Mass-loss from red-giant stars has been proved by optical observations of violet displaced absorption cores in strong metal lines of low excitation (Deutsch, 1956) long before vast circumstellar shells around the most luminous stars were detected by infrared radiation from circumstellar dust (Gillet et al. 1968, Woolf and Ney, 1969), by intrinsic polarization of star light (e.g., Serkowski, 1966) and by molecular microwave emission (Wilson and Barrett, 1972). Hot expanding coronae which emit UV

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... lines of highly ionized metals were detected only recently in G and K giants (e.g., β Gem, Gerola et al., 1974).