189.3.] On the Metallurgy of Bismuth, 467 



action of small doses of strophanthin on the cardiac nervous mecha- 

 nism of that animal. 



The lengthening out of the systole in veratrine poisoning corre- 

 sponds to the same well-known lengthening of the systole in the 

 frog's heart under veratrine. The reversing of rhythm observed in 

 morphine poisoning is similar to that mentioned by Ludwig* as 

 occurring in the mammalian ventricle when under the influence of 

 opium, for then the auricular beats follow instead of precede the 

 ventricular beats, the rhythm being reversed. The same occurs in 

 amyl nitrite poisoning. 



Krukenbergf has stated that neither atropine nor muscarine 

 affects the heart of Ascidians. 



My observations on the action of atropine and muscai'ine, which 

 have been made on a large number of embryos, show that in the 

 absence of a nervous mechanism they do not influence the heart. 

 This will probably modify the current views on the action of these 

 drugs, and my results show that the method I have adopted is a 

 valuable one for differentiating the functions of cardiac muscle from 

 those of the nerves which supply it. 



II. " Further Researches in Connexion with the Metallurgy of 

 Bismuth." By EDWARD MATTHEY, F.S.A., F.C.S., Assoc. 

 Roy. Sch. Mines. Communicated by Sir G. G. STOKES, 

 Bart, F.R.S. Received November 21, 1892. 



In 1886-87 and in 1890 I submitted papers to the Royal Society 

 bringing under notice facts which had come to my knowledge whilst 

 engaged upon the practical extraction of this beautiful metal from its 

 ores, and in its separation from impurities waich are always associated 

 with it when in a crude or unrefined state. 



IV. Bismuth, its Separation from Arsenic. 



In a paper dated February 10, 1887,^ allusion is made to the fact 

 that arsenic is often one of these impurities, and at the same time a 

 method is given by which the separation of this metal from bismuth 

 was then successfully effected. 



The process adopted when that paper was read, and for a consider- 

 able period subsequently, when working upon bismuth containing 

 arsenic, consisted in removing the arsenic by fusing the arsenical 



* Ludwig, 'Lehrbuch der Physiol. des Menschen,' Bd. 2 (1861), p. 38. 

 f Krukenberg, quoted in Brunton's 'Text- Book of Pharmacology,' &c. (3rd 

 edition, p. 114). 



I ' Proc. Boy. Soc.,' vol. 49. 



VOL. LIT. 2 I 



