40 CllYPTOGAMIA. 



EQUISETUM HYEMALE. Rough horse-tail. 

 Of this plant there are seven species ; it is a native ot 

 boggy woods and thickets in several parts of the king- 

 dom. The root is perennial., and the stem is erect, 

 which lasts throughout the winter ; hence the specific 

 name hyemale: the fructification appears in summer. 

 This plant has long been imported in a dried state from 

 Holland, by the name of Dutch rush, to polish cabi- 

 net work, ivory, and brass. The cuticle is extremely 

 rough and hard, and is found to contain a large por- 

 tion of flinty earth. 



In many parts of the East there has long been a 

 medicine in high repute, called Tabasheer, obtained 

 from a substance found in the hollow stem of the 

 Bamboo cane, some of which was brought to Eng- 

 land about twenty years ago. It underwent a chemical 

 investigation, and proved to be an earthy substance, 

 principally of a flinty nature ; this substance is also 

 sometimes found in the Bamboo growing in England. 

 In the hot-house of Dr. Pitcaim at Islington, subse- 

 quent to this time, there was found in one of the joints 

 of a Bamboo which grew there, on cutting it, a solid 

 pebble withinside about the size of a pea. 



The pebble was of an irregular rounded form, of a 

 dark brown or black colour. Internally it was red- 

 dish brown, of a close dull texture, much like some 

 martial siliceous stones. In one corner there were 

 shining particles which appeared to be crystals, but 

 too minute to be distinguished, even with a microscope. 

 This substance was so hard as to cut glass. 



