Abstract
LONDON.
Royal Society. March 22.Sir J. J. Thomson, president, in the chair.J. C. Mottram and Dr. S. Russ: Obseivations and experiments on the susceptibility and immunity of rats towards Jensens rat sarcoma Observations have been made upon the modes of growth of Jensens rat sarcoma following inoculation. There is a gradual transition from those cases in which the tumours spontaneously disappear to those in which they grow in a uniformly progressive manner. The experimental production of the immune condition can be brought about in several ways. Animals made refractory to the growth of the tumour have been given various doses of X-rays; the effect of such irradiation upon the blood was to cause a marked reduction in the number of lymphocytes. Over suitable conditions of exposure it has been possible to destroy the immune condition and thus convert refractory into tumour-bearing animals. There is a tendency for the immune condition to be restored. Histological and other evidence is brought forward which indicates that the failure of sarcoma cells to grow in an immune animal is due to an active resistance thereto on the part of the host.S. Pickering: Problems bearing on residual affinity. It has been ascertained that the alkali metals, like the other metals previously examined, form metallo compounds isomeric with normal salts, and that, therefore, these metals may assume a valency higher than that usually exhibited by them. A class of compounds intermediate between the metallo and normal salts also exists. These are termed metallato compounds. The possibility of most metals, other than carbon and hydrogen, assuming a valency value higher than that usually exhibited by them is shown to explain (i) the constancy in the heat of substitution of CH3 for H as contrasted with want of constancy in the case of the substitution of OH or Cl for H; (ii) the fact that the heat of neutralisation of organic acids is lower than that of inorganic acids, and exhibits certain distinctive features when only partially effected; (iii) that all true acids must contain a doubly linked oxygen atom, and that the ¢apparent exceptions to the constancy of the heat of neutralisation are due to the acid not being a true acid; (iv) that the so-called normal salts of the alkali metals with organic acids are strongly alkaline, and that those with inorganic acids are feebly so; (v) that the usual method of titration of an acid by an alkali, as well as the precipitation of the acid or base Iy usual methods, fails in the presence of an organic acid; (vi) that the actual value of the heat of neutralisation constant can be explained.Prof. E. Wilson and Prof. J. W. Nicholson: Residual magnetism in relation to magnetic shielding. (i) The paper contains a further contribution to the study of the problems presented by the necessity for constructing a magnetic shield capable of reducing the earths field to an order as low as 0¢001 C.G.S. unit in a large space. The main problem not treated in earlier papers is that of residual mag-netism in the various shells of the shield, and this problem is discussed in connection with exhaustive experiments in the present paper. (ii) It is found that the ordinary process of demagnetisation of a mass of iron fails to be completely effective if, during the operation of the current which is diminished by steps and continually reversed, a constant magnetic field such as that of the earth is present at the same time.
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Societies and Academies . Nature 99, 118–120 (1917). https://doi.org/10.1038/099118b0
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DOI: https://doi.org/10.1038/099118b0