Indian Forest Records. 
58 
[Voi,. VIII 
manual process has hit off by sheer accident the proportions of resin 
and wax which produce the best quality shellac known. So little 
research has, however, been carried out in this branch of the subject 
that no definite facts can be stated and the true explanation of the 
difference between hand-made and machine-made shellac may be 
found to be entirely different from that suggested above. 
The properties which appear to make shellac the valuable article 
it is, are its insolubility in water and ready solubility in other 
cheap solvents ; its comparative hardness among gums ; its immunity 
to change when exposed to the atmosphere ; its elasticity and power 
of adhesion to smooth wood and metal surfaces on which it can be 
spread in very thin layers; its flux or power to assume with great 
exactness the shape of a mould to which it is applied ; its power of 
electrical resistance. 
At present the requirements of the trade in a good shellac are, 
firstly, cleanness, freedom from dirt, insoluble matter and adulterants; 
and, secondly, paleness of colour. Low grade shellacs are dark 
orange and high grade shellacs run up to a very pale yellow. This 
prejudice in favour of pale colour can be of no real importance to 
many consumers, especially to the gramophone record manufacturers 
who take nearly half of the shellac manufactured. Unfortunately 
prejudice has so firmly fixed colour as the standard of the trade that 
even when a more practical standard is discovered it will be difficult 
to get it recognized. 
No complete analysis of shellac has ever been published, and the 
usual procedure of the chemist to whom 
Analysis. . _ ... 
samples are submitted for analysis is to 
apply certain tests from which definite facts can be deduced. The 
two most important tests are: — 
1. The determination of the percentage of insolubles in boiling 
alcohol. 
2. The determination of the percentage of rosin. Details of 
the methods employed will be found in Allen’s Commercial Organic 
Analysis, Volume IV (London, J. and A. Churchill). 
In the old days in India there used to be considerable local 
Methods of manufacture. prejudice against the manufacture of 
The manual process. shellac. There is still current a proverb 
“ Sau kasahi ek lahi “ One lac manufacturer is as bad as a hundred 
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