I doubt if it is adequately realised what a large amount of alkaline saliva passes into the stomach as the result of prolonged mastication. Its presence there serves the useful purpose of prolonging the period of starch digestion within the stomach, while it further aids gastric digestion not only by exciting the secretion of gastric juice, but also by its influence on the reaction of the gastric contents; it can scarcely be doubted that the effect is on the whole one favourable to digestion in general. We have just seen that defective mastication may predispose to hyperchlorhydria by allowing an excess of pure starch to pass into the stomach, and I suggest that it may further operate in the same direction by cheating the stomach of its due supply of alkaline saliva. Now the saliva in this affection is apt, as was pointed out by Sir William Roberts, to be superalkaline, and for this reason he recommended his acid-dyspeptics to excite the flow of it by chewing gum-mastic with the object of neutralising the gastric hyperacidity.

That relief can thus be obtained there can be no doubt; but it is surely more rational to get the patient to stimulate his salivary glands by masticating actual food, by which we secure the additional advantages accruing from its complete insalivation and comminution as well as from the reflex gastric effects. Actuated by these considerations, I have long been in the habit of recommending hyperchlorhydriacs to subject their food to prolonged mastication, this being, in my belief, the most rational and effective way of breaking the stomach of its vicious habit. In extreme cases we must insist that each morsel of food should be chewed at least one hundred times and not permit any relaxation of this severe discipline, until the stomach has been schooled into healthier ways.

1 Brit. Med. Jour., Epitome, vol. i., 1903, p. 45.

Evils in connection with the jaws and their appendages and the adjacent structures: the nasal passages, naso-pharynx; and faucial tonsils. - In those who do not masticate properly in early life these parts fail to develop as they should, and they are on this account alone predisposed to disease; their resistance to disease is still further lowered by the fact of their blood and lymph flow not being adequately stimulated by the vigorous exercise of the masticatory muscles. Now we have seen that the great cause of defective mastication in children is the softness of the food given them and that the feeding of them upon an excess of soft food, especially the starchy kind, disturbs digestion, induces toxaemia, and in this way evokes a catarrhal tendency. In children thus fed we have therefore several conditions which make for disease in the parts under consideration - defective development, sluggish circulation, and toxic saturation. Is it any wonder that the modern child should be liable to disease in these regions, that he should so frequently suffer from rhinitis, naso-pharyngitis, tonsillitis, and from hypertrophy of the pharyngeal tonsil ("adenoids") and of the faucial tonsils?

It is in this way that I would explain the frequency of adenoids among the children of civilised communities. I claim, in fact, that this disease is largely dietetic in origin. I submit that a child whose nasal apparatus and nasopharynx are well-grown and habitually bathed by a stream of pure blood and lymph, periodically accelerated by an ample and vigorous use of the masticatory muscles, is unlikely to contract adenoids. On the other hand, I contend that a child in whom these parts are ill-developed and bathed by an habitually sluggish stream of tainted blood and lymph - one, ie., that is not only poisoned, but rarely, if ever, hurried along its lazy course by due exercise of the muscles of mastication - I submit that such a child runs great risk of contracting the disease. The influence in setting up adenoids of toxic saturation with its resulting catarrhal tendency is shown by the frequency with which this affection follows upon the rhinitis and naso-pharyngitis of measles and diphtheria, and in order to realise how greatly the circulation of blood and lymph in the walls of the naso-pharynx must be influenced by mastication, one has but to remember how very closely the pterygoids are related to this region; in exploring it for adenoids they can, indeed, often be felt to stand out prominently.1

1A further aid to the circulation in the naso-pharynx is afforded by the lusty use of the voice. It is natural for the young human to cry and to shout, and unless this instinct is allowed full play the child is apt to suffer in health. I cannot but think that the modern child is too much repressed in this respect, and that he is not afforded, especially in towns, proper.

