eczema, impetigo, or any other cutaneous erup

tion.

The prognosis in prurigo must always be uncertain as far as respects the continuance and curability of the disease, even when it assumes its mildest form. In old age and in worn-out constitutions it may be considered as incurable.

promptly and effectually; or, where this is ob jected to, an embrocation with one part of the oil of bitter almonds, one part of the oil of turpentine, and six parts of olive oil, will be found useful: the fumigation, however, is more decidedly useful than the embrocation, as it not only destroys the living insects, but their ova, which often escape the action of the embrocation as they lie in the rhagades.

2. The local pruriginous affections re

affinity with the general diseases which we have just described. Two of them, namely prurigo præputii and urethralis, are objects rather of surgical than of medical treatment, and therefore do not require to be noticed here; and a third, prurigo pubis, arising solely from the presence of pediculi, is cured by whatever destroys the insects that cause it. The ointment of the white precipitate of mercury of the pharmacopoeia, or an ointment made with equal parts of mercurial and sulphur ointment, answers every indication.

The treatment differs according to the variety of the disease. The mildest form, prurigo mitis, is benefited by a steady perseverance in the use of the tepid-bath, even when the disease is ap-quire a separate notice, as they have scarcely any parently for a time augmented by its employment. (Lorry, de Morb. Cutan. cap. iii. art. ii. par. ii.) When the bath cannot be procured, the skin should be regularly washed twice a day with warm water. We have observed much benefit to follow the daily use of the vapour-bath obtained in the manner of the Hindoos, namely, by seating the patient naked upon a chair, and after placing beside him a bucket of boiling water, enveloping his person and the apparatus within a large blanket, closely pinned round the neck, so as to prevent the escape of the hot vapour. The body should be gently rubbed by the hands of the patient whilst he remains in the bath; and when the temperature of the vapour falls, a hot brick should be dropped into the bucket to restore it. Mild soap or small quantities of the pure alkalies may be added to the water, when the body is immersed in the bath. We have not observed any advantage derived from the addition of sulphureous compounds.

In prurigo mitis, bleeding and active purging, followed by the internal use of sulphur and carbonate of soda or of nitre, have appeared to mitigate the itching, particularly in young and otherwise healthy subjects. If saline purgatives be employed, they should be combined with either the diluted sulphuric or the nitric acid. In prurigo formicans the same general means are necessary, with the addition of light tonics, such as decoction of sarsaparilla or serpentaria, or the solution of sulphate of quinia with the addition of diluted sulphuric or nitro-muriatic acid in doses of a fluidrachm, if the constitution of the patient be enfeebled or naturally weak. No benefit results from courses either of purgatives or diaphoretics.

Prurigo podicis is sometimes a very troublesome and very obstinate disease. It generally occurs in aged persons and those of sedentary habits; and although it sometimes depends on hemorrhoids, chronic inflammation of the rectum, or ascarides, yet it appears independently of those local diseases. The itching is intense round the anus and along the perineum, extending to the scrotum, which often appears changed in colour and consistence, becoming brown, thick, and scaly. The irritation increases at night, and varies greatly, according to the diet of the patient.

Prurigo podicis requires a different treatment according to the degree of irritation and the habit of the patient. When it is severe, and there either exist hemorrhoids or a tendency to them, local bleeding is necessary; and this is best accomplished by cupping over the sacrum. Emollient cataplasms, composed of bread soaked in a strong decoction of poppy-heads in vinegar and water, also afford much relief to the itching at night. Rayer recommends the gelatino-sulphureous lotions proposed by M. Dupuytren, especially when the parts are excoriated by friction. We have no experience of this application, and would rely more on local bleeding, and the zinc or diluted tar-ointment; or on an ointment composed of 3ss of acetate of lead, Ji of sulphate of zinc, f.ziv of tincture of opium, and 3iss of lard. We have

