No dissection was deemed necessary. I take for granted, that in no case does the destruction of the brain, the spinal cord,* thé great sympathetic, the nerves, viscera, produce any diminution of the muscular force. Having arrived at this result by direct experiment, nothing remains but to investigate the physiological dynamics of the muscular system. This I do not propose to engage in at present, but simply to offer a few new experiments, with some remarks, not having time to copy old ones, much less to entertain speculative views upon the subject. It may be proper to state that the cadavera experimented on, were the victims of the now prevailing epidemic which has already more than decimated the unacclimated portion of the population of New Orleans.

I. August 8th, 1847. J. F., resident 15 days-sick 9 days--dead 30 minutes-experiments lasted for one and a half hours after death. The mercury soon reached 101° in the axilla, and remained stationary. During this period about twenty flexions of the forearm took place from percussing the biceps, after having placed the limb at a right angle with the cadaver; the fingers rested over the centre of the chest or abdomen. The contractility after having been apparently exhausted, was, after some time, reinforced spontaneously without frictions, A blow upon the middle of the pectoralis major, caused a rapid, but slight jerk of the middle portion of the shoulder joint downward and forwarda rare phenomenon; for although this muscle is very contractile, the weight of the cadaver makes the shoulder a fixed point. The muscular nisust or effort is generally strong, but for motory purposes unavailing. If friction, pressure upon the upper end of the humerus, and the weight of the forearm could be obviated, the complex action of this muscle could readily be demonstrated. On semi-flexing the thigh, so as to bring the knee nearly to the vertical, the leg hanging down, clear of the floor, and percussing the rectus femoris, the foot and leg were instantaneously carried nearly one fourth of the distance towards the vertical, but returned as quickly by its gravity. The cadaver was now turned over on the face ;-the flexors of the leg were percussed-a strong nisus, but no flexion took place.

and Science, busied "in the labors of love," are mute as to the essential cause of the epidemic. No changes of the weather can be designated as satisfactory causes of the prevailing mortality.

The highest temperature at sunrise in the air, was for July, 78°, for August, 790-in my office 821° and 83°; in the ground, in a grass lot, 6 inches deep, at 3 P. M. 83 and 82o ;—the river at sunrise, 853o, and 86o; at 3 P. M. 853 and 86°. The River, in 1845 and 1846, reached in August, 3 higher than in 1847. The diurnal range of the river is hardly appreciable-generally a fraction of a degree. There occurred in the present year the most extraordinary change of temperature that I have ever noticed in the river: on the 9th of August, at sun rise, the river gave 860-the Levee 710-the street 79; on the 13th the river was 830-the 18th and 22d, 83, •—the 29th 85°; Sept. 1st, 840.

It might be well for the reflex school who spinalize almost every function, to call to mind that competent authorities might be cited, showing that children have been born with neither brain nor spinal cord. Can they point out a case in which the entire Ganglionic system of nerves was wanting?

+ It is necessary to use some such term to prevent confusion, that is, to distinguish the effort, from its accomplishment. The effort may be intense, yet many causes, chiefly rigidity, may prevent motion.

II.-At the same time, J. W., born in Boston, aged 34, resident 9 months, dead two-hours, had rigidity of the neck and abdominal muscles, with a temperature for half an hour of 1024 in the axilla, and 10512 in the rectum, while the muscular nisus in the pectoralis and biceps was strong, producing massive knots, but no functional motion.

III. On the same day-J. E., a German, aged 30, resident 18 months-died at 4 P. M. The experiments began in half an hour, and lasted an hour and three quarters. Caloricity.-Axilla, 5 minutes 102°-5 m. 103°-10 m. 103°; rectum, 13 m. 1044°; axilla, 5 m. 1024-5 m. 102°; rectum, 5 m. 104o. Capillary Circulation.* The veins of the arm were collapsed. A ligature was applied as in ordinary blood letting, though somewhat tighter-the veins became distended as in the living body, though the position of the arm was varied by elevating and depressing it, and finally, by turning the cadaver over; at all elevations, the distention continued with but little variation, though it was greatly augmented by moving the muscles of the forearm, as in ordinary blood-letting. The arm without ligation presented no venous distention. Contractility.-The arm was extended; the biceps was percussed with the ulnar edge of my hand-the arm arose to the perpendicular; the handle of the hatchet was used at intervals upon the same spot, and with a similar or rather increased effect, three or four times, after which the muscles appeared to be completely exhausted. These blows covered about one inch of the length of the flexors. I then took a piece of plank, wide enough to extend about one inch on each side of the exhausted part of the muscle;-each blow for a considerable period caused much more perfect flexions, the hand being always quickly placed on the breast; finding at length that the force was declining, I took a wider piece of plank, covering the whole length of the biceps,-upon using which, the contractions were more powerful than ever, until about twenty flexions took place. Exhaustion now quickly ensued. At 5 P.-M., the neck became rigid. A blow caused strong and prolonged nisus, with a large dense knot, lasting nearly a minute before relaxation occurred, but without changing the position of the limb. The thigh, as in case I, was semi-flexed;-a blow over the rectus femoris, produced similar effects.

