the Brandschiefer of Werner, is of a brownish 

 black colour, and occurs in rocks of the coal forma- 

 tion, where it frequently alternates with and. passes 

 into slate-clay, and also into coal. It is also found 

 in the coal districts of our island, and in several 

 parts of the north of Europe. See PITCH, COAL, 

 MINERAL. 



BIXINEyE. The Arnotto family. A natural 

 order of dicotyledonous plants, containing six genera 

 and upwards of twenty species. The order is by 

 some included under the Flacourlianece. It is nearly 

 allied to the Cistinece and Homalineae. 



Its botanical characters are : Sepals or leaves of 

 the calyx varying from four to seven, with an imbri- 

 cated aestivation ; petals five, sometimes wanting ; 

 stamens indefinite, inserted on a disk ; anthers two- 

 celled ; ovary superior, sessile, one-celled ; style 

 single, or in two or four divisions ; fruit, a many- 

 seeded, single-celled capsule or berry. The plants 

 included in the order are trees or shrubs, generally 

 smooth and having alternate leaves with pellucid 

 dots. They are chiefly tropical exotics, found in the 



505 



hotter parts of America" and in the Mauritius. They 

 are not remarkable for their beauty, or for the useful 

 purposes to which they are applied. 



Their properties will be best shown by the follow- 

 ing examples : The chief genus (whence the order 

 is named) is called Bixa, a term derived from the 

 American name of the plants. The red pulp which 



Bixa. 



covers the seeds of the Bixa Orellana yields the sub- 

 stance known by the name of arnotto. It used to be 

 denominated Terra orellana, or orleana, and is called 

 by the French, rocou. The seeds are separated from 

 the pulp by maceration in hot water, and the pulp is 

 then made into balls or cakes, which when dried con- 

 stitute the arnotto of commerce. Good arnotto is 

 soft to the touch, and dissolves entirely in water. It 

 is slightly purgative arid stomachic, and is used in 

 Jamaica and other warm countries as a remedy for 

 dysentery and disorders of the kidneys. Dyers form 

 with it the colour called aurora, and when mixed 

 with lemon juice and a gum it forms a crimson paint 

 with which the Indians adorn their persons. By the 

 Spaniards it is used for the purpose of adding to 

 the colour and flavour of chocolate and soups. In 

 Gloucestershire and other counties it is employed to 

 colour cheese, and in Holland butter is dyed with it. 

 The bark of the tree is made into ropes in the West 

 Indies, and the wood is used for the purpose of pro- 

 curing fire by friction. The other genera of the 

 order are, Ludia, Lcetia, Prockia, Banara, and Azara. 

 The bark of Ludia heterophylla and sessilijlora has 

 emetic properties. The azaras are Chilian shrubs, 

 with fragrant flowers not known in the gardens of 

 Europe. 



BLACK-BREASTED, or TITHYS RED- 

 START (Phcenicura tithys. Motacilla erythaca, 

 Linnseus. Sylvia tithys, Temmirick.) This is a 

 ^common bird in Germany, Prussia, and the east of 

 Europe, becoming gradually more and more scarce 

 towards the west, and in Britain has only been 

 discovered very lately. It is about the size and shape 

 of a robin ; the whole upper parts to the rump are 

 bluish grey ; the base of the bill, region of the eyes, 

 the sides of the neck, throat and breast, black, 

 margined in the winter with ereyish edgings, which 

 gradually disappear in the spring ; middle of the 

 abdomen greyish white ; flanks and sides blackish 

 grey ; quills blackish ; the secondaries and tertials 

 slightly margined with dull white ; rump and tail 

 bright reddish rust colour ; the two middle feathers 

 of the latter dark brown. In the female the whole of 

 the body is of a uniform yellowish grey, the quills 



