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by the pasteurella. The specific bacillus of lung disease, always present in the dust held in suspension in the atmosphere of infected cow-houses, is powerless to invade the pulmonary tissue of healthy calves, but when the toxins of the pasteurella have paralysed the defensive action of the phagocytes, the bacillus penetrates the tissues and there multiplies, provoking the formation of encysted abscesses, the evolution of which, slow and progressive, continues even after the subject has been cured of the pasteurellic infection of the beginning.

It is, therefore, hoped that a prophylactic treatment of the umbilical infection will succeed in stamping out lung disease as well as white scour.

BRAXY.

THE most recent volume of the transactions of the Highland and Agricultural Society of Scotland contains a valuable article by Professor Hamilton of the Aberdeen University, on the subject of braxy. It embodies the results of the author's researches into the etiology and pathology of the disease during the last four years, and we extract the following from it:-

Nomenclature.-The disease is known in the West Highlands as "braxy," but in the midland counties of Scotland it is often called" sickness" ; while in Germany, Denmark, Norway, and Iceland the disease goes by the name of "bradsot" or brasot." Not so very long ago, so little attention had the malady received at the hands of our agricultural authorities, there was some doubt as to whether the two diseases "braxy" and" bradsot" were the same. The author's experience proves beyond. question that they are identical, and this is also the opinion of those who have gone into the matter in Norway and elsewhere. Gamgee 1 derives the name "braxy" from the Gaelic broc or brac, signifying sickness-that is to say, the sickness or that form of disease which prevails more than any other in a district. The terms" bradsot" and "braxy," however, have a certain resemblance; and philologically it may be a question whether the word" braxy" is not a lineal descendant of" bradsot," and whether both are not of Scandinavian origin. The term "bradsot" means "sudden sickness," and undoubtedly has reference to the most tangible symptom of the disease-namely, its sudden onset and the rapidity with which it runs its fatal course.

Historical.-The occasional references to it in the early literature of Scotland show that braxy has been endemic in that country from remote periods; and the intelligent descriptions of the disease given in a series of prize essays sent in to the Highland Society and summarised by Dr Duncan,2 in the essay by Stevenson in that same publication, and particularly the most observant account, according to his lights, given later on by the shepherd, W. Hogg,3 show that the disease must have been firmly established in that country, and entailed tremendous loss, at the end of the eighteenth and beginning of the nineteenth centuries. In Scotland, however, it assumed more serious proportions during the nineteenth century on account of the increase which took place in sheep-farming in the West Highlands.

Krabbe4 has collected all the Icelandic and Danish literature bearing upon the disease, and traces it backwards in Iceland to the middle of the eighteenth century. Early records of the disease in the Faroe Islands are wanting,

1 "Our Domestic Animals," Vol. III. p. 292. ""Prize ~Js"ys and Trans. Highland and Agricult. Soc.," Vol. III. 1807, p. 339. " "Prize Essays and Trans. Highland and Agricult. Soc., " Vol. I. 1829, p. 44. 4 "Bradsoten hOB Farene i Island og paa Faeroerne. Tidsskrift for Veterinaerer," 1872

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owing probably to an absence locally of veterinarians or others qualified to render an intelligent account of it.

More recently in Scotland essays on braxy have appeared from time to time, but the chief drawback to these is that they are mostly by laymen, untrained in veterinary or human medicine, and giving consequently only a somewhat popular account of the symptoms and the appearances presen.ted after death. Such are the essays of Cowan and Borthwick,l and Robertson,2 which, excellent as they are from a layman's point of view, are lacking in what might be termed "trained evidence." Somewhat of the same nature are the accounts of the malady by the Icelanders, J. Sigurdsson,3, S. J6nsson,4 and G. Einarsson.5 The first really scientific account of the pathology of the disease is that by the Norwegian Government veterinary officer, Ivar Nielsen, who likewise must be regarded as having discovered the micro-organism which is its cause. 6 Previous to the publication of Nielsen's paper in I888, and even for some time afterwards, the malady was considered to be anthrax. Williams 7 looked upon it as an anthracoid disease-as a form of septicremia simulating anthrax in its post-mortem appearances, but exhibiting no contagious properties and presenting no specific germ. Even so late as the year 1893, Steel in his work on Diseases of the Sheep (pp. 45, 46) concurs in the prevalent notion that braxy is simply another name for anthrax. In fact, such was the view which in this country and elsewhere was almost universally accepted for long alter Nielsen's paper was published, and, curiously, the tradition, here and there, still lingers amongst us. Harvey 8 was opposed to this view, so far at least as his experience went of a disease closely simulating braxy, if not identical with it, which prevails in Cornwall.

