Troup ; Cutch Trade in Burma. 
257 
One of the chief defects of catechu is the tendency of the prepared 
colour to undergo oxidation before it is used for printing, owing to the 
combined action of the air and the copper sulphate present in the colour. 
A finely divided precipitate is thus produced, rendering the colour gritty 
and unfit for use. Catechu printing colours which have not been suffi- 
ciently boiled, or do not contain sufficient acetic acid, are liable to deposit 
crystalline catechin, with the same result as above. The oxidising agents 
used for developing the colour are also liable to bring about tendering of 
the fibre, especially if chlorates are employed. These and other defects 
have led many printers to seek for satisfactory substitutes. Among those 
of recent introduction are Fast Brown J. A. and Fast Brown E. S. 
(A. Huillard), which are apparently prepared from natm'al dyestuffs, and 
have the same defects as catechu. Another substitute is catechu brown 
O. S. C. (O. Starcke and Co.) ; this yields smooth and stable printing 
colours, and the shade can be varied at will by the addition of colouring 
matters capable of being fixed with chromium acetate, this being the only 
substance necessary to be added to the thickened colour. 
“ Printing Brown P. M. B. (P. and M. Bohme) greatly resembles 
the colom’ just described, and yields shades which are fast to washing and 
to acids. — R. B. B.^^ 
(5) idulteration and faulty manufactv,re . — Enquiries have been ad- 
di’essed to many of the leading cutch importers and users, and their unani- 
mous opinion is that the quality of cutch manufactm'ed now-a-days is 
superior to what it was some years ago, when adulteration was freely 
practised on a large scale. There can be no doubt that this adulteration 
did a great deal of permanent harm to the cutch trade, which can never 
hope to regain what it has lost, as this adulteration was one of the primary 
causes which led dyers to forsake cutch for aniline substitutes. The chief 
fault to be found with the cutch now manufactiued is that some of it 
contains an undue amount of moisture. It has frequently been suggested 
that cutch, though it may be pure when it leaves the manufacturer's hands, 
is often subject to adulteration by the brokers throiigh whose hands it 
passes. To test the accm’acy of this statement, samples of cutch were 
obtained from cutch-boilers' camps and from the brokers' warehouses in 
Rangoon and subjected to chemical analysis. In each case the samples 
were taken haphazard from the stocks in hand. The results of the analysis 
are given in Appendix B. As the total number of samples received was 
