CONTEACTION UNDER GALVANISM. 141 



which is always irregular, and composed of separate longer or 

 shorter contractions. Can it be, therefore, that the galvanic 

 current conducted by the sarcolemma, or connective tissue, 

 may furnish the force inductively to cause the physical change 

 in which contraction consists, just as the nerve force does 

 naturally 1 ? We should thus have contraction without vital 

 action or irritability. I cannot find that this observation has 

 been confirmed, and especially if the work done has been 

 measured. Wundt further asserts that the contractile substance 

 itself will not contract under anything else but the galvanic 

 current. Schiff and Eckhard, however, deny that the current 

 can act at all upon it except through the nerves, while Kiihne 

 reiterates his assertion of the action of both galvanism and 

 chemical stimuli, in spite of these three. Kiihne ultimately, 

 by using very fine electrodes, finds several points in the muscle, 

 even in the centre close under the nerve trunk, where the irri- 

 tability is at a minimum, just like the extreme ends, and there- 

 fore he concludes that these spots are also destitute "of nerves. 

 Nevertheless, he observes that these points seem to receive a 

 nerve stimulus in some way, because they contract also when 

 the nerve trunk is excited (594). This harmonizes with Beale's 

 view that they are supplied with the fine nerve fibres which 

 must have been reflected from some finer twigs at a distance 

 from the trunk entrance. 



The representation we may keep in mind of the 

 mechanical conditions of muscular fibres in action, is 

 as follows : To form a fibre (or primitive bundle), we 

 have a long, delicate, flexible closed sheath the sarco- 

 lemma in which is contained a semi-fluid, single 

 refracting substance, in which are embedded a number 

 of three to five sided prismatic double-refracting 

 bodies, arranged in the striped muscles, in regular 

 layers (Bowman's discs). During the act of contraction 

 these discs become broader and thinner, and approach 



