394f Scientific Intelligence. — Botany. 



The age of the tree was about 80 years. There arc several 

 larger still standing at the same place, which are supposed to 

 be some of the largest and oldest in England. — W. C. T. 



17. On a New Vegetable Razor-Strap. — Having observed, 

 when at Buenos Ayres and Monte Video, previous to my re- 

 turn to Europe in 1828, that the barbers were in the practice of 

 giving a fine edge to their razors, by using instead of a razor- 

 strap a portion of the stem of a monocotyledonous plant, divid- 

 ed in the direction of its fibres, I made inquiry from whence 

 they obtained it, and was informed that it was procured from 

 Rio de Janeiro. Accordingly, on my subsequently visiting 

 that place, I took care to obtain a supply of it, and have not 

 only ever since used it myself as a razor-strap, but have induced 

 many of my friends to do so likewise, with the most satisfactory 

 results. From a belief at one time entertained, that the pre- 

 sence of minute particles of silica interspersed among the fibres 

 of this substance, might give rise to its peculiar property of 

 giving a fine edge and polish to cutting instruments, I was in- 

 duced to request of my friend Mr James F. Johnston to sub- 

 ject it to analysis, to ascertain whether it contained any silica ; 

 but, after a most careful investigation, he could not find it to 

 contain the least trace of any siliceous earth. It is evident, 

 therefore, that its useful properties as a razor-strap depend on 

 the mechanical management of the numerous longitudinal fibres 

 of which it principally consists, and which, being surrounded 

 on all sides by a quantity of light cellular substance, is rendered 

 somewhat elastic. This substance is of a dirty white colour, 

 with a specific gravity, according to Mr Johnston, of "09 in its 

 porous state, and about '3 after its being boiled in water to ex- 

 pel the air. To prepare it for use as a razor-strap, it is only re- 

 quisite to divide the portion of the stem to be used in a direc- 

 tion parallel to that of the fibres, and forming a flat surface, 

 which is rendered smooth. I have also understood that it is 

 likewise used as a substitute for cork to line boxes in which in- 

 sects are preserved, and some give to it a decided preference for 

 this purpose. I am likewise informed that it is sold for this 

 object at Guayaqi'il, on the Pacific coast, under the name of 

 Balsa Wood, Avhich name it has probably obtained from its 

 great buoyancy. At Rio de Janeiro, I was informed that it 



