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to say in his paper on this subject,“ there are few dead into chyle, the food is first intimately mixed with the Digestion. bodies in which the stomach at its great end is not in general secretions of the stomach, and after it has been Digestian some degree digested."

acted on by them, the solvent liquor is poured upon it, 165 but the

That the chyle is not formed there, and that it is by which the nutritious part is dissolved. This solution chvle form- commonly formed before the food passes through the py- is afterwards conveyed into the pyloric portion, where ed in the lorus, is proved by the result of soine experiments made it is mixed with the secretions peculiar to that cavity, pyloric por. by Mr Hunter upon dogs, in the year 1760. The dogs and converted into chyle.

were killed while digestion was going on; and in all, “ The great strength of the muscles of the pyloric
the food was least dissolved, or even mixed, towards the portion of some stomachs will, by their action, com-
great end of the stomach, but became more and more press the contents, and separate the chyle from the in-
so towards the pylorus, just within which it was mixed digestible part of the food.
with a whitish fluid like cream,

“ In animals whose food is easy of digestion, the sto. Solvent li. From the result of these experiments, as well as from mach consists of a cardiac and pyloric portion only; but quor se.

the analogy of other animals, it is reasonable to believe, in those whose food is difficult ef digestion, other parts creted by that the glands situated at the termination of the cuticu are superadded, in which it undergoes a preparation beglands near

lar lining of the æsophagus, which are described by Mr fore it is submitted to that process.” the gullet.

Home, secrete the solvent liquor, which is occasionally The action of the juices of the stomach, or of what Action a poured on the food, so as to be intimately mixed with it we call the gastric juice, appears to have much more ef- the gastrie before it is removed from the cardiac portion ; and the fect in the process of chymification, than the muscular

juice. 167 muscular contraction retains it there, till this takes place. action of the stomach, though the dissolving power of Curvature Such contraction being occasionally required in the this fluid seems to be proportionally less in those aniof the sto- stomach, accounts for its being more or less bent upon mals that have the most muscular stomachs. The gacounted for itself, as by this structure it is more readily divided into stric juice of granivorous birds is capable of dissolving

two portions, by the action of the muscular fibres at that "flesh; but when this is entire, it requires four or fire part where the angle is formed.

days for solution ; whereas when bruised, half that time This contraction also explains why the contents of is sufficient. Even grain is not dissolved in it except the stomach are not completely discharged from the first when bruised. The gastric juice of animals with intereffect of an emetic; and by it Mr Home thinks we may niediate stomachs dissolves flesh and cartilage, but not

explain the cramp of the stomach, and some kinds of in bone. It is incapable of dissolving entire seeds. In 168 digestion.

animals with membranous stomachs, the gastric juice is Ornitho After comparing the stomachs of several carnivorous extremely active, and seems to be almost the only agent *- rinchus the animals with that of man; in tracing the gradation from : in the digestive process. In some of these animals

, real link

carnivorous beasts through the bat tribe to birds of prey, however, as the ruminating tribes, this fluid has no efbetween quadrupeds

Mr Home remarks, that “the only real link between fect on the food, unless it be bruised, or thoroughly and birds. the stomachs of quadrupeds and birds is that of the or- masticated. Spallanzani found, that owls digest Hesh

nithorinchus (or platypus), which, lowever, is more an and bones, but not grain ;--that the gastric juice of the approach to the gizzard, heing lined with a cuticle con eagle dissolves bread and bone, and even animal and taining sand, and baving the same relative situation to vegetable matters, when it is taken out of the body;the æsophagus and duodenum. The food of this animal "that a wood pigeon may be gradually brought to live is not known; it is probably of both kinds; the papillæ on flesh ;-that the owl and falcon do not digest bread;

at the pylorus; which appear to be the secretory ducts-that the gastric juice of the dog dissolves even the 169 of glands, are peculiar to it.

enamel of the teeth. General From the facts and observations brought forward in Hence, in every order of animals, the gastric juice is conclusions, this valuable paper, Mr Home deduces the following the principal cause of digestion, and it agrees in all in

general conclusions. * “ That the solvent liquor is se- many properties, and differs in others. In the frog, the i creted from glands of a somewhat similar structure in newt, scaly fishes, and other cold-blooded animals, it pro

all animals, but much larger and more conspicuous in duces digestion in a temperature nearly equal to that of some than in others.

the atmosphere. In warm-blooded animals it is capable “ That these glands are always situated near the ori- of dissolving the aliment in a degree of heat lower than fice of the cavity, the contents of which are exposed to that of these animals. In them too the food is digested their secretion.

