THE CHANGE IN FORM 361 



In tetanus no weight is raised and no visible 

 mechanical work is performed. That internal 

 work is performed is shown by the rise in 

 temperature. 



Time Relations of Developing Energy. The 

 simple muscle curve is a graphic record of the 

 mechanical energy set free by the muscle in lift- 

 ing a certain load. It is desirable to measure the 

 maximum energy that the muscle can set free at 

 each moment from the beginning of contraction 

 to the point at which the greatest shortening is 

 reached. 



Place the electromagnetic signal in the primary 

 circuit of an inductorium arranged for maximal 

 make induction currents. Arrange a tuning fork 

 to write on a smoked drum beneath the line 

 drawn by the writing point of the signal. Fasten 

 the femur of a gastrocnemius muscle in the 

 muscle clamp and attach the tendon to the heavy 

 muscle lever. Place the three writing points in 

 the same vertical line. Connect the binding posts 

 on the muscle clamp and the lever with the posts 

 of the secondary coil of the inductorium. " After- 

 load " the muscle with 50 grams. Set the tuning 

 fork vibrating. Spin the drum. Stimulate the 

 muscle with a single maximal make induction 

 current. 



The muscle will not shorten until the energy 



