the head were elongated. It may also occasion violent cerebral congestion, flushed, bloated face, changeable mood, &c., as well as weakness and trembling of all the limbs. It seems to act in a specific manner upon the cerebellum, regulating its function of coördinating or associating the different voluntary movements. Dr. Ludlam prescribes it in the second attenuation.*

2. CONGESTION OF THE SPINAL CORD.

Treatment.-Brown-Sequard † says: "the two remedies most powerful in diminishing congestion of the spinal cord are Belladonna and Ergot of Rye. These two remedies are powerful excitants of unstriped muscular fibres, in blood-vessels, in the uterus, in the bowels, in the iris, &c. Both of them dilate the pupil; both are employed with success to produce contractions of the uterus; but each of them has more power in certain parts than the other. So that we find Belladonna acting more than Ergot on the blood-vessels of the iris, (which is the principal cause of dilatation of the pupils,) on the blood vessels of the breast, (which is the principal cause of the cessation of the secretion of milk,) on the muscular fibres of the bowels, (which is the mode of its action in strangulated hernia,) on the spincter of the bladder, which is one of the causes of success against nocturnal incontinence of urine, &c. Ergot "acts more than Belladonna on the muscular fibres of the uterus, on the blood-vessels of the spinal cord," &c.

"The excitability of smooth fibres, as well as that of striated muscles, varies exceedingly in different parts of the body. An exciting agent, as galvanism, cold, heat, or Belladonna and Ergot, will produce powerful contraction in some places, and hardly any in others. The smooth fibres of the uterus contract more than those of the bowels or the bladder, and less than those of certain blood-vessels when stimulated by galvanism; the smooth fibres of certain bloodvessels contract more than those of the uterus under the excitation of cold; still more, the blood-vessels of the cerebral lobes and the face, which contract so much when their nerve (the cervical sympathetic) is irritated, contract but very little when excited by Belladonna and Ergot, while these two excitants produce powerful contractions in the blood-vessels of the spinal cord."

"Not only have I seen the diminution in the calibre of blood-vessels. of the pia-mater of the spinal cord taking place in dogs after they have taken large doses of Belladonna or Ergot of Rye, but I have also ascertained that the reflex power of the spinal cord (most likely as a

*N. Am. Jour. Homop. Vol. X., p. 690.

Lecture on Myelitis, Spinal Meningitis and Spinal Congestion.

consequence of the contraction of the blood-vessels) becomes very much diminished under these two remedies, which in so doing act just in the opposite way to that of Strychine."

A knowledge of the above facts led Brown-Sequard to employ Belladonna and Ergot of Rye in cases of paraplegia, due to a simple congestion or a chronic inflammation of the spinal cord and its meninges, and with an encouraging degree of success. "It is now certain that these agents have really a great power in diminishing the amount of blood in the spinal cord and its membranes."

Treatment of Irritation of the Vaso-Motor Nerves of the Spinal Cord.-M. Brown-Sequard says (Lecture, &c.): "Led by the view that erosions, ulcerations, and sloughs on the nates, sacrum, &c., are chiefly due to an irritation of the vaso-motor nerves, producing alterations in the nutrition of certain parts of the skin, I have thought that alternate applications of cold and heat to the parts where there is a threatening of sloughing, by acting on the blood-vessels, so as to produce in them considerable contractions and dilatations, might prevent the effects of the irritation of the vaso-motor nerves in the spinal cord." In cases of fracture of the spine occurring in animals, followed by myelitis, he tried "the alternate application of pounded ice in a bladder for thirteen minutes or less, and followed by a warm poultice for an hour. The success of this treatment rendered the correctness of the theory probable.

Lateral Curvature of the Spine.-Pathology.-This is exceedingly simple. "It is invariably produced, in the first instance, by the unequal action of the muscles, generally, but not always accompanied by muscular weakness.

