SCIENCE OF THE DAY.

New Zealand Herald, Volume LXVII, Issue 20472, 25 January 1930, Page 5 (Supplement)

SCIENCE OF THE DAY.

WONDERS OF THE MOLECULE : / At the annual meeting of the Royal Society, held in London, on November 30, the president, Sir Ernest Rutherford, spoke on recent scientific investigation into the constitution and action of molecules. In the main, tho lecture was concerned with (1) Changes observed in tho quality of light by scattering; (2) The discovery tjiat hydrogen, hitherto regarded as the simplest moleculo known to us, Actually consists of two kinds of molecules.

, According to the summary published, Sir Ernest observed that the rapid advance of knowledge in physics had been a most marked feature of the last decade. This was mainly due to the close combination of theory with experiment. That interaction was clearly marked in the subjects lie had chosen for discussion. As far back as 1871, the late Lord Rayleigh, investigating the blue colour of the sky, had suggested that it was due mainly to the scattering of sunlight by molecules of the atmosphere in its path, and not necessarily to reflection from intruding dust particles. This theory of molecular scattering was strikingly confirmed by the present Lord Rayleigh, who had shown that scattering of light could be observed in gases freed from all dust nuclei. Of recent years, many additional experiments had been made. Notably Sir Chandrasakara Raman, of the University of Calcutta, had observed that when monocromatic light of a definite frequency was passed through certain organic liquids,, carefully purified, tho colour of the scattered light distinctly differed 'from that of the incident beam. In some way the light had been altered by the scattering of tho molecules in the liquid. As this scattered light was passed through a spectroscope, a striking result was observed. While the strongest line was found equal in frequency to tho incident light, as was to be expected, in addition there appeared many new lines, on the low-frequeucy and high frequency sides of tho strong line. Tho discovery promised to open up a new field of experimental enquiry, and throw valuable light on the modes of vibration and constitution of tho chemical molecule. On the subject of recent experimental research into molecular constitution of hydrogen, Sir Ernest Rutherford, said that within the past year it had been