SEPTEMBER II, 1902] 
NATURE 
483 
exercised in this College in its earlier years as a skilful pilot 
guiding the ship till it was well out of port. His high ideal of 
the function it should discharge in the education of the country 
and the practical zeal and ability which he ever brought to bear 
on the administration of our affairs contributed in no small 
measure to place the College in the assured position it occupies 
to-day. 
On his great physical and chemical investigations it is happily 
the less necessary for me to touch, as they have been so fully 
brought before you by our President in his opening Address ; 
and as regards the most important of these researches, those on 
the continuity of the Liquid and Gaseous states, no one 
assuredly could have more fitly expounded them than one who 
has himself pressed forward with such splendid success in the 
paths which Andrews opened up. 
I have always considered that Andrews, through the long 
course of these later researches, was most fortunate in having 
near at hand such a friend as James Thomson ; not that he was 
a collaborator—for Andrews did all this work unaided—but 
that Thomson gave him throughout that best of all encourage- 
ment which consists in enlightened appreciation of the import- 
ance of the results he was obtaining and of their inner meaning 
and significance. 
Of Thomson himself what shall I say? Of all the scientific 
men I have come across he perhaps most fulfilled the idea of a 
philosopher, his ever-working brain ever seeking out causes, 
ever pondering on the why and the wherefore of the unex- 
plained. 
One of his earliest investigations is perhaps the best known, 
that in which, basing his reasoning on Carnot’s principle, he 
demonstrates the effect of pressure in lowering the freezing- 
point of water, and in which he gave at the same time a 
numerical estimate to this effect. 
This discovery was of great practical import, for, small as the 
effect was, it enabled him to explain fully the rationale of the 
plasticity of ice. 
Forbes had already shown that the motion of glaciers de- 
pended upon a plastic or viscous quality in the ice. It remained 
for Thomson, by the aid of his newly discovered principle, to go 
a step further and account for this plasticity. 
It is interesting to note that the questions which led to some 
of his most valuable investigations seem to have been started by 
the filial task he took upon himself of re-editing his father’s 
educational text-books. It was, for example, the revision of a 
chapter in his father’s Geography which I believe led him to 
examine more thoroughly into Hadley’s theory of the Trade 
winds, and to make the following important addition to that 
theory. He showed that while in the tropical latitudes, say of 
our northern hemisphere, two currents would satisfy all the 
conditions, z.¢., the Trade wind blowing from N.E. to S.W. in 
the lower regions of the atmosphere, and the return current in 
the upper regions, on the other hand that in the temperate 
latitudes there must be three currents at different elevations ; 
that the uppermost and the lowest of these have a movement 
towards the Pole, but in the middle regions of the atmosphere 
between these there must be a large return current from the 
Pole, and that the prevailing motions of all three currents would 
be from west to east. 
Thomson was particularly successful in his treatment of this 
and other questions of fluid motion. He was not familiar with 
the technique of the higher mathematics, and on this very 
account was not tempted, as sO many mathematical experts are, 
to assume impossible conditions in order to bring the problems 
within reach of their algebraic analysis; but for all that his 
mind was eminently of a mathematical cast. He is never vague 
or loose in his reasoning, and he had a wonderfully tenacious 
grasp of physical principles. The result was that he has suc- 
ceeded in finding out the key to some of the most curious 
phenomena in the motions of fluids. 
I may give as a typical instance of his line of reasoning his 
beautiful explanation of the action of the water of a river flow- 
ing round a bend. He saw clearly that from true ‘dynamical 
principles the flow of the water must be most rapid near the 
inner bank, and the question which presented itself to his mind 
was why then the inner bank was not worn away. The answer 
he showed to consist in the friction of the bed checking the 
velocity of the lowest stratum of the water. The effect of this 
he proves to be that an under-current is produced in this stratum 
across the bed of the river from the outer towards the inner 
bank, a current which does two things: it carries sand and 
NO. 1715, VOL. 66] 
detritus and deposits then on the inner bank; and, since the 
water in this current has to rise vertically to the surface when it 
reaches this bank, it thus protects it from the scour. 
