December 7, 1905] 



NA TURE 



131 



Panels high among the great philosophical chemists of the 

 last century. As early as 1856 he published his own con- 

 clusion that paramagnetic elements have, in general, 

 smaller molecular volumes than diamagnetic elements, and 

 confirmed Avogadro's view that electropositive elements 

 have larger molecular volumes than electronegative ones, 

 both of them results specially interesting in connection 

 with modern views of molecular structure. At that time 

 he had already assimilated and utilised the views of 

 Laurent, Gerhardt, and Williamson on molecular constitu- 

 tion, which made such slow progress in general. Since 

 then, in the words of Dr. Thorpe (Nature, June 27, 1889), 

 " There is, in fact, no section of chemical science which 

 he has not enriched by his contributions" — mineralogy, 

 chemical geology, organic chemistry, the nature and in- 

 dustrial importance of petroleum, but, above all, physical 

 chemistry and chemical philosophy. 



Quoting again from Dr. Thorpe : — " His ' Principles of 

 Chemistry,' published in 1889, and repeatedly reprinted, is 

 a veritable treasure-house of ideas, from which investigators 

 have constantly borrowed suggestions for new lines of 

 research. This book is one of the classics of chemistry ; 

 its place in the history of science is as well assured as the 

 ever-memorable work of Dalton." In the course of its 

 preparation he developed the great generalisation known as 

 the periodic law of the elements, with which his name will 

 ever remain most closely associated, especially as a weapon 

 For predicting new elements, and for which he has received 

 the Davy medal of this society, as also have Newlands 

 and I.i thar Meyer for their independent advances in the 

 same direction. 



This law has changed the face of chemistry by impart- 

 ing to the study of its numerous independent elements that 

 close inter-connection which is a characteristic of advanced 

 physical theories. 



Royal Medals. 



\ Royal medal is awarded to Prof. John Henry Poynting, 

 I . K.S., on account of his researches in physical science, 

 especially in connection with the law of gravitation and the 

 theories of electrodynamics and radiation. 



Prof. Poynting is distinguished both in theoretical and 

 experimental physics. His memoir, Phil. Trans., 1884, 

 " On the Transfer of Energy in the Electromagnetic 

 Field," contains the fundamental proposition which is now 

 universally known as Poynting's theorem. It was followed 

 in Phil. Trans., 1885, by a paper " On the Connection 

 between Electric Current and the Electric and Magnetic 

 Inductions in the Surrounding Field," which works out 

 the current circuit on the supposition of motion of what 

 are now called Faraday tubes. These papers served greatly 

 in elucidate .Maxwell's theory, and give a representation of 

 th'- physical nature of the electric field which is now widely 

 utilised. His long-continued experimental and theoretical 

 re-earches on the constant of gravitation and on the mean 

 density of the earth are reported in a paper in the l'hil. 

 Trans., 1892, and in the Adams prize essay for 1893. 

 Closely related to this subject is an experiment in seari li 

 of a directive action of one quartz crystal on another, Phil. 

 Trans., 1899, which, though leading to a negative result, 

 is a model of the application of refined methods to a 

 physical research of great delicacy. His recent paper, 

 Phil. Trans.. 1903, "On Radiation in the Solar System, 

 its Effect on Temperature, and its Pressure on Small 

 Bodies," is of great interest and significance in cosmical 

 physics. He is the author of various theoretical papers on 

 physicochemical subjects, such as change of state and 

 osmotic pressure, which are conspicuous for originality of 

 conception and clearness of exposition. 



The other Royal medal is awarded to Prof. Charles Scott 

 Sherrington, F.R.S., for his work on the central nervous 

 system, especially in relation to reflex action. 



