BAR 



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B A S 



terially impede their progress through 

 the water. Some very fine specimens 

 may be seen of them in the British 

 Museum. The barnacle is known by the 

 names Anatifer, and Pentelasmis. In 

 the arrangement of Cuvier the barnacle 

 is placed in the sixth class, namely, 

 Cirrhopoda, of Mollusca. Linnaeus com- 

 prised them all in one genus, Lepas, 

 which Brugieres divided into two. The 

 name anatifer, from the two Latin words 

 anas and fero, signifying duck-bearing, 

 was given to the barnacle from a ridicu- 

 lous notion, formerly entertained, that 

 they enclosed in an embryo state the 

 young of the barnacle duck. Sowerby 

 states that fossil specimens of this marine 

 genus are found in the calcaire-grossier, 

 of Paris, and in other similar beds. 

 Parkinson observes that anatifa Isevis 

 and anatifa striata are both said by Bosc 

 to be found fossil ; the latter is also said 

 by Gmelin to be sometimes found fossil, 

 but that he believes neither of these 

 statements to be supported by sufficient 

 authority. He, however, gives a re- 

 presentation of what he believes to be 

 a fossil barnacle in a flint stone which he 

 found in the gravel pits near Hackney- 

 road, and the opinion he first formed, not 

 only of its having derived its figure from 

 animal organization, but of its affinity 

 to the barnacle, received corroboration 

 from different specimens which he subse- 

 quently met with. Large bunches of 

 barnacles attached to pieces of wood are 

 frequently thrown up by the waves upon 

 our coasts. 



BA'ROLITE. (from (3api>, heavy, and 

 Xi#of, a stone, Gr.) Carbonate of 

 barytes. The Baryte carbonatee of Haiiy. 

 Barolite is found native, or it may be 

 artificially prepared. It was first dis- 

 covered native by Dr. Withering, from 

 whom it was named Witherite. Accord- 

 ing to the analysis of Dr. Withering, 

 carbonate of barytes consists of barytes 

 80, and carbonic acid 20. It is soluble 

 in dilute nitric acid. It is poisonous. It 

 occurs abundantly in lead veins, that 

 traverse a secondary limestone in Cum- 

 berland and Durham, and at Anglesark, 

 in Lancashire. 



BAROSE'LENITE. (from (3api>, heavy, and 

 selenite.) Heavy spar ; native sulphate 

 of barytes, or boroselenite. The Baryte 

 sulphatee of Haiiy. A mineral, found 

 abundantly in this and other countries. 

 It occurs both massive and crystallised. 

 The varieties of its crystals are very 

 numerous. It is of various colours, 

 white, grey, yellow, brown, red, green, 

 blue, and black. It consists of 66 per 

 cent, of barytes and 34 per cent, of 

 sulphuric acid. Its texture is generally 



foliated. When heated it decrepitates- 

 It is soluble in dilute sulphuric acid. It 

 is found in veins, in primary, transition , 

 and secondary rocks. 



BA'ROTE. A name given to barytes by 

 Morveau. See Barytes. 



BARYSTRO'NTIANITE. (from fiapvG, heavy, 

 and strontian.) This mineral has also 

 obtained the name of Stromnite, from its 

 being found at Stromness, in the island 

 of Pomona. Its principal constituent is 

 carbonate of strontia, of which it contains 

 nearly 70 per cent., combined with sul- 

 phate of baryta and a small proportion 

 of carbonate of lime and oxide of iron. It 

 occurs massive, of a greyish colour exter- 

 nally, and of a yellowish white internally. 



BARY'TA. ^ from flapvg, heavy, Gr.) 



BA'RYTE. }> Barytes has been also called 



BARY'TES. j ponderous spar, heavy spar, 

 and barote. The first account of the 

 properties, &c. of barytes, was published 

 by Scheele in his dissertation on Man- 

 ganese. It has obtained its name from 

 its great specific gravity, which is about 

 4, being the heaviest of all the known 

 earths. It was called barote by Morveau, 

 and barytes by Kirwaii. Barytes con- 

 verts vegetable blues to green. When 

 exposed to the atmosphere it attracts 

 moisture, and when water is 'poured 

 upon it the same appearances present 

 themselves as in the slacking of lime, 

 with the evolution of great heat, the pro- 

 cess being more rapid, and the evolution 

 of heat greater. Barytes is found in two 

 natural combinations only, with the sul- 

 phuric and carbonic acids, forming sul- 

 phate and carbonate of barytes. Nearly 

 all the compounds of barytes are poison- 

 ous, the best antidotes being dilute sul- 

 phuric acid, or sulphate of soda in solution. 



BARY'TIC. Containing barytes ; resem- 

 bling barytes ; having the properties of 

 barytes. 



BA'SAL. Arising from the base of some 

 other part. 



BA'SALT. (Said to be derived from an 

 Ethiopian word, basal, signifying iron.) 

 A variety of trap-rock of a dark green or 

 brownish black colour, composed of au- 

 gite and felspar with some iron and 

 olivine, the predominant mineral being 

 felspar. Basalt occurs, sometimes, in 

 veins or dykes, which traverse rocks of 

 all ages, filling up fissures or crevices, 

 and at others, in layers spread over the 

 surface of the strata, or interposed be- 

 tween them. Many modern lavas differ 

 so little from basalt, that it is unneces- 

 sary to adduce proof of the volcanic na- 

 ture of this rock. It often occurs in the 

 form of regular pillars, or columns, clus- 

 tered together ; or, in scientific language, 

 has a columnar structure, a character 