The publication of Nielsen's paper, however, put all these doubts at rest. Bradsot or braxy has nothing to do with anthrax, although occasionally the symptoms of the one may simulate those of the other. His lJUblication was followed by that of Jensen,9 a paper which cannot be too highly rated for the masterly resume it gives of what was then known of the disease, as well as for containing much original experimental evidence bearing upon it.

In the beginning of the year I896 the Norwegian State veterinary,!. N: Bruland, was sent to investigate the disease in Iceland, and the results of his visits are incorporated in papers contained chiefly in the Norsk Veterinaer­Tidsskrift. lO He brought home materials with him which were subsequently worked up by Jensen and himself, and from which Nielsen's bacillus was obtained in abundance.

Nature and Deftnition.-As above stated, braxy is certainly not anthmx. Braxy has been known from earliest times in Iceland, while anthrax has been introduced, and apparently through the intermediation of imported skins, only quite recently. There is another disease, however, with which it has even closer points of resemblance, namely, quarter-evil (Rauschbrand). Quarter­evil is said tQ be unknown also in Iceland, and the two diseases, and the organism causing them, when compared, are readilv enough distinguishable. Thus braxy is never accompanied by any external lesion, as is the case in quarter-evil; it also runs a much more rapid course than that disease.

Braxy is, therefore, neither an anthracoid disease nor is it to be confounded 1 "'!Crans. 'Highland and Agric:.nlt. Soc.," July 1861-March 1863, p. 18. 2 Ib.d., July 1863-lIIarch 1860, p. 79. 3 "Urn bradasottina a Islandi og nokkur rad vid henni," 1876. 4 "Urn bradafarid i sandfe," 1873. B "Urn hradapestina og tilraunir til ad varna henni," 1876. 6 "Tidsskrift for Veterinaerer," 1888; also" Norsk Landsmandsblad," 1892; also "l\:Ionat­

shefte fiir prakt. Thierheilkunde," Bd. VIII. Hft. 2, 1896, p. 55. 7 "Principles and Practice of Veterinary Medicine," 1888, p. 304. 8 Some Blood Diseases of Sheep. "The Veterinarian," Vol. LXII. 1889, p. 892.

Deut. Ztschr. fiir Thiermedicin und vergleichende Path.," Vol. XXII. 1896, p. 249. 10 Vol. VIII. Hft. 4, 1896, p. 89; also Vol. IX. Hft. 2 and 3,1896, p. 33; also Vol. IX. Hft.

2 and 3, 1897, p. 77.

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with any other malady j it is a disease sui generis. The author's experience leads him to believe, notwithstanding all the varieties described from time to time, that, as in the case of anthrax, there is only one form which braxy assumes, and that the true point of diagnosis is the presence in the blood, liquids, organs, and tissues of the body of the characteristic organism.

