6?8 



No exact quantitative analyses were attempted by the author, 

 the comparative experiments having been performed on small por- 

 tions only of serum (from 25 to 40 grains) ; sufficiently large, how- 

 ever, to furnish satisfactory evidence of the actual presence of the 

 phosphate in arterial blood, and also in those portions of venous 

 blood which had been arterialized out of the body ; while no such 

 indications were obtained from similar portions of the blood con- 

 tained in the veins. 



At the conclusion of the paper, the author notices the experi- 

 ments of Enderlin, in which no alkaline carbonate could be de- 

 tected in the ashes of blood ; and shows that this is the natural con- 

 sequence of the phosphates of the clot being oxidized during com- 

 bustion, and thus supplying a quantity of phosphoric acid sufficient 

 to decompose completely the alkaline carbonate produced by the 

 incineration of the lactate and albuminate of the serum. Most 

 specimens of serum, even as obtained from arterial blood, yield an 

 alkaline carbonate when incinerated ; and this is always the case 

 with the serum of venous blood. The author, therefore, thinks 

 himself warranted in regarding the conclusion founded on Ender^ 

 lin's experiments, that the blood contains no lactate, as being erro- 

 neous. 



June 17j 1847. 



The MARQUIS OF NORTHAMPTON, President, in the Chair. 



1. "Electro-Physiological Researches, 5th, 6th, and 7th Series." 

 By Signor Carlo Matteucci, Professor in the University of Pisa* 

 Communicated by Michael Faraday, Esq., D.C.L., F.R.S., &c. 



The fifth series of these researches contains the sequel of the 

 author's investigations of induced contractions, which, in his third 

 memoir, published in the Philosophical Transactions for 1845, he 

 had considered as being due to nervous influence acting through 

 the muscles during their contraction, and was therefore referable to 

 a kind of nervous induction, and not to the generation of any elec- 

 tric current by muscular contraction. From the experiment-s re- 

 lated in the present paper, he is led to the conclusion that the phe- 

 nomena of induced contraction belong exclusively to the muscle in 

 the state of contraction. He nov/, however, finds reason for doubt- 

 ing that the fact is established that induced contractions are not 

 due to an electric discharge produced daring the contraction of the 

 muscle. 



The second section of this memoir relates to the phenomena eli- 

 cited by the passage of the electric current through the nerves of a 

 living animal, or of one recently killed, according to the direction 

 of the current. He finds that in whatever manner the current pass- 

 ing through the nerve of the inverse limb is arrested, tetanic con- 

 traction is excited. In order to produce this effect, it is sufficient 

 to moisten the nerve with a large drop of water, or to double it 



