may safely diagnose tuberculosis.* Unless, then, we can obtain some positive evidence, such as that afforded by the thermometer, it is better in the case of an infant to reserve a decision, until some more decided symptoms are manifested; and these are seldom long postponed. Localisation of the disease soon draws attention to some especial organ, usually the lungs or the bronchial glands.

In the case of older children the diagnosis rests upon steady emaciation, accompanied by more or less irregular febrile disturbance, without any serious local lesion to account for the symptoms. Under such circumstances worms are often suspected, and purgative after purgative is given to clear out the supposed parasites from the bowels. As has been already stated, however, all the symptoms usually attributed to worms may be present, although repeated aperients fail to produce any evidence of their existence. A condition of the alimentary canal is frequently noticed in children which consists in abundant secretion of intestinal mucus, causing fermentation of food, and great impediment to digestion and assimilation. This does not necessarily lead to the formation of tubercle, although it is sometimes followed by ill-defined spots of dulness about the lungs, and by glandular enlargements. These phenomena would perhaps be more correctly ascribed to scrofulous changes than to true tubercle, and they are besides by no means a necessary result of the derangement. One essential difference between this disease and tuberculosis is seen in the fact, that by proper measures the former can be readily cured, and the result of treatment becomes, therefore, a test of the nature of the disorder.†

In the diagnosis of tuberculosis it is important not to be misled by the condition of the stomach and bowels. It

* On the Temperature of the Body as a Means of Diagnosis in Phthisis and Tuberculosis, by Sydney Ringer, M.D. London, 1865.

For a fuller description of this exceedingly common derangement, see the Chapter on Worms.

often happens that there is, in addition to slight febrile disturbance, a little diarrhoea, with unhealthy-looking offensive motions, and loss of appetite. The attention is apt, therefore, to be directed entirely to these obvious points to the exclusion of the more serious affection of which they are merely accompaniments. In such cases a diagnosis can usually be made by inquiring whether the general symptoms preceded or followed the intestinal derangement. The influence of remedies is also an important guide. In the case of tuberculosis, the general symptoms continue after the condition of the bowels has become improved.

Causes.-Tuberculosis is a diathetic disease; in other words, it is the result of a constitutional tendency, more or less pronounced, to this particular form of pathological lesion. Of the children who are born with this constitutional predisposition a large number come of tubercular parents, or of families in which some members suffer, or have suffered, from the disease. It does not, however, follow that tubercular parents must necessarily have tubercular children. Such children may grow up without evincing any tendency to the disease, the predisposition either not having been manifested in them, or if present, having been effaced by the care and attention to hygienic rules with which the children have been reared. The tendency, whether hereditary or not, may be of itself sufficiently potent to give rise to the disease without the influence of any external causes to which such development can be attributed or it may remain latent until roused by circumstances to assert itself, and to produce its natural consequences. Of the children who become the subjects of this disease a certain proportion are descended from parents in whom no similar tendency is manifested, in families altogether free from the tuberculous taint. It seems probable, therefore, that the tuberculous diathesis can be acquired by children whose constitution is at birth entirely free from any such predisposition.

The exciting causes which may determine the development of this diathetic state consist of anything which interferes with the nutrition of the body, whether by preventing the introduction of nutriment into the system, or by obstructing the escape of waste matter whose removal is indispensable to the proper working of the different functions. In this respect it resembles syphilis and scrofulosis, the two other diathetic diseases of children. In them, too, the constitutional tendency, as yet latent, may be awakened by any cause which interferes temporarily with nutrition, and therefore lowers for a time the natural resisting power of the system against disease. Such causes are impure air, insufficient or improper food, cold and damp, want of sunlight and of exercise; a combination of these will in any case awaken the dormant tendency and excite its manifestations.

Certain diseases may also be the starting-point for the development of tubercle in subjects predisposed to the disease. Of these pneumonia may excite the formation of tubercle in the lung. No doubt many of the cases described as tubercle occurring as a result of pulmonary inflammation have been merely cases of scrofulous pneumonia, the socalled tubercle being the yellow infiltrated deposit which is the result of that special form of the disease; but this pneumonic consolidation may itself be the exciting cause of the formation of true grey tubercle in the tissue around it (see Pulmonary Phthisis).

