Chapter XV: Agriculture; Horses; Cattle

_Agriculture_

(1) _Labourers._--The manifold occupations included under the general term of tilling the soil, exercises a beneficial effect on the husbandman as regards mere length of days, for he often lives far beyond the allotted span, although he rarely comes to the end of his career a hale and hearty old man. His operations are carried out for the most part in the open air, leisurely, and in a greater or less degree of isolation. His condition, therefore, has its drawbacks as well as its advantages. As one of the oldest occupations of mankind it has been very largely adopted as a means of gaining a livelihood, and, until recently, the supply of farm labourers has exceeded the demand. It is badly paid; the farmer, at least in England, has many anxieties, disappointments and losses in his crops and stock; the labourer receives but small wages, and has perforce to put up with scanty living and poor accommodation. The living is made worse by the ignorance of cooking and domestic economy, which is so general amongst the wives and daughters of the labouring class. Field work begins early in the morning, and leads to exposure in all weathers. It is usually so monotonous, that it is unattractive to the better intellects amongst the lower orders; it is sometimes very hard, as during hay-making and harvest, and it is occasionally dangerous, as in hedging and ditching.

“Rheumatic” affections are foremost amongst the bodily ills of field workers, not often as acute rheumatism, but rather in some of the protean forms which affect the connective tissues. Osteo-arthritis, sciatica, lumbago, and valvular heart lesions are commonly met with. Indeed, the rheumatic affections of old age have been known for so long a time that Scapula, in his great lexicon, says, with doubtful, though picturesque, etymology, “Γέρων, the Greek word for an old man, has been derived by some παρὰ τὸ εἰς γῆν ὁρᾷν, because old men by their stooping look towards the earth; though others, with more probability, derive it from the same stem as Γέρας, on account of the reverence due to age.” The etymology, whether right or wrong, draws attention to the stooping habit which is typically a senile kyphosis, though it is accentuated by occupation, and is found early in middle life in agricultural labourers, as often as in tailors, cobblers, clerks, Swiss mountain porters, and, latterly, in some bicyclists. True senile kyphosis or stooping arises from simple weakness and wasting of the tissues, with absorption of the intervertebral discs, and is not necessarily due to rheumatism. But amongst agricultural labourers, it is usually associated with osteoarthritic changes, which tend to unite the individual vertebræ by bridges of bone, whilst it thickens the spines and hardens the ligaments. The stage of anchylosis is often preceded by a period of inflammatory softening, which leads to more or less deformity of the vertebral column, for lateral curvature is nearly as common as the forward stoop to which the name kyphosis is given.

The same factors of hard manual labour, often in constrained attitudes and under unfavourable conditions of weather, produce other “rheumatic” affections, such as pains in the limbs, aching in the bones and stiffness in the joints, which disturb the comfort without lessening materially the wage-earning power of the rural population. No one can have attended the local fair or feast without noticing the peculiar shuffling walk, and the knock-knee of the ploughboy, the results respectively of flatfoot and over-growth, aided by badly fitting, uncouth boots, and a habit of walking over uneven surfaces.

The palmar fascia of the hand often becomes contracted--Dupuytren’s contraction--a condition whose cause is unknown, though it has been variously attributed to such predisposing causes as gout and rheumatism, or to habits and occupations necessitating pressure in the palm and flexion of the fingers, as in digging. The contraction usually begins in that portion of the fascia which is continued on to the sheath of the flexor tendon of the little finger, afterwards attacking the portion extending to the ring finger, and sometimes the remaining fingers. The fingers are thereby flexed and drawn down towards the palm, with which they may even be fixed in contact. This form of contraction may be distinguished from that due to a contracted tendon, by the puckering of the skin in consequence of its adhesion to the fascia, and by the contracting band bifurcating to be inserted upon either side of the flexor tendon, whilst the contracted tendon is placed centrally, and can be traced under the annular ligament.

The kindness of the late Dr Tinley, and Dr Granger at Whitby, and of my brother-in-law Mr G. H. Fosbroke, the County Medical Officer of Worcestershire, has lately allowed me to examine the death returns of two typically rural districts. The chief causes of death are bronchitis, including pneumonia and pleurisy; heart disease, a very vague term covering a multitude of pathological conditions; and phthisis. The deaths from bronchitis and heart disease, in a period of ten years, are nearly equal in number, whilst those from phthisis were only half as many as either of the other two.

Typhoid fever is endemic in many districts, owing to the improper disposal of excrement, and from the use of polluted water in surface wells.

