A Treatise on diseases of the nervous system

Front matter

Bn8H1 Wm

HHffiliil s

UBlIEili BBiBll

Chap. I. — Ceeebeal Congestion, .... 33

Active Cerebral Congestion. — Passive Cerebral Congestion. II. — Oeeebeal Anaemia, . . . . .61

III. — Ceeebeal H^moeehage, .... 74

IY. — Meningeal ILemoeehage, .... 114 Hematoma of the Dura Mater.

V. — Paetial Ceeebeal Anemia feom Obliteeation of

Ceeebeal Aeteeies, .... 119

' Thrombosis. — Embolism.

VI. — Ceeebeal Softening, .

VII.— Aphasia,

VIII. — Acute Ceeebeal Meningitis, .

IX. — Cheonio Ceeebeal Meningitis,

X. TUBEECTJLAE CEEEBEAL MENINGITIS,

XI. — Sttpptjeative Encephalitis ob Ceeebeitis, XII. — Diffused Ceeebeal Scleeosis,

137 166 219 231

234 246 260 278 301

Xin.— Multiple Ceeebeal Scleeosis,

XIV. — TUMOES OF THE BeAIN,

General Principles. — Perceptional Insanity. — Intellectual Insanity. — Emotional Insanity. — Volitional Insanity. — Mania. — General Paralysis. — Idiocy and Dementia.

Section II. Diseases Of Tee Spinal Cobb

PAOB

Chap. I.— Spinal Congestion, . . . . . 385

II. — Spinal Anaemia, . . . . . 396

Anaemia of the Posterior Columns. — Ansemia of the Anterolateral Columns.

III. — Spinal Haemorrhage — Spinal Meningeal H^moe-

IY. — Spinal Meningitis, ..... 444

Acute Spinal Meningitis. — Chronic Spinal Meningitis. Y. — Acute Myelitis, . . . . .456

YI. — Spinal Softening, ..... 463

yii. — scleeosis of the anteeo-lateeal columns of the

Spinal Coed, ..... 471

VIII. — Soleeosis of the Posteeioe Columns of the Spinal

Coed (Locomotoe Ataxia), . . . 484

IX. — Ttjmoes of the Spinal Coed, . . . 517

X. — Seoondaet Degeneeations of the Spinal Coed, . 523

Section III. Ceb Ebro-sp I It A L Diseases

I. — Htdeophobia, ...... 545

III. — Catalepsy, . . . . . .590

IV.— Ecstasy, 597

VII.— Multiple Ceeebeo-Spinal Soleeosis, . . . 637

VIII. — Athetosis, ...... 654

Section IV. Diseases Of Nebye-oell8

I. — Atrophy and Disappeaeance of Teophio Nerve- Cells (Peogeessive Musculae Ateophy), . 663

CONTENTS. 7

PAGE

Chap. II. — Ateophy and Disappeaeance of Motoe Neeve- Glosso-Labio-Laryngeal Paralysis

III. — Ateophy and Disappeaeance of Motoe and Teo-

phio Neeve- Cells, .... 689

Organic Infantile Paralysis. — Hypertrophy of Muscular Connective Tissue.

IY. — Functional Deeangements of Motoe Nebve-Cells, 706 Paralysis Agitans. — Writer's Spasm. — Lead Paralysis.

Section V. Diseases Of Peripheral Nerves

I. — Peeipheeal Paealysis, .... 722

Facial Paralysis.

II. — Peeipheeal Spasm, ..... 731

Facial Spasm. — Torticollis.

III. — Peeipheeal Anaesthesia, . . . .735

Anaesthesia of Cutaneous Nerves. — Anaesthesia of the Fifth Pair.

Neuralgia of the Fifth Pair of Nerves. — Cervico-Occipital Neuralgia. — Cervico-Brachial Neuralgia. — Dorso-Intercostal Neuralgia. — Sciatic Neuralgia. Index, ........ 750

Pagb

Hammond,

.

Mathieu,

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Hammond, a

21 23

Broca,

. 195

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Hammond,

LIST OF ILLUSTRATIONS.

Fig.

