HYDROGEN AND CARBON. 59 



Hydrogen gas combines with several simple 

 bodies, constituting, with them, peculiar and dis- 

 tinct gases. 



Hydrogen and Carbon. 



Hydrogen gas unites to carbon, and forms, with 

 it, HydrO'Carhonate gas. Of this there are two 

 kinds, according to the quantity of carbon which 

 they contain. 



Light Hyd?^o-Carbo?iate. — This is frequently 

 seen rising from stagnant ponds, when stirred. It 

 may also be procured by passing the vapour of 

 water over red hot charcoal. It burns with a pale 

 blue flame. It is also called Light carbureted Hy- 

 drogen. It is contained very abundantly in 

 many coal mines, where it is disengaged from 

 fissures in the strata, often in great quantities; 

 which are called by the miners blowers. When it 

 has accumulated iu any part of the mine, it forms 

 an explosive compound, by its admixture with the 

 common air : and when the miners approach it with 

 lighted candles or lamps, it inflames with a tre- 

 mendous explosion, killing the workmen and de- 

 stroying the works. Indeed, nothing can be more 

 terrible than such accidents ; and there is reason 

 to think that they have happened more frequently 

 than is generally known. The body of miners are, 

 therefore, infinitely indebted to Sir Humphry 

 Davy for his invention of the Safety-lamp, an in- 

 strument which they can carry lighted into an ex- 

 plosive mixture, without any danger of setting fire 

 to it. This gas is called the Fire-damp by the 

 miners. 



Bi'Carbureted Hydrogen. ■ — This gas contains 



