REMARKS ON THE AFFECTIONS OF MUCOUS MEMBRANES.
80. It is not my design to examine the affections of mucous
membranes; I shall notice only some phenomena, which in these
affections I believe deserve a particular attention, and the
explanation of which I propose to physiological physicians.
81. Why do mucous membranes seldom contract adhesions from
inflammation, since that occurs so frequently in serous surfaces
under the same circumstances? Why does not the internal surface
of the inflamed stomach, intestines, or bladder, adhere in its
various portions like the pleura, tunica vaginalis, testis, &c.
82. Why, in inflammations of mucous membranes, is there an abundant
flow of that fluid which habitually moistens them, and which
constitutes the different kinds of catarrhs, whilst the source of
the fluid that exhales from serous membranes is generally dried up
in analogous cases?
83. Why do polypi, a kind of affection peculiar to mucous
membranes, seldom arise but at the origins of these membranes in
the vicinity of the skin, as in the nose, pharynx, vagina, &c., and
not in their more internal portions, as in the stomach, intestines,
&c.? Does this arise from the peculiarity of the texture that I
have shown mucous membranes to have in the vicinity of those places
where they arise from the skin, or must we attribute this fact to
the more numerous causes of irritation which act upon the origins
of these cavities?
84. Are not aphthæ an isolated inflammatory affection of the glands
of the mucous membranes, whilst catarrhs are characterized by a
general inflammation of all the parts of these membranes?
THE END.
CHARLES WOOD, Printer,
Poppin's Court, Fleet Street, London.
FOOTNOTES:
[A] The following questions have been much disputed: Is there a
cystic and an hepatic bile? Is the one of a different nature from
the other? Does their quantity increase or vary? &c. Contrary,
and even opposite, opinions have been supported by numerous
experiments made upon living animals, as Haller as well observed.
These experiments, though at first sight contradictory, in reality
are not so, as I have had the opportunity of convincing myself, by
repeating them in the different stages of digestion, and during
the abstinence of the animal, which previously had never been done
with precision. The following are what I have observed in dogs
that I have used in my experiments. (1) During abstinence, the
stomach and the small intestines being empty, yellowish clear bile
was found in the hepatic duct and ductus communis choledochus; the
surface of the duodenum and jejunum were stained by a bile which
had the same appearance; the gall bladder was very much distended
by a greenish bitter bile, which was deeper in colour and more in
quantity, according to the length of the abstinence. (2) During the
gastric digestion, which may be prolonged for a sufficient length
of time by giving the dog large pieces of meat, which he swallows
without chewing, appearances were similar. (3) At the commencement
of intestinal digestion, the bile in the hepatic duct was always
found yellowish; that of the ductus communis choledochus deeper in
colour; the gall bladder not so full, and its bile becoming already
more clear. (4) Towards the end of digestion, and immediately
after it, the bile of the hepatic duct, of the ductus communis
choledochus, that contained in the gall bladder, and that which was
spread over the duodenum, were exactly of the same colour as the
common hepatic bile, a clear yellow, having but little bitterness.
The gall bladder was but half full; it was not contracted, but
flaccid.
These observations, repeated a great number of times, evidently
prove, that such is the manner in which the bile flows during
abstinence and during digestion. (1) It appears that the liver is
continually separating from itself a sensible quantity of bile,
which increases during digestion. (2) That which is secreted during
abstinence is divided between the intestine, which is always found
coloured with it, and the gall bladder, which retains it without
transmitting any portion of it through the cystic duct, and where,
thus retained, it acquires a deeper colour and a character of
acrimony, necessary, without doubt, to the digestion which is soon
to follow. (3) When the food, having been digested by the stomach,
passes into the duodenum, then all the hepatic bile, which was
before divided, flows into the intestine, and even in greater
abundance; the gall bladder also pours that which it contains
upon the alimentary pulp, and with which it is then found quite
incorporated. (4) After the intestinal digestion the hepatic bile
diminishes, and begins to flow, part into the duodenum and part
into the gall bladder, where, being then examined, it is clear and
in small quantity, because it has not yet had time either to become
coloured, or to collect.
There is, therefore, this difference between the two kinds of bile,
that the hepatic flows in a continual manner into the intestine,
and the cystic, during the absence of digestion, flows back into
the gall bladder; and whilst that function is going on it passes
towards the duodenum; or rather it is always the same fluid, of
which one part preserves the character it has when it leaves the
liver, and the other part undergoes a change in the gall bladder.
The difference of colour in the cystic bile, according to the time
that it has remained in the gall bladder, is analogous to the
colour of the urine, which becomes deeper as it is retained longer
in its receptacle.
[B] The bile in the gall bladder, the urine in the bladder, and
the semen in the vesicula seminales, are certainly absorbed; but
it is not the fluid itself that re-enters the circulation, but
only its finest parts, some of its principles that we are not well
acquainted with, probably its aqueous or lymphatic portion. This
does not resemble the absorption in the pleura and other analogous
membranes, in which the fluid rejoins the blood in the same state
as it left it.
[C] This is a necessary consequence of the disposition of the
vascular system of the stomach. The arteria coronaria ventriculi
superior being situated transversely between the stomach and the
omentum, and furnishing branches to both, it is evident, that when
the stomach, by separating the duplicatures of the omentum, lodges
itself between them, and this in applying itself over the stomach
becomes shortened, the branches that it receives from that artery
cannot in the same manner apply themselves to it. To effect this
it would be necessary, that they should proceed from the one to
the other without the intermediate trunk that cuts them at right
angles; then the stomach, by distending itself, would separate them
in the same way that it does the omentum, and would lodge between
them, instead of pushing them before it with their common trunk,
and folding them upon themselves.
TRANSCRIBER'S NOTE
Italic text is denoted by _underscores_.
Obvious typographical errors and punctuation errors have been
corrected after careful comparison with other occurrences within
the text and consultation of external sources.
Except for those changes noted below, all misspellings in the text,
and inconsistent or archaic usage, have been retained. For example,
newly-born, newly born; circumvolutions; atmospherical.
Pg v (TOC), page '101' replaced by '98'.
Pg 54, 'the mach, small' replaced by 'the stomach, small'.
Pg 57, 'membranes is spread' replaced by 'membrane is spread'.
Pg 81, 'OF THE SYMPATHY' replaced by 'OF THE SYMPATHIES'.
Pg 86, 'fine pelicle' replaced by 'fine pellicle'.
Pg 90, 'those asphyxies' replaced by 'those asphyxias'.