BLU 



146 



BOA 



The air is supplied from the lungs of the 

 operator, or by bellows or bladders adapted 

 to the purpose : bxit modifications of the 

 blowpipe are made, whereby jets of oxy- 

 gen, hydrogen, or the two gases mixed in 

 the due proportions, are substituted for 

 atmospheric air. When the two gases are 

 used, the proper apparatus constitute 

 what is called the oryhydrogen blowpipe. 

 The blowpipe is an invaluable instrument 

 to jewellers, mineralogists, chemists, 

 enamellers. glass-workers, &c., as it 

 affords them instantaneously a heat equal 

 to the strongest heat of a furnace. 



BLUB'BER. I. The fat of whales and 

 Other sea-animals, of which train-oil is 

 made. The blubber is the adcps of the 

 animal ; it lies immediately under the 

 skin, and over the muscular flesh ; it is 

 about six iuehes thick, but about the 

 upper lip it is from two to three feet in 



thickness. 2. The sea-nettle is also 



called the sea-blubber. See MEDUSA. 



BLUE'-BOXNET. 1. A small bird common 

 in Britain : so called from a blue spot on 



its head. 2. A species of centauria 



(q. v.) is so called from the colour and 

 shape of its flower. 



BLUE'-C AP, a species of the salmon tribe, 

 so called from the blue spots on the head. 



BLUE DYES are indigo, prussian blue, 

 logwood, bilberry (Vacciniitm myrtillus), 

 elder-berries (Snmbucits niyra], mulber- 

 ries, privet- berries (Ligustrwn vulgare], 

 and some other berries, whose juices 

 become blue by the addition of a small 

 portion of alkali, or of the salts of copper. 



BLUE'ING, the process of heating iron 

 and some other metals until they assume 

 a blue colour. The blue colour depends 

 on a film of sub-oxide. 



BLUE-JOHN, a name given by the mi- 

 ners to fluor-spar, called also Derbyshire- 

 spar. 



BLUE PIGMENTS. The blue pigments 

 found in common are Prussian-blue, 

 mountain-blue, Bremen-blue or verditer, 

 iron-blue, cobalt-blue, smalt, charcoal- 

 blue, ultramarine, indigo, litmus, and 



blue-cake. The molybdates of mercury 



and tin, the hydrosulphuret and the prus- 

 siate of tungsten, the ammonuret of cop- 

 per, and the silicale of copper, may be 

 useful in particular cases. 



BLUE-STOCKING, a pedantic female : 

 one who has sacrificed the characteristic 

 excellencies of her sex to learning. The 

 term originated with Mr. Stillingfleet, 

 who constantly wore blue stockings, and 

 whose conversations on literary subjects 

 were highly prized in certain female 

 evening assemblies afterwards denomi- 

 nated blue-stocking chilis. 



BLUE VITRIOL, sulphate of copper. 



ULTTF, a high headland presenting a 

 precipitous front. Hence a ship is said to 

 be bluff-headed wheii her stern is upright 



or nearly so ; and bluff-bowed, when her 

 bows and broad are flat. 



BLUN'DERBUSS, blunder andD. bus, a gun. 

 A short gun with a large bore, so as to 

 contain a number of small balls, and 

 intended to do execution without exact 

 aim. 



BLCXK, a name in Scotland for calico, 

 or that species of cotton cloth manufac- 

 tured for being printed ; hence bhmker, a. 

 calico-printer. The word is a trivial ap- 

 plication of the word Hunk, dull, this 

 species of cloth being denominated by 

 weavers " heavy work." 



BOA. 1. The Latin name of a popular 



eruption. 2. An old name of the Ines 



venerea. 3. A boa-like ruff worn by 



ladies. It takes its name from its great 

 length. 4. The name of a genus of rep- 

 tiles belonging to Cuvier's tribe of ser~ 

 pentia or true serpents. It is in this genus 

 that are found the largest serpents on the 

 globe. Certain species attain a length of 

 30 or 40 feet, prey on dogs,deer,and even 

 oxen, which they manage to swallow 

 entire, after having crushed them in their 

 folds, and covered them with saliva. The 

 species, of which the boa constrictor and 

 the anaconda are the most celebrated, are 

 natives of the hottest latitudes of South 

 America. The great serpents of the old 

 continent belong to the genus pythoti, to 

 which however, the name boa appears to 

 belong as a matter of right, having been 

 so named, according to Pliny, because 

 they sucked the teats of cows (3ous, 

 a cow). Certain large Italian serpents 

 appear to have been first called boas, and 

 subsequently the name came to signify 

 any very large serpent, and was but le- 

 cently restricted. 



BOAR. In the manege, ahorse is said tt 

 boar when he shoots out his nose, raising 

 it as high as his ears, and tossing it in the 

 wind. 



BOARD, Sax. Germ. Sw. lord. 1. In 

 nautical language, the line over which a 

 ship runs between tack and tack. To 

 make a good board, is to sail in a straight 

 line when close hauled. To make short 

 boards, is to tack frequently. To board, is 



to enter a ship by force in combat. 



2. A body of men constituting a quorum 

 in session ; a court ; a council ; e. g. a board 

 of trustees ; a board of ofiicers ; a board of 



commissioners. 3. In carpentry. See 



DEAL. 



BOARDING- JOISTS, joists in naked flooring 

 to which the boards are fixed. 



BOARDINO-PIKE, a pike used by sailors 

 in boarding an enemy's vessel. 



BOASTING, in stone- cutting, the paring of 

 a stone with a broad chissel and mallet. 



BOAT, Sax. Sw. bat, Germ, bot, Sp. bate. 

 A vessel propelled by oars, or rowing. 

 Boats differ in construction and name ac- 

 cording to the services in which they are 



