118 SIR WILLIAM RAMSAY 



English at that time was imperfect and explosive, and his wit 

 and humour played over the whole proceedings. I wish I could 

 do more justice to him and to the occasion. I believe it effected 

 a good deal towards forming friendships, promoting good will 

 and removing misunderstandings, and certainly it was the begin- 

 ning of relations of great mutual sympathy and regard between 

 Ramsay and Ostwald, which lasted till they were divided by 

 their respective national sympathies at the unhappy outbreak 

 of war." 



So long as nearly forty years ago the subject of 

 Brownian or pedetic motion attracted Ramsay's notice, 

 and in 1882 he communicated to the Bristol Society of 

 Naturalists a short paper on the subject. This curious 

 phenomenon was first described by the botanist Robert 

 Brown (b. 1773 d. 1858) in the course of his observa- 

 tions on the pollen of plants and was at first attributed 

 to life in the moving mass. When a muddy solution 

 or an emulsion like milk is examined under the micro- 

 scope the suspended particles, if small enough, are seen 

 to be in motion constantly but irregularly both as to 

 direction and speed. The motion is not related to the 

 composition of the particles, but only to their size and 

 specific gravity and the nature of the liquid. The 

 motion cannot be attributed to currents in the liquid, 

 for no two particles move in the same direction or with 

 the same velocity. In 1892 Ramsay brought the sub- 

 ject before the Chemical Society. By this time some 

 important experimental work had been done especially 

 by Messrs. Linder and Pic ton at University College, 

 who had shown that they are apparently charged 



