60 SECTIONAL ADDRESSES. 
forms of radiant energy as electromagnetic phenomena. Now that the 
physicists have brought physical science back to the close and intimate 
study of matter, physics and chemistry have come together again, and 
the old and homogeneous science of ‘ natural philosophy ’ has been 
reconstituted. It is time that the walls which divide our chemical and 
physical laboratories were broken down, and that the young men and 
women who come to our Universities to study physics or chemistry, 
should study the facts and principles of a fundamental science which 
includes both. 
Since the last meeting of our Section a number of eminent men 
of science have passed away. It is with great sorrow that I record the 
deaths of Professor Sir James Dewar, F.R.S., in our own country, and 
of Professors E. Beckmann, J. P. Kuenen, G. Lemoine, L. Vignon, 
and J. D. van der Waals on the Continent. Limits of time and space 
forbid me to attempt here any account of the great services to science 
rendered by these eminent men. As the successor of Tyndall, Sir 
James Dewar worked for over forty years at the Royal Institution, and 
by his investigations on the liquefaction of gases and the physical and 
chemicial behaviour of substances at low temperatures, upheld the 
famous tradition of the Royal Institution as a home of pioneer research 
in science. Beckmann’s name is well known for his researches on the 
effect of dissolved substances on the boiling- and freezing-points of 
solvents, and for the convenient form which he gave to the ‘ variable 
zero’ thermometer. He also devised useful and convenient forms of 
apparatus required in spectroscopic work. Lemoine was one of the 
pioneers in the study of chemical reaction velocities and equilibria in 
France, whilst Vignon was well known for his researches in organic 
chemistry. Kuenen was at one time Professor of Physics at Dundee, 
although at the time of his death he had been for many years one of 
the Professors of Physics at Leiden. He was particularly noted for 
his investigations on the equilibria occurring in the evaporation and 
condensation of liquid mixtures. His death at a comparatively early 
age is a very heavy loss to science in general, and to Holland in 
particular. In van der Waals there passes away one of the very greatest 
men of science. He was one of that group of Dutch men of science, 
including Cohen, Lorentz, Kamerlingh Onnes, van’t Hoff, Roozeboom, 
Schreinemakers, and Zeeman, who have made Holland so famous as a 
centre of physical and chemical research during the last thirty or forty 
years. Van der Waals was the great mathematical and physical inter- 
preter of the work begun by Thomas Andrews. 
In recent years a great deal of attention has been paid by chemists, 
physicists and physiologists to the phenomena which occur at the 
surfaces or interfaces which separate different sorts of matter in bulk. 
During the last quarter of the nineteenth century, both J. Willard Gibbs 
and J. J. Thomson had shown clearly, though in different ways, the 
peculiar nature of these interfacial or transitional layers. It was 
evident that things could happen in these regions which did not occur 
in the more homogeneous and uniform regions well inside the volume 
of matter in bulk. Such happenings might, if they could be investi- 
gated, reveal molecular or atomic peculiarities which would be undetect- 
