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 1 
 
 ELECTRICITY 
 
 'S 
 
 i 
 
 AS APPLIED TO PEAOTIOAL MEDIOIKE 
 
 I 
 
 \ 
 
 BY 
 
 ^ 
 
 I 
 
 I 
 
 I 
 
 ALBERT G. NICHOLLS, M.A„ M.D. 
 
 RESIDENT PHYSICIAN TO 
 
 THir KOTAL YIOTOEIA HOSPITAL 
 
 MONTREAL. 
 
 
 
 
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 4 
 
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 MONTREAL : 
 THE GAZETTE PRINTING COMPANY 
 
 1896. 
 
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ELECTRICITY 
 
 AS APPLIED TO PRACTICAL MEDICmE 
 
 BY 
 
 ALBERT G. NICHOLLS, M.A., M.D. 
 
 RESIDENT PHYSICIAN TO 
 
 THE ROYAL VICTORIA HOSPITAL 
 
 MONTREAL. 
 
 MONTREAL : 
 THE GAZETTE PRINTING COMPANY 
 
 1896, 
 
NOTE. 
 
 This paper was originally read before the members of the 
 McGill University Medical Society, and has been published 
 at their request. A few alterations have been made in its 
 scope, but only such as render it more suitable for production 
 in the present form. A. G. N. 
 
• . ELECTRICITY 
 
 AS APPLIED TO PKAOTIOAL MEDICINE. 
 
 ALBERT G. NICHOLLS, MA., M.D., 
 
 RESIDENT PHYSICIAN TO 
 
 THE ROYAL VICTOR f A HOSPITAL, 
 
 MONTREAL. 
 
 Ever since there was such a thing as the medical art or a 
 knowledge of electricity itself electricity, after some crude 
 fashion, has been employed in therapeutics. With Galvani, 
 who, in 1786, discovered 'animal electricity' and the 
 electrical excitability of nerve and muscle, we emerge from 
 the realms of pure speculation and reach the solid substratum 
 of attested fact. From 1840 to 1843 the subject of animal 
 electricity was investigated by Matteucei and Du Bois- 
 Reymond, followed later by Arsonval who perfected their 
 methods. Remak, in Germany, was about the first to apply 
 electric currents to therapeutics and made use of them with 
 considerable success in the treatment of joint affections, such 
 as sprains, rheumatism, and rheumatoid arthritis. To 
 Duchenne, in France, belongs the ci'edit of applying electricity 
 to the diagnosis and treatment of nervous manifestations such 
 as paralyses, neuralgia, and the various neuroses. 
 
 tJntil very recently, however, the study of electro-thera- 
 peutics has hardly been taken seriously by the medical 
 profession. This is possibly in part due to the inherent difficul- 
 ties connected with the subject. Notwithstanding the fact 
 that electricity is now regarded as one of the greatest 
 civilizers of the age, and notwithstanding the perfection to 
 which electrical appliances have been brought, even yet many 
 of the fundamental questions in the physics of the subject 
 
 i 
 
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 yiyr .wyr^wr^.^i-^ , Vi\.' fr j^7^v'i(%'f 
 
 iiijeiiaiw'^ '<*•'* >j:> 
 
 have nut been solved, and the whole domain of 'animal 
 electricity' and the efteets of electi'icity upon the animal 
 ec<momy is one of the most difficult which we can be called 
 upon to investigate. In this as in many other departments of 
 tiierapeutics empiricism has advanced far beyond scientific 
 kninvlcdge. Not only are there many facts in electro-physiology 
 and in electro-therapeutics yet to be elicited, but the explana- 
 tion of such facts as we do know is often shrouded in mystery. 
 Besides this, the whole suV>ject of electro- therapeutics has un- 
 deservedly been associated with the idea of ([uackery and 
 charlatanism and it has been difficult to induce physicians to 
 enter upon this lield of investigation. 
 
 Within the last ten years, however, a revulsion of feeling 
 has taken place, and the impetus given by the perfection of 
 various electrical instruments, and by improved methods of 
 measuring currents has reached the circles of practical medicine. 
 In France there are at present two periodicals devoted to 
 medical electricity', and in the United States ther. is an 
 Electro-Therapeutical Association ; simplified ^nd standardised 
 instruments are being devised and the whole subject is 
 gradually being placed upon a more scientific basis. Enough 
 has been determined to prove that we have in electricity, in 
 many cases, an invaluable aid to the diagnosis and treatment 
 of disease. Every medical man who wishes to be abreast of 
 the times should have at least a working knowledge of 
 electricity, and a Galvanic and Faradic battery should form 
 part of his every-day equipment. 
 
 Most of you are more or less fVuniliar with the appliances 
 which are in use at the various hospitals, but much of your 
 knowledge is, I fear, a seething mass of heterogeneous facts, 
 and in the following pages I will endeavour to restore order 
 out of chaos in as concise and simple a manner as possible. 
 
 Before passing on to the medical aspects of the subject, it 
 would be well to have in mind a few facts in elementary 
 Physics which are essential to a clear understanding of the 
 matter. 
 
 ELECTRO-PHYSICS. 
 
 Three methods are employed for generating electricity, viz.> 
 the Galvanic or Voltaic cell, the Faradic battery, and the 
 Static machine. 
 
 The production of an electrical current by means of 
 chemical energy was discovered by Volta about 1800. He 
 
invented what he called a ' pile ', made up of alternate discs of 
 copper and zinc, separated from each other \>y a disc of flan- 
 nel soaked in acidulated water. It was found that the lowest 
 copper plate was negative, while the upper zinc one was 
 positive. By attaching wires to the two metal terminations 
 of the pile and Joining thern, there was generated what was 
 ciilled a ' current ' of electricity passing from the zinc to the 
 copper. 
 
