310 Mr. J. A. Mac William. The Mechanism and 



In the case of a heart which is showing individual fibrillar beats of the 

 nature already described the process of recovery i;nder the influence of 



B. 



Fig. 8. — R.V. recorded. Fibrillation from application of faradic current (200 units). 

 A is taken 7 seconds after beginning of fibrillation. B shows recovery occurring 

 after fibrillation had lasted 75 seeonds, massage being done at intervals. Adrenaline, 

 0'27 mgrm., had been injected previously, and this probably favoured recovery. 

 Marked coarsening of the movement (followed by a long pause) is seen prior to 

 recovery. 



massage, removal of depressing influences, etc., is usually a more elaborate one. 

 The phase of slow coarse fibrillation has to be passed through, with a gradual 

 increase in the rate and the grade of dissociation as excitability is restored ; 

 this leads up to the condition of rapid fine fibrillation — from which recovery 

 occurs in the fashion stated above. But treatment with certain doses of 

 adrenaline, etc., may sometimes change the fibrillar beats into co-ordinated 

 ones without a transition through the various phases just enumerated (fig. 9). 



A. B. 



Fig. 9. — A shows slow coarse fibrillation — a series of irregular fibrillar beats. B is 

 taken shortly after the injection of 0'2 mgrm. adrenalin into the L.V.[(1 in 5000 

 solution used). The fibrillar beats are changed into normal ones. 