This, then, is my explanation of the truly fearful prevalence of adenoids among the moderns. It is essentially a disease of pap-fed peoples. A child may, with the one exception that he is fed on a pappy, super-saccharide diet, be brought up under ideal health conditions. He may live in the heart of a dry, open country, far from the darkness, dust, and tainted atmosphere of the town, sleep with the windows open all night, live out of doors all day, be fed on the most nourishing (too nourishing, it may be) food, be clothed after the most approved methods, and yet, in spite of all this, we may find his naso-pharynx packed with adenoids. This disease is, in fact, scarcely less prevalent in the country than in the towns, scarcely less common among the rich than among the poor. Yet in primitive communities it is practically unknown. And what, I would ask, is the one condition in the material environment of my supposititious child differing from that of the primitive child? What but the factor of diet? Therefore, I say, the prevalence of adenoids among moderns must be the result of the modern system of feeding children, and the defective mastication which goes along with it.

That the foregoing is a grave indictment opportunity of venting his vocal energy in out-door play. May we not have here a contributory factor in the causation of adenoids? against that system, it need scarcely be said. For adenoid disease is fraught with many evils, among them mental hebetude, blocking of the Eustachian tubes, and manifold other auditory troubles, gastro-intestinal disturbances from the passage into the stomach of unhealthy discharges, and, most serious of all, nasal obstruction and consequent mouth-breathing. So serious are the evils connected with this latter habit that they demand more than a passing reference. Pronounced adenoid disease is always associated with mouth-breathing, and there can be no doubt that in the majority of these cases, the nasal obstruction is not in the nasal passages primarily, but is due to a blockage of the posterior nares by the adenoid growths, for it generally happens that nasal breathing is rapidly re-established after their removal, though in a certain proportion of cases the obstruction still persists, and has to be dealt with by treatment directed to the nasal passages themselves.

Some have, indeed, contended that a primary nasal obstruction is one important factor in the induction of adenoids, leading as it does to a dry-cupping of the nasopharynx during inspiration and to a consequent congestion of its lining membrane. I am quite ready to allow that this mechanism may play some part in causation, and such an assumption is in entire harmony with my main content tion that adenoid disease is of dietetic origin, for nasal obstruction in children, other than that caused by adenoids, is mainly due to defective development of the nasal passages coupled with inflammation of their lining membrane, both of which conditions may, as we have seen, be essentially the outcome of defective diet.

Coming now to the evils resulting from mouth-breathing, we have first to remember that normally the air is inhaled through the nose, and is thus warmed, moistened, and filtered before being allowed to pass into the lungs; but in the mouth-breather the air, which may be dry, cold, and dust-laden, passes at once unprepared through the mouth into the lungs, impinging in its passage against the pharynx, thus drying and mechanically irritating the mouth, pharynx, larynx, and bronchial tubes, all of which are thereby predisposed to disease. In this way laryngitis and bronchitis, nay, even phthisis, may be induced. Dental caries is also predisposed to by the habit of breathing through the mouth. Mouth-breathing further interferes with the proper development of the cranial bones, but especially of the maxilla, giving rise to what may be termed the "mouth-breather's jaw," so characteristic is it. I do not propose to discuss here the mechanism by which this deformity is produced, interesting though the question is; suffice it to say that nasal breathing is essential to the normal development of the jaws.

The deformity in question, though it involves the maxilla chiefly, affects also the mandible from the fact of its being, to a large extent, moulded on the maxilla; in typical cases the maxilla is small and its alveolar ridge does not attain its normal length, but is compressed laterally towards the sagittal plane, giving rise to the false appearance of a "high arch" and often thrusting the anterior portion of the ridge forwards; the teeth, the growth of which is not so much interfered with as that of the imbedding bone, are thus prevented from taking up their proper positions and show irregularity, sometimes extreme. Dental irregularity may also, as we shall see, result from inadequate use of the jaws in mastication, but not to the extent which is frequently observed in the mouth-breather's jaws, and therefore pronounced dental irregularity always shows that there has been protracted nasal obstruction, and this in the vast majority of cases implies the existence of adenoids, past or present; I say in the "vast majority," for in a few rare cases long-continued nasal obstruction in children originates primarily in the nose and may lead to the typical mouth-breather's jaw, with the resulting dental irregularity.