 Volta improved upon this by taking a number of glass 
 vessels which contained diluted sulphuric acid. In each of 
 these he placed a plate of zinc and one of copper. The 
 copper plate of one cell was connected by a copper wire to 
 the zinc of the next, and so on. When the last plates of zinc 
 and copper were connected, a current of electricity was set 
 up which passed from the zinc plate to the copper. What 
 happens in such a battery is this. The sulphuric acid is 
 decomposed, the hydrogen or positive element being evolved 
 at the copper or negative plate, the positive or S O ^ — 
 element uniting with the zinc to form zinc sulphate. This 
 effect is called polarisation, because the molecules of the 
 acid are all arranged in the same direction. When impure 
 zinc is used, it is found that it dissolves rapidly, and it is 
 generally amalgamated in order to obviate this. A battery 
 such as this of Volta's very soon deteriorates, and many 
 other devices have been made use of. The cell most used 
 for medical purposes is the Leclanche cell. This consists 
 of two parts. A porous pot enclosing a rod of carbon 
 packed around with manganese dioxide, is placed in a glass 
 jar containing ammonium chloride in solution. In this 
 solution a zinc rod is immersed. Such a battery gives a 
 very constant current and lasts a long time without replenish- 
 ing. About thirty-six or more of such cells are combined in 
 a suitable case. On the cover of this case is a device for put- 
 ting as many cells as may be desired into operation at once, 
 together with a galvanometer, and a rheostat. The best 
 instrument is perhaps that made by Gaitfe of Paris. 
 
 The principle of the Faradic battery is as follow^s. Accord- 
 ing to a law discovered by Faraday, at the mo^nent ichen a 
 current is formed, it produces in a conductor near it a. 
 momentary current in an inverse direction to itself ; also, 
 at the moment tuhen such a current Is broken, it produces in 
 a neighbouring conductor a momentary current in the same 
 direction as itself. 
 
 n 
 
I "n'li'H 
 
 6 
 
 .. n the Ruhmkol-tt' coil t\u\ prototype of the modern fanulie 
 hatteries, there is a central core of soft iron, wound as a hohbir 
 with coarse copper wir(> insulated. Endosinjj this is a hollow 
 bobbin wound with fine insulated copper wire. The coil of 
 coarse wire is calK'd the prunary coil ; the coil of tine wire 
 outside it is the necondary coil. When a current from a 
 galvanic battery is passed tlu'ough the primary coil, a current 
 of electricity is produced or induced in the secondary coil in 
 the opposite direction. This induced current is only momentary 
 and excited at the moment when the current is rent into the 
 primary coil. When the current in the primary coil is cut 
 off there is also a current induced in the secondary coil, but 
 in thp some direction, ''.'hus in the outer or secondary coil 
 we ^et alternatinj:,^ currents produced by the making or break- 
 ing of the current in thc^ primary coil. This interruption oi 
 the primary current is brought about by a lever with a soft 
 iron head, which is placed near the soft iron core of the 
 primary coil. When the cuirent passes in, the lever is at- 
 tracted by the magnet which is produced and a break is made 
 in the circuit. When this occinvs the soft iron cor? ceases to 
 be a magnet and the lever fiies back like a spring only to 
 re-e.stabli.sh the circuit. Thus the making and breaking of 
 the ^current is automatic. This can best be explained by a 
 diagranj. 
 
 F 
 
 F is the galvanic cell. P and N the conducting wires to the primary 
 coil. B ip the primary coil. A is the secondary coil. C is the soft iron 
 core which can be temporarily made a magnet. D is the interrupter. E 
 the c\. .ducting post. G and H are the terminals of the secondary coil to 
 which suitable handles can be attached. 
 
The current passes through V to primary coil B and returns 
 to the cell F through D and E which are in con<^act. When 
 this happens, C l)ecomes a magnet and attracts the h.i,mmer D. 
 This breaks the contact hetween J) and E. C then ceases to be 
 a magnet, and D immediately falls back and touches E; contact 
 is made and the process is repeated. As often as a current 
 passes in B an induced current in the opposite direction is set 
 up in A. When the current is broken in B, an intluced 
 current, is set up in A but in the same direction as the original 
 current. In (J and H then we get currents passing in alternate 
 directions and lasting only for a very brief space of time. 
 
 The faradic machines most in favour are, that of Tripier, 
 which is contained in a portable box, and Oaiti'e's modification 
 of Tripier's model. This last has three secondary coils, one, 
 of coarse wire whose resistance is about 1 ohm, a second of 
 medium-sized wire with a resistance of i5 ohms, and a third 
 of fine wire with a resistance of 1300 to 1400 ohms. It also 
 possesSv:n an appliance for slowly interrupting the current. 
 The cunont is usually obtained from a (Jrenet bottle cell. 
 This is iiu flask-shaped cell filled with an acidulated solution 
 of bi-chromate of potash, and contains a plate of zinc be- 
 tween wo carbon plates. It has an electro-motive force of 
 more than two volts. 
 
 Static electricity is produced by friction. More than two 
 thousand years ago it was noticed that when amber was rubbed 
 by silk it received the property of attracting light bodies. 
 Other substances such as glass, sealing-wax, sulphur, and vul- 
 canite, possess the same properties. By the friction the state of 
 electrical equilibrium of the two bodies is disturbed and one 
 becomes positively electrified, the other negatively electrified. 
 By suitable conductors these two opposite forces can be col- 
 lected and isolated. 
 