Some of the older countrymen living in the fen districts east of Cambridge still take opium regularly to keep off ague, and I have a working hypothesis that these same dwellers in districts which were once highly malarious are now more subject to cancer than persons who live in towns where the soil is drier and insects are fewer. Be this as it may, however, gardeners and those who have to handle soot in the course of their work are liable to develop epitheliomatous ulcers of the hand and wrist more often than those who are free from such source of local irritation.

Lunacy is increasing markedly amongst the rural population in some parts of the country, and notably in Ireland. This is probably due to the tide of emigration carrying away the more highly endowed and enterprising, whilst it leaves the old and those who are enfeebled in body and mind.

Agricultural labourers do not, on the whole, fare very badly. Even with low wages and bad sanitary surroundings, the social condition of the English farm hand compares most favourably with that of the peasantry in many European countries. The absence of the three great diseases epidemic amongst those who are reduced to the lowest depths of misery by chronic starvation, is a proof of this superior position. The three diseases are ergotism from the use of spurred rye; pellagra due to bad maize; and lathyrism caused by the consumption of the chick-pea.

Ergotism is rife amongst the rye-eating inhabitants of Germany, Bohemia, Sweden, Russia, and the central provinces of France. It occurs especially after rainy seasons, and the bread made from the diseased rye is violet in colour, and of a disagreeable taste and smell. It is usually badly made and badly baked. The symptoms of ergot poisoning are either acute or chronic. The acute form begins with giddiness, headache, lassitude, and disturbances of sight and hearing, which have led to its being called “ergot intoxication.” The chronic poisoning is ushered in with symptoms of ergot intoxication, but the later stages are either convulsive or gangrenous. The convulsive form is marked by intermittent clonic spasms of the limbs, with dilatation of the pupil, delirium, and coma, which soon ends in death, without any appearance of gangrene. The mortification in the gangrenous form is preceded by pain in the part, with intolerable “creeping” feelings, followed by diminished sensibility, which ends in dry gangrene, and finally in separation of the affected tissues. The patients suffer occasionally from vomiting of blood, or from passing blood in the urine, the bleeding being as difficult to arrest as in hæmophilia.

Pellagra from the consumption of bad maize, truly known as the _malattia della miseria_, is epidemic in parts of France, Spain, Italy, Africa, and Brazil. It requires for its full manifestation a most wretched peasantry. Pellagra is characterised by headache, depression of spirits, sleeplessness, cramps, palsies, giddiness, and dyspepsia. There are vague but often severe pains in the spine and joints, and there is a skin eruption, which begins in April or May, and goes from bad to worse, until it begins to improve in July or August. The eruption is an erythema of the parts exposed to the sun. The skin becomes swollen and tense, with petechiæ and bullæ, which leave indolent ulcers when they break. The attacks recur in the spring of each year, until in time the skin becomes thickened and of a light sepia colour. The nervous symptoms culminate in a settled melancholia. The spinal cord appears to be definitely affected both in ergotism and pellagra, the posterior columns suffering chiefly in ergot poisoning, the lateral columns in pellagra.

Lathyrism results from the use of the chick-pea (_Lathyrus sativus_, _cicer_, or _clymenum_) as an article of diet. Like ergotism and pellagra, it is associated with extremely wretched conditions of life, and has been observed in France, in the Abruzzi, at Allahabad, and in other parts of India. Oxen, horses, pigs, and geese are attacked as well as men. The symptoms point to an affection of the lower part of the spinal cord, and are manifested by a sudden inability to use the legs in the ordinary manner. The legs are so stiff that when the patient walks he is obliged to throw his body into a succession of curves, so that he describes a screw or figure of eight as he proceeds. There is much hyperæsthesia of the lower extremities, which may be followed by loss of sensation, though the patient complains of the same tingling sensations as are felt in ergotism. The onset is usually sudden, and is coincident with the advent of cold weather, but the symptoms take four or five weeks to reach a maximum.

The increasing use of machinery in ploughing, reaping, threshing, and other farming operations leads necessarily to a greater number of machine accidents than was formerly the case when labour was abundant and machines were few. Even small farmers now possess a chaff-cutter, and injuries to the hands and arms produced by its cog-wheels are correspondingly frequent. Much more serious injuries are caused by the large threshing and reaping machines, which are sometimes tended by unskilled persons, as they are often let out on hire. Overstrain from the lifting of loads in awkward positions during harvest is no uncommon cause of hernia in those who are otherwise predisposed to this condition. Poisoned wounds of the hand, and penetrating wounds of the eye, are often sustained in the occupation of hedging and ditching, a form of labour which is also the cause of rheumatism. Occasionally, too, an agricultural labourer presents himself with a viper bite, for vipers are still indigenous in several parts of England. He complains of a burning pain at the part bitten, the limb swells and becomes discoloured within an hour or two, there is great prostration marked by sweating, vomiting, feeble pulse, and restlessness. The more acute symptoms usually pass off in the course of twelve to twenty-four hours, but in unhealthy persons the swelling increases; there may be suppuration, and the bite then ends in a severe attack of inflammation of the tissues, known as cellulitis.

