1 66 PHYSIOLOGICAL PHYSICS. [Chap. xv. 



For nutritive purposes also galvanisation is employed 

 in chronic rheumatism. 



As a counter-irritant for rheumatic joints, faradisa- 

 tion by a wire brush over the affected joints has been 

 said to yield good results. 



(2) As a sedative in various forms of neuralgia 

 and headache, electricity is invaluable. According to 

 physiological theory, a weak constant current should 

 be used, and anelectrotonus produced over the 

 painful spot. For headache, one electrode may be on 

 the forehead and the other at the back of the head, 

 or one on one temple, the other on the opposite; 

 Great caution and the use of weak currents are 

 necessary. For ringing in the ears (tinnitus aurium)^ 

 the constant current is of use, one electrode (cathode) 

 at the nape of the neck, and the other in the meatus 

 externus, which should be filled with salt solution. 



As an antispasmodic in wry-neck, writer's cramp, 

 and other forms of spasm, the constant current is 

 applicable. In wry-neck it is applied directly over 

 the affected muscle ; in the writer's cramp Dr. Althaus 

 believes the best results are obtained by applying one 

 pole to the upper vertebrae, and the other over the 

 superior cervical sympathetic ganglion, the seat of 

 disease, according to him, being "in the upper portion 

 of the spinal axis." 



Antispasmodic effects have also been observed in 

 blepharo-spasm and choreaic movements. 



For ovarian pain a constant current may be tried ; 

 the anode over the painful spot, the cathode over some 

 indifferent part. 



(3) Electrolysis. A constant current of electricity 

 decomposes animal tissues as it decomposes water or so- 

 lutions of salts. This property may be made use of for 

 the production of eschars, or for decomposing .tumours, 

 etc. The caustic action of the negative pole is greater 

 than that of the positive. The negative pole, of a size 



