5I04 Dr. Clanny on the Means of procuring 



boy of common understanding. It is so strong, that should 

 large pieces of coal fall upon it, they cannot in the least injure 

 it. Nor is there any chance of its being upset by any acci- 

 dent, as it may be worked at the very bottom of the mine; and 

 it is likewise conveniently portable. 



The combustion of the candle, within the lamp, is supported 

 by the ordinary atmospheric air of the coal mine, which is 

 supplied by a pair of common bellows through a stratum of 

 water below the candle ; at the same time a portion of the air 

 already in the lamp, is driven through another stratum of 

 water above the candle, and thus the air supplied may explode 

 within the body of the lamp, without communicating the effect 

 to the air in the mine, however highly it might be chairged 

 with carburetted hydrogen gas. 



The moment the air enters into the lamp, it comes in con- 

 tact with the candle, and consequently, upon all occasions, a 

 small portion only of the air can be exploded, instead of the 

 whole contents of the lamp ; by these means several obvious 

 advantages are secured. The air passing in a brisk current 

 from below upward, close by the candle, carries the snuff with 

 it, so that the light is always clear and steady, 



I may also remark that wherever a person can exist from 

 a sufficiency of atmospheric air, this lamp will afford a safe 

 and abundant light, from one candle only, for the space of five 

 hours at least. This lamp will, in all probability, be found 

 very useful in the powder magazines of ships of war, and of 

 forts, as also in those places where gunpowder is manufac- 

 tured ; but this observation is merely thrown out for the opi- 

 nion of those who are more conversant upon such subjects. 



