"We saw that the Bohr model was able to correlate the observations of Angstrom, which had been formulated by Balmer. And, furthermore, the concept of energy level quantization was observed in mercury during the course of the Franck-Hertz experiment giving credence to the notion that quantization of energy levels is not the property of one-electron atoms alone but is something that is more broadly applicable.

So Bohr was validated in very, very strong measure, but there were also some contrary data. And we saw those. First there was the observation by Michelson who back in the late 1880s had done very precise interferal metric measurements of the hydrogen lines and had observed that the 656 nanometer line associated with the transition of n equals 3 to n equals 2 was, in fact, a doublet..."