OBITUARY NOTICES. xV 
proved.’’ Stokes may justly be looked upon as in a sense one of 
the intellectual parents of the school of Natural Philosophy which 
Cambridge has nurtured, the school which numbers in its ranks Sir 
William Thompson and Sir William Maxwell. 
He was really a great discoverer in Mathematics and Physics. 
Stokes fully apprehended the physical basis of spectral analysis and 
pointed out how it could be applied to the detection of the con- 
stituents of the atmosphere of the sun and stars. In some of his 
earlier papers he has laid down the scientific distinction between 
rotational and differentially irrotational motion, which forms the 
basis of Helmholtz’s magnificent investigations about vortex mo- 
tion. His papers on the (long) spectrum of the electric light, and 
particularly those on the absorbent spectrum of the blood, are of 
very great value. 
Sir William Thompson says that Stokes roamed over the whole 
domain of Natural Philosophy in his work and thought, Electricity 
being the single field which he looked upon from the outside. He 
even enriched pure Mathematics of a highly transcendental kind. 
Mathematics with Stokes was the servant and assistant, not the 
master. In science his guiding star was Natural Philosophy. In 
1843 he published his Zheory of the Viscosity of Fluids and a little 
later his Zheory of Oscillatory Waves. ‘*The Dynamical Theory 
of Diffraction’’ was one of his most important contributions on the 
subject of light. In his paper on ‘‘ The Change of Refrangibility 
of Light’’ he described his now well-known discovery of Fluor- 
escence, according to which a fluorescent substance emits in all 
directions from the course through it of a beam of homogeneous 
light. 
Stokes’ scientific work and scientific thought are but partially 
represented by his public writings. He gave generously and freely 
of his treasures to all who were fortunate enough to have the oppor- 
tunity of receiving from him. 
Sir William Thompson says ‘‘that his teaching me the principles 
of solar and stellar Astronomy while we were walking about among 
the Colleges, sometime prior to 1852, is but one example of his gen- 
erosity.” 
The funeral of this great man took place last February at Cam- 
bridge, England. The most distinguished representatives of many 
branches of learning were present. The University church was 
crowded in every part. The assembly constituted a living witness 
