198 



CHINA-WARE. 



covered ; be then places it on a board, on the points of 

 n.iils, and the unappropriated fluid drains oil", aud when 

 Ury it is placed in saggers (or glaze baking. 



The dipped vessels, when moderately dry, are placed 

 within saggers, and by stilts, triangles, rings, pegs, and 

 cockspurs, kept asunder, to prevent their adherence when 

 the gUze flows, and to allow all the material* of giaxe and 

 body to be properly annealed. The temperature is a white 

 heat of all within the oven ; and when the trials indicate 

 complete vitresceucu of the glaze, the fires are quickly 

 drawn, and the whole is left to cool, ready for the ware- 

 house. 



Ornamenting of glazed ware. This includes black print- 

 ing, lusterf/ig, ind enamelling. 



alack printing is the term for applying impressions to 

 glazed reisels, whether the colours be black, red, or gold. 

 The copper-plates are engraved in a style differing from 

 those employed in blue printing; and the colours are dif- 

 ferent in components and preparation. The following are 

 the component* of the colours : 



Black. 1. Copper calx, 20 ; flux, (t) 80. 



*. Copper calx 25 ; flux, () 75. 



3. Calcined borax, 4ii ; calcined umber, 35 ; blue calx, 0. 



4. Do. do. 25; do. 75, for gilded ware. 

 The green, purple, and pink, are the enamel colours 



fluxed a little more, with flux, (t) Instead of using paper 

 for taking off impressions, the black printer employs glue 

 bats, prepared in this manner: A definite quantity of 

 good glue is soaked well gome hours in water ; it is next 

 put into a large jug, and by the heat of boiling water eva- 

 porated during four hours ; afterwards it is poured out on 

 large well- glazed flat dishes, to the thickness of one-eighth 

 of an inch, and left to cool. The glue is next cut into 

 pieces, technically called papers, corresponding in size to 

 the plates. The printer rubs his colour, in the state of an 

 impalpable powder, well in a saucer, with a lock of carded 

 cotton, well dried. He, with rosin, fixes his plate to a wood 

 prism, as a handle, then rubs into the engraving his oil, 

 (a mixture of cold-drawn linseed oil, and oil of turpentine, 

 or Barbadoes tar,) and, with much pressure, the glue paper 

 abstracts the oil out of the engraving, and being immediate, 

 ly laid carefully on the ware, previously wiped very clean, 

 the oil, by a gentle pressure, adheres ; he next with a 

 pouge cleans the paper, and leaves it to dry, while he 

 applies the powdered colour, by the cotton to the oiled de- 

 sign. With a series of papers he proceeds successively till 

 his complement of ware is finished ; and afterwards, com- 

 menciug with the vessels first printed, with silk rags he 

 cleans otf all superfluous colour from the design, and wipes 

 all the other parts clean from whatever might be likely to 

 adhere to the glaze while being baked in the muffle. 



Lustred tvare. The body is usually formed of common 

 brick clay, 60, and blue clay and black marl, 20 each, 

 blunged well, and properly lawned ; fired biscuit, and then 

 covered with the brown glaze, No. 3. 



The components for the lustres are thus combined : 



Gold. In Intro-muriatic acid, sufficient, dissolve, 

 Gold, 120 ; grain tin, 5 : mix with (by heat) 

 Balsam of sulphur, 60 ; spirits of turpentine, 40. 

 Drop the acid solution in while stirring the medium ; and 

 when well mixed, use with best turpentine only. 1 ounce 

 of gold makes 32 of lustre. 



Persian gold lustre. In fat oil on a tile, placed on a 

 hot stove, mix dry oxide of gold, ami when eliquation com- 

 mences, stir with palette knife, and add more oil till 25 be 

 used, and the colour resemble that of balsam of sulphur; 

 then diminish the temperature, and gradually add turpen- 

 tine, 75. 



Silver, or Steel Lustre, In muriatic acid, concentrated, 

 dissolve platinum till the acid be saturated. Then at 112* 

 Fahrenheit, to 25 of solution, add very carefully, and in 

 small doses, 75 of spirits of tar. The chlorine will be 

 evolved by the heat, and the chloride of platinum will 

 remain in the tar. The metallic composition is applied to 

 the ware by broad hair pencils ; and this last, baked in a 

 muffle, at enamelling heat, is steel lustre. Then in water 

 mix the oxide of platinum, (obtained by sal ammoniac 

 precipitating it from the acid solution,) and cover the steel 

 lustre ; again bake, and it will be silver lustre. If the 

 glaze be opaque, not brown, this latter will at once give 

 filter lustre. The gold lustre is used with turpentine 

 similarly ; and, recently, a new kind has been in the mar- 

 ket, of whose components we have not yet been able to 

 obtain determinate knowledge. 



