sions are not likely to be impaired or obliterated by any process of time, or any changes in the state of the system from any cause. Of two hundred and fifty cases collected by Dr. Gibson, "in which smallpox is said to have occurred after vaccination, it appears that by far the greater number had been vaccinated less than two years." In Dr. Thomson's account of similar eruptions, they occurred at various intervals after vaccination, from a few days to fifteen years, not warranting, in any degree, the suspicion that the power of the vaccine is weakened or exhausted by time. I am, nevertheless, disposed, on the ground of seeking the highest ultimate security, to advise revaccination. It is possible that the first infection may have been something less than complete in its action on the constitution. It is also possible that the vehement energy of an epidemic variola may require extra protection by recent and thorough subjection of the system to the mild influence of the vaccine.

To ascertain the true influence of vaccine upon smallpox, is an object of the utmost importance. I will, therefore, briefly and formally recapitulate the points fairly established, by a due consideration of the facts collected on every side.

First.-Vaccination is no longer to be regarded as exhibiting the absolute power of preventing the access of smallpox. In some persons, it does seem completely to destroy the susceptibility to variolous contagion; in all, it diminishes notably, though in different degrees, the liability to be infected.

Secondly. The introduction of the vaccine virus into the system in its genuine form, and in the proper manner, never fails to produce there such changes as to modify certainly the future influence of the variolous poison, if, under any circumstances, it should affect the constitution.

Thirdly. The modification thus asserted, does not appear to consist essentially in a diminution of the violence or duration of the first stage, the eruptive fever. This, though it is, in general, very slight, may be as severe as in casual smallpox.

Fourthly.-Nor does it appear to imply essentially a diminution of the quantity of eruption upon the skin, although the number of pustules is usually very limited in smallpox after vaccination.

Fifthly. The great power of the vaccine unquestionably consists in modifying the progress of inflammation in the variolous eruption. Hence, the slighter degree of cutaneous irritation, which terminates in numer ous instances without secretion of either lymph or pus-the less amount of matter formed in the pustules (when effusion does occur)-the sudden check given, in a majority of cases, to the suppurative process after it has commenced-the early disposition to rapid drying. Hence, the absence or transient duration of ophthalmia, which with ulceration of the cornea and destruction of the eye, constitutes the worst and most unmanageable sequel of unmodified smallpox. Hence, the rare occurrence of sloughing of the cutis, and consequent pitting, seaming, and scarring of the skin. It has now become, happily, as unusual as it once was common, to see a person deformed with these marks of smallpox. Hence, lastly, the infrequency of what is termed secondary fever,

and its mildness when it does show itself. This is well known to be the most dangerous of the several stages of unmitigated smallpox; it is tedious in duration, and leaves scarcely one constitution in a thousand, without inflicting severe injury and permanent deterioration. The convalescence from smallpox is, on this account, in the unprotected, notoriously slow. On the other hand, there is no convalescence more rapid or more perfect, than that of a patient who has been assailed after vaccination. He recovers both perfectly and promptly.

"Observe," says Dr. Gregory, "how strikingly opposed to" (contrasted with) "each other, in this respect, are the influences of inoculation and vaccination. Inoculation lessens the quantity of eruption, but does not alter, in the slightest degree, the progress of inflammation in that which is thrown out. Vaccination, on the other hand, while it does not (necessarily) affect the quantity of eruption, always influences, more or less, the progress of inflammation in it."

Sixthly.-Nor, can it be denied that, as far as we have a right to draw our conclusions from the tables of mortality, published in reference to this question, vaccination tends much more surely and effectually to the prevention of fatal results than inoculation. Thus, among the cases stated to us by Drs. Bell and Mitchell, as occurring in Philadelphia, in 1823-24, out of 248, 64 had been previously vaccinated, 1 only died; 7 had natural smallpox previously-three of these died; 9 had been inoculated-three of these died; 13 unknown-no deaths. Of those entirely unprotected (155 in number), there died 85, more than one-half-a dreadful mortality.

It is surely impossible to set, in a stronger light, the advantages of vaccination, than is done in the above paragraph. Results, similar to these, are given in the annual reports of the National Institution of Great Britain, and in every other authentic document, without exception, to which we have access.

