DISCHARGING OF OllDNANCE. 505 



hole, the separated threads, as if it had been torn 

 with the hand. When four pieces of paper were 

 used, the flame did not pass through them. 

 When paper and flannel were used at the same 

 time, it was found that the interior one was always 

 a little scorched. 



From several of these results it would appear, 

 that when the flame proceeds with great velocity, its 

 power of acting upon inflammables or other substan- 

 ces is so prevented ; but wherever we, by any means, 

 retard that motion, we facilitate its action. In the 

 eighth experiment noticed, when one piece only of 

 flannel was used, the flame passed through without 

 scorching it ; but we find, in the ninth experiment, 

 that as we add to the resistance by additional pieces 

 of flannel, we have the more of the scorched effect. 

 The same was illustrated in the tenth experiment, 

 when a piece of paper was put below one piece of 

 flannel, and when the flannel was put below the pa- 

 per. This was also proved by the phenomena of the 

 four first experiments. 



Experiment 11. — Independent of the proposed 

 application of the apparatus, it appeared of consi- 

 derable importance to ascertain the distance to 

 which flame could thus be propelled. On this ac- 

 count I affixed to the apparatus a tube 26 inches 

 long ; after numerous trials with this, and with 

 tubes of decreasing lengths, I found that no flame 

 appeared at the bottom, till the tube was shortened 



