316 Mr. J. S. Mu.-dniuM. 



(n) weight. 



An increase of < <*> 



(c) rigidity. 



(</) elasticity. 



I (b) conductivity. 



Thus a piece of sciatic nerve (cat) examined before and after an 

 mersion of 20 minutes in tap water : 



Before. After. 



Weight in grammes 0'237 0*317 



Length in centimetres 4'8 5-4 



Resistance in ohms 14,200 18,400 



The general condition is known, and has been previously described 

 as " water rigor " ; a similar change produced by the action of water 

 upon muscle has been found (see Fletcher*) to be unattended by the 

 chemical changes accompanying other forms of rigor. 



With the exception of the change in conductivity, all the changes 

 are rapidly developed, reaching their maxima within an hour after 

 immersion in water they may remain for days in an approximately 

 maximal condition, but are at any time abolished by a short immersion 

 in 0'9 per cent. " saline." The change in conductivity is a much more 

 gradual one, as is well shown by the details of an experiment. In 

 the following experiment the appearances of rigor were fully de- 

 veloped within the first hour, the available E.M.F. had also risen to its 

 maximum (0*027 volt as contrasted with the initial value 0*018 volt), 

 whereas the nerve still retained 70 per cent, of its original con- 

 ductivity. 



Experiment. Sciatic Neme of Dog. 



Length of piece used, 5 cm. 



The initial resistance having been measured, the nerve was placed in 

 tap water (1 litre) from which it was removed every twenty-five 

 minutes for re-examination. 



* ' Journal of Physiology,' vol. 23, i, ii, 85. 



