168 EXTRACTS FROM FORBION JOURNALS. 



traordinary group of corallines, which have hence frequently been considered 

 as animals. The formation of silex occurs pre-eminently in Indian grasses, 

 bamboos, and even trees. Dr. Moore observed that within the Circars, as 

 far as Nagpore, consequently within the district watered by the Kistna and 

 Godavery, a species of Jungle grass, with which Dr. Roxburgh was unac- 

 quainted, grows in immense quantities upon the mountain heights, in the 

 knots of which a secretion of perfect silex takes place. The Calamus rotang, 

 Equisetum hiemale, and certain species of bamboo, also produce these secre- 

 tions of silex, which are better known by the name of Tabaschir, or vegeta- 

 ble opal. The bamboo in which this Tabaschir is secreted, Langford Ken- 

 nedy observed in great quantities in the wilds of the mountain around Ram- 

 guhr, thirty geographical miles to the west of Calcutta, consequently in the 

 vicinity of the sources of the rivers Brahmani and Mahanadi, along which it 

 may also be distributed. This species of Bambas is called at Ramguhr Kut- 

 binbanse — that is, prickly wild bamboo — and the siliceous secretion Banselo- 

 chum. It is not every plant which produces this secretion ; those who seek 

 it shake the stems, and detect it by its rattling within those plants which 

 exceed in their stem two inches and a half in diameter. In the east- 

 ern islands it is found in much larger stems, but it is then of a dirty yel- 

 low colour. There are two different kinds; the one nearly white, but 

 opaque, and the other resembling opal, but without any polish. The physi- 

 cians of the Hindoos use it as a medicine, and it costs from eight to ten shil- 

 lings the pound. Dr. Turnbull Christie observes that this Tabaschir is not 

 found in all parts of India, nor in all the species of the same genus of bamboo, 

 nor even in all the bamboos of the same locality. The secretion of this silex, 

 therefore, may be referred to certain local and individual vegetable peculia- 

 rities which stand in a yet unknown connexion with its range of occurrence, 

 like that of the diamond. As long as the bamboo is green the Tabaschir is 

 moist and transparent, analogous to chalcedony in basalt, which becomes 

 opaque by exposure to the air before it can be removed from the fissure. 

 The Tabaschir possesses a similar property to Chalcedony, for by chemical 

 analysis it produces silex. The bamboos are not the only plants which pro- 

 duce silex. The iron-wood, Calumidiri, and others which have been brought 

 from the forests of Ava, are so filled with condensed carbon that they ac- 

 quire almost the hardness of diamonds, and rather resemble petrifactions 

 than succulent vegetables. It therefore becomes probable that many of the 

 so called petrified species of wood have killed themselves by a superabundant 

 secretion of the siliceous matter ; whence we may comprehend their wide 

 disjjersion in both the deserts of Africa and Asia. Similar concretions of si- 

 lex have frequently been found in abundance in the hard teak wood, the 

 analysis of which, according to Wollaston, gave silex which appeared to 

 come most closely to the diamond carbon, and seemed to support Jameson's 

 interesting hypothesis of the possibility of a vegetable origin of this jewel, 

 but which, indeed, still requires many experiments and observations to con- 

 firm Ritter Erdkundey vi., 365. 



MISCELLANEOUS. 



Van Mander at Florence. — Two thirds of the fifteenth century — at 

 which period commenced in Belgium the revival of painting by the invention 