Nielsen 1 has defined it as a gastromycosis, excited by a specific bacillus introduced with the food into the fourth or true stomach, and believes that the disease may either pass into a general affection, or may occasion the death of the animal through absorption of bacterial toxines formed by the organism germinating locally in a part. In these views he was supported by Jensen, who concluded as a result of the researches of previous investigators that bradsot is an acute, or even extremely acute, infectious disease which begins as a h~morrhagic inflammation of the mucosa of the fourth stomach, which is accompanied by the formation of gas in the alimentary canal, specially in the stomach, and which kills the animal in some cases by a general infection, in others apparently by toxic poisoning, or possibly in others still by dyspncea caused by tympanites. He held that the bacillus is introduced with the food, and that braxy thus differs materially from quarter­evil, which, according to Kitt's experience, he says, is seldom or never induced by administration of the organism by the mouth. He would also stigmatise the fourth stomach as the organ primarily and most severely affected. Too much emphasis has been placed upon the stomach lesion as an essential feature of the malady. In Professor Hamilton's experience the sloughy h~morrhagic patches found on the mucous membrane of the fourth stomach in some cases are completely absent in others, and the large inflammatory patches described as occurring on the outside of the rumen or other division of the stomach have nothing to do with inflammation; nor are they h~morr­hagic. They are simply part of the general blood-staining which ensues after death. No one, moreover, as Jensen himself confesses, has conferred braxy on the sheep or any other animal by feeding with the bacillus, and this result coincides with the author's own experiments. He has fed sheep on the blood, peritoneal liquid, and other liquids taken from animals dead of braxy, and which were teeming with the bacillus, and has never once succeeded in conveying the disease to the fresh host by this means, while the same liquids injected subcutaneously killed the animal in a few hours. Jensen gets over this difficulty by affirming that the herbage at the time braxy breaks out is cold, often of a rough nature, and a good part of it indigestible, and that this predisposes the animal to infection from the stomach.

The author thinks, however, that too much importance has also been attached to the lesion sometimes found in the stomach as evidence of the disease being communicated through that organ, for he has found in animals which died by the iRtroduction of the bacillus experimentally under the skin of the thigh, that sometimes the sloughs on the stomach were most typical. His impression is that it is a general disease, and that very soon after it is established the whole of the liquids, organs and tissues become more or less beset with the bacillus. He has never failed to find it, and in greater abundance than elsewhere, in the serous and blood-stained effusion into the peritoneum, and in that contained in the pleural cavities.

Sympto11ls.-Under natural circumstances the animal dies so rapidly that opportunity is seldom afforded of studying the disease from its commencement until its termination. All accounts, however, seem to agree that a short, quick step is perhaps the first sign noticeable. The animal is off its feed and is restless, with a tendency. to lie down and get up suddenly, as if expressive of a certain uneasiness. Quite likely 'it is noticed that it does not rise so readily to the dog as others do. When the disease has been conferred experi-

I "Mouatshefte flir praktische Thierheilkunde," Vol. VIII. Hft. 2, 1896, p. 58.

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mentally by inoculation upon a hind limb, the limb invariably hangs down in a paretic condition, the ankle is flexed, and the animal continues to roam about in a half-dazed condition, trailing the inol;;ulated limb after it. The pulse varies between 30 and 35 per minute, and is often imperceptible in the extremities, the breathing is somewhat laboured and from 40 to 42 per minute, while the temperature runs from 105 0 to 108

0 F. Rumination is entirely suspended, and a crunching noise is sometimes emitted. The belly usually begins to swell, the back rises, the head is depressed, and the animal roams about in a listless manner, then, probably, if not enclosed, will crawl away from its mates, take refuge in a cranny or nook, and finally falls over on its side. When this stage is reached, the latal issue is not far off. Probably within an hour or two the animal is dead. The blood is said to be very dark and thick and does not flow easily, but undue enlphasis has been laid on this as a symptom of the disease. When once the animal falls over it passes into a semi-comatose state, and makes no further effort to escape. It is often said that it seems to suffer from cramping pain in the abdomen, hut the author's own observation seems to point to the symptoms of uneasiness being due, quite as much at least, to feverishness and to the animal being in a half­delirious state. The swelling of the abdomen is often not at all marked until after death, when it ensues with great rapidity; a matter of a couple of hours being sufficient to render the abdomen tense and tympanitic. When inoculated experimentally, the subcutaneous areolar tissue of the thighs and abdomen can be felt to crackle on pressure at the time of death of the animal, and this also increases rapidly immediately after the animal has died. In some cases there is evidence of diarrhcea, and from the almost universally empty condition of the bowel after death, the author is inclined to believe that diarrhcea, or at least copious evacuation of the bowel, must be of common occurrence. The tail and the neighbourhood of the anus are frequently soiled with moist f::ecal matter. The urine is said to be scanty and dark-coloured, but he has not noticed, in cases where there was an absence of h::emorrhage into the muscles or elsewhere, that the urine contained in the bladder after death presented any abnormality.