"The spinal column consists of twenty-four vertebræ-little blocks of bone, piled one on top of the other, with the intervening cartilages as elastic cushions between each, and held strongly, but not immovably, together by various ligaments, the whole forming a very flexible column, with little power to sustain itself in the upright or any other position in which it may be placed, without the aid of the muscles. The spinal column is necessarily so formed, in order to allow flexion in every direction, to accommodate the various motions of the body, and to secure pliability and elasticity in connection with firmness and strength-qualities, in this particular instance, necessary to coëxist in the same organ; the latter to enable it to sustain the burdens imposed upon it, and the former to secure immunity from shocks and the operation of counter forces.

"The muscles of the trunk secured to the pelvis below as a base, are attached all along the spine as 'guy-ropes'; and in several layers and groups, by their coördinated action sustain the spine in place, or move bout in any required direction, in the most symmetrical and perfect

manner. Excepting the slight curvature forward in the lumbar, and backward in the dorsal regions, the position of the spine and shape of the spinal column at any moment in health depends on the muscles.

"When the muscles act in harmony-the different groups being properly set off by their respective antagonists-then the spinal column. whether at rest or in motion, is always where it should be. But if the action of certain muscles is not properly antagonized, for some mus cles do not act with the same degree of force as their mates, then this harmony and coördination are lost, and the spine makes a greater flexion toward the point where is the stronger muscular action, if this action is in the transverse direction, as of the scapular muscles acting at the middle of the flexible column; but from the stronger muscular force when acting from one side at the ends of the flexible column longitudinally. That is, the spinal muscles act like a string to a bow; and if they contract more on one side, the ends of the spine are made to approximate towards that side, making the spine to swell out towards the other side; but the scapular muscles, acting at the middle, would draw the spine towards themselves, and thus this unequal muscular action may cause the spine to deviate to the right or left, to or from the stronger muscles, according as they may happen to be those that act longitudinally or transversely." (Ch. F. Taylor, M.D., 1861.)

GENUS X.-MYOTICA.-AFFECTING THE MUSCLES.

Theory of Muscular Contraction and Convulsive Diseases.-The commonly-received opinion respecting muscular action is, that "muscle is endowed with a vital property of contractility, and that the state of contraction is brought about when this property is called into action. That is to say, when the muscle contracts, this vital property of contractility is supposed to be roused or excited, or stimulated into action; and the more the muscle contracts the more is this property supposed to be acted upon." A doubt was thrown over the correctness. of this opinion by Charles Bell, who said that he had been led to suppose that muscular relaxation might be the act, and not contraction; and that physiologists, in studying the subject, had too much neglected the consideration of the mode by which relaxation is effected. D. West, in 1832, (London Medical and Surgical Journal, Vol. I.,) said, "nervous influence is imparted to muscular fibre for the purpose of restraining its contraction; and the action of the will, and of al other disposers to contraction, is simply to withdraw for a while this influence, so as to allow contractility (the peculiar property of nervous force,) to show itself." This view of the modus operandi of the motornervous influence is adopted by Dr. Charles Radcliffe, in the Gulstonian Lecture for 1860. He holds that "the true type of muscular contrac

tion is to be found in rigor mortis-that the muscle contracts, not because a vital property of contractility has been roused into activity by a stimulus, but because some antagonizing influence has been withdrawn, which previously prevented the free action of common molecular attraction in the muscular tissue." Professor Duges, of Montpellier, France, maintains that muscle contracts in virtue of its elasticity, just as a piece of gum-elastic may contract when set free from a previous state of extension. Professor Matteucci, of the University of Pisa, in 1847, advocated the same general idea. In 1848, Dr. Louis Mackall, of Georgetown Heights, Columbia, S. C., endeavored to show that nervous influence determines a state of active elongation in muscle, and that contraction proceeds from the withdrawing of this influence. The protrusion of the tentacles of the snail and bryozoon, of the tongue of the chameleon, of the head and limbs of the tortoise, the movements of muscular vessels and tubes-even muscular movements generally are unintelligible without the aid of this hypothesis. He thinks, however, that contraction, as well as elongation, are vital states of the muscle to which there is nothing analagous, either in physics or chemistry. In 1851 experiments were made by Mr. Brown-Sequard, which seemed to show that the influence of the blood of the animal system is exercised in counteracting the rigor mortis, which occurs when the vital influence is withdrawn. Later observations led him to think "that the office of arterial blood is to minister to the contractile and other forms of power; and that the the office of the nervous blood is to supply a stimulus by which the power derived from the red blood is called into action."

