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all wild rubbers—I do not say fine hard Para, but all wild 
rubbers. ; 
The next point I want to speak of is the use of sodium 
bisulphite. The use of this material is being very severely 
criticized in various quarters, and as I was largely responsible 
for the introduction of sodium bisulphite, perhaps I may be 
allowed to say a few words in defence of this much maligned 
substance. Now in the first instance sodium bisulphite was 
used in order to produce a rubber of paler and more even 
colour. I want to emphasize the words ‘‘ more even,’”’ because 
it was not merely a question of paler, but of more even colour. 
We are informed by Mr. Williams this morning, and shall no 
doubt be told by many other manufacturers, that the question 
of the colour of rubber is of no importance—that a dark 
rubber, as he said (and I agree), may be frequently much 
better than a pale rubber, and that consequently it is a very 
serious mistake for plantations to use chemicals, even, mild 
chemicals, for the preparation of rubber pale in colour, when 
such pale colour is not in demand. Now the answer to that 
is very simple. For quite a long while, and even to some 
small extent to-day, pale, even-coloured rubbers fetched a 
better price (it may have been only a halfpenny or a farthing 
per lb., but still a better price) than dark-coloured rubbers, and 
naturally enough the planters take means to produce rubbers 
which fetch a better price in the market. 
Now I want to refer specifically to some experiments which 
Mr. Williams quoted in reference to the use of sodium 
bisulphite. Firstly, he stated that he had tried mixing small 
quantities of sodium bisulphite with rubber, and vulcanizing it 
with such admixture, and that he had obtained results which 
tended to show that the bisulphite was extremely harmful. Mr. 
Williams stated, I think, that the maximum amount of sodium 
bisulphite found in plantation rubber was o's per cent. I 
hardly think he meant that, because I have frequently examined 
bisulphite-treated rubbers for bisulphite, and have not detected 
any, and hardly expected to. The bisulphite can only be 
detected in the form of sulphate, and some allowance must 
naturally be made for sulphate being present even in untreated 
latex. I think, therefore, that possibly Mr. Williams’s figures 
require a little adjustment. Taking the result of these experi- 
ments, I do not think it is a fair method—and when I say I do 
not think it a fair method, I do not suggest that any other 
course was open to Mr. Williams, but I do not think it a fair 
method to mix sodium bisulphite with rubber, and then to test 
it against rubber untreated. It is very different mixing a salt like 
that with crude rubber, to putting a dose of the salt into the 
latex in solution. In this connection I want to revert specially 