We have little to propose respecting the general treatment of prurigo senilis. In most instances, the disease seems connected with a worn-out languid state of the habit, and requires the aid of a chalybeate, either natural or artificial; we pre-seen much comfort derived from the daily employ fer the former, but when it cannot be obtained, we consider the solution of the hydriodate of iron, in small doses largely diluted, as the best substitute. Some benefit has occasionally been derived from the Harrogate waters, employed internally and externally at the same time. When the itching is very severe, the warm-bath affords a temporary alleviation, and the warm sea-water bath should always be preferred to the fresh-water bath when it can be procured. When neither can be readily obtained, much benefit has followed the employment of a lotion of the bitter almond emulsion, containing one grain of the bichloride of mercury in each fluidounce of the emulsion, and one fluidrachm of hydrocyanic acid. When pediculi infest the skin, the most effectual mode of destroying them is the fumigation with cinnabar, which acts

ment of the warm hip-bath at bedtime, and the cold hip-bath in the morning. Little internal medicine is requisite: the secretions should be improved by the administration of very minute doses of calomel, namely, one-sixth of a grain combined with three grains of extract of conium at bedtime, and half a drachm of the solution of ioduret of iron, equal to gr. iss of the salt, in a large glass-full of water twice a day. In old wornout habits, the fluid extract of sarsaparilla, in doses of a table-spoonful in half a pint of milk three times a day, has proved useful. But it must be acknowledged that this troublesome affection often resists every treatment that has been suggested.

Prurigo scroti resembles prurigo podicis in many particulars, and seems to originate in similar conditions of the habit. It requires nearly the

same treatment. Lotions made with calomel or bichloride of mercury and lime-water, without being filtered, have been found useful. When the disease arises in plethoric individuals from violent exercise in hot weather, nothing more is necessary than daily ablutions with tepid soap and water, regulating the bowels, and avoiding stimulant diet. Prurigo muliebris differs little from the lastmentioned varieties, except as regards the nature of the parts affected and the sex of the patients. It is frequently connected with leucorrhoea, especially when it appears after the cessation of the catamenia. In some instances the itching and irritation about the labia and os vagina is so intolerable as to drive the patients from society, and sometimes to excite a degree of nymphomania. In such cases leeches to the vulva, and cooling saturnine emollient and narcotic lotions are indicated. On the continent much confidence is reposed on bleeding in the feet or ankles, but we are of opinion that more benefit is derived from relieving the affected parts than by any revulsive measures. Whatever local applications are employed should be frequently changed, and thus the following may be alternately used; the ordinary black-wash; the orange-wash, composed of two grains of bichloride of mercury and a fluidounce of lime-water; equal parts of the solution of the chloride of soda of Labarraque and water; and a lotion composed of two fluidrachms of liquor potassæ, a fluidrachm of hydrocyanic acid, and eight fluidounces of bitter-almond emulsion. In one very obstinate case, the writer of this article found much benefit from pencilling the affected parts with a solution of nitrate of silver, in the proportion of two grains of the nitrate to a fluidounce of distilled water, acidulated with two minims of diluted nitric acid.

third condition differs from both of those abovementioned, yet in some points resembles the morbid. This condition is in general produced by causes which come into operation after death; sometimes, however, they may partially take effect a short time before death; and sometimes it may owe its rise to other causes, hereafter to be noticed, and only in action during life. The appearances which characterize this condition of the tissues of the human body may be denominated pseudo-morbid appearances, as being liable to be confounded with and as it were simulating those which are morbid.

Although the attention of pathologists has been a good deal directed to this subject of late years, we find but little written upon it, and the term pseudo-morbid in limited use. Dr. Yelloly, in a paper published in the fourth volume of the Medico-Chirurgical Transactions, was the first to point out that the mucous membrane of the stomach may exhibit an increased degree of vascularity under certain circumstances, independently of inflammatory action. In France, the extravagant assertions of Broussais, who, in order to establish a favourite hypothesis, pronounced every increase of redness to be indicative of inflammation, had the good effect of inducing anatomists to inquire whether other causes than disease could similarly alter the aspect of the tissues. By the researches of Trousseau and Rigot, (Archives Gén. de Méd. October and November 1826, and July 1827,) and also of M. Billard, (De la Memb. Muqueuse Gastro-intestinale,)-[see, also, Devergie, Med. Lég. 2d edit. i. 288, Paris, 1840,]—much light has been thrown upon the post-mortem changes which occur in the body, and which give rise to appearances often very similar to those of inflammation. We are likewise indebted to John HunIt is scarcely necessary to remark that, in every ter, Allan Burns, and more recently to Dr. Carslocal pruriginous affection, much heat should be well and Orfila for much interesting and valuable avoided, and a firm mattress instead of a feather-matter, which we shall presently have occasion to bed, adopted. As the irritation is always most severe in the night, much comfort may be procured at that time by applying the sedative lotions cooled in ice. If possible, friction of every kind ought to be avoided. It is also of importance to refrain from the use of all seasoned food, aromatics, coffee, wine, and fermented and alcoholic liquors, during the continuance of the disease.

