638 
sented by the president, Sir J. J. Thomson, 
as announced in last week’s issue of SCIENCE. 
The characterization of the work of the medal- 
lists, as printed in Nature, was as follows: 
The Copley Medal is awarded to Hendrik Antoon 
Lorentz, For. Mem. R. 8. Lorentz is generally 
recognized as one of the most distinguished mathe- 
matical physicists of the present time. His re- 
searches have covered many fields of investigation, 
but his principal work deals with the theory of 
electrons and the constitution of matter considered 
as an electro-dynamic problem. When Zeeman had 
discovered the effect of magnets on spectroscopic 
lines, he perceived iat once the theoretical bearing 
of the effect, which led to the discovery of the cir- 
cular polarization of the components of the lines 
split up by magnetic force. Lorentz’s name is also 
associated with that of Fitzgerald in the inde- 
pendent explanation of the Michelson-Morley ef- 
fect, from which far-reaching consequences have 
been derived. An important optical relationship 
between the density of a medium and its index of 
refraction (independently by L. Lorentz) was pub- 
lished in 1878, and he has been an active and fruit- 
ful investigator ever since. 
A Royal Medal is awarded to Professor Alfred 
Fowler. Professor Fowler’s investigations have 
been, in the main, on spectroscopy, and one of his 
specialties has been the identification and reproduc- 
tion of celestial spectra in the laboratory. His ex- 
traordinary success in identification of this kind is 
attributable in part no doubt to a special intuition, 
but. also to a great and laboriously acquired knowl- 
edge of detail. For instance the origin of the 
bands dominating the spectra of stars of Secchi’s 
third class remained a mystery for many years. 
Fowler showed that they were due to titanium 
oxide. He accounted for many of the band-lines 
in the sun-spot. spectrum by showing that they be- 
longed to ‘‘magnesium hydride,’’ and several other 
instances of scarcely less importance might readily 
be given. Another important branch of his work 
is connected with spectrum series. The lines of 
many elements which appear in the are spectrum 
have long been classified into series, and empirical 
relations have been obtained between the position 
of a line in the series and its frequency of oscilla- 
tion. ‘Those lines which are characteristic of the 
spark, and require higher stimulation, were not in- 
eluded in the scheme. Fowler was the first to show 
that the spark-lines form series at all. For this 
purpose he had first to work out experimentally the 
conditions for obtaining an adequate number of 
SCIENCE 
[N. S. Von, XLVIII. No. 1252 
lines belonging to these series. Helium and mag- 
nesium were the elements chiefly studied. It was 
found that the spark-line series could be repre- 
sented by formule similar to those which hold good 
for the are lines, but with a fourfold value of the 
universal constant holding for the are-line series 
of all the elements. 
Apart from these investigations, leading to re- 
sults so simple and definite, there is much deserip- 
tive work on spectra standing to the credit of Pro- 
fessor Fowler and his pupils, which is highly ap- 
preciated by specialists for its accuracy and tech- 
nical value. 
A Royal Medal is awarded to Professor Fred- 
erick Gowland Hopkins. Professor Hopkins was 
among the very earliest, if not actually the earliest, 
$0 recognize and announce that minute quantities 
of certain bodies, the nutritive value of which had 
hitherto been unsuspected, exert an enlormous in- 
fluence upon growth and upon normal adult nutri- 
tion. He showed that without these accessory fac- 
tors—vitamines—a diet otherwise full and seem- 
ingly complete is incapable of allowing growth, 
and even of maintaining body-weight or life. He 
has also made important researches into what may 
be styled the determination of the specific nutri- 
tive values of individual main components of the 
protein molecule; he has, for example, shown that 
when, from a certain diet which was proved to 
maintain nutrition satisfactorily, the two amino- 
acids, arginine and histidine, were together re- 
moved, the diet, though amply sufficient in energy 
and fully assimilable, failed to maintain life. 
More recently Hopkins has attacked the question 
whether an animal’s life can be maintained under 
the condition that, in place of protein or of the 
entire set of amino-acids constituting protein, a 
limited few of the several representative types of 
these constituents are provided in the diet. He 
shows that when, instead of the eighteen different 
amino-acids composing the protein, five only are 
administered, death rapidly ensues if those five be 
selected from the simpler aliphatic components, 
e. g., lucine, valine, alanine, glycine and glutamic 
acid, but that, on the other hand, nutrition and 
life are satisfactorily maintained, at least for a 
considerable period, if the five amino-acids given 
be chosen from the more complex types, such as 
tyrosine, tryptophane, histidine, lysine and cystine, 
which experiment has shown to lie outside the 
range of the synthetic power of the animal body. 
The Rumford Medal is awarded to Dr. A. Perot 
and Professor Charles Fabry. MM. Perot and 
Fabry have introduced a new method of measuring 