1. jesthesiometer,

2. Dynamometer,

3. Dynamograph,

4. Duchexxe's Trocar,

5. Electro-Magnetic Machine,

6. Cerebral Convolutions,

7. Agraphia,

8. Dynamographic Tracing op Patient affected

with Multiple Cerebral Sclerosis, " . 284

9. Dynamographic Tracing of Patient affected

with Multiple Cerebral Sclerosis,

10. Malignant Tumor of Brain,

11. Cerebral Aneurism caused by Embolus,

12. Intellectual Insanity,

13. Emotional Insanity,

14. Acute Mania, with Mental Exaltation,

15. " " " Depression,

lg «( II U ((

17. Dynamographic Tracing of Patient affected

with General Paralysis, .

18. General Paralysis,

19. Idiocy,

20. Dementia, .

21. Chronic Spinal Meningitis, .

22. Dynamographic Tracing of Patient affected

with Posterior Spinal Sclerosis, " . . 491

23. Dynamographic Tracing of Patient affected

with Posterior Spinal Sclerosis, " . . 492

24. Transyerse Section of Spinal Cord, LocTchart Clarke, . 506

25. Longitudinal Section of " " . 506

Otis, .

. 307

Prof. W. R.

Smith,

Hammond,

. 350 ii ci

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. 362 a

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, 365

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. 372

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LIST OF ILLUSTRATIONS.

Fig.

26. Tumor of Spinal Cord,

27. " " "

28. Writing of Patient affected with Mul-

tiple Cerfbro-Spinal Sclerosis, .

30. " (after photograph from Hubbard),

32. Glosso-Labio-Lartngeal Paralysis,

33. Writing of Patient with Glosso-Labio-

Laryngeal Paralysis, 84. Glosso-Labio-Laryngeal Paralylis,

38. Muscle of Patient affected wieh Organic

42. Hypertrophy of Muscular Connective Tissue,

43. " " " "

44. Muscle of Patient affected with Hyper-

trophy of Muscular Connective Tissue,

45. Writing of Patient affected with Writer's

Spash, ....

Charcot,

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651 657 661 667 680 tt

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683 684

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DISEASES OF THE NERVOUS SYSTEM

IITEODUCTIOI.

THE INSTRUMENTS AND APPARATUS EMPLOYED IN THE

DIAGNOSIS AND TREATMENT OF DISEASES OF TEE

NERVOUS SYSTEM.

Diseases of the nervous system, like those of the heart, lungs, and larynx, require special means of investigation and treatment. In no department of medical science has progress been more decided during the last decade than in that class of affections considered in this treatise, and undoubtedly a great deal of the advancement is due to the instruments and apparatus by which scientific research in this direction has become practicable.

In the present chapter I propose to describe the instruments and apparatus employed in the diagnosis and treatment of diseases of the nervous system, and to explain the methods by which they are used.

THE OPHTHALMOSCOPE.

The ophthalmoscope consists essentially of a concave mirror perforated in the centre, and of a double-convex lens. Several modifications of this arrangement are in use, but the simplest instrument is, in my opinion, the best, and this is Liebreich's.

It consists of a polished steel mirror about one and threexii DISEASES OF THE NERVOUS SYSTEM. ■

quarter inches in diameter, concave, and perforated in the centre by a hole about the one-twelfth of an inch in diameter. The edges of this aperture are bevelled so as to afford as little obstacle as possible to the passage of the rays of light to the eye of the observer.

The mirror is set into a bronze ring with a handle, and there is attached also to this ring a clip for holding a concave ocular lens, which in some conditions of refraction, either in the eye of the patient or that of the observer, is necessary in order to produce the necessary divergence of the parallel rays emanating from the patient's eye, and thus render the image of the fundus distinct. A direct image is thus obtained. The lamp, which should furnish a steady flame, is placed on the side of the patient's head corresponding to the eye to be examined, and the eye of the observer very close to that of the patient. This process gives a very satisfactory view of the fundus with the optic disk and retinal vessels, but requires care, and is more difficult than that by which the inverted image is obtained.

In this case the observer illuminates the fundus with the ophthalmoscopic mirror, and then interposes between the mirror and the eye a double-convex lens which he holds lightly between the thumb and finger, resting the ring finger on the forehead of the patient, so as to make the hand steady, and the little-finger being disengaged so as to be employed in raising the eyelid if necessary.

The object-lens should have a focal distance of about two inches, and it should be held so as to bring the focus on the pupil. The lamp is placed behind and a little to one side of the eye to be examined. In order to see the optic disk, the patient is told to look at the ear of the observer on the side opposite to the eye being examined. In this way the axis of vision is directed inward, and the optic disk readily brought into view.