The disease usually runs a course of from five to eighteen hours after the symptoms have declared themselves. The most rapid course noticed, in a case induced by inoculation, was nineteen hours, dating from the time the virus was introduced up to the fatal termination. Some cases are said to linger for a few days, but these are probably not instances of braxy. There is no more ~onstant sign of the disease than the extreme rapidity with which the fatal Issue ensues.

The incubation period, by inoculation experiments, was generally from forty· eight to sixty hours, but often very much shorter. When the virus is sporing and is injected simultaneously with acetic acid, not only does the attack prove more severe but the incubation period is diminished. '

Age of Ant111als Attacked.-Accounts of the disease from all countries seem to uphold the allegation that first year's animals are far more liable to braxy than those more mature. So long as the lamb is following the mother, it is seldom if ever attacked, but after weaning·time it is constantly liable to the malady, and this liability reaches its climax during the late autumn and early winter months. There is some endeavour on the part of flock-masters to show that if the hoggs are not separated from the mothers the disease is less severe than when they are kept in a hirsel by themselves, but the evidence is conflict­ing. Two-years' animals are seldom attacked in the West Highlands, and three­years' ewes are said to be quite exempt.

Tups do not seem to be attacked with the disease in the West Highlands, although they often suffer and die from a mysterious affection when brought from a distance and put upon fresh pasture. In a typical case of this tllp-

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disease, which the author examined both before and after death, there were not the usual signs of braxy, but in the liver there were patches of abscesses very like those associated with py<emia, and beset with filari<e. The animal seemed to have died from a septic<emia, taking its origin from this source.

Touching the question of the possibility of an animal in which the symp­toms are thoroughly established recovering, opinion seems to differ. Gamgee 1

never saw more than one or two cases in which recovery took place, even under the most approved methods of treatment, ana he is doubtful if those in which this favourable termination ensued were cases of true braxy. Neither in the natural disease, nor in instances where he has induced braxyexperimen­tally, has the author ever seen other than a fatal termination when the symp­toms were thoroughly developed. He has often seen an animal indisposed for a day or two after being inoculated, and recover completely; but the symptoms in such cases never amounted to more than trivial indisposition, characterised by a slight halt in the inoculated limb, elevation of temperature, together with some disinclination to feed. He has little doubt, however, that such animals were suffering from a mild attack of braxy, and in this sense recovery may be said to follow in a certain proportion of cases. In fact there is evidence to show that practically all sheep in infected districts take the disease, most of them in so mild a form as to render its detection difficult, and that possibly the future immunity enjoyed depends upon their having thus suffered.

Sporadic cases are said to occur during the summer months, but the great range of mortality prevails during the late autumn and eariy winter months. It may commence in September, or be delayed till the first or second week of November-a good deal,depending apparently on the advent of frosty weather. It disappears with quite as great irregularity-sometimes by the middle of December, at other times not until the end of February, The same peculiar­ity of advent and cessation of the disease has been noticed in all countries where braxy prevails.

Post-Mortem Appearances.-According to Jensen's description the following are the chief post-mortem appearances. When the animal is killed during an attack the essential change is a dark bluish-red, somewhat swollen patch on the fourth stomach. This patch increases in size, so that towards the end of the attack a great part or the whole of the stomach may be h<emorrhagic or serous-h<emorrhagic. The fourth stomach and adjacent part of the bowel are devoid of food, but sometimes contain a bloody fluid. The h<emorrhagic infiltration may spread from the fourth over the other stomachs, partly over the duodenum, or even over a great portion of the intestine, while other parts of the intestine may be h<emorrhagically injected. In the cavities of the body there may be a little serous fluid. The blood is dark, and may be clotted; and the spleen is occasionally somewhat swollen, but may be quite normal. The liver is pale, brittle, and degenerated, and in extreme cases the friability is probably from post-mortem causes. The kidneys may be normal or some­what degenerated; not uncommonly, however, they are enlarged and very brittle, or even diffluent. The cadaver decomposes very soon, and before long the hind-quarters become blown'up with gas, the verge of the anus pro­tuberant, the skin takes on here and there a bluis+t colour, and the wool is easily detached; sometimes the skin bursts and a serous-h<emorrhagic fluid is seen oozing from the subcutaneous areolar tissue.

