Dr. E/. Konig on Manometric Flames. 



If the pressure derived from the manometric capsule pass 

 through the entrance-tube towards the gas-reservoir, it will be 

 annulled when entering the accessory capsule by the yielding of 

 the membrane. 



Practice shows that we may put into the strongest motion one 

 of several flames isolated in the foregoing manner without in any 

 way affecting the rest. 



Proof of the different condition of the Air in the Nodes and 

 Ventral Segments of a sounding Air-column. 



In order to show the changing density of the air in the nodes 

 and its fixed condition in the ventral segments of a sounding air- 

 column generally, I make use of an open organ-pipe, which is so 

 constructed that either its fundamental tone or its first harmonic or 

 overtone, the octave, can be sounded at will (fig. 1). At the node 

 of the fundamental and the two nodes of the 

 octave are three orifices in one side of the pipe ; Fig. 1. 



over these three manometric capsules are so 

 placed that the orifices are exactly closed by 

 the membranes, being of the same diameter; a 

 common reservoir, provided with accessory 

 capsules, feeds the three flames, the length 

 of which can be regulated by cocks. 



If, now, we give to the three flames an equal 

 height of 15 to 20 millimetres, and sound 

 the octave, then the two exterior flames will 

 be put into such violent motion that they 

 will appear prolonged, narrow, quite blue, and 

 without illuminating power, on account of 

 the considerable amount of air which they 

 draw with them in their flickering up and 

 down, whilst the middle flame will remain 

 almost still and bright, being placed at the 

 centre of a ventral segment, where the air is 

 only gliding to and fro. 



At the sounding of the fundamental the 

 middle flame is at the node, and therefore vio- 

 lently agitated ; the two exterior ones, which 

 are then between the node and the centres of 

 the ventral segments at the ends of the pipe, 

 show only a weaker motion. As in this case 

 it is only a question of different intensity of 

 motion in the individual flames, it is better 

 here to make use of smaller flames, when the 

 middle one becomes quite blue, while the 

 exterior ones remain bright. If we give the 



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