These examinations are made in a room lighted only by the lamp used in the processes. It is sometimes necessary

INTRODUCTION. x jii

to dilate the pupil with atropia, in order to obtain a view of the disk, but experience and tact will generally enable the observer to dispense with this rather disagreeable procedure.

Ophthalmoscopic examinations require the observer to possess a very thorough acquaintance with the anatomy of the eye, and also with the science of optics. Unless these qualifications are enjoyed, it will be much better to send the patient to a competent ophthalmic surgeon for an examination, than to rush to hasty conclusions based on the most thorough ignorance. The real value of ophthalmoscopy in diseases of the nervous system is in danger of being disregarded through the sciolism of pert pretenders, who read papers and write memoirs without ever having seen the optic disk to recognize it.

Bouchut '* gives the following list of abnormal conditions which are of importance in the diagnosis of diseases of the nervous system :

Papillary congestion; peri-papillary congestion; papillary anaemia, partial or general ; phlebo-retinal flexuosities ; venous pulsation in the retinal veins ; dilatations of the retinal veins ; retinal varices ; phlebo-retinal haemostases ; phlebo-retinal thromboses; phlebo-retinal aneurism; haemorrhages into the retina and choroid. The diseases in which he thinks ophthalmoscopy is valuable as a diagnostic means are — the several varieties of cerebral meningitis ; cerebral haemorrhage ; chronic encephalitis ; cerebral softening ; meningeal haemorrhage ; chronic hydrocephalus ; tumors of the brain ; contusion, commotion, and compression of the brain ; general paralysis ; atrophy of the brain ; chronic myelitis ; locomotor ataxia ; tetanus ; epilepsy ; essential convulsions ; insanity, and several others of less importance.

To these may be added cerebral congestion, general and partial ; cerebral anaemia ; and the various forms of sclerosis affecting the brain and spinal cord.

1 Du Diagnostic des Maladies du Systeme Nerveux, par l'Ophthalmoscopie. Paris, 1866, p. 15.

XIV DISEASES OF THE NERVOUS SYSTEM.

CEPHALOH^EMOMETER.

Although this instrument is intended for experiments on the lower animals, it enables us to arrive at very definite conclusions relative to the condition of the cerebral circulation. I first described it in a paper read before the New York Medical Journal Association in 1868, and shortly afterward published in the New York Medical Gazette} It was devised in somewhat different form, independently of each other, by Dr. S. Weir Mitchell and myself. The instrument consists of a brass tube which is received into a round hole made in the skull with a trephine. Both ends of this tube are open, but into the upper end is secured another brass tube, the lower opening of which is closed by a piece of very thin sheet India-rubber, and. the upper opening by a brass cap, into which is fastened a glass tube. This inner arrangement contains colored water. To this glass tube a scale is affixed.

This second brass tube is screwed into the first till the thin India-rubber presses upon the dura mater, and the level of the colored water stands at 0, which is in the middle of the scale. ISTow, when the quantity of blood in the brain is increased, the liquid rises in the tube, being pressed upward by the elevation of the thin rubber closing the lower opening ; when the quantity of blood is lessened, the liquid falls by its own gravity.

It was by this instrument that I was enabled to demonstrate, in the most conclusive manner, that during sleep the amount of blood circulating in the cerebral vessels is much less than during wakefulness. 8

^STHESIOMETEE.

The sesthesiometer is an instrument for the purpose of determining the degree of tactile sensibility possessed by the

* x Also, Journal op Psychological Medicine, January, 1869, p. 47. 2 Sleep and its Derangements. Philadelphia, 1869, p. 317.

INTRODUCTION. xv

patient. The instrument was devised in 1858 by Dr. Sieveking, 1 of London. Its value in cases of aberrations of sensibility depends upon the fact, ascertained by Dr. E. H. "Weber, that the capability of distinguishing two impressions made upon the skin simultaneously, varies in different regions of the body according to the distance they are apart. In sensitive regions, as the end of the finger, the two points of a pair of dividers can be distinguished at about the twelfth of an inch apart, while in the middle of the back only one point is felt, though they are two inches apart. In accordance with this principle, the sesthesiometer is used to determine the sensibility of the skin in various diseases, it being well known that this is subject to variation.

