CHAP. XII.] CORRESPONDENCE. 385 



a formal speech, on your legs ; and during its whole con- 

 tinuance it reduces the Society to the form of a closed curve, 

 the elements of which are incapable of changing their relative 

 position. 



For the evolution of science by societies the main re- 

 quisite is the perfect freedom of communication between each 

 member and any one of the others who may act as a reagent. 



The gaseous condition is exemplified in the soiree, where 

 the members rush about confusedly, and the only communi- 

 cation is during a collision, which in some instances may be 

 prolonged by button-holing. 



The opposite condition, the crystalline, is shown in the 

 lecture, where the members sit in rows, while science flows 

 in an uninterrupted stream from a source which we take as 

 the origin. This is radiation of science. 



Conduction takes place along the series of members 

 seated round a dinner table, and fixed there for several hours, 

 with flowers in the middle to prevent any cross currents. 



The condition most favourable to life is an intermediate 

 plastic or colloidal condition, where the order of business is 

 (1) Greetings and confused talk; (2) A short communica- 

 tion from one who has something to say and to show ; (3) 

 Remarks on the communication addressed to the Chair, in- 

 troducing matters irrelevant to the communication but 

 interesting to the members ; (4) This lets each member see 

 who is interested in his special hobby, and who is likely to 

 help him ; and leads to (5) Confused conversation and 

 examination of objects on the table. 



I have not indicated how this programme is to be com- 

 bined with eating. It is more easily carried out in a small 

 town than in London, and more easily in Faraday's young 

 days (see his life by B. Jones) than now. It might answer 

 in some London district where there happen to be several 

 clubbable senior men who could attract the juniors from a 

 distance. 



To PROFESSOR LEWIS CAMPBELL. 



Glenlair, Dalbeattie, 3d April 1873. 



The roof of the Devonshire Laboratory is being put on, 

 2 c 



