Electromagnetic Spectrum of Water

R. Weichmann. Ein Banden-Absorptionsspektrum des Wassers bei Wellenlängen von mehreren Dezimetern. Phys. Zeitschr. 22, p. 535, 1922.

In view of the discrepancies existing among the results obtained by various observers for the dispersion of water in the region of Hertzian waves, the author, at Mie’s suggestion, investigated the behavior of the refractive index and absorption of water in the range of wavelengths from 65 cm to 27 cm. The measurements were made by the method of waves in parallel wires. The waves were excited by a spark vibrator constructed according to Ruhkorff. The arrangement of the wires was vertical, owing to which the waves from the air passed directly into the water. The author succeeded in making the operation of the apparatus so reliable that, when recording resonance curves, he could make 20 readings over a length of 1 mm. During the measurements, a whole series of resonance curves was recorded, from which the positions of the nodes and decrements were determined. The refractive index and absorption were calculated in the usual way from the wavelengths in air and in water and from the increase of the decrement with the depth of penetration of the waves into the water. The curves presented show the behavior of the optical properties obtained by the author. The refractive indices are reduced to a temperature of 17° C. The absorption coefficient represents the difference between the coefficient calculated from the observations and the absorption caused by the conductivity of the water.

K. Teodorovich.