90 LOCALIZED ELECTRIZATION. 



^ I[_ — Electrization of the shin hy dynamic eJedricity ; or cutaneous 



galvanization. 



I have already said that cutaneous excitation by dynamic 

 electricity is practised by dry rheophores, "applied to the dry skin, 

 and that the resulting sensation ranges from simple tingling to 

 acute pain. It is well known that galvanism does not act upon 

 the skin without causing an alteration more or less considerable 

 (vesication or cauterisation) ; while faradism produces no greater 

 orcranic change than little papules or erythema. It follows that 

 cutaneous galvanization should only be applied in certain cases ; 

 and that cutaneous faradization, which respects the tissues, is one of 

 the most valuable and most frequently indicated tlierapeutic agents. 



§ III. — Electrization of the shin hy the induced current; or cutaneous 



faradization. 



These reasons have determined me 'to treat specially of cutaneous 

 faradization ; the methods of applying which are the same as for 

 cutaneous galvanization. 



I. IMODE OF OPERATING. 



The different electro-cutaneous excitability of different regions 

 of the body requires the use of different methods of cutaneous 

 ftiradizatiou. The procedures are of three kimls : faradization by 

 the electric hand, by solid metallic rheophores, and by electric 

 threads. 



Each of these methods possesses a special action, which may be 

 rendered available in therapeutics ; and I proceed to describe their 

 application. 



A. — Tlie electric hand. 



In this method a moist rheophore is used (a sponge contained in 

 a cylinder) like that shown in fig. 25. This is put into communi- 

 cation Avith one pole of the apparatus, and is then applied to some 

 insensitive part of the patient's body. The other rheophore, in 

 communication with the other pole, is held by the operator, wlio, 

 having first dried the skin to be faradized by some absorbent 

 powder (lycopodium or rice starch), passes the back of his free 

 hand, also dried, over the points which he wishes to excite. 



B. — Solid metallic rheophores. 



The skin must be dried as above described ; although if the 

 epidermis be very thick and hard, as it becomes from some occu- 

 pations, and chiefly on the hands and feet, which are often in more 