in a few hours, whereas in the opposite kind it requires “That the viscid substance found on the internal several days, and even weeks, particularly in serpents ; membrane of all the stomacbs that were examined re likewise, the gastric juice of the gallinaceous class can cently after death, is reduced to this state by a secre dissolve only bodies of a soft and yielding texture, and tion from the whole surface of the stomach, which coa previously triturated: whilst in others, as serpents, the gulates albumen. This appears to be proved, by every heron, birds of prev, and the dog, it decomposes subpart of the fourth cavity of tbe calf's stomach having stances of great tenacity, as ligaments and tendons ; the property of coagulating milk.

and even of considerable hardness, as the most compact “ This property in the general secretion of the sto bone. Man belongs to this class, but his gastric juice mach leads to an opinion, that the coagulation of fluid seems to have no action on the hardest kinds of bones. substances is necessary for their being acted on by the Some species, likewise, are incapable of digesting vegesolvent liquor; and a practical observation of the late tables, as birds of prey; but man, the dog, cat, crows, Mr Hunter, that weak stomachs can digest only solid &c. dissolve the individuals of both kingdoms alike, and food, is in confirmation of it.

are omnivorous, and in general their gastric juices pro" That in converting animal and vegetable substances duce these effects out of the body.

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For an account of the chemical nature and properties nous and spirituous liquors and old cheese in small quanDigestion. of the gastric juice, see CHEMISTRY, No 2551. tities, and by various bitters. It is retarded by large Digestion.

The process of chymification depends also, in a great quantities of diluting liquors, especially when taken

measure, on the nature of the substances employed as hot; by acids and astringents taken a short time after Solubility

food, as some of these are much more soluble than eatings by unctuous substances; by mental employ

others. On this subject much information may be de- ment, or severe bodily exercise, too soon after a meal; * Stark's rived by consulting the experiments of Dr Stark *, and and by leaning with the breast against a table.

172 Works, those of M. Gosse of Geneva, an abstract of which is It may be proper here to notice the various opinions Various

theories of given in Johnson's Animal Chemistry, vol. i. p. 207. that have been entertained respecting the immediate

digestion. From the latter experiments it appears, Ist, That the fol cause of digestion. The principal of these opinions are, lowing substances are either insoluble, or are not digest that it is produced by coction or beat; by trituration ed in the usual time in the stomach. in the stomach; by fermentation, or by putrefaction.

173 Animal substances. 1. Tendinous parts. 2. Bones. That it is not brought about by heat alone, will ap- Heat. 3. Oily or fatty parts. 4. Indurated white of egg. pear from the circumstance, that many cold blooded

Vegetable substances. 1. Oily or emulsive seeds. animals digest their food as completely, though not so Expressed oils of different nuts and kernels. 3. Dried expeditiously, as warm-blooded animals. grapes. 4. Rind of farinaceous substances. 5. Pods of That it is not effected by trituration in the stomach Trituration. beans and pease. 6. Skins of stone fruits. 7. Husks of alone, is evident from the experiments that have been fruit, with grains or seeds. 8. Capsules of fruit, with made by Spallanzani, Stevens, and others, of giving to grains. 9. Ligneous stones of fruits. 10. The gastric animals food enclosed in hollow perforated balls, sutfjuice does not destroy the life of some seeds; hence bit- ciently strong to resist the muscular power of the stoter-sweet, hemp, misletoe, and other plants which some mach; us the balls have been found empty, and not times grow upon trees, are produced by the means of compressed. the excrements of birds, the kernels of seeds being de That it is not owing to fermentation is proved by the Fermentafended from the menstruam by their exterior covering. circumstance, that the more perfectly digestion proceeds,

2d, That the following are partly soluble, viz. the less is the evolution of gases in the stomach; the

Animal substances. 1. Pork dressed various ways. 2. contrary of which would be the case, if digestion con-
Black puddings. 3. Fritters of eggs, fried eggs and sisted in a fermentation of the aliment.

176 bacon.

That it does not depend on putridity, is evidenced by Putridity. Vegetable Substances.--1. Salads of different kinds, the observations that have been made on putrid food rendered more so when dressed. 2. White of cabbage given to dogs, and examined some time alter, when it less soluble than red. 3. Beet, cardoons, onions, and was found perfectly sweet. leeks. 4. Root of scurvy-grass, red and yellow carrots, On the whole it appears, that in most animals the disuccory, are more insoluble in the form of salad than gestion of food in the stomach depends partly on a due any other way. 5. Pulp of fruit with acids, when not degree of heat, partly on the vital action of the stomach, fluid. 6. Warm bread and sweet pastry, from their pro but chiefly on the action of the gastric juice. ducing acidity. 7. Fresh and dry figs. By frying all When the aliments have been converted in the sto- Chylifica.

tion. these substances in butter or oil they become still less mach to the crude pulp called chyme, they are gradually soluble. If they are not dissolved in the stomach, they propelled through the pylorus into the duodenum, where are, however, in the course of their passage through the they are mixed with the bile, the pancreatic juice, and intestines.

the fluids that are separated by the mucous coat of that 3d, That the following are soluble, or easy of dige- intestine, and are thus reduced to a still finer pulp, constion, being generally reduced to chyme in an hour, or taining, as one of its principal ingredients, the nutritious an hour and a half.

flaid called chyle, the nature and properties of wbich, Animal Substances.-1. Veal, lamb, and in general as they have been but slightly mentioned in the former the flesh of young animals, are sooner dissolved than that parts of this work, fall to be noticed bere.

