348 ART INDUSTRY AND RELATED OCCUPATIONS. 



and becomes of a jelly-like thickness, which when painted on wood 

 or other groundwork, dries very quickly. On the other hand, 

 besides heat, camphor or Shono is the only material for thinning 

 the lac known to the Japanese from earlier times and is the only 

 one still used. It is taken in its usual granulated and crystalline 

 condition, pulverized and mixed with the lac by the spatula and 

 thus made liquid. Camphor oil, although it answers the same 

 purpose very well, as my experiments with it in the presence of my 

 Japanese lacquerers proved, appears never to be used by them. 



Among the properties remaining to be noted in the material under 

 treatment are these ; that it turns to black on exposure to the light, 

 dries easily in a damp atmosphere in ordinary temperature, and 

 that its evaporation produces a kind of poison which is the cause 

 of the lac-disease. 



The drying of fresh lacquer-painting differs from that of our 

 resinous varnishes in that it is not promoted by artificial heat, but 

 is best accompHshed in a damp atmosphere, as free as possible 

 from dust, in the ordinary temperature, between io° and 25° C. or 

 at most 30° C. The direct rays of the sun are injurious, because 

 the heat is uneven, and the stronger it is the more it hinders drying. 

 The lacquerer fulfils the necessary conditions by choosing a dark 

 room (chest, closet or chamber) in the most quiet retired place, 

 and provides against the insufficient moisture of the atmosphere 

 by some artificial means. 



In a small shop, where a roomy chest with some boards inside 

 resting on cross-pieces suffices for the work, the boards, the inner 

 walls and the cover are all washed with cold water before the 

 freshly painted lacquer wares are placed in it to dry. In other 

 cases a large cupboard is treated the same way, for the same 

 purpose. If it is necessary to use an entire room, it is customary 

 to hang wet cloths on the walls, and to set vessels of water about 

 in order that the necessary moisture of the atmosphere may be 

 gained through evaporation. 



Father d'Incarville says on page 127 of his before-cited work : 

 " Ici a Peking, ou I'air est extremement sec, pour secher le vernis, 

 il faut necessairement I'exposer dans un endroit humide, entoure 

 de natte, que Ton arrosera d'eau fraiche ; autrement le vernis ne 

 secheroit pas ; si c'est une piece mise en place, qu'on ne puisse 

 detacher, ils sont obliges de I'entourer ainsi de linges mouillies."^ 



The lac-acid extracted by means of pure alcohol does not possess 

 this peculiarity of drying, as I learned in 1874, and as the numerous 

 experiments of Korschelt have shown later. It hardens only when 

 it is mixed with the albumen and water, as in lac. The mixture, 

 however, loses this property when heated over 60° C, i.e.y above the 

 temperature in which albumen coagulates. 



^ In this connection, his countryman Watin, in his book on the Art ot 

 Decorators, Gilders and Lacquerers, says, "This observation seems contrary 

 to all experience." 