In the case of sheep inoculated with a culture of braxy bacillus Professor Hamilton found that all showed a very marked h<emorrhagic subcutaneous cedema which spread out from the point of inoculation on the inner side of the thigh over the hindquarters and belly. In the musculature of the thigh and leg, partly in the abdominal muscles, there was widespread h<emorrhage,

t "Our Domestic Animals," Vol. III., p. 302.

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to such an extent that sometimes the muscles were quite black. Emphysema was also very evident in the muscles. Within the abdomen there was a little blood·stained liquid. The spleen, in all cases, was slightly enlarged, the liver yellow and degenerated, and the lungs very <:edematous. In one lamb the kidneys were soft and degenerated, while in other two they were almost diffluent, an appearance which he says is characteristic of spontaneous cases. On microscopic examination, great numbers of rods with round ends, and which were sporing, were found in the muscle juices.

In the cases examined by the author the bacillus of braxy was found widely spread abroad in the tissues and liquids of the body. The peritoneal liquid invariably swarmed with it, and it was also present in great abundance in that of the pleural cavities and subcutaneous areolar tissue. In the organs found altered after death, and which were examined microscopically, it was in great quantity. The blood contained it in varying amount. It seems to grow best, however, under natural conditions, in the various serous efftlsions, and par­ticularly well in the peritoneal liquid. Num~rous cul~ures were made from the peritoneal and other liquids derived from the above cases. They were inoculated successfully on fresh animals.

On microscopic examination of the fourth stomach, where diseased, he had always found the infiltrated patches to be free from any inflammatory indica­tiolls. The vessels of the sub-mucosa are distended with blood, and minute blood extravasations are present in the mucosa itself, but there is no effusion which can be termed inflammatory. The surface of the mucosa is necrotic, and most of the 'sloughy half-detached material evidently becomes digested off. The epithelium was always found to be destroyed by auto-digestion, while the necrosis of the surface extended into the glandular structure of the mucosa for perhaps a fourth of the thickness of the entire membrane. The blood corpuscles in the minute hremorrhages were always in a state of dissolu­tion, their presence being indicated by brownish pigment. The substance of the mucosa was swarming with the characteristic bacillus, sometimes extend­ing into the sub-mucosa and its blood vessels.

The lesions in typical cases are summarised as follows :-1. The absence of any external manifestation of the disease, as in the case

of the slough of quarter-evil. . 2. The tendency which there is, both during life and after death, to the

production of gas. 3. The presence of sero-sanguinolent effusions into the various cavities of

the body and into the subcutaneous areolar tissue. 4. The tendency to blood-staining of'the tissues. 5. The absence of inflammatory manifestations. 6. The occasional, but by no means invariable, hremorrhagic infiltration of

the mucous membrane of the fourth stomach, with, from time to time, ulcera­tion or digestion of the surface of the infiltrated parts.

7. The distension with lood of the first three stomachs, and the absence of food in the fourth or true stomach, and usually in the intestine. The presence of a little brownish-red grumous liquid in the fourth stomach.

8. The occurrence, occasionally, of hyperremia of the large vessels in the walls of this organ, accompanied by blood-staining of the surrounding tissues.

9· The absence of extensive hremorrhage into the musculature of the body; the absence of gas-production in the muscles.

10. The invariable presence of the braxy bacillus in the liqnids, tissues, and organs of the body.

The post-mortem appearances found in experimental cases corresponded essentially with those of the natural disease. There is the never-failing gas production and subcutaneous <:edema, the serous effusion into the various cavities of the body, the distension of the first three stomachs, the empty state

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of the fourth, and, usually, of most of the intestine. The occasional presence of ha:morrhagic infiltration of the mucosa of the fourth stomach with, it may be, ulceration or gangrene of the affected part, together with the presence oi the braxy bacillus in the effused liquids, the blood, and the tissues.

