ANALOGY OF THE ELECTRO-MAGNET. 145 



the arguments of Beale are most cogent which rest on 

 the totally different character of the movements, which 

 need not be gone over again. So there seems to 

 remain nothing but the theory of a current force of the 

 nature of electricity, which may be supposed to change 

 the shape of the flesh-prisms by altering the position 

 of the disdiaklasts, or to change the position of the 

 sarcous particles as a whole, and to increase the 

 cohesion of the particles of the fibre as a whole, pro- 

 bably by some change similar to that which iron 

 undergoes when magnetized. This we know becomes 

 lengthened in the direction of magnetization owing, as 

 supposed by De la Rive, to the crystals of which the 

 solid bar is composed setting themselves parallel to the 

 bar in their longest dimensions. Even when the mag- 

 netic oxide of iron is reduced to fine powder and 

 suspended in water, in a vessel surrounded with a coil 

 forming part of a voltaic circuit, the same tendency is 

 shown and the particles attach themselves in lines 

 (Grove). If we suppose the action of the nerve current 

 to be the reverse here or diamagnetic as it were, we 

 have a dim representation of the action of the striped 

 and smooth muscular fibres. There is also a clink 

 heard when the circuit is made and broken in the 

 electro-magnet, and this is paralleled by the muscle- 

 sound. 



The question, as placed by Dr. Beale, is entirely 

 different from the position which the electric theory 

 has ever occupied before, for now it is not the question 

 of a mere stimulus given by the motor nerves, but the 

 whole force needful for the work must be furnished by 

 them, and as this is a measurable quantitative relation, 



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