But all observation disproves the old theory that referred muscular contraction to any stimulation through the blood, or otherwise derived from the nervous system. The permanent contraction which comes on sooner or later in all paralyzed parts, is not in any way dependent on nervous influence. After the spinal cord has been destroyed in the lumbar region of a pigeon, says Dr. Radcliffe, the muscles of the paralyzed parts are at first soft; in a few days they become somewhat hard; in a few days more they pass into a state of permanent contraction, by which the legs are kept extended and divergent.

The cause of this contraction is the suspension of the action of the nervous system; and the contraction is permanent, because the action of the nervous system is never restored.

The bearing of these facts on the pathology and treatment of convulsive diseases is well illustrated in the convulsions produced by hæmorrhages, which we cannot believe to be associated with undue stimulation on the part of the nervous system. The vessels are at this time almost empty of blood; the heart is nearly still, and the action of the nervous system must be at the lowest point compatible with the

existence of life. Recent observations render these experiments still more important and conclusive, Drs. Kussmaul and Tenner, (Untersuch. z. Naturlehre des Menschen u. d. Thiere, von J. Moleschott, Vol. II. Frankfort, 1857), passed threads behind the common innominatæ and the left sub-clavian arteries of a rabbit, and left these threads so that they could be tied and untied in a moment. On tying the ligatures, the animal was violently convulsed; about one minute later, when the convulsions were raging at their height, by untying the ligatures the convulsions were instantly suspended. Thus it is seen that convulsion is instantly brought on by preventing the flow of blood to the brain, the medulla oblongata, the upper part of the spinal cord, and the cervical ganglia of the sympathetic nerve; and these convulsions are instantly suspended by allowing the blood to return to these organs. Convulsions, then, seem to be connected with a state of inaction of one or more of the nervous centres named.

In another experiment, the ligature was placed around the neck of the aorta a little beyond the opening of the left subclavian artery. The blood now, instead of being cut off from the head and neck, was cut off from all the rest of the body below. As the condition of things produced was the opposite of what existed in the former experiment, the result was precisely the opposite. There was immediate paralysis of the part behind the ligatures, but no convulsion, or any thing approaching to it; and it was shown that this absence of convulsion was not due to paralysis of the spinal cord from want of blood-for on compressing the carotids, so as to prevent the flow of blood to the brain the animal was instantly seized with violent convulsions.

An indirect argument in support of the inferences drawn from these experiments is derived from the fact "that drowsiness, and not convulsion, is the consequence of that capillary injection of these centres, arising from the division of the sympathetic motor in the neck, or of that venous engorgement brought about by tying the jugulars, or of that double arterio-venous congestion which happens when the sympathetic nerves are divided in the neck, and the jugular veins tied in the same animal."

Recent Discoveries and Views on Reflex Action.-So far as this mode of action concerns only the muscles of motion-voluntary and involuntary—the subject has been exhaustively worked out by Marshall Hall and his disciples. But later researches, especially those of Dr. Brown-Sequard, have led us to extend reflex action also to sensitive, vaso-motor, and tissue nerves, and have thus brought a large number of facts in physiology and pathology, hitherto imperfectly understood or vaguely styled "sympathetic," under this head. From the researches of Dr. Brown-Sequard, (see his Lecture 10.) It may be easily seen that an irritation conveyed along a centripetal nerve-fibre to the cranio