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methods of lighting the mines without producing its explosion . 2 1 
Fig. 7. An argand lamp of similar construction, with safe 
air canals without the flame, and metallic gauze apertures 
within. 
Fig. 8. A tin-plate chimney top for the lamp, made safe 
by metallic gauze. 
Fig. g. A metallic gauze safe lamp. AAA. Screens of 
metallic gauze or flame sieves. BB. Wires for trimming the 
wick. 
Fig. 10 A glass tube furnished with flame sieves , in which 
a common candle may be burnt. A A. The flame sieves. 
B. A little plate of metal to prevent the upper flame sieve 
from being acted on by the current of hot air. 
The lamps burn brighter the higher the chimney. 
From my experiments it appears, that a mere narrow throat 
and opening to the metallic part of the chimney, is sufficient 
to prevent explosions from passing through the lamp, suppos- 
ing them possible ; but with the safety canals or metallic 
gauze in the chimney the security is absolute. 
The circular canals and the apertures covered with metallic 
gauze, are so much superior to tubes in practical application, 
that I have no doubt of their being generally used ; I have 
therefore given no sketch of the first safe lantern I had con- 
structed with tubes ; but substituting tubes for canals it is 
exactly the same, as that represented Fig. 1. 
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