 All the known Static machines are simply intended to facil- 
 itate friction and the collection and isolation of the positive 
 and negative elements. The best machine used is the Wim- 
 shurst-Gaiffe. In this, there are two vulcanite discs with 
 elevations on them covered with tin-foil and peripherally 
 arranged. The discs are so mounted on an axis that they can 
 be revolved in opposite directions. Friction is obtained by 
 means of four metallic brushes which impinge upon the eleva- 
 tions as the discs revolve. Metal cylinders are used to collect 
 the positive and negative electricity. The electricity from 
 one of the collectors is carried ott' into the earth b-,- a metal 
 
8 
 
 clmin, wliile tlie elocticity from the otlier is conducted by a 
 metal rod to the patient who is seated on a st"'-' insulated 
 on glass legs 
 
 It might he thought that the force generated by these 
 different forms of apparatus would practically put us in 
 possession of a number of agents essentially differing from 
 one another, but this is not so. The electric force is the same 
 no matter what form it takes. The currents generated by 
 the instruments just described are fundamentally identical, 
 although they appear to differ in that certain elements 
 predominate over the others according to the electrogenic 
 source. Thus, in galvanic currents the predominating char- 
 acteristic is quantity. The electromotive force is in the back- 
 ground. They also produce powerful electrolytic or chemical 
 effects. Thus, a galvanic current can be made to decompose 
 water and various metallic salts such as sulphate of copper*. 
 With static currents the amount of electricity generated is 
 small, the electro-motive force is great, and the tension is high. 
 The predominant element is tetusion. Powerful mechanical 
 effects are thus produced. I'he induction current is in a 
 measure intermediate between the galvanic and static varie- 
 ties. Faradic currents represent a small quantity of elec- 
 tricity which can produce powerful mechanical effects. They 
 have little or no chemical acticm. In practice, however, we 
 can obtain very similar effects. For instance, the galvanic, 
 faradic, currents, and the sparks from a static machine, give 
 rise to powerful muscular contractions. 
 
 ELECTllO-l'HVSIOLOGV. 
 
 We will now pass on to the electrical phenomena displayed 
 by nerve and muscle. In electro-physiology there are two 
 distinct factors, (1st) the electrogenic power of the animal 
 tissues themselves, and (2nd) the effect of extrin.sic electrical 
 currents upon the animal economy. 
 
 '^I'he whole subject of the inherent electrical power of 
 animal tissues has long been wrapped in mysterj'', and is a 
 very favorite debating ground for different schools of thought. 
 No douljt the living organism and portions of tissue freshly 
 detached from it have the power of generating currents of 
 electricity. The first experiment was that of Galvani. He 
 removed the leg of a frog with a considerable length of the 
 sciatic nerve attached. When the end of the nerve was placed 
 so as to touch the muscle, a single energetic contraction of 
 
9 
 
 the muscles of the leg took place. To this phenomenon was 
 given the name of the ' physiological rheoscope.' The current 
 here generated has been called by some ' the current of repose.' 
 Matteucci, I)u Bois-Reymond, and Arsonval have investigat- 
 ed the subject very fully. Currents of action have been 
 recognized. To demonstrate these two physiological rheo- 
 scopes ai'e necessary, the nerve of the second resting upon the 
 muscles of the first. When the contraction in the muscle of 
 the first takes place it is noticed that another contraction 
 immediately is set up in the second rheoscope. This was 
 calle<l by Matteucci the ' induced contraction.' 
 
 Again, if we stimulate the nerve of a physiological rheo- 
 scope so as to cause a tetanic contraction of the muscle, it is 
 found that the current of repose is nmch weakened. This 
 constitutes the 'negative oscillation' of l)u Bois-Reymond. 
 Many theories have been evolved to explain these facts, but 
 none of them have been brought to a demonstration. Suffice 
 it to .say that all vital acts are accompanied by the produc- 
 tion of several forms of energy of which electricity is one. It 
 would seem that normally the liberation of electrical energy 
 is necessary for the perfect performance of physiological 
 acts. When we come to the discussion of the external appli- 
 cation of electricity to nerve and muscle v/e are dealing with 
 a subject which is of more practical value. 
 
 N:.'rves and nmscles can be stimulated by a variety of 
 agents. Of these electricity is one. The tissues of the body 
 present very great resistance to the passage of the electric 
 current. Through dry skin it can hardly pass at all. When 
 the skin is moistened the resistance is lessened although 
 still relatively very great. Conductibility is best in the 
 muscles, next best in the tendons, and in the other tissues 
 in the following order ; the fat, the cerebral substance, 
 aponeuroses and bone. When a galvanic current is passed 
 into the tissues what happens is this. The electric current 
 naturally follows the path of least resistance, and if the 
 conductinii' medium were homofjeneous the matter would 
 be quite simple. The current would simply break up into 
 streams of equal size an<l pass from one pole to the other 
 by the shortest path. In living tissues, however, the result is 
 quite d'fi'erent. Here we are dealing with a mass made up of 
 substances of very different conducting power. Practically, 
 then, the current breaks up into innumerable streams of 
 differejit sizes an«l intensity, and these streams take their way 
 
 x 
 
10 
 
 to the negative pole by irregular zig-zag paths, avoiding the 
 bones and aponeuroses whicli they cannot penetrate. A few 
 practical hints can be deduced from this. When it is intended 
 to electrify a particular spot, a small electrode is used with 
 firm pressure in order to somewhat condense the tissues. In 
 this way the parts immediately beneath the small electrode 
 receive the full strength of the current, which is immediately 
 afterwards broken up into finer streams, which very slightly 
 affect any other part. When it is intended to electrify a 
 section of nerve, two small electrodes are chosen and pressed 
 fiiMuly over the trunk of the nerve. In electrifying muscles 
 it is found that the maxinmm contraction is only obtained by 
 applying the electrodes in a certain way. Duchenne first 
 noticed tluit when one of the electrodes was placed over the 
 point at which the motor nerve entered the muscle and the 
 other some distance away, he got violent contractions with a 
 relatively weak current. To such spots the term "motor 
 points" has been given. Charts are now made out showing 
 the motor points for nearly all the muscles of the body, and 
 single nmscles can be picked out and electrified either 
 directly or indirectly. When it is desired to affect extensive 
 superficial tracts of the body large electrodes are used. By 
 appi'opriate methods it is possible, according to Erb and Von 
 Ziemssen, to electrify even the brain and spinal cord. 
 