Measles and whooping-cough are also often the cause of the tubercular manifestation, but seldom, according to MM. Rilliet and Barthez, except in conjunction with the other exciting causes which have been mentioned. In these cases it is especially the lungs and the bronchial glands which suffer from the presence of tubercle.*

*The question of the inoculability of tubercle has lately been the subject of investigation. The first experiments were made by M. Villemin, who laid the results of his inquiries before the French Academy in 1865. The

Prevention. If the mother is consumptive, she should on no account be allowed to suckle her child longer than the end of the first month; a healthy wet-nurse should then be provided to take her place. So much has been said in the present volume as to the feeding and general management of young children, that it will not be necessary to repeat in this place the different rules for the diet, clothing, etc., of infants, which have been already laid down. The reader is referred to the section containing the treatment of simple

investigations have been continued in England by Drs. Andrew Clark, Wilson Fox, Sanderson, and by Mr. Simon. From their experiments it appears that in the guinea-pig, or rabbit, the careful introduction of tuberculous matter under the skin is followed by the formation of a pathological product, which differs in no appreciable respect, according to Dr. Fox,* from ordinary grey tubercle, as that occurs in the human subject, either by its naked eye or microscopic characters, by its mode of distribution, the organs affected, or even the parts of the organs affected. Dr. Andrew Clark pointed out that, not only tubercle, but other matters non-tubercular would produce the same result; and Dr. Sanderson showed that even the local irritation excited by the introduction of a seton was as capable, under certain circumstances, of producing tubercle as any of the animal substances which had previously been experimented with.

With respect to the identity or non-identity with true grey granulations of the pathological appearances produced by inoculation, the experimenters differ. Dr. Wilson Fox advocates the view of the true, tuberculous nature of these formations, grounding his opinion upon the fact that in the lung the point of departure is in no respect from the vascular apparatus, the new structure not being an infiltration of the alveoli, but a thickening of the wall of the air-cell which finally closes the vesicle. The air-cell, he states, is the last thing to be occluded, and, even in the densest masses, examined with a binocular, a certain transparency can still be seen, distinctly in some places, showing that central portions of the alveoli are still hollow." Dr. Clark, however, maintains that these products, whatever they may really be, are at any rate not tubercular; for although anatomically they may resemble tubercles, clinically they differ from them in almost every particular. He believes that in determining the nature of a pathological product its clinical history is of infinitely greater value than its anatomical condition.

* See Lecture by Dr. Wilson Fox on the Artificial Production of Tubercle in the Lower Animals, delivered at the Royal College of Physicians, May 15th, 1868. Published in the Lancet for May 23-30, 1868.

atrophy, and that on the prevention of diarrhoea, for full information upon these points.

The diet of an older child should also be so arranged that he may take as much as he can readily digest, but no more. Animal food should be given to him only once in the day, and should be either roasted or boiled: meat cooked a second time, as hashes, or stews, or meat fried in grease, are less digestible, and should not be allowed. After the age of two years a child should take four meals a-day: of these two should consist of bread and milk; a third of meat, finely minced at the first, afterwards cut into small pieces, with a little potatoe carefully mashed, and gravy; a fourth of farinaceous pudding, or an egg lightly boiled. The milk should, if possible, be fresh from the cow; if not, a tablespoonful of cream should be added. It is important to accustom the child early to masticate his food thoroughly: this point should be always attended to. Children often wake hungry in the early morning: it is well in such cases to place, overnight, a piece of dry stale bread, or a plain biscuit, by the side of their bed, so that they may not be forced to wait without food until their breakfast is prepared.

Well ventilated rooms, fresh air, and plenty of exercise have already been insisted upon. The skin should be kept perfectly clean by cold or tepid sponging over the whole

body, in a bath, twice a day, and should be afterwards excited gently to act by friction with the hand, as has been previously recommended.

The dress should be warm, but loose: tight waist-bands, and, in girls, stays, are exceedingly injurious. Nothing should be allowed to interfere with the free play of the chest. Pressure upon the ribs not only prevents a proper expansion of the lungs, but also is apt to cause displacement of the liver and stomach, and much derangement of the functions of digestion and respiration may be the consequence. "The only way," says Dr. Underwood,* "in which

* Diseases of Children, edited by Henry Davies, M.D. London, 1846.