A. T. THOMSON.

notice."

It may be well to state our reasons for the adoption of a hybrid term, pseudo-morbid, in preference to others more generally in use. Let it be observed that we employ the term in question to denote those appearances in any given tissue which might be mistaken for the effects of morbid action in that tissue. To apply the terms cadaveric or post-mortem to such phenomena would be to limit their number and causes; whereas it PSEUDO-MORBID APPEARANCES.-will appear in the sequel that some tissues of the There are three conditions in which any tissue or organ of the body may be found, between which it is necessary to discriminate with accuracy, in order to form correct inferences in morbid anatomy. The first of these is the natural or healthy, which we find to present certain varieties either of colour or density, according to the age of the subject. The second is the abnormal or morbid, and is to be regarded as the result either of some perversion of the development of a part, or of the influence of disease upon it. The evidence of * Although distinct treatises on this subject are rare, this condition is derived in the one case from some we must not omit to state that it has received due attencongenital malformation, and in the other from tion in several modern works, either on morbid anatomy in general, or on particular parts of it. We need hardly certain appearances which the texture of the part refer to Andral's invaluable Treatise on Pathological exhibits, and which vary in aspect and extent, ac- Anatomy. In Laennec's work, also, and in those of cording to the duration and violence of the dis-Bertin and Hodgson, constant allusion is made to appearances supposed to be cadaveric or produced in the agony ease these are the morbid appearances. The of death.

body may present appearances which must be regarded as pseudo-morbid, and which result from the action of causes operating before death. We are not aware that the term is employed by any writer except the author of an analysis of MM. Trousseau and Rigot's papers above-mentioned, which is to be found in the twenty-eighth volume of the Edinburgh Medical and Surgical Journal, and Dr. Christison, in his very valuable and elaborate work on Poisons. Under this denomina

tion, then, we would be understood to include all appearances in the dead body which might be mistaken for morbid appearances, whether they arise from the action of causes antecedent to death, or whether they be strictly such as are now generally spoken of as cadaveric or post-mortem ap

pearances.

fact it has been proved to be so caused, over and over again, by the simple experiment of turning the body occasionally, so as to change the dependent parts; in this case the blood is invariably found to leave the vessels that were before lowest to seek those that now are so. Bodies being usually placed supine after death, the integuments on their posterior surfaces are uniformly found congested, but if the body be placed immediately after death on the face and abdomen, a similar conges tion will present itself in the integuments covering those parts.

In the great majority of cases, a more or less gradual diminution of the vital powers precedes dissolution. The influence of life in preserving the integrity of the membranes of the body, whether it act through the nervous system or in any other way, gradually diminishes, and a correspond- The effects produced by the operation of cheing change is manifested. This is most conspicu- mical affinities are apparent in the alterations in ous in the capillary circulation, which becomes the texture, the density, and the specific gravities impeded to a variable extent in several places, the of the tissues: gases are evolved, new fluids are vessels being less capable of resisting the force of formed, and the membranes are often considerably gravitation. This disturbance of the capillary cir- discoloured; in short, in the action of these affiniculation may be noticed in almost every tissue in ties consists the putrefactive process, whereby new the body. In the agony of death, the same cause, compounds are formed, and the former constituit is natural to expect, will operate to a greater de- ents of the body almost wholly vanish. We find gree, and at the same time the occasional muscular considerable variation in the period of commencecontractions, which often mark the final struggle, ment and rapidity of course of this process, not must mechanically cause irregular distributions of only as regards different bodies compared with the blood in the sanguiferous system. The extent each other, but also with respect to particular parts to which these irregularities take place is in gene- of the same body. The age and habit of the inral proportionate to the strength of the patient dividual, the quantity of the fluids, the kind of (inversely), to the duration of the struggle, and death, as well as the circumstances which preceded in some cases, we conceive, to the degree of fluid-it, the season of the year, climate, state of the atity of the blood itself (directly). Any one who has ever watched a patient in the last stage of typhus fever will not want further testimony in favour of the accuracy of the preceding statements. The general cutaneous hyperæmia of the back and dependent parts indicates that the laws of gravitation have begun to operate to a much greater extent than during the state of health. (See an interesting essay by Bourdon, entitled "De l'Influence du Pesanteur sur quelques Phenomênes de la Vie." Paris, 1823.) We may also adduce the pneumonie des agonnisans of M. Laennec, the engouement de position of Andral, or the pneumonie hypostatique of Piorry, as additional

corroborative evidence.

