Abstract
DUBLIN Royal Irish Academy, April 24. P. J. NOLAN: The influence of condensation nuclei and dust particles on atmospheric ionisation. Fair conformity with Wright's conclusion that dust particles play an important part in the equilibrium of atmospheric ionisation is obtained from a re-examination of previous work. A theoretical basis for the equilibrium equation q = ζnνZ is proposed. The combination coefficients of small ions with dust particles and with large ions are deduced. R. F. SCHARFF: The past wanderings in Europe of two African animals. The manner in which the hippopotamus and the bivalve mollusc Corbicula seem to have entered Europe from the south-east in late Pliocene times is described. They probably travelled along the great Rift Valley from Central Africa to Palestine when the Red Sea was still a river valley. The area of the Ægean Sea, while still unsubmerged, afforded an easy passage between Asia Minor and Greece and thus on to Italy and Malta. Their remains occur everywhere in Italy, France and Belgium, but the hippopotamus never crossed the Rhine. Eventually, in the early Pleistocene, both species passed into England, when it was part of the Continent. Special comment is made on the significance of the British distribution of both animals.
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Societies and Academies. Nature 131, 922–924 (1933). https://doi.org/10.1038/131922a0
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DOI: https://doi.org/10.1038/131922a0