In like manner stings from bees, wasps, hornets, and gnats, which are usually of small importance, may become serious, either from the bad condition of the patient’s health, or from the position of the sting, as when the mouth or conjunctiva is affected. A tolerance is established for bee-stings and gnat-bites, as is shown by the very slight reaction which takes place in bee-keepers and the inhabitants of mosquito countries, as compared with the sufferings of a town-bred man who is stung by either of these insects.

In mushroom-poisoning the poisonous constituent is muscarin, a nitrogenous body allied to cholin. It causes vomiting, diarrhœa, and prostration, with convulsions and contraction of the pupil. Death may occur from syncope and failure of respiration, but such an ending is rare, except in children, because the vomiting promotes the evacuation of the poison. Atropin is the physiological antidote, and a subcutaneous injection of as much as ¹⁄₃₀ to ¹⁄₁₆ of a grain may be given hypodermically, whilst diffusible stimulants are administered by the mouth.

(2) _Gardeners_ appear to suffer from many of the affections common to farm-labourers, except that as they receive higher wages they are better clothed, better fed, and better housed, and are thus able to withstand climatic changes more successfully. It is said, on the other hand, that gardeners are somewhat more liable to phthisis. Their work in hothouses causes them to catch cold more easily, and may thus increase any predisposition to infection by the tubercle bacillus. The handling of such plants as the _Primula obconica_ sometimes produces a very troublesome erythema of the skin, whilst constant contact with fresh soil allows greater opportunities of contracting tetanus.

The Museum of St Bartholomew’s Hospital contains an interesting specimen, showing that the epitheliomatous form of cancer sometimes follows the irritation produced by gardening. The specimen consists of the hand and part of the forearm removed on account of a growth covering nearly half the surface of the skin. The growth is warty, very vascular, superficially ulcerated, and with an everted sinuous edge. It bears a close resemblance to an ulcerated cancer of the scrotum in chimney sweepers. The patient was forty-nine years old. Five years before the amputation of his hand he was employed as a gardener in strewing soot over the ground for several mornings in succession; a warty growth then formed, and it increased and ulcerated in the spring of both the following years, whilst he was similarly employed. After this, though he was no longer in contact with soot, the disease increased until the limb was removed. He recovered completely after the operation. The case is related by Sir James Earle in his edition of Percivall Pott’s works.

Dupuytren’s contraction of the palmar fascia is by no means uncommon in gouty and rheumatic gardeners as they become advanced in years. It is best treated by dissecting out the contracted bands, if this can be done without suppuration, the resulting scar being afterwards kept supple by daily massage.

_Horses._

(3) _Ostlers, Stablemen, and Cartmen._--This class of men, from their close attendance in stables, necessarily contract the diseases which are transmissible from horses to ourselves. Foremost amongst these diseases are glanders and farcy, of which I have seen several cases in veterinary students; and tetanus, whose bacillus is said to live in the horse’s intestines.

Glanders, in its acute or generalised pyæmic form known as farcy, attacks grooms, ostlers, coachmen, knackers, and veterinary surgeons, because they are brought into contact with diseased animals. It has also been seen as a result of accidental infection in the pathological laboratory during the preparation of mallein; in surgeons who have operated upon glandered patients, and even in washerwomen who have washed the clothes of those affected.

Glanders occurs in an acute form which kills in eight to fifteen days, and a chronic form said to last as long as eleven years.

