CHAP. IV.
Of japanning.
Sect. I. Of japanning in general*
BY japanning is to be here underftood the art of covering bodies by grounds of opake colours in varnifh i which niay be either afterwards decorated by paintings or gilding, or left in a plain ftate. This is not at prefent praCtifed lb frequently on chairs, tables, and other furniture of houles, except tea waiters, as formerly : but the introduction of it for ornamenting coaches, fnuff-boxes, and Ikreens, In which there is a rivallhip betwixt ourfelves and the French, renders the cultivation and propagation of this art of great importance to commerce. I fhall therefore be more explicit in Ihewing the methods both now and formerly in ulc ; with the application of each to the lèverai purpofes to which they are belt adapted ; and point out at the fame time lèverai very material improvements, that are at prefent enjoyed only by particular perfons j or not at all hitherto brought into practice.
The fubftances which admit of being japanned are almoft every kind that are dry and rigid, or not too flexible : as wood, metals, leather, and paper prepared.
Wood and metals do not require any other preparation, but to have their furfaces perfectly even and clean : but leather Ihould be fecurèly ftrained either on frames, or on boards ; as its bending or forming folds would otherwife crack and force off the coats of varnilh ; and paper Ihould be treated in the fame manner ; and have a previous ftrong coat of fomè kind of fize; but it is rarely made the fubjeCt of japanning till it is converted into papier macbe, or wrought bv other means, into fuch form that its original ftatp, particularly with refpeCt to flexibility, is loft.
One principal variation in the manner of japanning is, the ufing or omitting any priming or undercoat on the work to be japanned. In the plder practice, fuch priming was always ufed: and is at prelent retained in the French manner of japanning coaches and fnuff-boxes the papier macbe: but in the Birmingham manufacture here, it has been always rc- jedted. The advantage of uling luch priming pr undercoat is, that it makes a faving in the quantity of vamilh ufed ; becaufe the matter of which the priming is compofed fills up the inequalities of the body to be vamilhed: and makes it eafy, by means of rubbing and water- polilhing, to gain an even furface for the varT nilh: and this was therefore luch a convenience in the cafe of wood, as the giving a hardnefs and firmnefs to the ground was alio in the cafe of leather, that it became an eftablilhed method $ and is therefore retained even in the inftance of fhe papier macht, by the French who applied the received method of japanning to that kind of work on its introduction. There is neverthe- lefs this inconvenience always attending the ufe of an undercoat of fize, that the japan coats, of varpilh and colour will be conftantly liable to bp craked and peeled olf, by any vicr fence, apd will not endure near lb long as the bodies japanned in the fame manner, but with- put any fuch priming: as may be eafily ob- jcrved in comparing the wear of the Paris and Birmingham fnuff-boxes; which latter, when good of their kind, never peel pr crack, or fuffer any damage, unlefs by great violence, and fuch a continued rubbing, as waftes away the fiib- fiance of the vamifh: while the japan coats of the Parifian crack and fly off in flakes whenever any knock or fall, particularly near the edges, expofes them to be injured. But the Birmingham manufacturers, who originally praCtifed the japanning only on metals, to which the reafon above given for the ufe of priming <did not extend, and who took up this art of themfelyes as an invention, of pourfe omitted at firft the ufe of any fuch undercoat; and not finding it more neceflary in the inftance of papier mache, then on metals, continue frill to rejedt it. On which account the boxes of their manufacture are, with regard to the wear, greatly better than the French.
The laying on the colours in gum water, in- ftead of yarnifhj, is alfo another variation from the method of japanning formerly praCtifed: but the much greater frrength of the work, where they are laid on in varnifh or oil, has occafloned ' this way to be exploded with the greateft rea- fon in all regular manufactures: however, they who may praCijfe japanning on cabinets, or other fuch pieces, as are not expofed to much wear and violence, for their amufement only, and confequently may not find it worth their while to encumber themfelves with the preparations tieceflary for the other methods, may paint With water colours on an undercoat laid on the wood, or other fubftance of which the piece to be japanned is formed; and then finifh with the proper coats of varnifh according to the methods below taught : and if the colours are tempered with the ftrongeft illnglafs fize and hony inftcad of gum water, and laid on very flat and even, the work will not be much inferior in appearance to that done by the other method ; and will laft as long as the old japan.
It is praétifed likewife, in imitation of what is fometimes done in the Indian work, to paint with water colours on grounds of gold ; in which cafe the ifinglafs fize, with fugar candy or hony, as above directed, is the beft vehicle.