Mr. G. O. Rees on theTresence of Titanium in the Blood, 20 f 



Or, l+r^%l^-^+ r("-')'" 



1+^2' +,.2-2; /«.-i)2' 



X 



{i-/->"- .C"-)^"-'} 



to p — q factors of wz terms each. 



8. From this it appears that if an odd number of terms of a 

 geometric series be separately raised to the power of 2^', and 

 divided by the same terms raised to the power of 2^, the quo- 

 tient will consist of p — q factors, each of which is a geometric 

 series of the same number of terms as the original one, with 

 the signs of the even terms negative. 



[To be continued.] 



XXXIV. On the Presence of Titanic Acid in the Blood, By 

 Mr. G. O. Rees. 



To Richard Phillips, Esq., F.R.S., ^c. 

 Sir, 

 XrOU will much oblige me by inserting the following ex- 

 -*- periments in the London and Edinburgh Philosophical 

 Magazine and Journal of Science. 



Your obedient Servant, 



G. O. Rees. 

 While making some further observations on the presence 

 of titanium in organic matter, I was induced to examine the 

 blood, in order to assure myself that its existence in that fluid 

 had not been overlooked. For that purpose the following 

 experiments were made. A portion of incinerated blood was 

 digested in strong nitro-muriatic acid at a boiling tempera- 

 ture: the solution so formed was decanted from the insoluble 

 residue, which consisted of granular white particles in admix- 

 ture with a portion of carbon thiit had escaped dissipation. 

 The decanted solution was evaporated to dryness. Very dilute 

 sulphuric acid was next boiled on the dry mass for a few mi- 

 nutes, when a considerable quantity of a fawn-coloured powder 

 was observable at the bottom of the vessel : this powder was 

 Third Series. Vol. 6. No. 33. March 1835. 2 D 



