104 OF VITAL MOTION. 



move towards each other with increasing velocity, 

 according to a certain and definite law, until they 

 merge into one ; but concede the antagonistic force, 

 and the results of the pure law of attraction are at 

 once masked. That law, therefore, which M. Schwann 

 requires in muscular contraction is impossible, except 

 he could do away with the matter of the muscle, and 

 all opposing force in other quarters. 



Instead of being a valid objection, therefore, the 

 experiment under consideration merely shows that 

 the normal manifestations of the law of attraction in 

 muscles, as in other bodies, is masked by a force of 

 resistance ; and hence the only value of the experi- 

 ment is as a measure of the degree of this resistance. 

 Alter, indeed, the manner in which the facts are 

 stated, and the result is simply this .that a muscle 

 contracts to a certain degree when it has a given 

 weight to raise, to a greater degree when the weight 

 is lessened, and to the greatest degree when the scale 

 is emptied, and when the antagonizing influence is 

 only that which is furnished by the substance of the 

 muscle itself. 



M. Schwann would have had reason for his con- 

 clusions, if he had found the muscle to contract to the 

 same extent in each of these differing circumstances ; 

 but this was not the case, and the amount of shorten- 

 ing was always inversely proportionate to the resist- 

 ance. There is less reason, also, for the arrival at 