IV.-August 20, 3 P. M.; air of the house 88°. N. B., born in France, aged 45, resident 18 months-dead one hour. Cadaveric hyperæmia, well marked-on turning the right or left cheek towards

* See an allusion to this subject near the close of this paper.

This was comparatively a slight case of post-mortem hypera mia, scarcely transcending the average, and falling short of many. This change often begins, even before death and during the agony in dependent parts. If the cadaver be turned on the face, in a few minutes after death, it will in many cases become so discolored as to look nearly black, especially in that portion of the tissue which was the most flushed or injected in the early stage of the disease. The vast import of this change, which in many bodies allows the blood immediately after death to run through the capillaries like a seive, flowing and re-flowing from side to side, by simple gravity, has never been appreciated in pathology nor in morbid anatomy. A pathologist, wedded to the gastric theory of fever, cannot see without a profound sensation, the faintest discoloration of the mucous membrane, even one or two days after death, while

the floor a dark red congestion of the skin took place in the dependent parts, in from three to five minutes, and so of the limbs and body. Caloricity.-Axilla, 3 m. 1024-5 m. 1024-5 m. 103°-5 m. 103°;-rectum, 5 m. 1034-2 m. 1034—30 m. axilla, 1024°—10 m. 1021° Contractility.-Flexion of the right arm was made artificially, the hand of which was made to rest on the floor, between or beyond the left ear and shoulder, the elbow having been elevated nearly over the wind-pipe, so that the arm could not return, except by overcoming the force of gravity equal to the entire forearm, not to mention the incidental friction, which the result showed to be great. A blow with a piece of plank upon the upper part of the triceps and the outer third of the deltoid, caused the extension of the arm, though. considerably short of a right angle with thebody; the forearm was dragged obliquely over the breast, flexed upon the arm, the semi-flexed fingers raking the chest ; the hand came to rest on the floor near the axilla. The experiment was repeated several times with a similar result. The motion was probably due chiefly to the outer portion of the deltoid, The flexors, (perhaps always stronger than the extensors in the dead body,) did not act with much force; a blow with the hand raised the forearm about ten degrees above the floor-with a plank ninety,—but the elevation be came less and less, from repetition. Three hours after death, a nisus only remained.

V.--August 21. A. J., born in England, aged 45, resident 9 months -dead three quarters of an hour;-observations ended the 3d hour after death. Caloricity.-Axilla 5 m. 104°-5 m. 1044°-5 m. 1043° -3 m. 105o-2 m. nearly 105°; rectum 5 m. 102°-5 m. 1021⁄2° ; axilla 10 m. 1044-5 m. 1044°-2 m. 104°. Capillary circulation, the same as in III. Contractility.-A blow with the hand caused a complete, but slow flexion, occupying a number of seconds;-the hand was carried to the outer end of the collar bone, where it was allowed to remain five minutes, when the limb was again extended. A bar of iron about six inches long, weighing exactly twenty-one ounces, was tied in the palm, extending to the tips of the fingers-percussion was followed by a slow, but uniform motion-the arm arose to the perpendicularthe hand with the weight descended gently to the middle of the breast bone. The force was so constant, the motion throughout its semicircular path so equable, that it was comparatively easy to estimate its velocity. It might seem incredible, that the hand, the arm, and the iron, should not be greatly accelerated by the force of gravity, after passing the vertical; it might be expected that they would, from the two forces coinciding, fall heavily and with increased velocity upon the chest, and not gently, as was the case :-Explanation is scarcely comprehended within the scope of this paper; yet, some of the phenomena in this case call for one. The following is offered as probable, if not demonstrative. The distribution of the muscular force tends to antagonize mushis subject, if turned on the face for a short time, say from two to ten minutes, will, at a few paces distant, look nearly like a negro--a discoloration which is despised, because it is in the skin! In morbid anatomy, as in practice, an exclusive theory ends in sciolism. The subject here alluded to requires a distinct essay, being a pathological and an anatomical as well as a post-mortem and a physical alteration.

cles whose functions are opposite, giving a tone or passive, contraction, so as to form an equilibrium so long as this power is latent and equal. Percussion destroys this equilibrium, this latency, causing an accumulation of free force like free caloric or positive electricity. This excitation induces contraction,--flexion, for example. In the mean time, the latent muscular force as well as the elasticity of the antagonistic muscles, the extensors, resist this excited force, more especially after the hand has passed its culmination, and is descending upon the breast, by which these antagonists, are put upon the stretch, so that their physiological or muscular force, combined with their physical, elastic or resilient force, may so augment as to equalize or modify the induced and gravitating forces resident in the flexors. Hence, the sum of all these forces or the resulting force, is uniform; the hand passing through equal spaces in equal times. Herein is seen a beautiful combination of physi ological and physical dynamics upon the principle of mutual compensa. tion--an aggregation of forces maintaining towards each other definite ratios-elasticity and gravity, a latent and a free force, resulting in an uniform motion. Many circumstances, however, often occur to derange this harmony of forces. It is sufficient to mention rigidity.