Thus when the sensibility is intact, two points, touching the back of the hand at the same time, can be distinguished as two points when separated an inch. If, in examining a patient, we should find that, when the two points were two inches apart, the patient felt but a single impression, we should know that he had lost sensibility in the cutaneous nerves of that part of the body.

Dr. Sieveking's sesthesiometer is nothing more than a beam-compass. It consists of a rod of bell-metal four inches in length, graduated into inches and tenths of an inch. At one end is a fixed steel point ; another steel point is made to slide upon the beam, and can be fixed at any distance from the first by a screw which works at the top of the slide.

In 1861 2 1 described an sesthesiometer which I believe was the first used in this country. It consisted of a pair of dividers, to one arm of which the arc of a circle, in brass, was affixed. This arc was divided so as to measure tenths of an inch. A short time since, I suggested to Mr. Stohlman, the instrument-maker, a modification of this instrument, which for convenience is, I think, superior to all

1 Brit, and For. Med.-Chir. Rev., January, 1858, p. 281.

2 A Clinical Lecture on Chronic Myelitis. Delivered in the Baltimore Infirmary, March 16, 1861. American Medical Times, January 8, 1861, p. 379.

XVI

DISEASES OF THE NERVOUS SYSTEM.

others. This, as closed, for the pocket-case, and open, as in use, is seen in the accompanying woodcut (Fig. 1) l and need not be further described.

The minimum normal distances at which the two points of the sesthesiometer can be distinguished in different regions of the body are stated in the following table : a

Point of the tongue £ a line.

Palmar surface of the third finger 1 "

Red surface of the lips 2 lines.

Palmar surface of second finger 2 "

Dorsal surface of third finger 3 "

Tip of the nose . . 3 "

1 First described by me in the Journal of Psychological Medicine, October, 1868, p. 830.

2 This table is quoted from Miiller s Philosophy, translated by Baly. London, 1840, p. '752.

INTRODUCTION. xvii

The palm over the heads of the metacarpal bones 3 lines.

Dorsum of tongue, one inch from the tip 4

Part of the lips covered by the skin 4

Border of the tongue, an inch from the tip 4

Metacarpal bone of the thumb 4

Extremity of the great- toe 5

Dorsal surface of the second finger 5 "

Palm of the hand 5 "

Skin of the cheek 5 "

External surface of the eyelids 5 "

Mucous membrane of the hard palate 6 "

Skin over the anterior surface of the zygoma 7 "

Plantar surface of the metatarsal surface of great-toe. . 7 "

Dorsal surface of the first finger 7 "

On the dorsum of the hand over the heads of the metacarpal bones 8 "

Mucous membrane of the gums 9 "

Skin over the posterior part of the zygoma 10 "

Lower part of the forehead' 10 "

Lower part of the occiput 12 "

Back of the hand 14 '•

Neck under the lower jaw 15 "

Vertex 15 "

Skin over the patella 16 "

" " " sacrum 18 "

" " " acromion 18 "

The leg, near the knee and foot 18 "

Dorsum of the foot, near the toes 18 •*

The skin over the sternum - 20 "

" " " " five upper vertebrae 24 "

" " " " spine near the occiput 24 "

" " in the lumbar region 24 "

" " " ". middle of the neck 30 "

" " over the middle of the back 30 "

The middle of the arm 30 "

THERMOMETER.

The thermometer is of use for the purpose of determining variations of temperature in different parts of the body. It should be graduated in tenths of a degree, and be held upon xviii DISEASES OF THE NERVOUS SYSTEM.

the part subjected to examination so long as the mercury continues to rise or fall. Comparative determinations must be made under precisely similar conditions.

becquerel's disks.

By means of these little instruments very slight variations of temperature can be ascertained. They consist of an extremely thin plate of copper, about the size of a half-dime, soldered to a thin rod of bismuth. This latter is contained in a small tube of hard rubber furnished with a handle. The disks are two in number, and by means of delicate silk-covered wires are in communication with the poles of a galvanometer. If a lower extremity, for instance, is subjected to examination, one of the disks is placed upon it and the other upon the corresponding part of the other limb. If the temperature of both limbs be the same, the needle of the galvanometer remains quiet ; if either be warmer than the other, the needle is deflected to the north or south according as one or the other limb has the higher temperature. By this apparatus very much less than the hundredth of a degree of temperature can be determined with absolute accuracy. 1

THE DYNAMOMETER.