 Nerve trunks can be stinmlated by either the galvanic or 
 faradic currents ; this stinmlation being evinced, in the case of 
 motor nerves, by the contraction of the muscles they supply, 
 in the case of sensory nerves by the sensation elicited. 
 When a galvanic curi'ent is passed along a section of nerve, 
 there are produced at the two poles two regions of altei-ed 
 nerve iri'itaVnlity with a neutral zone between. In the neigh- 
 Ijourhood of the positive pole both the irritability of the nerve 
 and its conducting power are diminish;'d. To this diminution 
 of irritability and con<lucting' power the name anelccfrutonus 
 has been given. At the negative pole, on the other hand, 
 these (|ualities are increased and to this the name katelectro- 
 tonus is applied. It may be illustrated thus : 
 
 kl iJ 
 
 Let the horizontal hne represent a section of nerve terminating in M 
 the muscle. B is the positive pole and C the negative. N P is the neutral 
 point, A is the zone of anelectrotonus, and K the zone of katelectrotonus. 
 
11 
 
 The longer the current is applied and the stronger it is, the 
 greater becomes the area of A, and cons(;(|uently the less 
 becomes the area of K. In othei words the neutral point 
 gradually approaches the negative pole. When a downward 
 current is sent into such a section, i. e. when the circuit is 
 closed, the impulse starts from K and to reach M has only to 
 pass through the normal nerve l)etween C and M. Thus the 
 impulse reaches M unimpaired. Again when the circuit is 
 broken the impulse starting from A has only to pass through 
 K whose conductibility is plus and through the secticm of 
 healthy nerve between C and M. It thus reaches M also 
 unimpaired. It is then clear theoretically, why, with des- 
 cending currents, such great movements are induced both at 
 the making and the breaking of the circuit. 
 
 In the case of ascending currents the result is somewhat 
 different. 
 
 c - 
 
 «1 
 
 ■'-"nP 
 
 B 
 
 When the circuit is closed the impulse generated in K has 
 to pass through A, which is the zcme of minus irritability, in 
 order to reach M. Therefore with ascending currents the 
 contractions induced on closing the circuit are either very 
 sliffht or else nil. 
 
 When, however, the circuit is In'oken the impulse generated 
 in A reaches M unimpaired. In accordance with this it is 
 found clinically that descending currents an; more powerful 
 than ascending ones. It follows from this, too, that the 
 breaking of a current running in one direction renders the 
 nerve more suseeptil)le to the making of a current running in 
 the opposite direction, and less sensitive to curnnits running 
 in the same direction. The rea.son is that when the direction 
 of the current is suddenly reversed anelectrotonus becomes 
 katelectrotonus, while in the case of currents running in the 
 same direction anelectrotonus remains anelectrotoinis. It 
 now becomes very plain why the alternating curi'ents of an 
 inductorium have so much more power to cause muscular 
 contraction than the galvanic current. Nevertheless, if 
 the galvanic current be slowly reversed very powerful contrac- 
 tions are induced. 
 
li 
 
 When tlie faradic current is applied tt) a motor nerve, the 
 impulses come so quickly that the muscle has not time to 
 relax, and is thrown into a state oi' tetanic contraction which 
 cimtinues just so long as tlie stimulus is applied. In the case 
 of the galvanic current it is different. Contraction only 
 occui's when the current is made or broken It', however, the 
 current could be rapidly interruj^ ted, no doubt a tetanic 
 contracticm would result in this case also. 
 
 The sensory nerves arc stimulated both by the galvanic and 
 faradic currents. Tlie stimulation of the sensory nerves by 
 galvanism continues so long as the current is passing, but is 
 greatest at the times when the circuit is made or broken. It 
 seems probable that the motor nerves are also stimulated all 
 the tinie that the current is passing, and not merely when it is 
 made or broken, although the stimuhis is far too slight to 
 produce a noticeable reaction in the muscles. As a rule the re- 
 actions of sensory nerves obey the same laws as those of the 
 motor nerves. Here, too, the negative pole is the most active. 
 
 Faradisin profoundly affects the sen,sory nerves, and is of 
 value, among other things, to determine the state of cutaneous 
 sensibiTH'. Not only are the cutaneous nerves affected, how- 
 ever, buL he nerve trunks also. The sensation produced is a 
 slight pricking, sometimes amounting to actual pain, accord- 
 ing to the strength of the application. Immediately after 
 faradisation, cutaneous sensibility (tactile) is diminished ; 
 later it is exalted. This fact has be^n utilised to relieve 
 cutaneous ana-sthesia. The application of faradism to nerve 
 trunks causes a sensation of stinging and nund»ness extending 
 to the periphery. 
 
 \Vc now pass on to the action of electric currents upon 
 normal muscle. This subject is not quite so simple as the 
 last, for the reason that we are dealing with two factors, the 
 nerve terminals, and the muscular fil)res themselves, 
 
 The nerve endings are more susceptible to faradism than 
 the muscle fibres, for the reason that the nmscular fibres are 
 unable to respond to very short impulses. This is proved 
 experin^entally by injecting curara. This drug dulls the sen- 
 sibility of the motor nerve terminals, and it is found that 
 under these circumstances the muscles take a stronger faradic 
 current to make them react than they did before. It seems 
 probable, tiien, that the reaction of muscle to faradism is 
 normally through the nerve terminals. With a slowly inter- 
 rupted faradic current there is a contraction induced every 
 
 i 
 
 (U 
 
13 
 
 i 
 
 iU 
 
 i 
 
 time the current is made or broken. Whea these interrup- 
 tions occur oftener tluxn forty to the second, tetanus results, 
 and continues so king as the stiinuhis is applied 
 
 With jijalvanism contractions only take pla. when the 
 current is made or broken. Probably here, too, tl\e stimula- 
 tion comes through the nerve terminals. 
 