Acute glanders in man has an incubation period of three to eight days, though the symptoms are occasionally delayed for three weeks, or they may appear within twenty-four hours, and suppuration may occur at the end of the second day. The patient complains of a general feeling of ill-health with headache, and such vague pains in the muscles and joints as lead him to think that he is about to have acute rheumatism. The symptoms increase in severity, and there is often sufficient gastro-intestinal disturbance associated with deafness and stupor to lead to an erroneous diagnosis of typhoid fever. The pulse is full and soft, beating 90 to 100 in a minute; the skin is dry; the mouth foul, and epistaxis is frequent. Swellings--“the farcy buds”--soon appear in the intermuscular planes near the joints on both sides of the body. The swellings are at first hard, but they quickly soften, point, burst, and leave large foul ulcers, which eventually contract into sinuses if the patient survive. The case may then be looked upon as one of chronic pyæmia, especially as rigors are numerous and severe, but all doubt as to the true nature of the disease is set at rest when the face becomes affected. The skin over the nose is reddened and swollen, whilst the mucous membrane is injected and discharges a fœtid secretion, clear at first, but soon becoming yellow, purulent, viscid, and finally blood-stained. Ulceration of the nasal mucous membrane occurs less frequently in man than in the horse. The conjunctivæ are often affected in a manner similar to the nasal mucous membrane, and the inflammatory condition spreads to the pharynx, palate, and glottis. Dyspnœa, with pleuritic pain, may be a marked symptom of the disease, extensive gangrene may occur, and death follows.

Glanders is generally inoculated through a wound or abrasion, but the bacilli are able to penetrate to the uninjured lymphatics of the skin by way of the hair follicles, and in the case of two veterinary students who have been under my care the infection was directly traceable to their being sneezed over by a glandered horse they were examining. If a wound be the seat of infection it may heal, but in a day or two it becomes swollen and painful, an eruption of vesicles often appears round it, and the lymphatics become swollen and painful, though the glands are rarely affected. The skin, in some cases of farcy, shows erythematous patches like those of erysipelas or erythema nodosum. The patches become pustular or phlyctenular, or a pustular rash without umbilication may first be noticed. The latter form of rash is said to be of very grave significance, for recovery seldom if ever takes place when it makes its appearance.

Glanders affects many animals besides horses, mules, and donkeys. It has been seen in lions, leopards, tigers, and bears in various menageries; field-mice, guinea-pigs, and hedgehogs are highly susceptible. Infection may result not only from direct contact with the sick animal and its nasal discharge, but also from the pus, saliva, and milk. Food and drink may convey bacilli directly into the alimentary canal, which is thus affected primarily, the nasal mucous membrane becoming involved as part of a secondary process.

Chronic glanders may last for years, the patient suffering from acute but intermittent attacks of fever, in one of which he may die, or from which he may wholly recover. The skin in these cases is often the part chiefly affected. It becomes swollen and œdematous, with nodules, which only appear in one part and break down into indolent ulcers. The ulcers heal and leave scars which, with the destruction of the septum of the nose and the ulceration of the pharynx and soft palate, sometimes raise a suspicion of syphilis.

The disease depends upon the presence of the bacillus mallei and the toxic substances produced during its growth. The bacillus may be isolated from the abscesses, blood, enlarged skin follicles, and the ulcers. They are more easily recognised in properly stained “smear preparations” than in sections, and are readily cultivated in three to five days on acid potato media at a temperature of 35° to 37° C. as a brownish, moderately thick and opaque growth. The active principle of the growth is “mallein,” which can be obtained as a syrupy fluid. Mallein injected into a glandered animal produces an inflammatory swelling at the seat of inoculation. The tumour is tense, painful, and very extensive. The lymphatics from the seat of inoculation to the neighbouring lymphatic glands become inflamed, and are painful, swollen, and sinuous. The local tumour increases in size for twenty-four to thirty-six hours, but does not suppurate unless septic organisms have been introduced at the time of the inoculation. It subsides slowly in eight to ten days. Inoculation is followed by a general reaction, which appears within eight hours of the time of injection, reaches a maximum in ten to twelve hours, and lasts twenty-four hours. The animal shivers and sometimes has well-marked convulsions. The test is a very valuable one for latent glanders in horses, and as mallein diluted with ten times its volume of a ½ per cent. solution of carbolic acid preserves its qualities unimpaired for many months, it is now largely used in all parts of the world. A healthy horse either does not respond at all to a much larger dose of mallein than will affect a sick animal, or else a small swelling appears at the seat of inoculation, which only lasts for twenty-four hours. Glandered men, in the few cases where it has been employed, show the same reaction to mallein as glandered horses. The Straus test is also valuable in the diagnosis of glanders. It consists in diluting the suspected secretion with sterile water, which is then injected into the peritoneal cavity, and beneath the skin of male guinea-pigs. The testes appear to swell two or three days after the injection, and the animal dies in four to fifteen days with acute inflammation of the tunica vaginalis, the testicles and epididymis being only rarely affected.

Acute farcy is very fatal, but 50 to 60 per cent. of the patients affected with chronic farcy recover. The treatment at present is most unsatisfactory. Stimulants and tonics must be given liberally. Every abscess must be opened and disinfected as soon as possible, and benzoate of soda may be administered in drachm doses three or four times a day. In chronic cases marked improvement is said to have taken place after the continued injection of mallein in doses of ¹⁄₂₀ to ¹⁄₁₅ c.c. at intervals of two or three days.

