Abstract
LONDON.
Royal Society, March 14.—Sir Archibald Geikie, K.C.B., president, in the chair.—Prof. E. Goldmann: A new method of examining normal and diseased tissues by means of intra-vitam staining. The author's original method of intra-vitam staining by injection of trypan and isamin blue has been greatly advanced in several points described.—Dr. E. K. Martin: The effects of ultra-violet rays on the eye. Three lines of investigation have been taken and carried out, in each case on rabbits:—(1) Absorption.—Using an iron arc as the source of light and a quartz spectrograph, the absorption of the media of the eye was found to be as follows:—Cornea.—All rays of wave-lengths less than 295 μμ are cut off completely. Lens.—Absorption commences at 400 μμ and is complete beyond 350 μμ. Vitreous.—Shows a broad absorption band with ill-defined margins extending from 280-250 μμ. All the media were found to be uniformly permeable to rays between the wave-lengths 660-400 μμ. (2) Results of repeated exposure of eye to light containing a high proportion of ultra-violet rays. A series of animals were exposed at repeated intervals for from three to twelve months. They showed marked inflammatory reaction in the cornea and conjunctiva, and in one case a proliferation of the cells of the anterior lens capsule. (3) Transmission of hasmolysins to aqueous humour after exposure of eye to short wave-length rays. The aqueous of animals which have been sensitised to the blood of another species has no power of hasmolysing- red blood-corpuscles of that species. After exposure of the eye of such an animal to the quartz mercury vapour lamp, the aqueous becomes actively hasmolytic, and remains so for a period not as yet determined, but in any event longer than the duration of the resulting inflammatory changes.—Dr. W. S. Lazarus-Barlow: The presence of radium in some carcinomatous tumours. Elsewhere the author published evidence that acceleration of electroscopic leak may be produced by the residue of carcinomatous tissue after its extraction with ether and subsequently with water, or after extraction with acetone. The results were criticised as being small, and as possibly explicable by alteration in capacity of the electroscope occasioned by introduction of the substances within it. The subject was therefore reinvestigated with an electroscope of constant capacity in which a fixed wire grating separated the portion containing the gold-leaf rom the portion into which the substances were introduced. Twenty-seven samples of primary carcinoma, eight of secondary carcinoma, two sarcomata, and five normal livers and lungs were examined under these conditions, and the original conclusion was confirmed.—C. Russ: An improved method for opsoriic index estimations involving the separation of red and white human blood corpuscles. The observed errors by the improved method were one quarter the magnitude of those by the old process, the conditions of experiment being almost completely comparable.—Prof. W. M. Thornton: The electrical conductivity of bacteria, and the rate of inhibition of bacteria by electric currents. Tap water containing B. coli communis can be completely sterilised by direct currents in several hours at 0·2 ampere sq. cm. Alternating currents sterilise water nearly, if not quite, as well as direct currents having the same current-density. Milk is curdled by direct current at the positive pole and thinned at the negative pole. Milk can be sterilised without curdling by passing alternating current, this being largely thermal. The cause of the marked' bactericidal action of light is suggested to be syntony between it and the frequency of electronic rotation in the atoms of protoplasm.—E. C. Hort and W. J. Penfold: A clinical study of experimental fever. Conclusions: (1) That the establishment as separate entities of these various types of fever no longer rests on secure ground; (2) that future advance in the experimental study of fever is not possible unless precaution be taken to ensure that the water or saline used for injection is free from the fever-producing body described.—S. G. Shattock and L. S. Dudgeon: Certain results of drying non-sporing bacteria in a charcoal liquid air vacuum. The bacteria used comprised B. coli, B. typhosus, Staphylococcus pyogenes aureus, B. pyocyaneus. The action of light was excluded during the experiments. B. typhosus and B. coli died both in vacuo and in air-dried slips within five days. S. pyogenes aureus persists considerably longer under both conditions. The interest centres around B. pyocyaneus. Air-dried films did not survive beyond nine days. The slips kept in vacuo were alive at seven months. B. pyocyaneus was submitted in vacuo to the action of heat, and also to the sun's rays (the sealed vacuum tubes being submerged in water). Its 1 resistance to these agencies, in the dried state, in vacuo, was not materially, if at all, increased. The bacillus was killed, moreover, by the action of ultraviolet rays on being removed from the vacuum and treated in an atmosphere of nitrogen. So far as the possibility of interplanetary bacterial life is concerned, it is evident that bacteria in the fully dried state, if free in the interplanetary vacuum, would be killed by the sola' light. As Sir James Dewar's experiments have demonstrated that the ultra-violet rays will kill undried bacteria whilst in the frozen condition at the temperature of liquid air, there is little to support the hypothesis that the living protoplasm on the earth originally immigrated from interplanetary space in a free or unincluded condition-that free, particulate life has entered the earth's atmosphere, as a result of light propulsion, from extramundane space.
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Societies and Academies . Nature 89, 76–79 (1912). https://doi.org/10.1038/089076a0
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DOI: https://doi.org/10.1038/089076a0