If we ask, how this ancient and justly dreaded pestilence has been deprived of its terror, and shorn of its fatal energies, what shall be the impartial answer? Not by any change in the nature of the case, not by any loss of its inherent power over the human constitution, for the mortality among the unprotected is most appalling-greater than that of yellow fever, or, perhaps, even the plague. Nor is it owing to such protection as inoculation affords, for that practice has been obsolete for the last quarter of a century. But it is clearly attributable, and we do not hesitate to ascribe it, to the kindly influence of the vaccine-the most valuable among the generous benefits conferred upon their fellow men, by the cultivators of the divine art of healing.

MEASLES (Morbilli-Rubeola.)

A specific form of fever, eruptive, contagious, inflammatory. It is often epidemic as well as contagious. It is difficult to communicate by inoculation, but Home and Speranza affirm their success, employing blood taken from the vivid patches of eruption; and Von Katona in

oculated great numbers successfully, both with blood so taken, and with tears.

Symptoms.-Rubeola makes its appearance with the ordinary tokens of catarrh. There is rigor often, followed by heat of skin, headache, hard and frequent pulse, soreness of throat, watery redness of the eyes, sneezing, a hard and dry cough, nausea and retching. In children, convulsions occasionally attend. This state of things may continue for many days, but usually on the fourth the eruption breaks out, at first visible on the face and arms, gradually spreading over the body. It is in crescent-shaped patches of small brownish red spots, rough and a little elevated. The fever generally abates on its showing itself. The eyes suffer much from it, the adnata being covered, and the lids swollen. It begins to fade on the seventh, and soon dies away, the cuticle desquamating in minute branny scales. In the progress of measles, or at the subsidence of the eruption, pneumonia may develop itself. At this latter period, diarrhoea of obstinate character often arises. Rubeolous ophthalmia is apt to be persistent.

The prognosis in measles is generally favorable, and the danger is fairly proportioned to the attendant maladies above mentioned, the pulmonary inflammation especially. In children, the convulsions are occasionally, though not often, fatal. It sometimes happens that the fever is of low typhous type, which is unfavorable. The "striking in," or sudden disappearance of the eruption, is also unpropitious, and excites well-grounded alarm.

The diagnosis does not seem to me difficult; yet it was not until the end of the 17th century, that measles were separated from smallpox, a confusion which we should now regard as impossible.

It may be confounded with scarlatina, which has, indeed, been called confluent measles. This very phrase suggests a distinction, for the patches of rubeolous eruption are usually separated by notable intervals. In 1829, however, I saw some cases in which they were nearly confluent. In scarlatina, the deep diffused redness of the tongue and mouth is diagnostic. The catarrhal affections are prominent in measles -the sneezing, coughing, &c., and the ophthalmia, which is often absent, and very seldom severe in scarlatina.

Pathology.-One might almost venture to declare that rubeola consists in the combination of some peculiar exanthema with catarrhal fever. This affects the human constitution but once, a rule presenting very few exceptions. The eruption may occur alone, a circumstance not unfrequently met with in rubeolous epidemics-the rubeola incocta of Good, R. sine catarrho of Willan, the bastard measles of common people. Now, by this form, the susceptibility to a second attack is not destroyed, nor even impaired. Other varieties of measles are noticed by writers-R. nigra, R. maligna, R. variolosa. I have met with none of these. The concurrence of measles with typhous fever presents a livid eruption, with great danger, a compound of nigra aud maligna.

Some instructive and interesting remarks occur in Panum's account of the Faroe Islands, which I transcribe here. "In those remote and secluded places, and among their sparse population, opportunities oc

curred for observations, not easily to be made elsewhere. Measles had not visited those islands for sixty-five years; in 1846 they were introduced, and there were nearly six thousand cases in six months. It was most serious in very old people and infants; one hundred and two deaths took place. A visit to a neighbor is, among the inhabitants, a rare event, and thus the progress of the disease was rendered traceable. The eruption occurs fourteen days after exposure to infection; this is a rule, as he affirms, well made out. The catarrhal stage is not of definite duration; it may precede the eruption two or three days. The contagion was strongest in the eruptive stage. Not one of the old people who had had the disease sixty-five years before was now re-attacked, although others as old, and adults generally, were found to be as liable as children. Some young people, constantly exposed, escaped. Many hamlets, some of them of more than one hundred inhabitants, were preserved intact, under a system of strict quarantine, or isolation; even the doctors being forced to undergo purification." Contagion was found to be retained in clothing of wool and hemp.