Tetanus, often called lockjaw, is due to the poison produced by certain bacilli, which were first isolated by Kitasato, Tizzoni, and Cattani, in 1889. The micro-organisms are delicate threads with somewhat rounded ends, which reproduce by sporing. When the bacilli are about to spore one end becomes enlarged, and the organism resembles a pin or a drumstick. The spores are extremely tenacious of life, they resist the effect of high temperatures for an unusual length of time, they survive a temporary immersion in strong antiseptic solutions, and they have been known to retain their vitality for more than twelve months if they are protected from light and air. The parent bacilli are widely distributed in garden earth, in dust, and in the excrement of animals, especially in those of the horse, for this animal seems to be their natural host. They have been found, therefore, in stables and in manured fields, and they have the power of growing outside the body.

During their growth the bacilli produce a powerful poison, which is formed so slowly that it may take two or three weeks to produce its full effects. This poison is formed at the seat of inoculation, for the bacilli do not seem to travel far from the place where they are introduced, and it is generated more rapidly and abundantly in suppurating than in aseptic wounds. It produces its effect by a definite action upon the nervous system, and probably travels through the circulation, though there is still some doubt whether it does not reach the spinal cord by way of the nerves, so definite are some of its early effects. Tetanic symptoms can be produced by the inoculation of toxins, which have been purified of bacilli, and mice appear to be especially susceptible to the disease thus produced.

It will be clear from what has been said that tetanus is by no means rare. It may ensue from a wound at any part of the body, the wound varying in severity from a total crush to a slight abrasion which has passed unnoticed, and the case is then looked upon as one of spontaneous origin. It is especially frequent after injuries of parts which are usually dirty, and is consequently somewhat more common after wounds of the hands and feet. Though gardeners, horse keepers, and agricultural labourers often suffer, I have repeatedly seen cases in people who have been run over, and inoculated with the foul mud of an ill-kept London street. Horses, sheep, and cattle are also liable to infection. But on the whole tetanus has become less frequent, since an attempt has been made to keep wounds aseptic, or at any rate to shorten the process of suppuration.

The onset of the disease is usually marked by a feeling of general uneasiness and depression, unless the wound is too severe to allow of this manifestation. The first symptoms usually consist of a feeling of stiffness or soreness about the jaws and throat, with some tonic contraction of the platysma-myoides, causing the _risus sardonicus_, which is particularly well marked when the patient is asked to protrude the tongue. Spasms of greater or less severity then occur in the voluntary muscles, the pain varying greatly in different patients, though it is usually less than that of ordinary cramp. The muscles, especially those of the abdominal wall, are in a state of persistent tension in the intervals between the attacks, the tension being reduced to a minimum during sleep or anæsthesia produced by artificial means. The intellect remains undisturbed unless there is much fever. Death takes place from exhaustion as early as the third day in acute cases, but it is often postponed for a fortnight or three weeks.

The prognosis seems to vary with the rapidity of onset, for the mortality is great when the incubation is under ten days, whilst nearly half the patients recover if the symptoms do not appear for more than a fortnight after the injury.

The treatment is largely prophylactic. A wound contracted under suspicious circumstances, as when other cases of tetanus have occurred in the same village or stable, should be immediately rendered aseptic by a process of thorough cleansing. This is preferable to the use of the actual cautery, which leads to suppuration, and thus tends to increase the growth of the bacillus. When the initial symptoms appear, the injured part must be removed, as the wound is a local factory for the production of the nerve poison. Doses of antitoxin must be administered by hypodermic injection, and I prefer to do this by injecting it deeply into the gluteal muscles rather than into the brain or subarachnoid space, as is now the custom. The maximum dose of Tizzoni’s antitoxin is 40 c.c., which is equivalent to 2,500,000 units. This large dose may be given at once, 5 c.c. injections being afterwards given two or three times a day until the tonic contraction of the muscles has disappeared. The antitoxin appears to cure the slighter cases, and it produces a temporary relief in the most severe, but all the severe cases I have seen have died in spite of treatment.

