Lockyer, Norman, Sir, 1836-1920. n 86860325 · London : Kegan Paul. Trench, Trubner & Co. · leaf 91
Methods of Demonstration. Bunsen’s battery, was placed opposite one end of the tube, and a spectroscope (G) opposite the other. (Fig. 26.) … When it is desirable to increase the length of the column of vapour, a tube some centimetres long is
Spectrum analysis · Color
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