 In the case of disease, the electrical reactions depend on 
 two factors, the state of the nerve supplying the muscle, and 
 the state of the muscle fibres. When the nerve is diseased, 
 we get certain alterations in the mu.scular response. 
 
 When a nerve trunk is degenerating, it presents an in- 
 creased resistance to the conduction of stimuli, for the reason 
 that many of the nerve fibres are profoundly altered. Such 
 a nerve will only react to very strong galvanic or faradic 
 currents. If degeneration is complete, it will not react at all. 
 As a consequence of this pathological condition, the muscle 
 supplied by the nerve degenerates, and finally atrophies. 
 Such a muscle, if degeneration is partial, will react to 
 faradism, but only to a stronger current than normally. 
 Gradually it loses this power, and finally will not react at 
 all. With galvanism the results are different. 
 
 In the case of a healthy muscle what occurs is this : If a 
 modei'ate galvanic current is used, the negative pole (^Cathode) 
 being placed over the muscle, and the circuit made, a strong 
 contraction takes place. When the positive pole (Anode) is 
 placed upon the muscle, and the circuit made, a contraction 
 is observed, but not so forcible. There is no reaction on 
 opening the circuit. With a stronger current opening con- 
 tractions are produced, and the Anodal contraction is greater 
 than the Cathodal. To put it graphically, — 
 
 ACC is less than CCG 
 and A(K' is greater than COG 
 This formula is called the normal reaction of healthy muscle 
 to galvanism. 
 
 The reaction of degeneration is simply a more or less 
 perfect i-eversal of this formula. 
 
 If degeneration is partial, we may get — 
 
 ^CT; equal to CCG 
 and ^OC equal to C'OC 
 
 If degeneration is more advanced the formula is — 
 AGG greater than GGG 
 and AOG less than COG 
 
14 
 
 When the lattftr reaction has been established, if the muscle 
 continues to dagenerate, stronger currents ai-e required to 
 produce any effect. The anodal closing contraction is the 
 last to be lost, and finally the muscle i'ails to react to any 
 current. When recovery occurs the contractions reappear in 
 the reverse order. But, beside this quantitntive change, there 
 is a (jualitative one. The wave ot' contraction instead of 
 being short and sharp is distinctly slowed and of a wider 
 amplitude than in health. It is found, tuo, that a degenerat- 
 ing muscle often reacts to a weaker galvanic stimulus than it 
 would do when normal. This is said to be due to certain 
 nutritional changes which increase th..' functional irritability, 
 a condition called by the older pathologists ' irritable 
 weakness.' 
 
 To have a perfect reaction of degeneration the following 
 elements are necessary : 
 
 1. Diminution of excitability to faradism. 
 
 2. Increased excitability to galvanism. 
 
 3. A sluggish, ample contraction to galvanism. 
 4 A reversal of the normal fornmla. 
 
 The order in which the chanj^es occur is as follows : The 
 muscle first loses its power of responding to rapidly inter- 
 rupted faradic or galvanic currents, then to slowly inter- 
 rupted faradic currents, then to slowly interrupted gal- 
 vanic currents, and finally, to slowly reversed galvanic cur- 
 rents. 
 
 Let us now come to the practical application of these facts. 
 Electricity is of use in practical medicine for three distinct 
 purposes, diagnosis, prognosis, and therapeusis. 
 
 The first two it will be convenient to discu-ss together. 
 
 The integrity of a muscle depends primarily upon special 
 nutritive centres which are supposed to exist in the anterior 
 cornua of the spinal cord, upon the condition of the nerves 
 supplying the muscle, and upon the state of the muscular 
 fibres themselves. In addition, there are certain centres and 
 tracts in the brain which have to do with the originating 
 and transmission of impulses to the muscles. In other words, 
 there is an upper and a lower motor segment. 
 
15 
 It may be illustrated by this diafjram : 
 A (^C is the cortical inot'>r cell. 
 
 SC is the spinal centre. 
 UM S 
 
 P the peripheral nerve. 
 
 V UMS the upper motor segment, includes the whole motor 
 tract above the Bpinal cell. 
 LM S 
 
 LMS the lower motor segment, includes the spinal centre 
 p SC and everything below it. 
 
 M 
 
 D 
 
 / 
 
 M is the muscle. 
 
 Lesions of the upper motor segment often give very wide- 
 spread objective signs, inasmuch as a small lesion in the tract 
 will damage a great number of nerve fibres, since these 
 fibres are often quite close together, e.g., in the internal 
 capsule. Lesions of the lower motor segment produce more 
 localised effects. The differences between lesions of the upper 
 and lower motor segments may be tabulated thus : 
 
 UPPER MOTOR SEGMENT. 
 
 Paralysis. 
 
 Spasm. 
 
 Increased kneee jerks. 
 
 No atrophy (except from disuse.) 
 
 No reaction of degeneration. 
 
 LOWER MOTOR SEGMENT. 
 
 Paralysis. 
 
 No spasm. 
 
 Diminished knee jerks. 
 
 Atrophy. 
 
 Reaction of degeneration. 
 