Dr. Thomas informs me that in an emigrant ship, on board which he was passenger, measles broke out, the eruption showing itself on the fifteenth day after leaving port. Thus in many ways we fix upon a double septenary interval, as the latent period. Gregory says that the relation between the rigor or invasion of measles, and the exanthem, is of quartan type, as that of smallpox is tertian.

It would seem that the immunity given by measles is more perfect than that of any other disease. Few instances of second attack occur. It is probable that the susceptibility to it is less universal, and less uniform than to smallpox. Many escape altogether; many escape special exposure at one time, who take it afterwards with much less, as we know that persons have failed to receive it when sleeping in the same bed with a patient, who afterwards took it without knowing how.

As the eruption may exist without the catarrhal affection, so there may be an indefinitely long stage of incubation, during which the subject shall suffer from a mingled train of indefinite and oppressive ailments, all of them coming to an abrupt conclusion on the appearance, often unexpected, of the crescentic patches of brownish eruption. These circumstances have led to the notion that in this, as in all other instances of the exanthemata, so called, some injurious morbid matter is got rid of by the skin; but nothing can be more vague or conjectural than this received opinion.

Treatment. It seldom happens that the catarrhal symptoms which precede the eruption, are sufficiently severe to call for any remedial management, and the nature of the case is first shown by the appearance of the red patches on the surface. Under ordinary circumstances it is best not to interfere, farther than to keep the patient at rest, and on low diet, regulating properly the temperature of his apartment, which should be moderately, but not unpleasantly warm.

In an occasional case, something more may be required. If there are tokens of pulmonary inflammation, and the pulse will bear it, venesection may be resorted to, and the cautious use of the lancet followed

by the administration of a cathartic, combined with a diaphoretic, as the solution of Epsom salt in the infus. rad. serp. The vascular excitement being thus reduced, the diaphoretic should be continued, with some demulcent and anodyne preparation, to relieve cough and procure rest. Cups or leeches to the chest may be demanded, and the thorax enveloped in warm poultices, if the dyspnoea be severe. In children affected with much gastric disorder, and convulsions, the emetic is useful, given, perhaps, while the subject is in the warm bath, and followed by a mercurial cathartic. The eyes should be kept clean with tepid water at first, and afterwards washed with mild astringent collyria. If diarrhoea comes on, upon the subsidence of the eruption, small doses of opium will restrain it, aided by the cretaceous mixture, with kino, or by small doses of acet. plumb.

The pectoral uneasiness remaining after measles, is best removed by the persevering application of successive blisters to the chest, or the irritation of the tartar emetic ointment, while we administer full doses of Dover's powders nightly.

The sudden disappearance-"striking in"—of the eruption, is always alarming, and apt to be attended with convulsions in children; and in adults, with dyspnoea and abdominal distress. If the pulse be full and hard, we must bleed freely; but if, on the other hand, as is more common, the patient has sunk into a sort of collapse, we must resort to the highest order of stimulants. The hot bath, of 100° Fah. at least, must be made ready, while we apply sinapisms to the cold and pale, or livid surface; the camphorated tincture of opium, with the volatile alkali, and hot wine or brandy, must be given boldly and in abund ance, until the skin becomes warm, and the pulse rises.

When rubeola is accompanied with fever of typhous character, it is proper to premise a mild emetic, after which a mercurial cathartic will be of service, followed promptly by the stimulating diaphoretics, which should be persevered in, adapting the doses to the condition of the patient, and the effect produced.

The convalescent from measles requires to be treated with caution. His diet must be mild and unstimulating, though nutritious, and he must be clad warmly, and guarded from all exposure.

SCARLATINA (Scarlet Fever.)

A contagious, eruptive, pyrectic disease, characterized by a peculiar efflorescence of a very florid red hue, whence the name designating it, first described about the middle of the seventeenth century. It is often epidemic as well as contagious. It has been communicated by inoculation, and, as has been asserted, with the same effect as in smallpox, of procuring a milder disease. As a general rule, it attacks but once the same subject.

Scarlatina is divided by writers, commonly, into three varieties: S. simplex, S. anginosa, S. maligna. I regard these as mere differences in degree of violence and intensity. The attack is ushered in with irregular shivering, attended by cppression at stomach, and nausea,