The Muffle for baking ornamented glazed ware, is of a 

 size in proportion to the quantity usually in demand ; and 

 is constructed so as to prevent any vapours entering from 

 the fuel. Considerable judgment is requisite for properly 

 placing the different articles in this kiln ; but this is the 

 general principle : the lustres are least liable to injury by 

 baking; the rose colour, purple, cornelian red, pomona 

 green, and gilt for burnishing, have a central situation ; 

 around them are placed articles in colours less affected by 

 fixing oxygen. A layer is placed, with props fixed in dif- 

 ferent parts ; on these, bats of half an inch thickness and 

 20 to 30, by 12 to 16 surface, are laid all the length ; and 

 v.are placed thereon: repeating this arrangement till the 



whole is filled, and then the aperture is closed ami Ibo 

 baking commenced, and continued until the colours appeal 

 properly combined with the glaze; which the fireman as- 

 certains by inserting a bit of deal stick in the kiln, and its 

 white flame renders obvious all the colours on the ware. 



i.im II linn f j'li'jivi IIMIIII n/ in; UUI iltAIHU Wllll ttgaie, iUHl 



blood-stone, and then carried into the warehouse to be 

 wrapped in tissue paper for the market. In every process 



inuruia- 



tion, in equal proportion must there exist self condemna- 

 tion for wilfully misleading those who are seeking in- 

 formation. Ignorance is not a sin. Where I have not 

 understood the process, 1 have avowed its being unknown 

 to me. 



Enamelling of China and Earthenware. This art of 

 executing designs on the glazed sun ace of ware, with 

 colours so vitriiiable as readily to acquire lustre at a mo- 

 derate heat, or cherry-red heat, without complete fusion, 

 has only been practised about eighty years in potteries. 

 The colours, or enamels, are formed of a transparent and 

 fusible glass, which has metallic oxides chemically combin- 

 ed to impart the necessary tint. The oxide of gold is used 

 for purple and rose colours, also for a beautiful lustre ; that 

 of silver for yellow ; cobalt for blue ; copper for greens and 

 blacks ; antimony for yellow ; umber for black and brown ; 

 platinum for steel and silver lustre ; manganese for violet; 

 chrome for cornelian red, and pomona green ; and iron, in 

 different states for red, brown, and black. A little more 

 detail may not be improper in reference to some of the 

 preparations. 



equivalent trf muriate of tin, and continue stirring the 

 fluid half an hour ; then add boiling water, till quite in- 

 sipid ; leave the fluid twenty-four hours to rest, and then 

 with a siphon draw off the water, without disturbing the 

 precipitate. Into this water stir a saturated solution of mu- 

 riate of ammonia, that any oxides left may be precipitated ; 

 or hydro-sulphuret of ammonia. For use, the precipitate 

 is ground with 30 to 45 parts of flux ; of red lead, 7 ; borax. 



10 ; flint, 2. 



The Rose Colour. In water just below boiling, (190) 90 

 parts, mix 10 parts of saturated solution of gold ; then pre- 

 cipitate by plus of muriate of ammonia, of a yellow tint; 

 let the precipitant be added at different times for twenty- 

 four hours, and then rest twelve hours for all to go down, 

 with a siphon draw off the water, as in purple ; add boiling 

 water till insipid. Dry the precipitate on a plaster bat ; 

 but, being fulminative, must be kept quite cold, and not be 

 triturated until mixed with flux. The flux is, a fritt of 

 flint, 38; borax, 32; red lead, 28; glass, 2. Grind well 

 with silver, 1 ; to precipitate, 9 ; and flux 30 to 40 parts. 



Red. The peroxide of iron, by calcining copperas over 

 a fire, and frequent washing. For use, grind calx, 25, and 

 75 of flux ; a fritt, glass, 66 ; red lead, 25 ; borax, 9. 



Brown. Dark. Brown oxide of iron, 30 ; flux, 70 ; 

 fritt, glass, 86; calx, borax, 14. Light. Calx nmbcr, 14; 

 yellow calx, 14 ; peroxide of iron, 6 ; flux (red), 66. 



Purple Distance. Purple, 12 ; manganese, 18 ; flux, 70. 



Green. Blue. Sulphate of copper calcined, 20 ; flux, 80 

 Fritt. Borax, 16 ; white enamel, 16 , red lead, 50 ; flint, 18. 



Green. Grass. Blue green, 77 ; enamel yellow, 23. 

 Yellow. do. 66; do. 34. 



Yellow. Naples yellow, 33; flux, 67. See Green. 



Orange. da 25 ; biscuit orange, 25 ; flux, 50. 



After being properly dried, and ground at a mill, each 

 colour is ground on a very hard stone, or glass plate , 

 and afterwards used with spirits of turpentine, and hair 

 pencils. 



That the enamels may answer, the glaze must corre- 

 spond therewith, else the dilution will cause a design, ap- 

 parently finished, to come out of the muffle a mere sketch ; 

 while the flux must bake at the same heat as the glaze, to 

 preserve the brilliancy of the metallic base, and neithei 

 craze, nor scale off. 



The repetitions of the artist's efforts are indispensable to 

 the finished appearance of many designs; which only by 

 several bakings can receive that softness of colouring, and 

 unfading brilliancy, which are essential to their elegance 

 and full effect. The softness of the glaze during baking 

 allows the metallic base to be imbedded therein, and when 

 cold to be smooth and brilliant. The alkaline glazes, on 

 this account, are only excelled by that of felspar, which in 

 baking, receives the colours, and improves their tints. 



Gilding of China and Earthenware. This manipulation, 

 (in which, as well as the preceding, there is opportunity 

 for displaying the greatest taste,) empioys hair pencils and 



011 of turpentine, with a preparation of the proto-muriate 

 of gold, (obtained by dropping muriate of gold into a solu- 



