41t 



s/.i: riiwiiK.it. 



itur.sn MAKIXI;. 



bunting at the mould when the boiling metal descend* inU> it), the 

 whole U carefully lowered into the pit, and closely rammed down w itli 

 and. *c., to prevent it* moving ; the hannls for the metal to enter 

 nd the venU (or the escape of the air being of ooune kept perfectly 



ning.the 



When the metal it ready for running, the uiuth of the furnace, 

 which U pUonl rather above the level of the top of the pit, U opened, 

 and the brume descends tmm*^Hfjy into the mould. The mixture 

 of metal preferred by the above-mentioned sculptor u that used for 

 casting guns, to which be adda about SO per cent, of pure cop- 

 per, extracting from 3 to 4 per cent, of tin. In modern practice 

 It u not, by many of the most successf ul founder*, considered import- 

 ant to cast the whole work at onoe: on the contrary, in case of 

 aoeidenU, which however are of very rare occurrence, there U an 

 advantage in being able to repair parta ; and the process of burning, 

 successfully ado|>tod by Westmacott and othera in the largest works 

 (and which U found a great improvement on the ancient method of 

 aoldering), render* the joined portion* even firmer or stronger at their 

 point of junction than the general body of the cast. A description of 

 the method of ting adopted in other foundries, differing HOUR what 

 from the above, will be found iu the Introduction to Mr. D. Wyatt's 



Treatise on Metal work.' 



This abort history of bronze casting is purposely limited to iu 

 iirfisiinii to the Fine ArU ; and though, in speaking of celebrated pro- 

 ductions or artists, it has been considered advisable to introduce inci- 

 dentally such particulars of practice as might tend to illustrate the 

 subject, the details of the various processes of moulding, coring, melt- 

 ing, chasing, Ac., ic., are omitted, as belonging more properly to 

 founding and casting. [FouxDrao.] 



No particular reference has been made to the bronze weapons and 

 ornaments of the ancient northern nations, as they could not properly 

 be regarded as works of Fine Art, and they will be spoken of elsewhere. 

 Here it will be sufficient to mention, that in the barrows and other 

 sepulchral places of all, or nearly all, the northern races, bronze articles 

 are found in great numbers, and of a kind to show considerable skill in 

 the artificers. Host museums of antiquities contain numerous speci- 

 mens; and by northern antiquaries the presence of bronze articles is 

 regarded as a mark by which to assign the age of the person buried in 

 the tomb, the " brunze period" being one of their great divisions of 

 " primeval antiquity." 



The composition of different kinds of bronze will be found in the 

 preceding article. 



BRONZING ; BRONZE POWDER. Much ingenuity U displayed 

 in imitating the colour of ancient bronzes both the greenish and the 

 rich golden tints. Metals, wood, and plaster, are all subject to surface- 

 picii'iuste having this object in view. 



Captain Pidding states that the Chinese exercise the art of bronzing 

 in a very superior manner. After having nibbed the vase or other 

 ornament with coal-ashes and vinegar, they dry it in the nun, and then 

 coat it with a composition, of which the following are the ingredients : 

 two parts of verdigris, two of cinnabar, two of sal-ammoniac, two of 

 the beak and liver of duck, and five of pounded alum : moistened to 

 the consistency of a paste. When the article is thus prepared, it is 

 passed through the fire, and washed when cold ; again it is coated with 

 the composition, again fired, and again washed ; and so on for several 

 times in succession. 



Beequerel introduced to the notice of the Academic des Sciences, 

 several years ago, a method of bronzing, in which a thin layer of bronze 

 is applied to the surface of any article of iron, steel, lead, zinc, tin, or 

 other metal It U effected by precipitation from a solution, through 

 the agency of a galvanic battery, in the usual manner of electro-metal- 

 lurgy ; but the difficulty to be surmounted consists in the discovery of 



proper solution. The solution described by Beequerel consists of car- 

 bonate of potash, chloride of copper, sulphate of zinc, and nitrate of 

 ammonia : with a plate of brass or bronze as a positive electro-decom- 

 posing plate. 



A process of bronzing on paper is now frequently adopted for orna- 

 mental purposes. Thin plates of copper, or of copper alloy v< I with 

 some other metal, are beaten out into thin leaves, and these leaves are 

 ground or worked to powder. A pattern is printed on the surface of 

 paper with an adhesive and rapidly-drying varniah ; and just before 

 this varnish is dry, the bronze powder is rubbed on with a pi.-. 

 cotton, whereby a metallic lustre is produced, varying in it* tint from 

 a bright gold to a deep red colour, according to the metallic coiwtiln.ni- 

 of the bronxe powder. Sheets of paper, thus bronzed after having been 

 glased and printed in various colours, now form highly adorned c. < 

 for albums and many other kinds of books. In some of the recent novelties 

 in colour- printing, this mode of bronzing is adopted as an adjunct. 



BROWNING a process applied to gun-barrels. Various liquid* 

 are used for this purpose, comprising two or more iugrudieiitri from a 

 long Usf including aquafortis, spirit* of nitre, blue vitriol, muriate of 

 iron, butter of antimony, sweet oil, tc. The gun-barrel being well 

 polished, and the oil removed by means of whiting, the browning solu- 

 tion is laid on, allowed to remain several hours, and then rubbed ; 

 these alternate pioeinse* are repeated two or more times. The barrel 

 is afterwards cleansed with alkaline water, and polished. The natural 

 colour of the wood-work, and the artificial tint imparted to the barrel, 

 probably originated the designation of " Brown Bess," applied to the 

 army musket. 



