430 ON GRASS-TREE GUM, 



resin. It is occasionally called " black-boy gum," and in 

 English books now and then " acaroid resin " or " gum accroides." 

 It has also been called " Botany Bay resin." 



Collection and Commerce. 



" Grass-tree gum " is in small demand, the ordinary retail price 

 being from fourpence to sixpence a pound in Sydney, and the 

 wholesale price of course much less. As usually found in com- 

 merce, the resin of X. hastilis is in veiy small pieces (almost 

 powder), or else these small pieces are aggregated, forming a 

 friable mass. la this state it is more or less impure, being mixed 

 with soil and fragments of the bases of the leaves. X. arborea 

 resin is usually in larger masses. After a bush-fire (or even the 

 heat of the sun) has passed over grass-trees, the heat causes the 

 resin to run into more or less spherical masses, which are some- 

 times also darkened, either from destructive distillation, or possibly 

 by admixture with carbon particles. I have some pieces as 

 spherical as if turned in a lathe. These masses can be picked out 

 either from the interior of the charred stump, or from the ground 

 at the place where a grass-tree once grew. Such masses present 

 the resin in a very pure form, but collecting in this way would 

 entail too much labour to be profitable commercially. 



Following is a description of the method of obtaining grass-tree 

 "gum." 



The ai'ticles required are an axe, a flail, a coarse sieve, and a 

 sheet. The stems of the grass-trees are chopped down, broken up 

 into convenient pieces, and allowed to fall into the sheet. A stout 

 stick or flail completes the work of disintegration. The substance 

 is then passed through the sieve, the ligneous portions of the grass- 

 tree for the most part failing to pass through its meshes. A gentle 

 breeze is considered sufiicient to winnow what has passed through 

 the sieve, and render it ready for the market. But it often comes 

 to Sydney without having been subjected to any winnowing 

 process. 



An interesting (though now somewhat out of date) account of 

 grass-tree " gum," by Mr. P. L. Simmonds, will be found, Pharm,. 

 Journ. [2], viii., 78. It is, however, to be observed that the 

 collection of the resin now gives employment to very few persons. 