Hydrophobia, the rabies of animals, is another form of poison acting upon the spinal cord, to which huntsmen and stablemen are peculiarly liable from the nature of their occupations. The pathology of the disease, however, is much less clearly understood than in the case of tetanus. Dogs, foxes, wolves, and cats; horses, cows, and deer, may contract rabies and transmit it to man by the saliva, or more rarely by the milk; whilst monkeys, rabbits, and guinea-pigs are susceptible to infection. The latent period appears to vary enormously, as its limits have been given as fourteen days to five years, though the ordinary incubation period seems to be from three to six weeks, the length of time depending upon the ease with which the poison reaches the nerve sheaths, and passes along them to the nerve centres in the medulla and upper part of the spinal cord. There is no doubt, however, that the poison of rabies can be absorbed from the uninjured mucous membranes of the body, especially from the conjunctivæ and the nasal mucous membrane.

In the cases which I have seen the symptoms have been preceded by two or three days of mental agitation and apprehension without apparent cause. Hiccough and difficulty in swallowing were the earliest signs of the disease, and these slight symptoms of undue reflex irritability gradually increased until the whole body became convulsed, the patient’s sufferings being increased by the viscid saliva, which he has attempted in vain to expectorate. Death took place suddenly either from cardiac failure or from spasm of the glottis.

The Pasteur treatment offers the best chance of a cure to a person who has been inoculated with rabies. Its success depends upon the fact that the spinal cord of a rabbit dying of rabies contains the poison, which becomes progressively less virulent after death, if the cord be protected from decomposition by exposure to pure dry air, until on the fifteenth day it is harmless, and a solution of the cord may be injected into a susceptible animal without producing any effect. Successive inoculations of an animal already infected show that it is possible to establish a condition of complete tolerance, even for a strong dose of the poison previously introduced, though the process of inoculation has not been begun until five days or longer after the bite. The Pasteur treatment at the present time consists of a series of simple inoculations lasting fifteen days, during which emulsions from cords of fourteen to three days’ desiccation are injected in doses of 3 to 2 c.c. at a time under the skin of the abdomen. There is also an “intensive” method, for more serious cases, such as the bite of a mad wolf, or when the wounds have been on the face. In this method the number of injections which are usually spread over five days is compressed into three days, the whole duration of the treatment being twenty-one days, a fresh series of injections being recommenced on the fourteenth day. Certain modifications of Pasteur’s method have been adopted, notably the use of an antirabic serum from the dog, prepared by Babes of Bucharest, and an attenuated vaccine by a process of peptic digestion, recommended by Tizzoni and Centanni.

As anthrax or charbon, sometimes known as splenic fever or malignant pustule, is considered elsewhere in this work, it is only necessary to state that the disease is due to the _Bacillus anthracis_, which is readily communicated from domestic animals to man. It is met with in the following classes: (1) those who come into contact with living animals suffering from anthrax, as drovers, shepherds, farmers, farriers, and veterinary surgeons; (2) those who touch the carcasses of animals that have died of anthrax, as knackers, slaughterers, and others; (3) those who handle the offal, skins, hoofs, horns, hair, wools, and other derivatives from such diseased animals, as tanners, fell-mongers, wool-workers, hair-workers, horn-workers, rag-sorters, plasterers, furriers, felt-workers, brush-workers, mattress-makers, and so forth; (4) in those who have a less direct connection with infective materials; as, for instance, those who live in the neighbourhood of such manufactories or occupations, for the disease may be carried by animals and insects; (5) anthrax has been transmitted from person to person by accidental contact, and may be contracted at a post-mortem examination upon a patient or animal who has died of the disease. There is some reason for supposing that small meat-eaters are more susceptible to anthrax than those who are accustomed to much animal food.

Influenza has long been known to occur in horses, and in several epidemics the disease has been observed to spread from these animals to their attendants. Mr Youatt first pointed out that influenza attacked horses in very local epidemics, so that the majority of horses on one side of a yard might be attacked, whilst there was not a single sick horse on the other side. These prevalences and exceptions are altogether unaccountable, but the probability of the disease is in tenfold ratio to the number of horses inhabiting a stable. Two or three shut up in a comparatively close stable would escape, and out of thirty distributed through ten or fifteen little stables, not one would be affected. But in a stable containing ten or twelve horses, although proportionately larger and better ventilated, the disease would assuredly appear, and when it enters one of the largest stables almost every horse is affected. Horsekeepers may also suffer from horsepox or “grease,” a specific eruption transmissible from the horse to man, of which further details are given at page 246.

