504 



APPARATUS FOR 



about one grain of the new powder was exploded 

 at the top (A). The flame was seen to dart 

 through the flannel. The flannel, when examined 

 after the discharge, had not the slightest appear- 

 ance of having been scorched ; it was, however, 

 blackened a little at the spot through which the 

 flame had passed. 



Experiment 9. — The 8th experiment was re- 

 peated with several pieces of flannel at once. Af- 

 ter each discharge with the flannel doubled, the in- 

 terior piece was a very little scorched, but the ex- 

 terior one appeared as formerly. When three 

 pieces of the flannel were put at the bottom of the 

 tube, the flame seemed with difficulty to pierce 

 them ; the interior flannel was more scorched than 

 took place with the two pieces only, and part was 

 entirely gone ; the middle flannel was also slightly 

 scorched. When four pieces of flannel were used, 

 the interior two were much burnt, and the third a 

 little ; but the flame did not pierce through the 

 fourth piece. When this last was several times re- 

 peated in a very dark situation, there could not be 

 discovered the slightest appearance of the flame at 

 the bottom of the tube. 



Experiment 10. — When two pieces of thin 

 coarse paper were put at the bottom of the tube 

 (B), and the powder was exploded as before, the 

 flame passed through, making a rent in the paper, 

 without burning it in the least. When the paper 

 was examined, it presented, on each side of the 



