94 



On the Mathematical Theory of Combined Streams. [Nov. 17, 



factor of resistance, F, is given, into a reservoir in which the pressure P 

 and the elevation Z of the surface above the junction-chamber are given. 

 These, together with the areas A, a v a 2 , &c, are the quantities given. 

 The functional values given are those of the bulkiness, * oJl , s , 2 , &c, and S , 

 as before ; also the following values of the velocities, according to well- 

 known principles in hydrodynamics ; for any component stream, 



The functional values given are to be substituted in equations (1) and 

 (2), whose solution will then give the numerical values of p Q and P ; and 

 from these and the other data the numerical values of v l &c. and of Y 

 may be calculated. 



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. 



General Boileau, Mr. Busk, Mr. David Forbes, Sir John Lubbock, and 

 Mr. Mivart, having been nominated by the President, were elected by 

 ballot Auditors of the Treasurer's accounts on the part of the Society. 



Mr. Andrew Noble, Capt. Sherard Osborn, and Mr. George Frederic 

 Verdon were admitted into the Society. 



Anders Jons Angstrom, of Upsala, and Joseph Antoine Ferdinand 

 Plateau, of Ghent, were proposed for election as Foreign Members, and 

 notice was given from the Chair that these gentlemen would be ballotted 

 for at the next Meeting. 



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

 them. 



The following communications were read : — 



I. " Researches into the Chemical Constitution of the Opium Bases. 

 — Part IV. On the Action of Chloride of Zinc on Codeia." By 

 Augustus Matthiessen, F.R.S., Lecturer on Chemistry at St. 

 Bartholomew's Hospital, and W. Burnside, of Christ's Hos- 

 pital. Received June 23, 1870. (See page 71.) 



and for the resultant stream, 



November 17, 1870. 