Much riding early in life may produce a condition of knock-knee or bowed legs quite apart from rickets. Later in life, the tendon of the adductor longus muscle at its point of origin below the spine of the pubes, and more rarely the tendon of the adductor magnus, may become partially calcified, leading to the condition known as “cavalryman’s leg,” whilst the calcified portion is known as “rider’s bone.” A wrench or sprain of the adductors, “rider’s sprain,” is not an uncommon accident in the hunting-field. It leads to a very troublesome form of chronic inflammation, which may quite prevent riding exercise, and has proved the starting-point of a “rider’s bone.” “Rider’s bursæ” are described as occurring in the fold of the groin and on the inner side of the knee. They are probably enlargements of the ilio-psoas bursa or of the bursæ situated between the semi-membranosus and semi-tendinosus tendons, or beneath the inner head of the gastrocnemius muscle, but I have never seen cases of either occurring in riders, though they are common enough in tuberculous patients. Popliteal aneurism is said to be somewhat more common in jockeys and grooms than in other persons, and these occupations lead also to an increased liability to fractures and dislocations.

_Cattle._

(4) _Butchers, Slaughterers, and Tanners._--Butchers and slaughterers suffer from an undue tendency to diseases of the throat and chest, because their occupation, at any rate in London, entails very early rising to attend market, their shops are usually quite open, and they are some of the few tradesmen who still cry their wares. Their wounds are very likely to become poisoned, and as they are often overfed and gross in habit, erysipelas is a common sequel of slight injuries. Many porters from the Metropolitan Meat Market apply annually at St Bartholomew’s Hospital for the relief of hernia and ruptured muscles, which they attribute to the strains produced by carrying heavy carcasses and to slipping on greasy pavements. The hospital practice seems also to contain a considerable proportion of cases of aneurism amongst the same class of men.

It is said that the habit of eating tiny bits of raw meat from the chopping block sometimes causes butchers to become infected with the various parasitic worms, which can be transmitted in this way. Their meat-eating and beer-drinking habits, coupled with a sedentary occupation, must be held accountable for their obesity and for the frequency with which they suffer from gout.

I do not know whether tanners are liable to any special diseases except anthrax, but in the business of leather-dressing which is carried on in connection with tanning, the various eruptions produced by aniline dyes are not uncommon, and there is some danger of arsenical poisoning from the use of orpiment.

(5) _Cowmen and Dairymaids._--Cowmen and dairymaids in those counties where they are brought into direct contact with cows as milkmaids, are liable to several diseases by reason of their occupations. Foremost amongst these, and of the greatest historical interest, is vaccinia or cowpox, though it is quite a rare complaint in English dairy farms.

Vaccinia is a specific disorder occurring in epidemics amongst bovine animals. It is transmissible to the goat, dog, ass, camel, rabbit, guinea-pig, monkey, and with greater difficulty to the sheep. It is characterised in the cow by a local eruption almost exclusively confined to the udder and teats. The eruption passes through the successive stages of papule, vesicle, and pustule, the number of pocks always being few, and there is considerable constitutional disturbance. The lymph from the vesicles of a cow suffering from pox is sometimes inoculated on the hands of the milkers, when inflamed spots appear more particularly about the joints and tips of the fingers. The spots become vesicular, with a swollen, hard, and inflamed base. The axillary glands become inflamed, and the disorder is attended with some constitutional disturbance. An analogous condition in the horse is called “grease” or horsepox, and inoculation of the horse with cowpox will produce “grease.” Cowpox in bovine animals and “grease” in horses can also be produced by inoculation with human smallpox. Both “grease” and cowpox are transmissible to man by inoculation, both diseases render him to a certain extent immune to smallpox, and both render him less liable to a second attack of cowpox or horsepox. It appears therefore that smallpox, cowpox, and horsepox are very closely allied to each other. They may be identical, the features being modified by transmission through different animals, or they may be descended from a common disease which was more akin to cowpox than smallpox.

Tuberculosis is so common a disease in cows that it is no wonder if phthisis in their attendants sometimes derives its origin from a diseased animal. The disease, however, is much more often carried by the milk, and it is therefore a wise precaution to boil every drop of cow’s milk for three minutes before it is given to a child or to one who is predisposed to consumption. I have seen local tuberculosis of the skin in one or two cases contracted by veterinary surgeons in the course of their duties. Free excision of the affected part has always been followed by prompt healing, and I have never known of any generalisation.

Diphtheria is sometimes carried by milk, the infection being derived either by accidental contamination or from the cow itself. The symptoms of diphtheria in the cow are those of “chapped teats,” viz., rise of temperature and an eruption on the udder and teats. The eruption begins as vesicles, which pass rapidly into pustules, scabs, or ulcers. When the disease is transmitted in this manner the cream and skim milk appear to be more dangerous than the new milk, probably because the organisms have a longer time to grow. Pigeons, turkeys, and cats have also been credited with the power of conveying diphtheria, and in the case of cats the accusation is proved.

