PROCEEDINGS 
OF THE 
NATIONAL ACADEMY OF SCIENCES 
Volume 8 JUNE 15. 1922 Number 6 
CYLINDRICAL DISTRIBUTION OF NODAL STRENGTH AROUND 
THE PIPE NORMAL* 
By Cari. Barus 
DEPARTMENT OF PhYSICvS, BroWN UNIVERSITY 
Communicated, April 14, 1922 
1. Circular and Radial Survey. — The unexpected non-symmetric results 
obtained in the last paper, induced me to try a group of experiments rel- 
ative to the center (nearly) of the table. The resonator was therefore 
carried in a circle of radius fR around the plumb line let fall from the 
mouth of the pipe. The measurements were then repeated for successive 
levels of the pipe (0p = 40 cm. and 50 = X cm. nearly) and of the reso- 
nator (^R =0, 12 = X/4, 24 = X/2 cm.). The relation of the 
different locations is suggested by the inset of figures 1, 2, which is a re- 
duced plan of the room, with the pipe in the vertical above P on the table. 
The directions -f y (west) and — x (south) are thus toward walls, 
whereas -f x (north) and — y (east) are largely toward open spaces from 
the table. 
In the first exploration (here omitted) the mouth of the pipe P was Zp 
— 40 cm. above the table. Carrying the mouth of the resonator on the 
table with its axis kept parallel to x, around successive circles of radius r^ 
