590 GRAMINE^. 



James Louis Macie to make an analysis, wliicli showed that it 

 consisted principally of silica. 



Fnrtlier information on Tabashirmay be obtained from Prof. 

 Fliickiger's papers above mentioned, and a paper by Dr. Brandis 

 in the Indian Forester^ March, Vol. XIII. 



V 



Description. — Tabashir consists of irregularly- shaped 

 fragments of an opaque white or bluish opalescent colour, the 

 larger pieces are about an inch in diameter, concavo-convex, and 

 have evidently derived their form from the joint of the bamboo 

 in which the deposit has collected. The raw article is blackened 

 and dirty, having apparently been obtained by burning the bam- 

 boos, or on account of the presence of insects ; to make it fit for 

 use it is calcined, when it becomes perfectly clean. 



Chemical composition. — Cavendish {Ebendciy 370) determined 

 the specific gravity of Tabashir to be 2*169 at 11'4°C. 



Humboldt remembered the analysis of Macie when he and 

 Bonpland discovered a similar substance at the volcano of 

 Pichincha, not far from Quito. He wrote from Mexico on the 

 22nd of April 1803 to Antonio Joseph Cavanilles, Director of 

 the Botanic Garden at Madrid {Annales du Museum, iv. (An. xii., 

 1804), 478)— *'Vous vous souvenez sans doute de cette 

 substance siliceuse, ressemblante a Topale que M. Macie 

 analysa en Angleterre. Nous Tavons decouverte a Touest du 

 volcan Pichincha, dans les bambous ou gros roseaux 

 appel^s Guadiias dans le royaume de Santa Fe. J'ai fait des 

 experiences chimiques sur le sue de cette grarainee colossale^ 

 avant que la substance siliceuse se fut deposee, et j'y ai 

 remarque des phenomenes tres-curieux ; il est susceptible d*une 

 putrefaction animale, et parait annoncer une certaine combin- 

 aison d'une terre simple avec Pazote/^ The Giiadtias are the 

 representatives of the Indian bamboos in South America and 

 closely related to them. The specimen of American Tabashir 

 which Humboldt sent to Paris was examined by Fourcroy 

 and Vanquelin (Ann. du Miis., vi. (1806). 382—385); they 



besides 70 per cent, of silicic 



and lime. It would be 



S 



perhap 



