XXX. 
ON THE THEORY OF THE STRATIFIED DISCHARGE IN 
GHISSLER TUBES. By H. V. GILL, 8.J., Clongowes Wood 
College, Co. Kildare. 
[COMMUNICATED BY PROFESSOR W. F. BARRETT, F.R.S.| 
[Read Frsruary 7 ; Received for Publication Fenruary 22; Published 
June 5, 1901.] 
In a somewhat recent number of the ‘“ American Journal of 
Science’! I published an article dealing with the stratified dis- 
charge, in which I suggested a possible explanation of this curious 
phenomenon. As the question is an interesting one, I hope I 
may be allowed to state briefly the result of a further consideration 
of the matter. 
In the Paper referred to I gave some reasons for supposing 
that the strata were due to certain mechanical disturbances caused 
in the body of the gas by the explosion of the spark. A number 
of experiments were described which went to establish a relation 
between the stratified discharge and the well-known experiment 
of Kundt, in which the position of nodes is shown by heaps of a 
light powder which are formed at certain places in the tube, when 
the column of air inside it is made to vibrate by some source of 
sound waves. When the length of the tube is an exact multiple 
of the half wave-length’ of the note the powder collects at the 
nodes. In addition to the true nodal lines there are also other 
short transverse lines which Lord Rayleigh* thus describes :— 
*‘ Perhaps the most striking of all the effects of alternating aerial 
currents is the rib-like structure assumed by cork filings in Kundt’s 
experiment. Close observation, while the vibrations are in pro- 
gress, shows that the filings are disposed in thin laminz transverse 
to the tube and extending upwards to a certain distance from the 
bottom.” Tyndall, and in fact all who have studied the ex- 
periment, have remarked the fact that these lines do not appear 
in Kundt’s experiment when the tube is an exact multiple of the 
1 Vol. v., 4th Ser., June, 1898, pp. 399-417. 
2 Lord Rayleigh, ‘‘ Sound,”’ vol. ii., p. 58. 3 Tbid., p. 46. 
SCIENT. PROC. B.D.S., VOL. IX., PART IV. 2G 
