THE 



PROCEEDINGS 



OF 



ROYAL SOCIETY. 



November 16, 1871. 

 General Sir EDWARD SABINE, K.C.B., President, in the Chair. 



In pursuance of the Statutes, notice of the ensuing Anniversary Meeting- 

 was given from the Chair. 



Notice was given that at the next Meeting of the Society, H.M. Pedro 

 II., Emperor of Brazil, would be proposed for election and immediate 

 ballot. 



Dr. Allman, Dr. Blakiston, Mr. Etheridge, Mr. Newmarch, and Dr. 

 Odling, having been nominated by the President, were elected by ballot 

 Auditors of the Treasurer's Accounts on the part of the Society. 



Dr. William Budd, Mr. Carl Schorlemmer, and Mr. Edward Burnet 

 Tylor were admitted into the Society. 



The Presents received were laid on the table, and thanks ordered for 

 them. 



The following communications were read : — 



I. " Considerations on the Abrupt Change at Boiling or Conden- 

 sing in reference to the Continuity of the Fluid State of Matter." 

 By Professor James Thomson, LL.D., Queen's College, Belfast. 

 Communicated by Dr. Andrews. Received July 4, 1871. 



When we find a substance capable of existing in two fluid states different 

 in density and other properties while the temperature and pressure are the 

 same in both, and when we find also that an introduction or abstraction 

 of heat without change of temperature or of pressure will effect the change 

 from the one state to the other, and also find that the change either way 

 is perfectly reversible, we speak of the one state as being an ordinary 



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