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transparency of the lac used when dried. The degree of lustre can well 

 be examined at the same time as that of transparency. Freshly coated 

 glass hardly shows any distinction between different kinds of lac applied. 

 Later, when the coatings are almost dry and assume a dark color, the 

 distinction is clearly shown. For example, lac rich in urushiol becomes 

 transparent and brown in color while one with a large admixture of 

 gummy and nitrogenous substances becomes opaque. 



The more urushiol lac contains, the more transparent and lustrous it 

 is, and the better is the quality, on the other hand, the more rich in 

 gummy and nitrogenous substances the lac is, the worse is the quality. 



VI. Qualities of Lac Compared 



1. Comparison of different Sorts of Lac. 



By comparing the results of analysis, the drying power, transparency 

 and lustre of the different sorts of lac produced in the Iwate Prefecture, 

 from trees having an average circumference of 63.6 cm we see that 

 " Prime lac " stands first in quality, " early lac " next, followed by " final 

 lac," " short lac " (urame) , " tail lac " (tome) and " branch lac " in order 

 of quality. As to the lac collected from trees, 21.2 cm in circumference, in 

 Kanagawa Prefecture " prime lac " took the lead while " early lac " was 

 surpassed by " final lac " and " short lac " in quality. In general, lac 

 obtained by the prime exhaustion method was slightly richer in urushiol 

 than the corresponding product obtained by the ordinary exhaustion 

 method but not much difference was observed so far as the content of 

 nitrogenous and gummy substances was concerned. As to quality, the lac 

 obtained by the prime exhaustion method is somewhat better. 



