抄録
1. Employing Lo Surdo's method, the effect of an electric field on the spectrum lines of helium and hydrogen was investigated.
2. For Hγ, the central line in the perpendicular component was found to be shifted about 1Å toward the red side in a field of 130000voit/cm.
3. For helium lines, including the results previously published by one of us with Mr. Yoshida, and marked by asterisks, the Stark effect on the following 26 lines were examined in all 6678, 5876, 5048, 5016, 4922. 4713, 4686, 4518, 4472, 4438 4388, 4169. 4144, 4121, 4046, 4026, 4009, 3965, 3889, 3868 3830, 3820, 3614, 3448, 3188, 2945
For the seven lines printed in heavy type in the above table, the effect has not been observed by other investigators.
4. The lines 4438, 4121 and 3965, which had hitherto been said to be merely shifted by an electric field, were found to be resolved into a number of components, all being shifted in the same direction.
5. A striking similarity was noted in the Stark effect on 4388, 4026 and on the hydrogen line Hγ, on the following points:
a) The central line in the s-component is the strongest of all the components
b) The said line is shifted toward the red as the field strength is increased.
6. Advantages of using an echelon grating for examining the Stark effect are discussed.