Several forms of an instrument for measuring the strength of patients have been devised. The best and most generally applicable is that of M. Mathieu, an instrument-maker of Paris. It is very simple, and for measuring the strength of the hands leaves nothing to be desired.

It consists, as is shown in the cut (Fig. 2), of an elliptical steel spring, to which is attached a semicircle of gilt brass, upon which a scale is marked. An indicator, terminating at one end in a cog-wheel, is capable of being moved freely around the arc of the circle by a steel arm, upon one side of which, cogs, fitting into those of the indicator, are cut. One

1 See my memoir on the Pathology and Treatment of Organic Infantile Paralysis, in Journal op Psychological Medicine, No. 1, July, 1867, p. 53.

INTRODUCTION. ^

end of this arm (the lower) touches the elliptical spring, when the indicator points to the zero of the scale ; a brass sheath upon the under side of the scale keeps this arm in place, at the same time allowing it to move freely.

Fig. 2.

When the dynamometer is taken into the hand and pressed, the two sides of the spring are approximated and the steel arm, with the cogs being pushed by the lower side of the spring, turns the indicator. One great advantage of this instrument is that, when the pressure is taken off, the indicator does not return to the zero, but remains at the point to which it has been carried by the muscular power of the individual. We are thus enabled to see the extent of his strength, after he has made his effort, and do not have to watch him while he is using the instrument. It will also be seen that this dynamometer can be used to measure tactile force ; for if two hooks with cords attached be fastened to the spring at the points a and h, traction on the cords will approximate the two sides of the ellipse, and thus push the steel arm so as to move the indicator as before.

THE DTNAMOGRAPH.

This instrument, which is of great value in the diagnosis of diseases of the nervous system, is shown in Fig. 3.

It consists of the dynamometer B B, to which a togglejoint, moving a steel rod, is attached. This steel rod plays through a hole in the end of the elliptical spring and moves the lever which raises the pencil D. At A is a screw which

XX

DISEASES OF THE NERVOUS SYSTEM.

varies the point at which the rod touches the lever, and thus increases or lessens the delicacy of the indications. C is a silvered plate upon which the paper is fastened by clips. To the lower part of this plate, a strip of gilt brass, with cogs cut in it, is attached. E is a gilt-brass box containing a watch movement like that of the sphygmograph. A cog-wheel which projects above the upper side of this box fits into the cogs on the plate which carries the paper. The

Fig. 3.

wheel for winding up the clock- wort, and the wire for stopping it, or setting it in motion, are not seen in the figure, they being on the opposite side of the box.

To set the instrument in action, the sphygmograph movement is attached to the dynamometer at A. The clockwork is then wound up, and the plate holding the paper placed in the groove on top of the box E. The dynamometer is then grasped by the hand and squeezed firmly ;

INTRODUCTION. xxi

the lever is thus moved, and the plate with the paper is carried along by the cog-wheel. As it moves, the pencil traces a line on the paper, the height and regularity of which depend upon the firmness and steadiness with which the dynamometer is pressed. As seen in the cut, the plate with the paper is in motion, and has about half completed its course. The patient should not look at the paper while using the instrument.

The dynamograph, therefore, writes down the muscular power and tone of the individual, and likewise indicates the perfection of what is sometimes called the muscular sense. A person in good health will make a straight line with the pencil. If there is paralysis of the muscles of the arm, or incoordination to the slightest possible extent, the line will be irregular. The papers used may be marked with the date and the name of the patient, and thus a record of his condition is preserved.

The pencil should be of the very softest lead, and the paper should be rough and unsized. 1

This very useful little instrument is shown in Fig. 4. It is introduced open as at a. When it has perforated the

Fig. 4.

muscle under examination, the small button at the under part of the handle is pushed forward ; this propels a halfcylinder of steel against the shoulder at the end of the tro-

1 The first account of the use of the dynamograph was given by myself in the Journal op Psychological Medicine, January, 1868, p. 139.

Xxii DISEASES OF THE NERVOUS SYSTEM.

car, and thus a small piece of muscle is detached and caught in the cavity. The lower figure b represents the instrument ready to be withdrawn. By drawing the button back, the bit of fibre can be taken out, and is then ready for microscopical examination.

