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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 saecharine 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, 

 rope from the fibre which covers the stem, walking sticks from the split 

 stem and brushes from the stiff er 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. 



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. R Fletcher, Deputy Director of 

 Agriculture, Bombay Presidency. The article is published in the 

 memoirs of the Department of Agriculture in 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 and 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 beenboiled 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." 



