376 Mr. C. Tomlinson on the Motions of Camphor 



latter so as to form a very acute angle with the blade. The 

 " ligament " will then be observed to fall from the point per- 

 pendicularly to the apparent edge of the knife. If the point of 

 the pin be now slipped down behind the knife, the acute angle 

 will appear to be partly filled up ; and on moving the pin so as 

 gradually to increase the angle (pivoting the pin round its point 

 which is held below the edge), it will seem as if connected with 

 the blade by a glutinous substance. 



XLVIII. On the Motions of Camphor and of certain Liquids on 

 the Surface of Water, By Charles Tomlinson, F.R.8* 



1. f\N a former occasion I contributed to this Magazine two 

 V-/ papers on the Motions of Camphor and of certain 

 Liquids on the Surface of Water 1 . These papers contain a large 

 number of references to phenomena which during nearly two 

 centuries have cropped up in the Transactions and Proceedings of 

 various scientific societies at home and abroad, and in many of the 

 foreign and domestic journals devoted to science. Having studied 

 these varied phenomena during a number of years and published 

 many papers thereon, it was with sincere pleasure that I recog- 

 nized in the same field of research a fellow-labourer who, armed 

 with a new theoretical instrument, succeeded in gathering in the 

 abundant crop which had been so widely scattered during so long 

 a period. 



By means of the principle of the surface-tension of liquids, 

 Professor G. Van der Mensbrugghe, of the University of Ghent, 

 has not only succeeded in binding together a magnificent sheaf 

 of facts, but in doing so has contributed to the bundle a number 

 of full and ripe ears of his own growing 2 . 



I must also take this opportunity of thanking him for the 

 very kind terms in which he refers to my labours 3 . 



* Communicated by the Author. 



1 Phil. Mag. for December 1869 and January 1870. 



2 I must also associate with Professor Van der Mensbrugghe's name that 

 of Professor Carlo Marangoni, of the R. Lieeo Dante of Florence. In 1 865 

 he published a pamphlet, SulV espansione delle goccie d'un liquido galleg- 

 gianti sulla superficie di altro liquido, in which he adopts the principle of 

 surface-tension in studying the conditions under which a drop of one liquid 

 spreads upon the surface of another. 



3 " M. Tomlinson avait etudie depuis plus de dix ans le phenomene de 

 l'extension des huiles etles mouvements de certains corps solides sur l'eau ; 

 aussi je n'hesite pas a voir en lui le physicien qui a le mieux prepare la 

 vraie theorie de ces phenomenes, grace aux soins scrupuleux avec lesquels 

 il a decrit les faits, en meme temps qu'au nombre et a la variete de ses ex- 

 periences ; je me plais a ajouter que la lecture de ses travaux a le plus 

 contribues a me suggerer les idees developpees dans mon premier memoire." 