ELECTEICAL APPARATUS.

The electrical apparatus required in the diagnosis and treatment of diseases of the nervous system must be of two kinds : one for furnishing the primary or galvanic current, the other for yielding the induced or faradaic current. Among the machines of the first category are those of Stohrer, which are now made very satisfactorily by the Galvano-Faradaic Manufacturing Company of New York, a combination of Smee's cells which is manufactured by Dr. Jerome Kidder, Electrical Mechanician to the New York State Hospital for Diseases of the Nervous System, and Daniell's batteries, which can be obtained of any electricalinstrument maker. My own preference is for Kidder's arrangement, which gives a very equable current and causes very little trouble.

Of induced-current batteries I have on several occasions before this commended those of Kidder, which are certainly very admirable instruments. Recently, however, I have used with great satisfaction an apparatus which is figured in the accompanying woodcut (Fig. 5), which represents the Portable Excelsior Electro-Magnetic Machine manufactured by the Galvano-Faradaic Manufacturing Company, with all the new improvements attached. This figure represents a double-cell battery :

A. The graduated hinged battery-rod, to the lower end of which the zinc plate is attached ; the hinge enables the rod to be laid over horizontally when the battery is not required for action, thereby preventing an accidental immersion of the zinc plate into the battery-fluid. The graduated points on the rod exhibit the depth to which the zinc, when

INTRODUCTION. xx iii

the rod is raised vertically and lowered down, becomes immersed in the fluid, and indicates the battery-power obtained. It can be retained in situ at any desired depth by means of the binding screw. The brass spring 1 presses against the thumb-screw of the rod when this is fully down in the cell, and thereby maintains its conducting power, which becomes deteriorated if it is not kept free from acid, and perfectly clean.

Fig. 5.

B exhibits a combination of a movable platina disk, with that part of the retracting armature lever which plays against the adjusting-screw connecting it with the battery. After continued use this point of the disk becomes oxidized by the electric spark. When this happens, the shocks will be irregularly generated. The disk can be turned a very xx iv DISEASES OF THE NERVOUS SYSTEM.

little round on its pivot, whereby a fresh surface of its periphery will be brought to play against the point of the adjusting-screw.

0. The rheotome, or adjustable elastic fork. Its free end embraces the vibrating armature-spring or lever D between its prongs, so as to control the extent of the vibrations. When the rheotome is depressed, the upper end of the lever can vibrate freely. When it is raised, its prongs will, in proportion to the extent of its elevation, limit the space for the vibrations, and consequently increase their rapidity. The control of the velocity of the vibrations is of great importance in therapeutics and the diagnosis of disease. 2 is a set screw, placed to work against the elastic fork, and regulate its position laterally, with reference to the lever D. E represents the rheotrope or current-changer, between the electro-magnetic machine and the electrodes, by which the course of the primary and secondary currents can be instantly changed without moving the conducting wires. F represents the hydrostat or metallic capping, with stanchions or binding-straps and thumb-screws 3 3 attached. Interposed between the hard-rubber covering plate and top of the battery-cell is a soft-rubber packing. This capping can be tightened to the desired extent, by means of the thumb-screws 3 3 ; thus preventing the spilling or splashing over of the liquid, impeding evaporation, maintaining the strength of the battery-fluid, and maintaining the cells steadily in their proper places. The hydrostat overcomes the great difficulty hitherto experienced with all electric machines in which liquids are used. By means of this invention they are now rendered portable, and can be carried around charged and ready for use, without danger of spilling the battery-fluid. G represents an indicator or scale, affixed beneath the movable coil 4, in English and French measurement, graduated both ways, to enable the practitioner to make exact record of the intensity of the electricity applied to his patients at each seance; so determines the different

INTRODUCTION. xxv

degrees of susceptibility evinced on each occasion. As the strength of the primary current is increased by drawing out the movable coil 4, we count from left to right, when we apply that current. The intensity of the secondary current is increased by pushing inward the movable coil 4 ; in this case, we made our record from right to left. These machines are fitted up in black-walnut cases, with handles and locks attached.

Nothing can exceed the efficiency and convenience of this instrument. It possesses the great advantages of supplying both the inducing and induced currents, and enabling the physician to regulate the interruptions so as to give the shocks very slowly, a matter of great importance in the treatment of paralytic disorders.