the blood, and is separated in all the excretions and secretions; and in the stomach this abnormal excrementitious substance appears to act as a direct irritant.

XVI. Both functional and organic diseases of the uterus are causes of vomiting. In dysmenorrhoea most distressing irritability is occasionally set up; and in pregnancy, vomiting may be so severe as to exhaust and completely to prostrate the patient.

XVII. The remaining causes of vomiting arise from the condition of the nervous system, and are most interesting and important in the correct diagnosis of disease; the first of these is a diseased condition of the spine. The splanchnic nerves pass from the spinal cord to the large sympathetic ganglion of the abdomen, and constitute an intimate connection between these centres of nerve force; in those diseases, however, of the spine in which we have observed irritability of the stomach other sources of disturbance have been present.

XVIII. At the onset of acute diseases, especially the exanthems, fevers, pyæmia, erysipelas, &c., vomiting is often present. It is not known how this is produced, whether directly by the altered condition of the nervous system, or secondarily from the state of the blood. Sudden nervous shock, fright, &c., will produce vomiting; and in some more chronic diseases, when the blood is altered in character, as in renal disease and even gout, the same symptom is occasionally very intractable, as previously mentioned.

Dr. Graves, in his Clinical Medicine,' makes the following valuable remarks in reference to this subject:"Every fever which commences with vomiting and diarrhoea, whether it be scarlatina, or measles, or typhus, is a fever of a threatening aspect; and in all such fevers the practitioner should be constantly on the watch, and pay the most unremitting attention to the state of the brain. There is much difference between the vomiting and diarrhoea of gastro-enteritis and this cerebral diarrhoea and vomiting. The latter sets in generally at a very early period of the disease, perhaps on the first or second day, and is seldom accompanied by the red and furred tongue, the bitter taste of the mouth, the burning thirst, and the epigastric tenderness which belong to gastro-enteric inflammation." He also states very truly, that in cerebral disease there is often a large quantity of bile rejected by vomiting, and passed also by stool; and that leeching the abdomen is less efficacious in cerebral inflammation than in gastro-enteritis.

Very little is known as to the proximate cause of vomiting in cholera and in yellow fever, but we sometimes find in the intermittents of our own country that it is a prominent symptom; and we have several times witnessed instances in which vomiting, excited possibly by uterine or hepatic mischief, assumed regular periodicity in those who had been exposed to miasmatic poison.

XIX. Irritation of the peripheral branches of the

pneumo-gastric nerve in the abdomen has already been referred to as one cause of vomiting in disease affecting the organs to which they are supplied; but the same nerve may be irritated at its peripheral branches in the chest, and at its origin in the brain. Disease of the brain, then, is another cause of vomiting, and one which it is important to bear in mind in the diagnosis of disease; too often the so-called bilious attacks of children are the first indications of acute hydrocephalus. The irritability of the stomach is sometimes so great that vomiting is at once produced when the patient is raised from the recumbent position. The diagnosis of these cases is sometimes exceedingly difficult when commencing with symptoms of true gastro-enteric disease; but it would be well if the remark of the great authority in clinical medicine just quoted were borne in mind, that "in all feverish complaints where during the course of the disease the stomach becomes irritable without any obvious cause, and where vomiting occurs without any epigastric tenderness, you may expect congestion or incipient inflammation of the brain or its membranes."

In simple cerebral disease the abdomen is generally collapsed; in primary abdominal disease there is, on the contrary, distension. This difficulty in diagnosis is not, however, limited to very young subjects. In strumous disease of the brain, the vomiting is sometimes excessive; so also in disease of the ear extending to the membranes of the brain.

After concussion, vomiting comes on, and in some cases, when inflammatory disease has followed, and suppuration has taken place, this symptom is excessive. One of the most severe cases of secondary vomiting which I ever witnessed was of this kind. A man in middle life had received a blow at the back of the head; cerebral symptoms came on, and suppuration took place at the origin of the pneumogastric nerve; the membranes were adherent at that part for the space of half an inch, and about a drachm of pus was effused. The vomiting had been excessive, and anything swallowed was rejected with violence beyond the extremity of the bed.

XX, Disease of the lungs, or irritation of the pulmonary branches of the pneumogastric nerve, is the last cause of vomiting to which we refer. The vomiting in whooping-cough appears to be of this kind, and equally so that which is often present at the early stage of phthisis; the same symptom may occur in acute as well as in chronic disease of the lung. Sir Henry Marsh has mentioned early phthisis as one of the causes of the irritability of stomach, to which he has given the name of regurgitative disease; and too frequently this irritation leads to the unfortunate expression, that the symptoms of early tubercular disease of the lung are "all stomach." There may be no physical signs produced by scattered tubercles studded throughout the lung tissue, and by overlooking the true character of the

disease, the period of effective treatment, by change of climate and other means, may quickly pass by. It seems, that as the pulmonary disease advances and disorganisation takes place, this condition of irritability is lessened, although we too often find that the paroxysms of cough are productive of violent vomiting.

At the onset of acute disease, both of the pleura and of the lung, it is very frequent to find irritability of the stomach induced, with loss of appetite and furred tongue; and we have many times seen the true character of the disease entirely overlooked from the neglect of proper examination of the chest. If acute pleurisy take place on the right side, the severe pain with vomiting is at once attributed to disease of the liver; and if on the left side, especially when effusion has taken place, and when the heart is pushed over to the median line, pain and tenderness at the scrobiculus cordis is regarded as an indication of gastric complication. Proper examination will prevent these mistakes; but if the acute inflammatory disease be confined to the diaphragmatic surface, the stethoscopic signs are for a short time obscured, until the costal pleura becomes involved. In a patient lately under my care, the malady had been regarded as acute hepatitis, from the circumstance above mentioned; and in another, the complaint was said to be wholly gastric, although the left pleura was full of fluid.

Pyrosis or Water Brash is a symptom to which espe