C 42 ] 



and at between 500 and 600 takes fire, if in contact 

 with the air, and burns with a pale blue flame. In this 

 process it dissolves in the oxygene of the air, and pro- 

 duces a peculiar acid elastic fluid. The number re- 

 presenting it is 30. 



7. Phosphorus is a solid of a pale red colour, of 

 specific gravity 1770. It fuses at 90, and boils at 

 550. It is luminous in the air at common tempera- 

 tures, and burns with great violence at 1 50, so that 

 it must be handled with great caution. The number 

 representing it is 2O. It is procured by digesting 

 together bone ashes and oil of vitriol, and strongly 

 heating the fluid substance so produced with powdered 

 charcoal. 



8. Boron is a solid of a dark olive colour, infu- 

 sible at any known temperature. It is a substance 

 very lately discovered, and procured from boracic 

 acid. It burns with brilliant sparks, when heated in 

 oxygene, but not in chlorine. Its specific gravity, 

 and the number representing it, are not yet accurately 

 known. 



9. Platinum is one of the noble metals, of rather 

 a duller white than silver, and the heaviest body in 

 nature; its specific gravity being 21 50O. It is not 

 acted upon by any acid menstrua except such as con- 

 tain chlorine : It requires an intense degree of heat 

 for its fusion. 



10. The properties of gold are well known. Its 

 specific gravity is 19277. It bears the same relation 

 to acid menstrua as platinum : it is one of the char- 

 acteristics of both these bodies, that they are very dif- 

 cultly acted upon by sulphur. 