There is good reason, too, for thinking that cows suffer from scarlet fever, and that the disease is transmitted by their milk, for in no other way is it possible to account for local epidemics of scarlet fever which have been traced to large dairy farms.

Cows certainly suffer from ringworm, and the tinea is transferred to those who lean their heads against them in the act of milking.

Foot and mouth disease is highly contagious amongst ruminants and pigs. It has often been transmitted to man, usually by the milk of cows suffering from the disease, sometimes by the butter, but most often by direct contact with diseased beasts. Milkmaids, cowmen, shepherds, and veterinary surgeons are thus especially liable to infection. The disease, as it occurs in man, is ushered in by rigors, diarrhœa, and some rise of temperature. On the second or third day a vesicular eruption appears on the gums and tongue, and it may also occur on the fingers or other seat of inoculation. Fortunately the disease as it occurs in man is not serious, and recovery usually takes place spontaneously in the course of a fortnight.

Actinomycosis.--This disease is sometimes derived by inoculation from cattle affected with the fungus, but it comes more often from infected grain. The symptoms are those of a chronic abscess affecting the skin, mucous membranes, or viscera, especially the lungs, liver, and ileo-cæcal portion of the intestine, where it is liable to be mistaken for appendicitis. It appears on the skin in the form of numerous globular masses, which are soft and spongy, and have an indurated erythematous base. Pus which contains the yellow granules characteristic of the disease exudes from the ulcerating points. The disease runs a very chronic course, which is shortened, and the patient cured by enormous doses of iodide of potassium. Doses of a drachm may be given three or four times a day, and the patient not only shows no symptoms of iodism, but improves markedly in general health.

(6) _Shepherds_ suffer by reason of their occupation in two ways. They are of necessity closely associated with dogs, and are thus more liable to hydatids and rabies, whilst from the sheep they obtain flukes, and in the process of dipping they may suffer from arsenical poisoning.

A hydatid is the asexual and cystic form of the _Tænia echinococcus_, a small tapeworm consisting of three segments, found in the intestines of dogs and wolves. The fertilised ova are swallowed with impure water or with uncooked vegetables, like lettuce and watercress, fouled by the excreta of infected dogs. The hydatid cyst develops slowly in any part of the human body. It is most common in the liver and intermuscular connective tissues, but it is not unusual to find a hydatid cyst in the lungs, kidneys, pelvis, and brain, and I have seen specimens in which the vertebræ and os innominatum were involved. The symptoms are very obscure, and are usually dependent upon the amount of pressure exercised by the tumour. There is sometimes a characteristic hydatid thrill, but its absence does not invalidate the diagnosis. For practical purposes the cyst is composed of two layers, an external or adventitious covering formed by irritation from the tissues of the host, and the soft and white but tough internal cyst, filled with a limpid fluid, containing the characteristic hooklets. The inner lining of this cyst develops daughter cysts by a process of budding, though it is sometimes sterile.

The treatment is essentially surgical. Whenever it is possible the tumour should be freely exposed, the fibrous cyst opened, the fluid contents removed, and the whole endocyst withdrawn. The edges of the ectocyst may then be sutured, and the external wound closed if union by first intention can be practically guaranteed. But if there is any doubt as to the probability of securing asepsis it is better to free the edges of the outer cyst from its attachment to the surrounding organs, and then suture it to the sides of the external opening without including the skin. The cavity usually has to be plugged after the removal of a hydatid from the liver.

It is not supposed that the liver fluke, or _Distoma hepaticum_, is transmitted from the sheep to man, as is the hydatid from the dog to the man, but it is probable that the shepherd has become the involuntary host of the distoma in the same way as the sheep, by drinking water containing the amphibious snail (_Limnæus trunculatus_), which is the true intermediate host of the liver fluke in the sheep. This trematode worm has been found in subcutaneous abscesses more often than in the human liver. The treatment, when possible, consists in opening the abscess and thoroughly scraping out its contents, for they show a great tendency to refill.

_Pig-keepers._--It does not appear that pig-keepers suffer from any particular diseases by reason of their occupation. It is possible that where only a few animals are kept and are afterwards eaten by the owners there may be some increased liability to trichiniasis, which is an inflammatory state of the voluntary muscles due to the irritation produced by the presence of the nematode worm, _Trichina spiralis_. I recently saw a young lady who was suffering from a chronic trichinosis. She had numerous hard masses beneath the skin of her legs, which were locally irritable when they first appeared, though they soon ceased to give trouble. At first it was thought that the tumours were multiple fibromata, but on cutting one out and submitting it to microscopic examination it was found to contain encapsuled trichinæ.

D’ARCY POWER.