xl Proceedings. [Afaj^ igth, igoj. 



"sonian Institution in 1882. It is for this masterpiece that, in 

 "this home of John Dalton, the Wilde Medal has been awarded 

 " to I'rofessor Clarke by the Manchester Literary and Philo- 

 " sophical Society, on the appropriate occasion of the Centenary 

 "of the Announcement of the Atomic Theory by John Dalton 

 " before this Society." 



" In dealing with the life-work of Professor Reynolds, the 

 " sympathetic biographer of Joule, it is difficult to know where 

 " to begin and where to end. I can but select a few of his 

 " additions to knowledge which stand out from the rest. 



" The first ten of his papers were communicated to this 

 " Society, beginning with that ' On the Suspension of a Ball by 

 "a Jet of Water,' in 1870. The paper 'On the Destruction of 

 " Sound by Fog,' in 1873, was the first of a series dealing with 

 " the Propagation of Sound in the atmosphere, and constituting 

 " the standard authority in this field of experiment. 



" His hydrodynamic work may be said to have begun in 1873, 

 " when he published his ' Experimental and Theoretical Inves- 

 " ligation on the Causes of the Racing of Screw Steamers,' 

 " read before the Institute of Naval Architects. 



"In 1875, his paper 'On Friction and Lubrication,' read 

 " before the Royal Society, was the beginning of a third series 

 "leading up to that 'On the Theory of Lubrication,' which 

 " shed light on a subject up to that time involved in obscurity. 



" Nor must the fact be omitted that he designed an engine 

 " for experimental purposes in 1889. With this he has determined 

 "the Mechanical Equivalent of Heat, standing in this respect in 

 " the same relation to Joule as Professor Clarke stands to Dalton. 



"In 1879 Professor Reynolds made a fresh departure in his 

 " paper ' On the Dimensional Properties of Matter in the 

 " Gaseous State.' This was followed by ' The Discovery of the 

 " Criterion distinguishing the Continuous from the Discontinuous 

 " Motion of a Fluid,' and later by a third paper ' On the 

 " Dilatancy of Granular Media.' These led to his last great 

 " work, recently published by the Royal Society, ' On the Sub- 

 " Mechanics of the Universe.' We have not yet had time to 