 So lor g as the spinal cell SC is intact and the fibres convey- 
 ing impulses from it, the nutrition of the muscle M is not 
 impaired and no atrophy takes place. But if the track is 
 interrupted anywhere between SC and M paralysis and rapid 
 atrophy result. In acute and chronic anterior poiio-mylitis 
 the cells SC are affected. The peripheral nerves may be 
 affected from traumatism, multiple neuritis, chronic lead- 
 poisoning, diphtheritic neuritis and some other diseases. 
 When the lower motor segment is affected we get an alteration 
 in the electrical reactions of the muscles and nerves. If the 
 reaction of degeneration is perfect then the lesion is a 
 pei'ipheral one. If the lesion is higher up the reaction of 
 degeneration may or may not be complete. If tiie muscle M 
 alone is affected as in ir progressive myopatiiy the muscle 
 reacts so long as then re any fibres left to do so. There is 
 no true reaction of degeneration. 
 
16 
 
 In the case of lesions of tlie upper motor se(,'nu'nt the case is 
 dirt'erent. Hei'e the nutritive cells SC still exert their inHu- 
 encc over tlie muscle. Such lesions may be produced liy 
 traumatism, tumours, ahscess, emholism, haimorrhage, trans- 
 verse lesions of the cord, syringo-myelia, Inilhar-jiaralysis, and 
 amyotrophic lateral sclerosis. No true reaction of dejrenera- 
 tion occurs in such diseases, nor is there nui.scular atrophy. 
 
 It is true that in such cases the muscles eventually atrophy 
 and lose their electrical irritalality, but this only occurs late 
 on in the course of the disease, and is lai'^^ely an atrophy of 
 disuse. It is never extreme. The eh'cti'ical irritability too 
 may persi.st for years althouj^h somewhat diminished. 
 
 It wdl thus be seen that the electrical reactions may give 
 us very valuabli' information as to the condition of the nerve 
 trunks and even of the nerve centres them.selves, and often 
 help us to determine the site of the lesion. 
 
 When the electro-irritability of muscli!s is l(«t in the course 
 of a fiiw days we can infer that the lesion is either an acute 
 myelitis, hfemorrhaijfe into the cord, infantile palsy, or some 
 att'ection of the pej-ipheral nerves. To diagnose between these 
 diseases it is necessaiy to consider other factors l»e.side the 
 electrical reactions. On the other hand if the electro-irrita- 
 bility of the muscles remains intact for some weeks the lesion 
 is either cential, or, if in the cord, is not one that interferes 
 grt'atly with the transmission of trophic inipuLses. In some 
 cases of palsy the electro-contractibility is really or apparently 
 above the normal. This pos.sibly denotes an acute hypenemia 
 or a functional increa.se of irritability of the cord 
 
 In chronic lead-poisoning most of the paralysed muscles 
 give the retiction of degeneration, and the mu.sculo-spiral 
 nerve has lost its irritability altogether. When, however, the 
 palsy affects the Aran- Duchenne group there may be the true 
 reaction of degeneration, or again there may be diminution of 
 contraction to faradism and galvanism equally. In the latter 
 case the prognosis for recovery of these muscles is l)ad, and 
 they generally remain permanently affected. If the reaction 
 of degeneration is present the prognosis is more favourable, 
 provided further intoxication can be prevented. 
 
 In hysterical palsy the muscles react well to electricity, 
 although the application of the current may not be perceived 
 by the patient as a sensation of pain. 
 
 In determining prognosis you must always consider the 
 amount of electrical irritability in ctmjunction with the 
 
17 
 
 nature of the lesion, the manner of its onset, and the lenjjftli 
 of time it has existed. 
 
 Ordinary heiuiplej^ias may be taken as a type of central 
 palsy. Here the paralysis is the result of two distinct factors, 
 one, the amount of damage that the cerebral centres and tracts 
 have suffered, the other, the amount of damage that the 
 muscles have suffered from disuse. Should the nerve centres 
 rt 'Cover it does not follow that the muscles will likewise, as 
 they may be so degenerated thao «hey will not respond to 
 cerebral stimuli. Of course it is hard to tell how much the 
 centre is damaged, but if after -ix weeks there is no return 
 of motor power it is very likely that the centre is hopelessly 
 deranged. If, on the other hand, there is some return of motor 
 power the prognosis is better. The prospect for improvement is 
 inversely proportioned to the sti-uctural health of the muscles. 
 
 The worse the condition of the muscle the better is the 
 prospect of recovery. The reason is that the palsy is largely 
 the effect of the muscular degeneration, and not so much that 
 of the central lesion. In such circumstances there is decided 
 hope of improvement. On the other hand, if the miiscles re- 
 act fairly well, the chances are that the trouble is mainly 
 central, and galvanism cannot be expected to exert any bene- 
 ficial influence. In any case, it is not wise to prophesy com- 
 plete restoration, for, as a rule, after the muscles have recov- 
 ered as far as they will there is still an irremediable central 
 lesion. The improvement under galvanism is rapid for a time 
 but soon ceases, and under such circumstances it is useless to 
 continue treatment. 
 
 In infantile palsy (acute anterior poliomyelitis) if the mus- 
 cles lose their electro-con tractibility very rapidly the progno- 
 sis is very bad for recovery. If a muscle fails to react to 
 galvanism, the chances are that its function is hopelessly lost, 
 but even in a few such cases slight improvement has taken 
 place. When, after some months, there is still some preserva- 
 tion of electro-contractibility, the lesion in the ^.ord is not an 
 extensive one and the muscles can be more or less restored. 
 The preservation of muscular irritability late on in the dis- 
 ease is always of better progno.stic import than it is in the 
 early stages. 
 
 In peripheral palsies the prognosis depends more upon the 
 amount of damage done to the nerve trunk than upon the 
 condition of the muscle, and it should not be forgotten that 
 when a muscle fails entirely to respond to a strong galvanic 
 
18 
 
 tmrrent, especially when slowly reversed, its restoration is 
 very unlikely to take .place. 
 