But even when life is in full vigour, local sanguineous determinations may occur independently of the immediate operation of disease on the part in which they appear. Thus the performance of peculiar functions may cause an afflux of blood to the particular organs; as for example, while the function of digestion is going on, we find that a marked change is produced in the colour of the mucous membrane of the stomach. Again, if any obstacle' occur to the free return of the venous blood, there is in general formed a congestion of the capillary system to a greater or less extent; this is more conspicuous where the veins are destitute of valves, as in the mesenteric veins, the pulmonary veins. Hepatic disease, by compressing one or more ramifications of the vena portæ, and some forms of disease of the heart, are very frequent causes of the local determinations to which we allude.

With the cessation of life is removed all opposition to the full scope and play of gravitation and chemical affinities, the former of which was partially in operation during life. The manner in which the fluids seek the dependent parts is clearly to be attributed to the action of gravitation. In

mosphere, are so many circumstances which exert a powerful influence on the rapidity of the phenomena of this process, as must be familiar to every one who has studied anatomy even in the most superficial manner.

To the action of these same chemical affinities, we think, may be fairly attributed, at least in part, a very evident cadaveric phenomenon; namely, that increased porosity of the membranes by which the contained fluids are allowed to transude through the coats of the canals or sacs which hold them. We say increased porosity, for it must be admitted as the result of recent experiments, that transudation may take place to a slight degree even during life. (See the experiments of Fodere on absorption; of Dutrochet; and the Observations of Bouillaud on Dropsies.) Life, then, must be supposed to operate in limiting this porosity, by preventing the action of the chemical affinities; when life ceases, these affinities come into play, and there takes place a separation of the molecules of the tissues to a degree proportionate to the extent of action of the same affinities. There is no part of the body in which we do not observe this phenomenon; it is not confined to sacs with simple parietes, but extends also to those of which the walls are compound; we observe it to take place through the coats of vessels, through the walls of any or all of the membranous viscera, and even through serous membranes.

The alterations which are produced, then, on the several organs or membranes of the body by the action of the agencies above detailed, may be stated in general to be-1. such as affect the colour of parts; 2. such as alter their density or consistence; 3. such as alter the contents of a natural cavity, as for example a serous sac, by increasing or diminishing the quantity, or altering the nature of fluid in it.

We proceed to consider these effects as they

manifest themselves in the different parts of the | the cutaneous discoloration. Here, however, the body, and we shall adopt the order usually fol- change of colour takes place from a two-fold lowed in making a post-mortem examination, com- cause, the gravitation of the fluids in the vessels, mencing with the external integument and the as well as the transudation of the serous portion cellular tissue, then proceeding to the contents of of the blood through the vascular parietes. These each of the three great cavities, head, thorax, ab- two causes generally reduce the subcutaneous tisdomen; and, finally, to the arterial and venous sue to an anasarcous condition, which of course tissues. increases with the progress of decomposition; the serous portion of the blood, too, becomes more and more tinged by the colouring matter. We need hardly refer to the common appearance of the cellular membrane under the integuments of the back, with which every student of anatomy is familiar, in proof that this is the ordinary condition of that membrane, and that too within a very short period after death, as the effect of gravitation and transudation. But as putrefaction advances, and the blood resumes its fluidity, we observe ecchymoses to form in the subcutaneous tissue, the distinction of which from the effects of contusions before death is sometimes an important task for the medical jurist, and is rendered more difficult by the fact that these ecchymoses do not seem to be formed under the influence of gravitation, being found even in elevated parts. Although it does not strictly come within the range of this article, it may be proper to mention that the following circumstances, noticed by Orfila, will assist in distinguishing these cadaveric ecchymoses from such as may have been formed by violence or otherwise before death:-1. Their situation, which will generally be found in those localities where the cellular tissue is very lax and distensible, as in the occiput, loins, eyelids, and scrotum; 2. the general evidence of an advanced stage of putrefaction presented by the dissolving condition of all parts of the body; 3. the uniformity of colour presented by these ecchymoses, which is not usually observed in those made during life. (Orfila, Leçons de Médecine Légale.)