The only points of difference in the experimental cases, where the disease has been induce,d by subcutaneous inoculation, as compared with those which were spontaneous, are the presence of considerably mor!,! local emphysema and c.edema in the vicinity of the point of introduction of the virus, and also the tendency to extreme ha:morrhagic infiltration of the muscles opposite the point of inoculation. In both cases, that of the natural disease and that induced experimentally, there is an entire absence of phenomena which might be termed inflammatory, but there is a decided tendency to destruction of coloured blood corpuscles, the setting free of their pigment, and the staining therewith of the surrounding tissues.

TIle OrganislIl.-The merit of having thrown the first light upon the a:tiology of the disease is due to Ivar Nielsen. In his work on the subject,' published in the year 1888, he described an organism which he found in the ha:morrhagic areas of the digestive tract, as well as in the capillaries of the various organs, which is, without doubt, the essential factor in the disease. The organism in question is a rod from 2 to 6 p.. long or longer, and about IP.. in breadth, with rounded ends. It is sometimes found, in cultures at least, elongating into a thread, but, in the tissues, it usually takes the rod form. It retains the stain by Gram's method, and more readily when quite freshly removed from the body; it is perfectly immobile, both when taken immediately from the various serous effusions or the blood and when in culture. As it occurs in the various liquids of the animal, it has a great tendency to spore, often nearly every rod being in this condition. The spore is usually placed at one end of the rod, and when developing gives to this end merely an appearance of being thicker than the other, while, with careful focussing, a clear, minute, and highly refractile point may be detected in the midst of the tuberosity. As the spore enlarges it becomes more and more refractile, and takes on an elongated oval shape, and in this stage the organism has a characteristic drumstick appearance very like that of tetanus. Sometimes the spore is located in the middle of the rod, and occasionally a couple of spores of large size are seen in a single bacillus, one at each end. The individual bacilli may be either united at an angle when in juxtaposition, or their axes may lie parallel and in line, in which case they may resemble a single bacillus of unusually great length. Exceptionally they may hang in rows, but this is not common. In certain instances of the disease the spores are present only in small number,' or may even be absent, and in such cases the virus appears to confer a mild attack. At any rate, Professor Hamilton has often found difficulty in inocula­ting the disease and producmg a fatal issue when the organism is in this non­sporing condition.

It seems to be a strict ana:robe, at least when first removed from its natural habitat. It is extremely difficult to isolate by means of plate cultures if there be the slightest trace of oxygen in the surrounding atmosphere. The method which, in the author's hands, has proved most successful, is the following: Take the virus from a case in which the organism is sporing profusely. Use a medium composed of peptonised beef-tea with 2 per cent. glucose, and be careful that the medium has a faint, but a quite decided, aCId reaction to litmus. Boil the medium for half an hour before inoculating it, and while it is boiling, or as soon as possible afterwards, inoculate it with a couple of osefuls of some of the serous effusions of the body, preferably the peritoneal liquid. The chief organ of contamination is Bacillus coli, and this is killed off by the high tem­perature of the medium. Close the mouth of the tube immediately thereafter

1 "Bradsot hos Faret (Gastromycosis ovis) Tidsskrift for Veterinaerer, " 1888.

188 REPORTS.

with a well-fitting caoutchouc cap, and keep the medium at a temperature of 3f C.Within a few hours gas begins to be given off copiously, which escapes between the cap and the side of the tube, while the cap contracting makes an excellent valve. At the end of forty-eight hours gas formation has ceased, and the organism falls down, in the shape of a fine greyish-coloured precipitate, to the bottom of the tube, or, if the tube has been in a sloping position, adheres to the lowest side. It seems to grow comparatively little after the time when gas ceases to be evolved, and from this time onwards will generally be found to be sporing.