 EI.ECTUO-THERArEUSlS. 
 
 the 
 
 For therapeutic purposes electricity is derived from 
 static machine and the galvanic and t'aradic battei'ies. 
 
 Static electricity is applied by placing the patient upon a 
 stool insulated by glass legs. One of the conductors of a 
 friction apparatus is connected with his body, while the other 
 is connected with the earth by means of a riietallic chain. In 
 this manner the patient can be charged with either positive 
 or negative electricity. By means of metallic balls or j)ointed 
 tips held by the operator, sparks can be obtained from any 
 portion of the body. The phenomena which the application 
 of static electricity, or Frank linisation, as it is called, can 
 produce, are only imperfectlj'^ understood. The patient has a 
 feeling as if the body were covered with a cobweb, and the 
 hair stands on end. There is also some acceleration of the 
 pulse. Stepanow has noted a gr<>ater elevation of the sphyg- 
 mographic tracing witli an augmentation of dicrotism. This 
 would point to a lessened vascular ten.sion. According to 
 Damian an elevation of temperature was produc(!d by the 
 electro-positive state w^hile the electro-negative condition 
 lowered it. There is also an increased secretion of sweat and 
 urine, and sleep is promoted. Nutrition is stimulated. There 
 is some difference of opinion as to the identit}' of the effects 
 produced b}'' the electro-positive and electro-negative state. 
 Some say the former is sedative while the latter is 
 stimulating. As a rule the effects are analogous to those of 
 the induced current. Modifications of cutaneous sensibility 
 result and contractions of the muscles can easily be pi'oduced. 
 It has been found indeed that muscles will sometimes respond 
 uo the electric spark when they fail to do so either to farad- 
 ism or galvanism. 
 
 Galvanism is applied either continuously or discontinouusly. 
 The effect of the discontinuous application has already been 
 described. The continuous application produces a sensation 
 of pricking at the electrodes, reddening of the skin, and 
 even desquamation and vesication. Slight eedema has been 
 noticed in the neighborhood of the negative pole. 
 
 Faradisation may also be continuous or discontinuous, and is 
 applied to the tissues by means of electrodes, as in the case of 
 galvanism. 
 
19 
 
 One cardinal rule must not l)e i'orgotton. Never use elec- 
 tricity tor therapeutic purposes while the lesion is acute. In 
 an acute polio-iiiyclitis nnu'ii harm mi^ht l)e done to the 
 spinal centres by too t^arly irritation from electricity. The 
 sole value of the applicatiim is to keep up the luitrition of 
 the muscles while the centivs an; recoverini,'. With rej^^ard 
 to the choice hetvveen faradism and galvanism, always ust3 
 the current which will produce? the greatest contraction with 
 the least amount of pain. The inHiction of severe pain 
 should be avoided. Another impoi'tant point is not to tire 
 out the muscles by too prolon<;ed an application of the current; 
 for an atrophied muscle is always more easily fatigued than a 
 healthy one. 
 
 The electi'ic Huid produces stimulatiufj, sedative, electro- 
 lytic, trophic and psychical etiects. Its stimulating powers 
 are taken advantage ci' in cases of paralj'sis with atrophy. 
 
 It is remarkable what good electricity can accomplish in 
 such diseases as infantile palsy. After a few applications 
 the muscles, which, at first, would scarcely respcmd, improve 
 in tone, and, 'inally, may recover power altogether. I'he 
 result is often very gratifying. The applications must be kept 
 up for many months, however, before any lasting improvement 
 can be looked for. Many children who would otherwise remain 
 paralysed, regain the power of walking. In cases of hemi- 
 plegia it is well to wait for three or four weeks until the 
 brain gets accustomed to the irritation before applying elec- 
 tricity. In peripheral lesions, where the nerve trunks are 
 not much damaged, electrical treatment should be begun 
 early. To stimulate muscular contraction, the negative pole 
 of the galvanic battery should be placed over the motor point 
 of the muscle, and the positive some little distance away. 
 The strength of the current should be about 15 to 20 milli- 
 amperes. The seance should last about fifteen minutes. 
 
 In the treatment of lead palsy, it is well to begin with the 
 galvanic current, and as soon as the nniscles respond well to 
 this, continue with faradi.sm. 
 
 In acute myelitis galvanism to the spine has been said to 
 do good, the direction of the current being occasionally re- 
 versed. It is hardly likely that we can affect the cord itself 
 by electricity, as it is surrounded b}' bone, which is a very bad 
 conductor of electricity. The current is dispei'sed long before 
 it reaches the cord, and no changes, either vascular or nervous, 
 can be expected. 
 
20 
 
 In tlic s()-callo(l "spinal irritation," tlio application of fara- 
 (lism, l»y means of the inctallic hrusli, lias been found useful. 
 It is likely that the lieut^Ht is jinxluced through the psychical 
 conti'es, and not from any physical chanj^'e that is iiuluced. 
 
 Many cases of neurasthenia, hypochondriasis, and loss of 
 musctilar tone are hent^Hted l>\' tr,>»i(.i-al faradisation and sr(;n- 
 oral galvanisation. In api)lyin<; the foinier, the patient 
 stands on a larfje copper plate attached to one wire of the 
 inductorimn, and the other, connecte(l with a lai'<^e sponge 
 electrode, is passed rapidly over the hody. In general galvani- 
 sation, one pole is placed over the ej)igastrium, and the other 
 passed over the hody, or the galvanism may be applied in the 
 form of a bath. By this means respiration and circulation are 
 stinuilated, and it has l)een shown by Weir Mitchell that general 
 galvanisation has the power of raising the body temper- 
 ature. 
 
