PROFESSOR W. C. ROBERTS-AUSTEN ON THE DIFFUSION OF METALS. 415 
The founder of this lectureship directed in 1768 that the subject be selected from 
“ Such part of Natural History or Experimental Philosophy as the Council of the 
Royal Society shall be pleased to appoint,” and in the century which followed the 
date of Mr. Baker’s bequest, these branches of knowledge seemed to diverge widely. 
The investigation and measurement of molecular movement has, however, gradually 
joined them in the closer union which Graham did so much to effect. His work in 
experimental physics, more than that of any other investigator, taught the 
physiologist that tracing the relations of the phenomena of life as revealed in diffu¬ 
sion, transpiration, and osmosis will afford Natural History its most precious records. 
The evidence gathered by the metallurgist of active atomic movement in fluid and 
solid metals may sustain the hope of the physiologist that he will ultimately be able 
to measure the atomic movements upon which vitality and thought depend. 
