;S6 



NA TURE 



[February 14, 1901 



SOCTETIES AND ACADEMIES. 

 London. 



Royal Society, February 7.—" On the Proteid Reaction of 

 Adamkiewicz. with Contributions to the Chemistry of Glyoxylic 

 Acid." By F. Gowland Hopkins, M.A., M.B , University 

 Lecturer in Chemical Physiology, and Sydney W. Cole, B.A., 

 Trinity College. (From the Physiological Laboratories, Cam- 

 bridge.) Communicated by Dr. Langley, F.R.S. 



The proteid reaction described by Adamkiewicz is not a fur- 

 furol reaction, but depends upon the presence of small quantities 

 of an impurity in the acetic acid employed. Some specimens of 

 acetic acid yield no reaction, and all may be deprived of chromo- 

 genic power by distillation. 



The substance essential to the reaction is glyoxylic acid. 



Small quantities of glyoxylic acid are produced during the 

 oxidation of acetic acid by hydrogen peroxide in the presence 

 of ferrous iron. Under the conditions used in this research, 

 part of the glyoxylic acid thus formed is split up, yielding 

 formaldehyde. 



Glyoxylic acid is slowly formed when acetic acid stands in the 

 air, and more rapidly in the presence of ferrous iron and under 

 the influence of direct sunlight. Most specimens of acetic acid 

 contain small amounts of glyoxylic acid as an admixture. 



A dilute aqueous solution of glyoxylic acid, which may be 

 readily prepared by the reduction of oxalic acid with sodium 

 amalgam, forms an admirable test for proteids when used instead 

 of acetic acid under the ordinary conditions of the Adamkiewicz 

 test. 



"Further Investigations on the Abnormal Outgrowths or 

 Intumescences in Hibiscus vilifolius, Linn. : a Study in Experi- 

 mental Plant Pathology." By Elizabeth Dale. Communicated 

 by Prof. H. Marshall' Ward, F.R.S. 



The conclusions drawn from the experiments are that the out- 

 growths are formed in a moist atmosphere, provided that there 

 is also adequate light and heat. 



The immediate effect of the damp atmosphere is to check 

 transpiration. This, in its turn, by blocking the tissues with 

 water, disturbs the normal course of metabolism, and so leads 

 (when the light and heat are sufficient) to changes in the 

 metabolic activity of the plant, as is shown by the following 

 facts : — 



(i) The outgrowths only develop if transpiration is reduced. 



(2) The outgrowths are chiefly formed on organs which are 

 actively assimilating, e.g. under ordinary red or yellow glass ; 

 but only if transpiratory activity is lowered : they are not formed 

 in the open. 



(3) They only occur {ceteris paribus) in plants in which there 

 is an accumulation of starch. 



(4) They are formed under clear glass and under red and 

 yellow glass, but not under blue or green glass, and in no case 

 in darkness. 



(5) Their formation is accompanied by the production of oil, 

 which is not found in normal leaves. 



(6) The presence of this oil suggests that events similar to 

 those occurring in succulent plants are taking place, viz., reduced 

 respiration and the development of osmotically active substances 

 in excess. 



(7) It is therefore probable that the intumescences are due to 

 the local accumulation of osmotically active substances, produced 

 under the abnormal conditions, viz., reduced transpiration and 

 consequent lack of minerals, while. carbohydrates are being 

 developed in excess. 



Physical Society, February 8. — Annual General Meeting. 

 Mr. G. Griffith, Vice-president, in the chair. The report of the 

 council was read and adopted. Prof. Willard Gibbs and Dr. 

 Rudolph Koenig were elected to the two vacant honorary 

 fellowships of the Society. The following officers and council 

 were elected for the ensuing year : — President : Prof S. P. 

 Thompson. Vice-presidents (members who have filled the 

 office of president) : T. H. Blakesley, C. V. Boys, Prof. J. D. 

 Everett and J. Walker. Secretaries: H. M. Elder and W. 

 Watson. Foreign Secretary : Dr. R. T. Glazebrook. Treasurer : 

 I'rof. H. L. Callendar. Librarian : W. Watson. Other mem- 

 bers of the Council : Prof Armstrong, W. R. Cooper, G. 

 Griffith, E. H. Griffiths, Dr. R. A. Lehfeldt. S. Lupton, Prof. 

 Perry, Dr. Porter, W. A. Price and R. Threlfall.— Prof. S. P. 