 The tonic influence of electricity has been taken advantage 
 of by sevenil observers in the treatment of bed sores. One ulcer 
 which was several inches wide was cured in forty-eight hours 
 by the following metluxl : — A silver plate tlie size of the 
 ulcer was piaced upon it. Some little distance away a plate 
 of zinc was applied to the skin with an intervening layer of 
 flannel soaked in vinegar. The two metal plates were 
 then connectc'. by means of a wire, a current thus being set 
 
 The stimulating power of galvanism is taken advantage of 
 in gyn {ecological pi-actice. Apostoli, of Paris, has employed 
 it with some success in the treatment of uterine fibroids, the 
 idea being to contract the mu.scular wall of the uterus, and so 
 starve the blood supply, or else to foue the tibroid into the 
 uterine cavity. 
 
 The faradic stimulus has proved valuable in the treatment 
 of chloroform and opium narc()si.s. In applying it in the case 
 of chloroform poisoning, one pole ought to be placed over the 
 phrenic nerve in the neck, and the other over the diaphragm. 
 It is rather a two-edged remedy, however, and should not be 
 used except as a last resort. 
 
 Static electricity is of much value in the treatment of hys- 
 teria and chronic rheumatoid arthritis. In the latter disease 
 the pain and stifihess are much relieved, and often the pro- 
 gress of the disease seems to be arrested. The applications 
 have to be kept up for a year or two to get nmch permanent 
 benefit, but still the results appear to be better than in any 
 other form of treatment. 
 
21 
 
 The sodative power of electricity is taken a<lvaiit«<;e of to 
 relieve pain. It niity !«' re^'anlcd as a fixed rule that electric- 
 ity is unalile to i"eli(!ve the pain resulting from acut<' inHani- 
 niation, or from gross organic lesions. Neither can it ho used 
 to reli(!ve tin; local manifestations of a systemic disease. Tims 
 in migraine, malarial and toxic neuralgias nothing can he ex- 
 piscted from its use. In cases of neuritis, however, when the 
 process has hecoin(^ chronic and th(> pain seems *.o he perpetu- 
 ated hy an ahnormal ii'ritahility of the nerve, g. vani.sm has 
 heen of value. Most authorities .seem to think that tln're is 
 an essential difierence hetwt'en the two poles. The positive 
 is sedative, and hiemo.static, while the negative is alterative, 
 irritative and caustic. To relit^ve pain, then, apply the posi- 
 tive pole ov(;r the painful spot, and the negative pole at .some 
 distance. The stnm^th of the pole should be from 10 to 20 
 niilliamperes and the cm-rent should not he interrupted or re- 
 versed. Galvanism has heen ri'conunended also in tiie follow- 
 ing diseases : Pelvic and facial neuralgia, ataxia, hy,steria, 
 neurasthenia, writer's cramp, essential contractures, and tic 
 douloureux. Faradism is not so effective hut has been used 
 in hepatic and lead colic. 
 
 Just as the clu^mical current has the power of decomposing 
 soluble salts, so, it is .said, it can decom])ose the fluids in the 
 body. This electrt)lytic action is very doubtful ; at all events 
 the fluids acted on must he immediately below the skin and 
 only slight effects can be produced. Galvanism has with this 
 idea been used for the purpo.se of dispersing morbid exuda- 
 tions and in chronic inflannnatory processes. The current is, 
 however, useful as a caustic in removing superfluous hairs on 
 the body and in destroying the liair-f')llicles. 
 
 Not much need be said about the trophic action of electric- 
 ity. (Jalvanism is the most useful and is said to promote 
 sleep and appetite. Galvanism of the cervical sympathetic 
 has been tried in epilep.sy, tri-geminal neuralgia, and in ex- 
 ophthalmic goitre, but with no reliable results. The trophic 
 powers have also been used empirically in the treatment of 
 hysteria, neurasthenia, exophthalmic goitre and gout. 
 
 The psychical effects are of value chiefly in cases of hysteria 
 and hypochondriasis. In hysterical anaesthesia tlie application 
 of faradism to the part is ofte* beneficial, and in hysterical 
 aphonia faradism to the throat oi applied directly to t'le 
 vocal cords has resulted in cure. The numerous pains of the 
 neuroses are also frequently benefited by a course of faradism. 
 
•I ; 
 
 22 
 
 Charcot invented an apparatus for the purpose of producing 
 mechanical vibration. He had observed that some eases of 
 tabes dorsalis and disseminated sclerosis were apparently 
 benefited by railway travelling. The instrument he devised 
 is in two forms, one in the shape of a helmet to tit the head 
 and the other in the form of a round cylinder which can be 
 applied to any part of the body. The mechanical atfect of 
 vibration is produced by an electro-motor. Good results have 
 followed the use of these instruments in some cases of func- 
 tional headaches and nervous vomiting. 
 
 Electricity :' . also used for cauteries, lamps, motors and 
 numerous other appliances, which need not be especially 
 mentioned. 
 
 In the preceding pages only a very rapid survey of the 
 subject of medical electricity has been presented, but sufficient 
 has been said to put before you the important facts without 
 entering too much into the regions of speculation. Much has 
 yet to be done in this department. The work at present 
 being done is mainly on the line of preparing standardized 
 apparatus in order that recorded results may be of. value 
 for comparison. One of the great difficulties at present is 
 establishing a constant system of dosage. At present with 
 our imperfect apparatus we can only determine the amount 
 of electricity, which is rendered effective, in the roughest 
 possible manner. But before long, it is to be expected, this 
 will be remedied. One important thing in the employment 
 of electricity in medicine should not be forgotten. It is not 
 to try electrical treatment in cases that are not suitable for it. 
 It is far better to apply this remedy to the class of diseases in 
 which it is confessedly of some value than to attempt to force 
 its application in unsuitable cases.