Prof. Sherrington has published a series of important 

 papers upon the structure and function of the brain and 

 spinal cord. In the earlier of these he chiefly investigated 

 the course of the several groups of nerve fibres by means 

 of the degeneration method. Passing from the study of 

 structure to that of function, he discovered that removal 

 of the fore brain causes a widespread rigidity of certain 

 muscles, which he called decerebrate rigidity. In the state 

 of decerebrate rigidity, the ordinarily observed reflexes of 



NO. 1884, VOL. 73] 



the bodv become profoundly altered, and a study of the 

 normal and abnormal reflexes led him to the observation 

 that contraction of one muscle is commonly associated 

 with inhibition of its antagonist. Upon this he formulated 

 the law of the reciprocal action of antagonistic muscles, 

 which is now accepted as of fundamental importance in 

 the coordination of muscular movement. A further study 

 of reflex actions led him to lay down certain general prin- 

 ciples with regard to them. One principle deserves especial 

 mention, namely, that hurtful stimuli applied to the skin 

 produce a different form of reflex from that given by 

 stimuli which are not hurtful. This has served as a basis 

 for further investigation on the character of the nerve 

 impulses conveyed by different nerve-endings, on the course 

 t. ilven by the impulses, and on their central connections. 



In recent vears a considerable amount of work has been 

 done in mapping out the areas of the skin supplied by each 

 of the cranial and spinal nerves. This work, essential 

 both to physiology and to clinical medicine, reTeived its 

 chief impetus and most weighty contribution from the 

 careful and detailed observations of Prof. Sherrington. 



The researches of Prof. Sherrington and Dr. Grunbaum, 

 on the localisation of the excitable areas in the cortex of 

 the cerebral hemispheres in the higher apes, have resulted 

 in placing the " motor area " in this animal entirely in 

 front of the central sulcus. The result is now generally 

 accepted as true also fur the brain of man — a point of 

 great importance in the surgery of the brain. 



Prof. Sherrington's researches have dealt with a number 

 of subjects cognate with that of the central nervous system. 

 He has shed light on questions connected with the afferent 

 nerves of skeletal muscle, the efferent nerves of the arrec- 

 tores pilorum and of the cranial blood-vessels, the inner- 

 vation of various viscera, the trophic centre of the fibres 

 of the roots of the spinal nerves, the knee jerk, and with 

 the physiology of vision. 



Davy Medal. 



The Davy medal is awarded to Prof. Albert Ladenburg, 

 on account of his researches in organic chemistry, especially 

 in connection with the synthesis of natural alkaloids. 



Thirty vears ago, when the validity of Kekule"s famous 

 formula for benzene was the subject of much discussion, 

 Ladenburg was the first to prove, by laborious research, 

 the important proposition that the six hydrogen atoms in 

 the hydrocarbon are similarly situated and discharge the 

 same functions, and hence that three, anil only three, 

 di-substitution derivatives can exist. 



He has also devoted many years to the study of the 

 natural alkaloids. This pioneer work, attended by many 

 experimental difficulties, was rewarded by success in the 

 synthesis, for the first time in 1886, of an optically active 

 compound identical with the alkaloid coniinc existing in the 

 hemlock plant. Since that time he has largely added to 

 our knowledge of the chemistrj of hyoscyamine, atropine, 

 and other alkaloids of the mydriatic class. 



Hughes Medal. 



The Hughes medal is awarded to Prof. Auguslo Righi, 

 for his experimental researches in electrical science, in- 

 cluding electric vibrations. 



Prof. Righi has been for many years a prominent and 

 active worker in the sciences of light, electricity, and 

 magnetism. 



Among the subjects which have engaged his attention are 

 the Hall effect, and the change of electric conductivity of 

 bismuth in a magnetic field. At an early period he carried 

 out an elaborate investigation on the reflection of light at 

 the surface of a magnetised body, repeating and extending 

 Kerr's observations with more powerful apparatus ; in par- 

 ticular, he showed how the amount of the rotation of the 

 plane of polarisation depends upon the wave-length of the 

 light. 



A valuable series of papers related to phenomena pro- 

 duced by the ultra-violet rays, including the first discovery 

 of the discharge of negative electricity from a freshly 

 polished zinc surface under their influence. He has also 

 investigated the potential in the neighbourhood of the 

 kathode in a Crookes's tube, and made many experiments 

 on the spark discharge in gases and the action of the 

 Rontgen rays. 



