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juice collected is not considered of the correct quality for making sugar 
and is not used. Previous to suspending the bamboo pipe to collect 
the sap it is fumigated over a smoke fire and a small piece of lime is 
placed within, both operations being to prevent the saccharine juice from 
fermenting while being collected in the pipe. As the juice is collected 
it is boiled in a pan for about an hour and constantly stirred. It is 
then poured into small shallow moulds and allowed to harden and it is 
in this state that it is bought in the markets. 
Other useful articles manufactured from the Kabong palm are, 
rone from the fibre which covers the stem, walking sticks from the split 
stem and brushes from the stiller fibre and the young fruits are pre- 
served in sugar and sold as a sweetmeat. A very good sago is manu- 
factured from the medulla of the stem so it can be seen that there is 
scarcely a part of this useful palm that cannot be used for some 
purpose by the native. 
F T. W. Main, 
POISONS EXCRETED BY PLANT ROOTS. 
It has always been a popular idea that certain plants such as 
bananas and tapioca poison the ground they have grown on, but no 
important evidence to show this has till now been brought forward. 
We have just received an article entitled a note on a Toxic substance 
excreted by the roots of plants, by Mr. F. Fletcher, Deputy Director of 
Agriculture, Bombay Presidency. The article is published in the 
memoirs of the Department of Agriculture m India April 1908, II 
No. 3. The subject is of the utmost importance to all planters, and 
though this article is only a first glimpse of a new and most valuable 
line of research it contains in a few pages some most important facts 
and conclusions. The experiments were made by growing various 
plants viz., cotton, sorghum, cajanus, sesamum, wheat and gram in 
water and experimenting with the water in which the roots of the 
seedlings had been growing. 
Evidence was obtained first that the toxin excreted by the different 
plants was identical but varied in amount, gram and sesamum being 
the worst. “ It was at first thought that the toxic matter might be an 
albumose or similar substance. The solutions all gave negative results 
however. The fact that tannic acid precipitated and corrected the 
toxic material suggested the presence of an alkaloid. It is interesting 
to note that leaves containing tannic acid are systematically used as 
manure in the spice gardens aftd rice fields of Canara and that the 
cultivator’s opinion as to the manurial value of the leaves of any partic- 
ular variety of tree corresponds apparently to the amount of tannic 
acid contained in the leaf. ” 
In old pepper and gambier growing days in Singapore it used to be 
the custom here to mulch the pepper with the old gambier leaves after 
they had been boiled and though much of the tannic had been extracted, 
there was a good deal left in the roughly boiled leaves. 
“ That it is not the ash constituents of these leaves that produce 
the manurial effect is obvious from the fact that if the leaves be burnt 
and the ashes applied to pepper, the pepper vine is killed.” 
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