332 THE OUTGO OF ENERGY 



bubbles shall be excluded. If the height of the 

 water-column in the capillary tube 



A does not permit the meniscus to be 



readily observed, move the glass rod 

 in the stopper in or out until the 

 meniscus is adjusted. Connect the 

 electrodes with the secondary coil 

 of an inductorium arranged for 

 single induction currents. Note 

 carefully the level of the water in 

 the capillary tube. Stimulate the 

 muscle with a maximal break 

 current. 



ss. The The level of the water in the 



v "" u " etnl)e - capillary will not change. The 

 change in the 1'orm of the contracting muscle 

 is not accompanied by a change in volume. 1 



THE SINGLE CONTRACTION OR TWITCH 



The change in the form of the muscle on 

 entering the active state is usually studied from 

 the graphic record made on a smoked surface 

 by a writing lever the shorter arm of which is 

 attached to the end of the muscle. Such a 

 record, it should be remarked, gives the extent 



1 This experiment must not be regarded as excluding a very 

 slight change in volume, because of the difficulty of expelling, 

 by boiling or otherwise, all the air in the saline solution. 