After an interval of ten minutes, percussion was repeated—the iron bar being still in the palm :—the arm arose towards the vertical about 45 degrees, the induced force was insufficient to complete its orbit; but instead of falling back to its original position, agreeably to the law of gravity, the hand was deflected diagonally towards the hip, which it came in contact with near the floor, illustrating the same law of compound forces, that is, the free or positive force was modified by the latent antagonistic force, and by the forces of elasticity and gravitation, resulting in a physico-vital force, the mean of all these motory elements conjoined.

In less than five minutes all motion ceased in the arm; but in half an hour its contractile power had returned, and the arm was raised as in the preceding experiment, but each succeeding elevation diminished, until the force appeared to be entirely expended again, when the experiments ceased, though, possibly, the contractility may have been reinforced afterwards.

Caloricity.-Axilla 5

VI.-August 28. A. R., dead half an hour. m. 106-5 m. 1073-5 m. 108° nearly. . Contractility. This was moderate, but increased for a time. In two hours it declined considerably. The right arm was now carried over the throat to the left, and was placed as in case IV; the deltoid and a portion of the triceps were struck. The arm, dragging the flexed fore-arm across the chest, was extended, but lacked twenty or thirty degress of forming a right angle with the body. This experiment was repeated several times.

VII.-August 23. J. F., born in Ireland, aged 19, resident 9 months; well proportioned, the bony and muscular systems rather predominant. The Agony.-Nearly pulseless; eyelids slightly parted; eyes upturned; the pupils contracted; mouth open, the under jaw forcibly drawn down'ward; respiration irregular, with loud stertor, causing the larynx and wind-pipe to descend and ascend to a great distance, with much force ; the breathing became more difficult, and more limited to the bronchial

tubes and trachea; total insensibility. In about half an hour the eyes opened with a stare, which continued until death; the globes oscillated to and fro with great rapidity, doubtlessly from the involuntary contractions of the recti and obliqui muscles, but so quickly that it was impos. sible to decide at any instant which set acted. These oscillations or tremblings of the eyes were preludes to a general rigidity or tetanic stiffness of the neck and trunk; in about ten minutes, the muscular equilibrium was for an instant broken, that is, the antagonism of the right side was overcome by the mascles of the left; the body curved laterally, and the eyes lost their parallelism at the same time. This muscular agony lasted from thirty to forty minutes, during which a series of indescribable wave-like contractions of the muscular fibres were seen to pass beneath the integuments, chiefly on the trunk. No entire muscle seemed to act at the same instant, but portions of its fibres oscillated convulsively and irregularly; sometimes in undulating lines, which trembled along their summits. These agitations, which were the most striking in the muscles of the eyes and of the chest, continued to augment; the respiration became more and more limited to the air tubes, in which, mucosity accumulated, causing rattles. The skin of the face and neck became congested and cyanosed. The muscular convulsion having reached its acme, gradually declined, each fibre trembled less and less. The respiration was now wholly tracheal. The pupils now dilated enormously. The impresssion produced on the observer's mind was that of a muscular convulsion, in which each muscle, if not each fibre had a particular agony of its own. The death of the lungs and heart, that is, the respiration and the circulation seemed to have been caused or at least accelerated by this general muscular spasm. The breathing and muscular agitations ceased for more than a minute, when an universal muscular convulsion or rather a shock ran over the entire body-a few respiratory gasps, not extending to the lungs, followed. The muscles ceased to quiver. The agony had lasted three quarters of an hour. Death was complete.--Ante-mortem caloricity : Axilla 10 m. 110°—10 m. 1104°; hand 5 m. 107°; axilla 10 m. 110°. Death.

Ante-mortem rigidity.-The under jaw was depressed by an apparently constant force, during the entire agony, keeping the mouth open. This was not a relaxation or falling of the jaw, but an active contraction of the muscles which depress it a phenomenon, which I have seen several times in both adults and children, hours before death from fevers, not to mention a similar appearance in infantile lock-jaw. The moment the breathing ceased, the nurse, a strong man, attempted to bring the jaws into contact; the fingers were placed on and near the base of the nose and on the cheeks, the thumb under the chin;-force was applied several times for about a minute, but with little effect. The rigidity had evidently set in before death. I have more than once observed in the abdominal, especially the recti muscles, a similar ante-mortem rigidity, which seemed to have reached nearly to its maximum during the agony. Post-mortem caloricity.-Axilla, 25 m. 1104-10 m. 110°; bend of the arm 107". The cadaver was now carried to the dead house— stripped-laid out in a sheet. Pupils now but little dilated; general rigidity; the muscles of the abdomen were rigid; thumbs strongly flexed