102 Mr. W. D. Halliburton. [June 19, 



which is simplified by introducing H=sin 2 0= , instead of G. We 



_ TT/ _ IT" 2H'* 



in fact have G'=^-, 0"=-^- + -^-, and substituting these 



values, the equation becomes 



'* H" 2H'*\ , 2 ., 8 H' _ 

 + -- + 



viz., this is H"0' + 20' 3 -H'0"=0. 



Writing herein 0+*= ^K ( an arbitrary constant) we have 



and the equation becomes 



TTJE.a-i5!_ *H'K" 



[ +' " ~ 



viz., this is 2(H"K'-H'K")K + (K'-rH')K'2=0, 



which is satisfied by K'-f-H'=0 or K + H=/3, /3 an arbitrary 

 constant. Substituting for K, H their values, this is 



that is, * 2 y3 + (0 2 + cosec 2 ^) + 2*0=0, or, what is the same thing, 

 A+B(0 2 + cosec 2 0) + C0=0, where the ratios A: B : C are arbitrary. 



III. The Proteids of Serum." By W. D. HALLIBURTON, M.B., 

 B.Sc., Sharpey Physiological Scholar. Communicated by 

 Professor SCHAFER, F.R.S. (From the Physiological Labo- 

 ratory, University College, London.) Received May 28, 

 1884. 



(Preliminary Notice.) 



The investigation of which this paper gives a brief summary 

 relates to serum-albumin rather than to serum-globulin, and the 

 experiments may be arranged in two categories : first, those relating 

 to heat-coagulation ; and secondly, those relating to the action of 

 certain salts upon the proteids of blood-serum. 



The apparatus used for the determination of the temperature of the 

 heat-coagulation of proteids was not that which has been usually 

 employed for the purpose, and which consists of two beakers contain- 

 ing water, one within the other, and heated gradually over a sand- 