Other media can be employed for its culture, but in none of them is the appearance of the growth so characteristic as in the above. Thus it will grow in agar or serum-agar readily enough, the growth in agar being, however, slower than in other media. The addition of 2 per cent. glucose to any of these media increases their usefulness. Gelatine is not a favourable medium, although the organism will grow in it.

Where inoculated pure in glucose-agar a luxuriant growth rapidly shows itself along the track of the needle up to within I to I~ c. from the surface. There is never a particle of growth on the free surface if the atmosphere within the tube contains oxygen. Copious gas-bells are given off, which soon tear the medium in pieces and force it up against the cottonwool plug. If the disengagement of gas is slight, mere slits or tiny rents may be formed in the medium, along which the bacillus tends to propagate.

For inoculation purposes the organism taken from the peritoneal liquid is the best to work with, grown in glucose beef-tea as above described. By the end of forty-eight hours the growth is in the best condition for inoculating. At a later period, and in proportion apparently with the time, the virulence of the organism becomes less and less j but a good deal seems, as with other bacteria, to depend upon whether it is sporing or not. The spores are peculiarly tenacious of life. Thus Jensen found that after the stomach of a braxy sheep had been kept in dilute spirit, even for a period of seven weeks, he was still able to get a growth from it.

The organism of braxy is apparently very closely related to that of quarter­evil and of malignant <:edema. The three form a group which stand isolated, and which have intimate mutual relationships. In fact, when growing in solid media there is much difficulty in distinguishing them. Its complete immo­bility seems to be one of the best features hy which the braxy bacillus can be distinguished from the other two. According to Jensen, the braxy bacillus is also to be distinguished from that of quarter-evil by the fact that it is patho­genic to mice, pigeons, fowls, and pigs, animals which are insusceptible to quarter-evil. It is a remarkable fact, however, that these animals never take the disease naturally, nor has the disease ever been known to affect the cow, the dog, or man. The sheep seems to be the only animal which is naturally subject to it.

Immunity of certain Sheep.-From the partial distribution of the malady it would seem that there must be something peculiar either in the virulence of the bacillus in different districts, or in the susceptibility of the sheep reared upon them. Aberdeenshire and Forfarshire enjoy such immunity that they are the great wintering-grounds of hoggs from the West Highlands. Native sheep in Iceland, the Faroes, and Shetland seem to be much less liable to the disease than those which are imported. If sheep of a breed naturally susceptible are brought from a distance and pastured on braxy land they almost invariably fall victims to the disease in large numbers. There are some curious exceptions to this rule, however, and none more so than in the case of sheep reared in Aberdeenshire.

At the commencement of the inquiry the author brought home with him time after time blood, serous liquid, and organs from typical cases of the

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disease met with in the West Highlands. These were inoculated subcut­aneously forthwith on Aberdeenshire hoggs, but always without positive result. Cultures were made from them and inoculated in the same way, but still with the same negative effect. Through the kindness of Dr MaIm, Director of the Civil Veterinary Institute in Christiania, he obtained some powder of a desiccated liver from a braxy sheep which died in Iceland, together with cedema liquid and blood from a sheep inoculated with Norwegian, braxy, and which died from it. These were inoculated into Aberdeenshire hoggs, but still without conferring the disease upon them or causing much constitutional disturbance. The animals employed came from near the coast close by Aberdeen.

Under these circumstances he began to suspect that there was something peculiar about Aberdeenshire sheep which rendered them less susceptible to braxy than those reared on the West coast. The animals he employed were at first blackfaces, but he tried the experiment with a Cheviot and a cross without conferring the disease upon them. He rt;solved, therefore, to make his next experiments in the West Highlands in order to test the above suspicion.

In the month of January, accordingly, he inoculated a West Highland, blackfaced hogg, in the neighbourhood of Corpach, with peritoneal liquid taken from an animal just dead of the disease. The animal inoculated died from typical braxy in the specified time, with emphysema and h<emorrhage spreading up over the limb and posterior part of the body, from the point of inoculation. The same virus taken home and inoculated on an Aberdeen­shire hogg proved negative.