In a review of Thomson’s work we should emphasise his con- 
stant endeavour, whether in Mathematics or Physics, to attain 
clear conceptions of fundamental principles. This showed 
itself in the various innovations in nomenclature he introduced. 
Many of the new words he coined, ‘‘ radian,” ‘‘ numeric,” 
“‘torque,” ‘‘interface,” ‘‘clinure,’’ ‘* posure,” &c., are great 
helps both in thinking and teaching. 
The same determination at any cost of hard thinking to arrive 
at clearness in regard to fundamental principles is strikingly evi- 
denced by one of his later papers, that on the ‘‘ Law of Inertia 
and the Principle of Chronometry,” which is a most searching 
discussion of the true significance of Newton’s first and second 
laws of motion. 
I must now close this review. I shall be glad if I have 
succeeded, however imperfectly, in giving you some impression 
of our Irish schools of Mathematics and Physics, of the workers 
and of the sources from which they drew their inspiration. 
There surely never was a time when the problems presented to 
the mathematician by Physical Science were more interesting ; 
never a time when Science for its onward progress stood more 
in need of those gifted ones who combine clearness of thought 
with imagination and hopeful courage. Let us hope that 
amongst these in this new century, others of our countrymen 
may be found not unworthy to have their names inscribed in the 
roll which contains those of Hamilton and MacCullagh, of 
Andrews and Thomson. 
NOTES. 
WE record, with very deep regret, the death of Prof. 
Virchow, on September 5, in his eighty-first year. The 
State funeral accorded to Prof. Virchow took place in 
Berlin on Tuesday. Among those present were the Prussian 
Ministers of Education and Finance, the Foreign Secretary, the 
Chief Burgomaster of Berlin, and numerous representatives 
of Berlin and other universities, and of learned and scientific 
societies—both German and foreign. After the funeral service, 
orations were delivered, in which Prof. Virchow was considered 
as man of science, politician and municipal reformer. At the 
meeting of the Paris Academy of Sciences on Monday, a eulogy 
on Prof. Virchow was delivered by M. Bouchard. 
WE have also to announce the death of Sir Frederic Abel, on 
September 6, in his seventy-sixth year. 
THE next meeting of the Australasian Association is to be held 
in Dunedin, New Zealand, in January, 1904, and the following 
have been appointed presidents of sections :—B—Chemistry : 
J. Brownlie Henderson, Brisbane. C—Geology and mineralogy : 
W. H. Twelvetrees, Hobart. D—Biology: Colonel W. V. 
Legge, R.A., Hobart. E—Geography: Prof. J. W. Gregory, 
Melbourne. F—Anthropology and philology: A. W. Howitt, 
Melbourne. G—Economics, subsection 2, agriculture: J. D. 
Towar, Roseworthy, South Australia. H—Architecture, en- 
gineering and mining: H. Deane, Sydney. I—Sanitary 
science and hygiene: Dr. Frank Tidswell, Sydney. J—Mental 
science and education: John Shirley, Brisbane. 
THE annual congress of the Sanitary Institute was opened at 
Manchester on Tuesday last, when some two thousand delegates 
were present from all parts of the country. 
IN connection with the celebration of the 1ooth anniversary 
of the birth of Niels Henrik Abel, now in progress at Christiania, 
twenty-nine foreign men of science on Saturday last received the 
degree of Doctor, Hov072s Causa ; among the number were Lord 
Kelvin, Lord Rayleigh, Sir George Stokes, Prof. G. H. Darwin, 
Prof. Forsyth, and the Rev. George Salmon, Provost of Trinity 
College, Dublin. 
Tue Punjab Government has, according to the special Indian 
correspondents of the Zancet and the British Medical Journal, 
