. Manual of the natural history, geology and physics of Greenland and the neighbouring regions / prepared for the use of the Arctic expedition of 1875, under the direction of the Arctic Committee of the Royal Society and edited by T. Rupert Jones. Together with Instructions suggested by the Arctic Committee of the Royal Society for the use of the expedition / published by authority of the Lords Commissioners of the Admiralty [microform]. Natural history; Scientific expeditions; Sciences naturelles; Expéditions scientifiques. fT"^' 732 THE AURORA BOREALIS. H â ' i't i if -,.4! 4 I ft 'I.
. Manual of the natural history, geology and physics of Greenland and the neighbouring regions / prepared for the use of the Arctic expedition of 1875, under the direction of the Arctic Committee of the Royal Society and edited by T. Rupert Jones. Together with Instructions suggested by the Arctic Committee of the Royal Society for the use of the expedition / published by authority of the Lords Commissioners of the Admiralty [microform]. Natural history; Scientific expeditions; Sciences naturelles; Expéditions scientifiques. fT"^' 732 THE AURORA BOREALIS. H â ' i't i if -,.4! 4 I ft 'I. I do not know if those several phases of the positive part of the discharge have all been examined spectroscopically. They pass into each other according to the shape and size of the tube or flask, as well as the air-pressure ; and it is difticult lo say liow much of each is concerned in those observations Avhich have been made of air-spark spectra in comparison with the aurora. No one, so far as I knoAV, has compared with it the 7ieffative-g\o\y spectrum so fully as Angstrom has now done; and it seems very probable that its peculiar fitness for the comparison has been overlookedâthe feat of filling n bottle with the negative glow discharge being certainly a novelty; if it is really true that ho succeeded in obliterating the positive brush entirely in its favour. The next remarkable novelty in the paper is tlie way in which he proposes to account for the " citron" line of auroras; for there is evidently nothing of the kind in the negative glow, how- ever well that answers to all the secondary facts of faint blue, red, and greenish lines. If oxygen and its compounds arc (as has, I believe, been lately shown) strongly jluorcsccnt^ Tait and Dewar have also proved, as shown by some of their experiments this year, that they also possess powers of phosphorescenceâGeissler tubes shining for some time after the spark has passed through them, from the production of ozone
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Keywords: ., bookcentury1800, bookdecade1870, books, booksubjectnaturalhistory