1. The external Integument.—The alterations in colour which the skin presents after death, are almost the only phenomena which it exhibits liable to be mistaken for those of disease; and even they are so distinct in the mode of their formation, that any mistake must arise from a very superficial examination. Spots of various degrees of redness, and also varying in extent, are almost uniformly observable on the dead body. In general they are of a dark red, which increases in depth of colour with the length of time that has elapsed from the death of the subject. As this cutaneous discoloration is principally owing to the influence of gravitation, we find it uniformly on the most dependent parts, the occipital portion of the scalp, the posterior surface of the neck, the back, nates, posterior parts of the thighs and legs. That it is confined to the skin may be seen by cutting into the corion where the redness exists. It is moreover to be observed that this redness is vascular, and that the surface of the skin presents the appearance of a ramiform distribution of vessels. This is important, as characterizing the kind of discoloration arising from gravitation, and distinguishing it from that which may be the result of the pressure of ligatures or vestments, &c. on the surface before death; for in this latter the redness will be found to be diffused and uniform, without any appearance of vessels.

Subcutaneous ecchymoses, however, may be produced by direct violence applied to the body shortly after death, as has been proved by experiment by Dr. Christison, and as may often be seen in the dissecting-rooms. Effusions of blood into the intermuscular cellular tissue, it is important to bear in mind, may likewise be produced by violence to the body after death. During the winter 1830-31, we had occasion to notice this fact upon bodies which, from the then imperfect state of the laws regarding dissection, were conveyed to London tightly packed in boxes from distant parts of the country. In such bodies extensive extravasations of blood into the cellular membrane between the muscles of the back were uniformly present. This fact had been likewise previously well ascertained by the happily devised experiments of Dr. Christison on the occasion of the murders committed at Edinburgh. (Ed. Med. and Surg. Journal, vol. xxxi. p. 243.)

But cutaneous discolorations or lividities may occur in situations not dependent, and at a more advanced period after death, being phenomena purely cadaveric. When decomposition has fully set in, and gases are being disengaged in the stomach and intestines, the surface of the skin of the face and neck becomes of a livid colour; the superficial veins are full, and streaks of a dark colour indicate the course of most of them. This congestion Chaussier attempted to explain by attributing it to the compression of the right auricle of the heart by the diaphragm, which was pushed up by the stomach distended with gas; and he states that by producing a similar distension of the stomach artificially, viz. by the introduction of a fermenting mixture into it, he was enabled to exhibit similar effects on the cutaneous capillary system. The compressed right auricle causes in the blood a retrograde motion from venous trunks to branches, from the branches to the capillaries, which is the more easily done, as at this period the blood has to a considerable degree resumed its fluidity. To this fermentation and gaseous development may be attributable, as Chaussier further observes, the passage of pieces of food from the stomach into the pharynx, larynx, and bron-be remarked, although the fact cannot have escaped chi, the passage of worms into the bronchi, nasal fossæ or mouth. (Chaussier, Médecine Légale, and Table des Phénomènes Cadavériques.)

We do not find any induration of the cellular tissue of a pseudo-morbid character; but it may

the most superficial observer, as a post-mortem result, that this tissue is frequently emphysematous, and, indeed, always so after a certain period in the work of decomposition, but sometimes very soon after death, as in some low and putrid fevers,

2. The Cellular Tissue,—The subcutaneous cellular tissue is generally more or less discoloured in the neighbourhood of or immediately beneath &c.

