190 SECONDARY ELECTROMOTIVE PHENOMENA IN 



the curves should have been drawn from the (A) axis beyond 

 the ^-axis. This was the less worth while that it is now apparent 

 that such a double figure would be necessary for each half of the 

 muscle. 



Polarisation experiments, with cross direction of the primary 

 current in muscle, are made with great difficulty, and have not yet 

 been satisfactorily carried out. 



11. On the Influence of various circumstances on the 

 Polarisation of Muscles. 



The fact chiefly to be insisted upon is that internal positive 

 polarisation of muscles is only found in the living condition. 



I had formerly stated that internal negative polarisation still 

 existed in boiled muscles l . This was an error of which I became 

 conscious afterwards, when I experimented on single muscles instead 

 of entire limbs. The internal polarisability of frog's muscle is 

 destroyed by scalding, and completely annulled by boiling. 

 Nevertheless, strong internal negative polarisation is found in an 

 entire boiled frog's leg as I had already rightly observed. On closer 

 investigation, however, it was seen that while the muscle itself was 

 entirely inactive, this polarisation had its seat in the knee joint, 

 that is in the bones or ligaments, or both. The ankle joint of a 

 boiled leg was also found to be strongly polarisable. In the case 

 of the entire limb, the muscles of the limb serve only as conductors 

 to the joint. 



Muscles which have been killed in other ways, beef from the 

 butcher, frog's muscles which have lain forty-eight hours in a moist 

 chamber, or in water, or which have been dried over chloride of 

 calcium and then been softened again only indicate on the galva- 

 nometer slight traces of internal negative polarisability with a 

 current of fifty Groves. 



Scalding and boiling therefore exercise a remarkably destructive 

 influence on internal polarisability of the muscles. At the same 

 time, I found in September, 1855, that boiling materially lessened 

 the peculiar resistance of the muscle, which fact has been thoroughly 

 investigated since by Joh. Kanke 2 . Whether this fact and the 

 destruction of internal polarisability of muscles by boiling are con- 

 nected with each other we shall see further on (Sect. 21). 



I think I have remarked that the long continued passage of a 



1 Untersuchungen liber thierische Elektricitat, vol. i. pp. 378, 379. 



3 Joh. Ranke, Tetanus. Eine phyeiologische Studie, Leipzig, 1865, pp. 10, 19 ff. 



