JONES, ON JAPANNING AND VARNISHING. 35 



filtration ; this, however, does not interfere with the goodness of 

 the varnish, and may, probably, add to its toughness. Should the 

 solution prove too thick, more alcohol may be added ; this is best 

 done in small quantities, as the varnish is used. Where hardness 

 is not a point of importance, a small lump of common rosin is add- 

 ed to the shell-lac, as this substance increases the brilliancy of most 

 of the varnishes ; it ought, however, to be used with a sparing hand, 

 as it renders every species brittle. 



Shell-lac is of a yellowish brown color, and will not, therefore, 

 answer for those articles which would be injured by this tint ; it is 

 otherwise the best of the common spirit varnishes, whilst it at the 

 same time, is the cheapest. It answers well upon mahogany, and 

 upon most colored articles ; but when used upon those which are 

 black, it must be made of that color, in a way to be hereafter de- 

 scribed, or it will give an evident shade of brown. 



When wood, or other porous materials, are to be varnished, they 

 ought to be coated with some substance which will cause it to bear 

 out ; the pores may thus be completely filled, and much time and 

 varnish saved. For mahogany, and some other woods, boiled lin- 

 seed oil may be used, particularly if il is desirable to heighten the 

 color. Thin size, made from common glue, that from isinglass, the 

 glare of eggs, gum-water, or gum tragacanth, are occasionally em- 

 ployed ; the object in view, being to prevent the absorption of the 

 varnish by a coating of some substance not soluble in alcohol. 

 When linseed oil is used, it ought to be rubbed on sparingly, then 

 wiped carefully off, and a day or two should be allowed for it to 

 harden, before the varnish is put on. 



For ordinary work, the varnishing brush may be a sash-tool of a 

 suitable size, as the varnish, if not too thick, will flow and spread 

 itself evenly, although the hairs of the brush may not be fine. — 

 When the varnish is used thin, and the articles to be varnished are 

 of the finer kind, or the surface great, the flat, camel's hair brushes, 

 are to be preferred. In general, three or four coats will be found 

 necessary, and when wood is very porous, or the varnish is to be 

 rubbed down, and polished, double the number may be required. 

 In dry weather, the spirit evaporates so rapidly, that the coats may 

 follow each other, at an interval of a few minutes only ; but great 

 care should be taken that the last be perfectly dry, before another 

 is laid on. It frequently happens, that the varnish assumes an 

 opaque white appearance, as it is laid on, losing all its brilliancy. 

 This is occasioned by the moisture in the atmosphere, and indicates 

 that a close room, and a fire, are necessary ; and without these it 

 will be useless to persevere. The transparency will, however, be 

 restored by the next coat of varnish, if laid on in a place that is 

 warm and dry. This frequently occurs, when, judging by appear- 

 ance, we should think the day most suitable for varnishing. 



It will be perceived, that many of the preceding remarks apply 

 to spirit varnishes, in general, as they all possess certain propnties 

 in common, and require, therefore, a similar mode of ticatment. 

 The mode of polishing, and some other particulars, which will be 