I'dtnWXlSTS. (Hiu.wv KOBBKT; in Biou. l)iv.] 



HIUTIA I . called also " Voniiciiia." Medical 



Utet o/ The alkaloid above described exists in several species of 

 tryfknot, as well as in the bark of the false angostura ; and as it is 

 admitted on all hands that this bark is not obtained from any species 

 of Imicia, it ha* been proposed to change the name to Caniranua 

 (derived from Caniram, and the name under which the strychnoa mix 

 vomica is described in Rheede, ' Hort. Malaboric.,' v..l. i. p. 67). The 

 names are quite unobjectionable, as it exists in the strychnos mix 

 vomica along with strychnia ; but it is far from certain that the false 

 angostura is the bark either of the strychnos nux vomica or of the 

 strychnos oolubrina, as conjectured by V irey. [U AI.U-KA.] It is most 

 probably obtained from some uudescribetl South American species of 

 tan bait 



Caniramin acts on the human system as a poison, and in pre- 

 cisely the same manner as strychnia, but more gently, being much 

 less powerful. Hence it has been proposed to be substituted for it. 

 The same precautions must be observed in its use, and the same 

 coutra-iudications attended to. The cases in which it U most likely to 

 prove useful are paralysis from lead, diarrhoea from atony of the 

 intestines, and perhaps cholera asphyxia or Indian cholera. It i- 

 iinportant to bear in mind that the anhydrous state of the salt is 

 one-fifth more powerful than the crystallised. In case of poisoning, 

 emetics may be given, and al.-o tincture of bromine or iodine. 

 [STRYCHNOS.] 



BRUCINE. [Nux VOMICA, ALKALOIDS or.] 



BRUNOLIC ACID. This acid, the composition of whieh h.-is not 

 yet been determined, was found by Runge amongst the tarry products 

 of the destructive distillation of coal. It is brown, vitreous, and easily 

 reduced to powder. 



KKI'XSWICK (JKKKX. [GREEN.] 



BRUSH; BRUSH -MAK1XC. The ehief distinction in brushes is 

 that between what may be called timpic brushes, which consist of a 

 single bundle or tuft of hair; and cvmpoumt brushes, consisting of 

 several small tufts, separately inserted in a handle. Of simple brushes, 

 an illustration is afforded by the camels' hair pencil, the manufacture 

 of which is described under PENCIL. These hair pencils are made of 

 every variety of size, from the smallest pigeon or crow quill to the 

 largest quills of the goose, turkey, or swan ; and as even the largest 

 quills are not large enough for some kinds of brush or pencil, while in 

 other cases quills are not sufficiently strong and durable, tin tubes are 

 occasionally substituted for them, the handle or pencil -stick Wing then 

 iirmly fixed in the tube. Even the smallest kinds of pencil made of 

 bristles, or of the harder kinds of hair, for oil-painting, arc usually 

 mounted with tin, and are known by the general name of /W.<. I 

 some purposes, tin mounted tools are made flat instead of round ; the 

 hairs being arranged in a flat, or chisel-like, instead of a cylindrir.il 

 form. The larger kind of bri re not inserted in tubes, but 



are bound round very tightly and tied to the end of a wooden t 

 handle, which U cut into a forked shape, so as to have a projecting fin 

 on each aide of the bundle of hairs. 



Other brushes have the handle inserted in the tuft. Among these 

 are the large painting and dusting brushes used by house-pain tei 

 bristles of which are first tied or wrapped round, with the smal 

 of the conical wooden handle in their centre. The brush is tin n 

 upon a block of iron iwrforuted with holes to receive the handU . with 

 the points of the bristles uppermost ; and the conical handle i.s <h ivi n 

 in with considerable force, until the greater part of its len^i 

 passed through the brush to form the handle, While the thirki r end 

 remains in the middle of the tied portion as a sort of core. Ex. 

 in the peculiar mode of tightening the brush by the insertion of the 

 handle, carpet-brooms and birch-brooms resemble, on a larger scale, 

 this kind of brush. 



Intermediate between the simple and compound brushes are white- 

 wash and distemper brushes, which consist of two or more simple 

 brushes placed side by side, and secured separately upon the edge of a 

 flat hand I.-. 



Of compound brushes, which consist of numerous tufts or p. > 

 bristles or fibres, technically called knott, inserted separately iu holes, 

 the holes are bored in the stock, or back, by the aid i 

 I.or.i. The mode of fixing the knots in ' nui-work ' or 'set-work,' 

 is as follows : The brushmaker arranges evenly a sufficient quant 

 bristles to form a knot which will just enter one of the hole.- in the 

 stock, (irasping these firmly, ho dips the even end into a pan of melted 

 pitch and tallow, then scrapes off the superfluous pitch, and afterwards 

 takesa piece of strong thread called a thrum, and quickly binds it round 

 the bristles. The end of the knot is then again dip|>od in the pitch. 



i-erted in it* pro|>cr hole in the stock with a ]. 



twi.-iiii^' motion, which, coupled with the almost instantaneous setting 

 of the i is it very firm and secure. In this way are manu- 



factured long-brooms, bannister-brushes, hearth-brushes, and many 

 other kinds of house-broom, and also many of the lighter kind of 

 brushes, such as the dusting-brushes used for pictures and furniture. 



In most of the l.nishes hitherto described, the bristles are used of 



their full length, or .-ire \< r\ little < -ut ; but in such brushes an are used 



for scrubbing or hard rubbing, the tufts are made short and cut at 



ml* to a square even surface, and the root ends of the bristles 



brought to the surface as much as possible. Clothes-brushes, and some 