In January of the year 1901 he took six blackfaced Aberdeenshire hoggs up to Corpach, and placed them on ground notorious for braxy. The farmers in the heighbourhood told him that before long they probably would all die from the disease; such an unheard - of proceeding was to their minds practically certain to have only one result, and that a fatal one. An animal happened to die from braxy on the farm where they were pastured, a few days after their arrival, and he obtained a quantity of peritoneal liquid from its abdomen. The following day 3 cc. of this liquid were mixed with 30 cc. of neutral beef·tea, and I! cc. of this was injected subcutaneously into the right thigh of these six hoggs. The same quantity was similarly injected into the right thigh of each of six other blackfaced hoggs which had been born and brought up on the farm. The twelve animals were placed in an enclosed field side by side and under exactly the same conditions. Within forty-eight hours, one of the native sheep was noticed to be ill: the inoculated leg hung down, and the animal was in a listless, dazed condition. It died with typical braxy a few hours afterwards. Another of the same lot was noticed to be somewhat dull, but ultimately recovered. None of the Aberdeenshire hoggs showed the slightest symptom of illness.

The virus in this case must have been of a mild form, and probably this accounted for so many having escaped; but evidently the Aberdeenshire sheep were less susceptible to it than those reared on the West coast-for not only were they placed under the most disadvantageous circumstances, being moved from one district to another, but they were actually inoculated with the virus from a dead animal.

Probably Aberdeenshire sheep take a mild attack of the disease in the autumn or early winter which renders them immune. The following observa­tion seems to support that view. Two blackfaced Aberdeenshire lambs were inoculated with ,the same virus used in the experiment just quoted, but at the end of August instead of the beginning of January. One of them died within forty-eight hours with all the signs and symptoms of braxy, and its body was found to be swarming with the bacillus. This lamb was evidently not

REPORTS.

immune, and possibly the reason of this was to be found in its not having suffered as yet from the disease.

It seems very likely also that the bacillus gains in virulence by being passed. through the system of the sheep. Thus the organism in the peritoneal liquid from the last-mentioned sheep was grown for two days in glucose beef-tea in a pure state. The culture was inoculated during the month of February into the right thigh of six Aberdeenshire hoggs. Within forty-elght hours, one of the six hart died from braxy and two others succumbed in a few days after­wards. This was an experience the author has never had before with Aberdeenshire sheep, and he thinks that it may be explained by the excessive virulence of the organism, due to its having passed through the system of three animals. He never saw the organism so actively engaged in sporing as in this l'>articular virus.

It would even seem that it gains in virulence by being passed through the system of the guinea-pig. With a particular virus, on one occasion, he endeavoured repeatedly, but in vain, to inoculate an Aberdeenshire hogg. The same virus was passed in succession through the abdomen of three guinea-pigs, and was thereafter again inoculated into ' the thigh of the same hogg. It died within the usual time, with eroded h;emorrhagic patches in the fourth stomach, and its tissues and blood pervaded with the typical bacillus.

It is well-known that the subcutaneous injection of acetic acid simul­taneously with the bacillus of quarter-evil in a state of attenuation, has the property of restoring that organism to its original virulence. The author's experiments with attenuated braxy bacillus seem to demonstrate the ·same fact . The most severe case of experimental braxy which he witnessed was one in which acetic acid was injected into ' the right thigh, an attenuated ' peritoneal liquid into the left.

Introduction oj the Poison into the System ojt/le Sheep.-Jensen upholds the view that it is ingested with the food, but against this theory is the fact that no one has ever induced braxy by administration per os. It seems unlikely that the tick plays an active part as intermediary host. Brazy does not occur at a time when ticks are prevalent, and frosty weather has been proved to cause the tick to pass into a torpid condition. The author is convinced that the one means of generating and spreading braxy is fouling of the ground from the carcases and various excreta of animals dying of the disease. The spores of braxy are very resistant to various extraneous agencies, and it only stands to reason, if myriads of these spores are left in the soil from a carcase, of are blown about in the form of dust, that, sooner or later, they will find their way into the bodies of sheep feeding on the infected pastures.

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