 Thompson then took the chair and delivered an address. In 

 opening, the President gave in detail the various ways in which 

 the aim of the Physical Society to promote the progress and 



NO. r633, VOL. 63] 



study of physics has been accomplished during the twenty-six 

 years of tlie Society's existence. Referring to the election of two 

 honorary fellows, Prof. Thompson said they had added to 

 their roll two men distinguished in very different walks of 

 physics. Prof. Willard Gibbs is a United States mathematical 

 physicist whose work in thermodynamics, elastic solid theory of 

 light and other specialised subjects is of the highest order and is 

 valued for its beauty and profundity. Dr. Rudolph Koenig, of 

 Paris, is known as a maker of acoustical instruments^of perfect 

 standard, tuning-forks in particular. He has, however, found 

 time to extend the borders of acou.stics, and to him we owe the 

 manometric flames, the wave syren and other instruments of 

 research. He has also published work on the facts about the 

 combinations of pure tones. The President appealed to all 

 teachers of physics in the country to make use of the Society 

 and give it their active support. It was mainly in the interest 

 of teachers and students that the Society undertook the publi- 

 cation of science abstracts. By means of the abstracts teachers 

 have at hand the latest information on the subject, and can thus 

 continually supplement their text-book knowledge. Every 

 teacher, from lime to time, devises new or improved modes of 

 presenting his subject. At the Physical Society the Fellows 

 always welcome contributions of this kind, even though there 

 may be little of actual novelty in the principles so illustrated. 

 The routine work and administrative duties of teachers, although 

 hampering their usefulness to science and diminishing their fruit- 

 fulness, prevent their attention, without intermission, to one 

 subject and produce a direction of thought over varions domains 

 of physics which is to be welcomed rather than deplored. It has 

 been the custom for Fellows of the Physical Society to bring 

 models to illustrate physical principles. This practice of 

 using models is regarded by our Continental brethren as a 

 peculiarly English matter and one that shows a sort of 

 mental constitution they do not quite understand. Models 

 have become a part of our mental lurniture. It never occurs 

 to us that there is anything unusual in the habit. Faraday 

 has used them in connection with the electrostatic field sur- 

 rounding charged bodies. Lord Kelvin has made models to 

 convey his ideas of elasticity, of the elastic solid theory of 

 matter and of the constitution of matter itself. Maxwell's 

 models of heterogeneous dielectrics and the mutual induction 

 between two circuits are well known. These models are useful 

 for teaching purposes and for enabling one to grasp that which 

 in its nature is abstract by contemplating the representation of . 

 it or its analogue in the concrete. The French physicist cannot 

 understand a complicated phenomenon until he has reduced it 

 to a mathematical equation. The British physicist must con- 

 struct a model which will produce mechanically the analogous 

 operation. Both methods are right, but judging by their fruit- . 

 fulness the method of Faraday has advantages over that of 

 Poisson. Referring to the Nesv Teaching University of London, 

 the President said that now was the time for Fellows to offer 

 suggestions for the teaching of physics. — An ordinary meeting 

 of the Society was then held.— A paper on a mica echelon 

 grating, by Prof. R. W. Wood, was read by Mr. Watson. This 

 grating occupies a position midway between an ordinary grating 

 and an echelon with thick plates. A number of sheets of mica 

 were examined with the interferometer and one selected, over a 

 considerable portion of which the fringes were straight and 

 unbroken. This portion was marked off and cut up mto rect- 

 angles. The mica was about 005 mm. thick, and the retarda- 

 tion of one of the rectangles was found to be fiity wave-lengths 

 for sodium light. Nine of these rectangles were used to form 

 the grating, and they were put in position under a microscope 

 and cemented together at the edges with sealing wax. The 

 grating space was 05 mm. The battery was mounted on a 

 square of cardboard over a rectangular opening of the same size, 

 a clear space 05 mm. wide being left to serve as the first 

 grating line of zero retardation. The number of lines was there- 

 fore ten. The resolution of the sodium lines was beyond the 

 power of the instrument, but the yellow mercury lines were 

 easily separated. The distance between the lines was one- third 

 of the distance between the spectra. For the sake of comparison, 

 a grating of the same spacing and number of lines was ruled on 

 a piece of smoked glass, and it was found that in the first order 

 the grating was unable to separate the extreme red and blue 

 ends of the spectrum. The Zeeman effect can be shown with 

 an echelon made of four interferometer plates, the li^ht being 

 the green rays from a mercury lube. The Society then ad- 

 journed until February 22. 



