the serum of their blood is said, by Hewson, to be more milky than that of almost any other animal.

If it were necessary, many other arguments might be advanced to shew how improbable it is that chyle should pass through the lungs unaltered, and be distributed by the aorta to every part of the body. How unfit this fluid is for an extensive circulation, must be apparent to every one.

If then it be admitted that the arteries perform the function of secretion, and if it be allowed that a fluid called chyle passes into the pulmonary artery, and issues from it, not in the form of chyle, but in that of blood, it is evident that chyle is converted into blood by an action peculiar to that artery.

Every part of the body, whether solid or fluid, is the product of secretion. Is it probable that so important a fluid as blood should be without an appropriate organ for its secretion ?

The centrical situation of the pulmonary artery; its proximity to the thoracic duct and to the aorta; renders it peculiarly eligible for the purpose of secreting blood. It almost immediately receives its heterogeneous contents, and converts them into a fluid proper for the aorta to distribute to every part of the body.

That the pulmonary artery performs other important functions I am ready to admit. As I before observed, the aorta, with its ramifications, serves many purposes; the pulmonary artery may, and does answer several. Some of its branches decarbonize* the refluent blood; others secrete a fluid upon the surfaces of the bronchiæ, by means of which they are preserved in an open state; a third set terminates at the commencement of the pulmonary veins; a fourth, converts the chyle into blood, and terminates in the same manner.

* Carbon in a palpable form, during profound sleep, is sometimes deposited upon the lining membrane of the bronchiæ, and is coughed up in combination with a very viscid mucus. The mucus is literally rendered by it, “as black as

a crow."

One circumstance remains to which I promised to direct the attention.

To me it seems probable, that the white appearance of the serum depends upon an action of the sanguiferous system, somewhat similar to that by which the buffy coat is produced upon inflamed blood.

It is stated, that this white serum is frequently met with soon after eating; in other words, when the circulation of the blood has been rendered more rapid by the stimulus of food.

We seldom meet with buff except when there is an increase of vascular action. When the buff is perfectly formed, we generally have a very transparent serum. We now and then meet with a little buff upon arterial blood. We sometimes, but more rarely, see the serum of arterial blood a little white. I therefore am inclined to attribute the white appearance of the serum, and the buffy state of the crassamentum to an increase of vascular action; the difference of the appearance depending upon a modification of that action. In other words, if the stimulus of food were sufficient to produce inflammatory action, instead of a white serum, we should have a buffy crassamentum. Whenever, therefore, I observe a white serum, I infer that more or less of increased vascular action exists. Perhaps I shall be better understood if I state, that under a moderate increase of action a turbid serum will be formed; under an excess of that action a buffy crassamentum, with a transparent

serum.

Buff, or coagulable lymph, and the particles which render the serum turbid, are probably formed at the extremest points of the arterial ramifications.

Should these conjectures receive support or confirmation from the experiments, or the observations of others, some important improvements in the practice of medicine may be founded upon them.

SECTION IV.

ON THE DISEASES OF THE STOMACH, &c.

CHAPTER I.

Dyspepsia.

Anorexia, nausea, vomitus, inflatio, ructus, ruminatio, cardialgia, gastrodynia, pauciora saltem vel plura horum simul concurrentia, plerumque cum alvo adstricta, et sine alio vel ventriculi ipsius, vel aliarum partium, morbo.—Cl. ii. O. ii. G. xlv. CULLENI.

SO UNIVERSAL is the sympathy between the stomach and the other parts of the body, that it is almost impossible for disease to exist in any part, without the stomach being more or less affected by it.

Dyspepsia is generally described as a distinct disease, and many symptoms characteristic of it, such as heartburn, flatulent and acid eructations, constipation, &c. are enumerated; these symptoms are however more frequently sympathetically excited by disease in some other organ, and ought rather to be considersd as symptoms of that disease, than regarded as constituting a disease of the stomach itself.

For the removal therefore of what are called symptoms of dyspepsia, instead of wasting our time and disgusting our patients, by the administration of palliative remedies, we must direct our whole attention to their exciting causes.

Dyspeptic symptoms will be found for the most part to arise from a derangement in the structure or functions of the brain, liver, pancreas, uterus, and kidneys; in the uterus and pancreas more particularly.

An enlargement of the duodenal extremity of the pancreas is a very frequent exciting cause.

Unless we can remove these affections, we shall in

vain ransack the materia medica for remedies calculated to give tone to or allay irritation in the stomach.

I have been thus particular in enumerating the sources from whence dyspeptic symptoms arise, because they are so frequently disregarded in practice, and effervescing draughts by the gallon and magnesia by the pound are consumed, not only without benefit, but with evident prejudice.

I do not intend however to deny that dyspeptic symptoms are sometimes excited by a diseased state of the stomach itself. From the admission of improper substances, or from the immoderate use of proper food, its coats become impaired and its functions disordered.

Dyspepsia, depending upon such causes, may be most effectually remedied by a rigid adherence to an abstemious diet; an entire abstinence from every thing which the patient from repeated experience has found to disagree with him, or to be difficult of digestion; occasionally an emetic; from forty drops to a drachm of the volatile spirits of ammonia three times a day in a glass of water, or moderately bitter infusion of gentian; and every alternate evening five grains of the blue mercurial mass. Against a constipated state of the bowels we must likewise carefully guard.

The following most obstinate case of dyspepsia, submitted to the continued use of the mercurial pill after every other remedy which could be devised had been tried in vain.

CASE XXIII.

Thomas Bush, aged twenty-nine years, by trade a painter, was admitted in the month of November, 1810, labouring under all the symptoms of colica pictonum, with paralysis of the muscles of the fore-arms, and an excessive irritability of stomach.

After constipation was removed, his hands were ex

tended upon splints, and opium, rhubarb, ipecacuanha, bitter infusions, magnesia, fixed and volatile alkalies, in large as well as in small doses, were exhibited, but they all appeared to aggravate rather than relieve the cardialgia, nausea, and sickness, with which he was perpetually tormented.

The stomach was incapable of digesting any thing. Whatever was received into it was ejected from it in the course of one or two hours, without having undergone any sensible alteration.

Under these circumstances, five grains of the blue pill, combined with half a grain of opium, were taken every night. Within a week after its exhibition, he retained food upon his stomach without much difficulty; in a fortnight his gums became affected; the dyspeptic symptoms were nearly removed, and the wrists were evidently stronger. At the end of three weeks, the dyspeptic symptoms had entirely subsided; the extensor muscles of the fore-arms became perfectly obedient to the will, but their action was feeble; it was sufficiently powerful however, to enable him to extend the hands and keep them in a straight line with the arms.

He was discharged in a state of convalescence and recommended to use the Bath waters, under an impression that they would confirm a cure so happily brought about by the use of the mercurial mass.

This case not only shews the advantages which may be derived from the exhibition of mercury in some affections of the stomach; but it proves that that metal is eminently powerful in counteracting the baneful influence of lead.

Pyrosis.

Epigastrii dolor urens, cum copia humoris aquei, plerumque insipidi, aliquando acris eructata.-Cl. ii. O. iii. G. lviii.-CULLENI.

PYROSIS will be most effectually relieved by the practice recommended when treating of dyspepsia.