3. The Head.-On opening the cranium, the fore diminished in quantity, or altogether removed: attention is first directed to the quantity of blood if after that period sub-arachnoid effusion of this contained in the small venous trunks which are kind exist, it is to be considered either as entirely seen ramifying on the surface of the dura mater a post-mortem appearance, or the remains of the and in the sinuses. It was long ago noticed by natural effusion, to which had been added a quanVicq d'Azyr, and subsequently by Marc, that the tity of fluid, the result of morbid action. 3. That straight sinus and torcular Herophili uniformly a diminution as well as an increase in the quantity contain coagulated blood, in consequence of the of this fluid is capable of producing serious disblood when fluid flowing to that dependent posi- turbance in the functions of these important portion. On the same principle we may expect to tions of the nervous system. It is plain, therefore, find the superficial veins of the dura mater more from the above abstract of Magendie's discoveries distended towards the posterior portion of that respecting this cephalo-spinal fluid, that it would membrane. With respect to the general appear- be always difficult, and often impossible, to decide ance of the dura mater, the anatomist has only to whether a sub-arachnoid effusion be a natural, a take care that he attributes a condition of hypera- morbid, or pseudo-morbid phenomenon. Unless mia of it, whether local or general, to its proper the effusion be very considerable, and have been cause: in consequence of the fibrous character of found very shortly after death, we cannot with this membrane, it is not liable to a diffuse discolo- certainty pronounce it to be the effect of disease. ration, such as some of the other tissues are, nor But those which are found forty-eight or seventydo we find any alterations of its consistence which two hours after death are for the most part pseudoare at all likely to be mistaken for morbid ones. morbid, being caused by the transudation of the In fact it resists the putrefactive process for a con- serous part of the blood through the vascular pasiderable time, as do all membranes of the same rietes, so much so that, in opening a body two or nature. It is proper, however, to remember that three days after death, we may invariably expect a hyperemia of this membrane may be developed to find sub-arachnoid effusion to a greater or less in the progress to decomposition, by the disengage- extent. We conceive that a due attention to ment of gas in the stomach, and the compression these facts connected with the cephalo-spinal fluids of the right auricle, in the same manner as Pro- will sufficiently account for the surprise or disapfessor Chaussier supposed some cutaneous lividi-pointment which some have expressed respecting ties to be produced, as already alluded to. the want of coincidence between the severity of symptoms and the extent of effusion.

The degree of colour of the pia mater is often increased by the same causes which we have already enumerated as influencing post-mortem sanguineous determinations; in this case it will always be found that the other tissues within the cranium which admit red blood are similarly congested. In some cases this congestion may go so far as to produce extravasation; and if the body has lain long after death, the serum effused between the pia mater and arachnoid will be more or less tinged with the red particles of the blood. We may here remark further, that sanguineous extrava

of the ventricles, will communicate their colour to the cephalo-spinal fluid, provided the natural communication of the internal cavity of the brain with the sub-arachnoid cavity be not interrupted.

When the dura mater, with its adherent layer of arachnoid, has been slit up, so as to expose the visceral layer of the latter membrane, and in fact to open into the arachnoid sac, the anatomist generally looks first for some effusion between this membrane and the subjacent pia mater. We fear that in general too much stress is laid upon the occurrence of effusions between the arachnoid and pia mater. Hence what is really a natural condition is very apt to be mistaken for a morbid one; and, on the other hand, the total absence of effusion is too often regarded as indicating a state of health, when such a conclusion can be by no means constantly deduced. The interesting dis-sations from apoplexy, if extending into the cavity coveries of M. Magendie relating to what he has termed the cephalo-spinal fluid, deserve more at tention than seems to have been bestowed upon them by most practical pathologists. The principal conclusions at which he has arrived are the following:-1. That in the state of health there exists a fluid between the visceral layer of the arachnoid and the pia mater, both of the head and spine; the quantity of which is never below two ounces in the adult, and often amounts to five in subjects of large stature, and whose cranium is not of small dimensions;-that the fluid contained in the spine communicates with that in the head, and vice versâ, so as to pass freely from one cavity to the other; and that a portion of the same fluid is found in the lateral, the third and fourth ventricles of the brain, which communicate with the space between the arachnoid and pia mater by an opening situated at the inferior extremity of the fourth ventricle, between the upper part of the spinal marrow and the valve of Vieussens. 2. That this fluid may be demonstrated in full quantity either during life, or at a short time after death; but after a period of little more than twenty-four hours it becomes absorbed, and there

With respect to the encephalon itself, it may be stated that in general (such obvious cases as apoplectic clots, abscesses or tumours being excepted) it is extremely difficult, nay, often impossible, to decide between the morbid and pseudo-morbid states of this organ. This latter state is such as manifests itself by a change in the colour and consistence of the cerebral tissue. As to colour, we find it, here as elsewhere, influenced by the quantity of fluid blood in the viscus: in the corti cal substance, from its much greater vascularity, that discoloration is most likely to appear; and it is of the first moment to distinguish it from the redness of inflammation, because we find that the same colour may be the result of an active determination of blood to the brain, as well as arise from a mechanical congestion of its membranes and substance. To determine this question it will be necessary to note accurately certain collateral circumstances-the condition of the arterial and venous system of the head generally-the degree