EXPERIMENTS AVITH SOAP BITBELES.^ 



By C. V. Boys. 



n\'ith i plate.] 



I had a certain feeling of hesitation in suggesting that you wonld 

 ])erhaps bo interested in seeing some experiments which I Jiave 

 devised with soap bubbles. I feared that such a subject woidd liave 

 but slight scientific interest for a learned body like yours. However, 

 your accomplished secretary has assured me that my experiments 

 will be well received, and so I trust that you v/ill l)e indulgent. 



To me a soap bublde is a beautiful thing. It appeals to several 

 senses and to many kinds of minds ; it is a source of dehght to children, 

 and we who know somewhat of the mysteries of molecular physics 

 which it helps to reveaj look at it with admiration. With its aid 

 we are enabled to make clear the action of forces relating to other 

 branches of ])hysical science with greater facility and delicacy often- 

 times than by any other means. I have observed that the soap 

 ])ubble even arouses the curiosity of monkeys, and especially of those 

 whose intellectual development is furthest advanced, viz, the chim- 

 panzee and the orang-outang. In a word, among the objects with 

 which Ave all are familiar and which excite in us a genuine scientific 

 interest the soaj) bubble takers ])receden('e of all others of the same 

 weight. 



Befor(5 I show you any of juy ex])erjincnts, it Avould scmmii to be 

 iucumbent ou me to ])ay the tril)ute of my aduiiration to Plateau, 

 that man of genius who, after being stricken with blindness, obliged 

 to make use of the eyes and hands of his daughter-in-law, contrived 

 and develo])ed experiments and theories relating to the science of 

 (•a])illarity which have compelled the admiration of the scientific 

 world, and Avhose great work, "Statique des Liquides," is a fit numu- 

 ment to the author's genius. When I reflect upon the wealth of 



' Lecture before the Soci6t6 frangaise de Physique, April 12, 1912. Translated by permission from Journal 

 (le Physique, series 5, vol. 2 (August, 1912). See Soap bubbles: Their colours and the force.s which mould 

 them, by C. V. Boys, F. R. S., lOth thousand. Society for Promoting Christian Knowledge, Northumber- 

 land Avenue, Loudon; E. S. Gorham, New York; and Hoys (C.V.), member of the Royal Society: BuUes 

 de Savon, Four lectures upon Capillarity, before a Juvenile Audience. Translated from English by Mr. 

 C. Ed, Guillaume, Sc. D., with new notes by the .•\uihor and the translator, IS ino., («3 figures and 1 plate. 

 Paris, Gauthier \'illars, 1912. 



211 