178

Properties of old. 3. Cows milk. 4. Perch boil. The properties of chyle bave not been minutely in

of chyle. ed with a little salt and parsley. . When fried or sea vestigated; but according to Fordyce, as far as experisoned with oil, wine, and white sauce, it is not so ment has been carried, the chyle of quadrupeds is so soluble.

similar to that of man, and of each other, as hardly to
Vegetable Substances. 1. Herbs, as spinach, niixed be distinguished, even in tribes the most opposite to each
with sorrel, are less soluble. Celery, Tops of aspara other in their structure, food, and habits of life. As far
gus, hops, and the ornithogalus of the Pyrenees. 2. Bot as we can perceive, the chyle of a dog or a wolf differs
tom of artichokes. 3. Boiled pulp of fruits, seasoned in nothing from that of a sheep or an ox.

4. Pulp or meal of farinaceous seeds. The chyle consists of three parts; one part which is
5. Different sorts of wheaten bread, without butter, the fluid, and contained in the lacteals, but coagulates on
second day after baking; the crust more so than the extravasation.
crumb. Salted bread of Geneva more so than that of The second part consists of a fluid, which is coagu-
Paris without salt; brown bread in proportion as it lable by heat, and in all its properties hitherto observed,
contains more bran is less soluble. 6. Rapes, turnips, it is similar to the serum of the blood.
potatoes, parsnips, not too old. 7. Gum arabic, but its The third part consists of globules, which render the
acid is soon felt. The Arabians use it as food.

whole white and opake. These globules have been sup-
The solvent power of the gastric juice is increased by posed by many to be an expressed oil; but this has not
various stimulants, especially by those called condiments, been proved. Neither has it been perfectly densonstrated
as sea salt, spices, mustard, vinegar, as well as by vi- that sugar is contained in the chyle, although it has
Vol. XVI, Part II.

+

been

177

2. Fresh eggs.

with sugar.

3 Q

cavity.

Of been made very probable. The difficulty of determin- ringing in the ears, confusion or depravation of sight, of Digestion ing these points arises from the small quantity that can &c.; and if the former symptoms arise to a great height, Digestions

be collested, the largest animals not supplying more than as in the case of overloaded stomach or surfeit, coma,
one ounce or two, at the most. However, the part co or even apoplexy, is frequently produced. In many

agulating on extravasation; the part agreeing with se nervous affections, particularly hysteria and bypochon* Fordyce rum in its qualities; the globular part, wbich in some driasis, in which there frequently takes place astonishing on Dige animals, but not in quadrupeds, exists without giving accumulations of air in the stomach and bowels, the stian.

whiteness to the chyle-alone, or along with sugar, form affections of the head, such as stupor, confusion of 179 Progress of the essential parts of the chyle *

thought, partial blindness, &c. sometimes proceed to the chyle. The compound pulpy matter containing the chyle is such a height, as to threaten, or even sometimes to pro

carried forward from the duodenum through the whole duce, an apoplectic paroxysm. In many cases these affeccourse of the intestines, where it is subjected to the con tions are referred immediately to the head; but are protinual action of the internal wrinkled membrane of the ved, in most instances, to depend on the disordered state bowels, and its nutritious particles, or chyle, selected of the alimentary canal, from the immediate relief proand absorbed by the lacteals that are abundantly distri cured by those remedies which promote the discharge of

buted there, and open their mouths directly within the air, or produce copious evacuation from the bowels. On 130

the other hand, in some diseases, where the head is priPassage

As to the movements of the alimentary canal, the marily affected, as in phrenitis hydrocephalica (water in af food through the

direction of hairs found in the stomach, and the balls the head), the complaint is referred to the bowels, from intestines, of hairs which are thrown "p, would appear to indicate the costiveness or other disordered state of these. The

a circular motion. The intestinal part has a motion daily experience of literary men shows how much intense
similar to that of a worm, and is called the vermicular thought diminishes the digestive powers, and how im-
or peristaltic. Here every portion retains its own mo perfectly studious occupations can be carried on after a
tion, although it be separated from the rest by liga- full meal. The action of the digestive organs is also
tures. The stomach of the polype, the gullets of the considerably influenced by the mind, or the passions,
ruminating kinds, and the cæca, have the motion in We know how readily the appetite may be diminished
different directions at different times; and that observed or destroyed by sudden anger or affliction.
in the alimentary canal of a louse is, when viewed The action of the stomach may even be influenced by
through a microscope in the time of action, amazingly the will. We have known a person who could vomit
rapid; the stimulating causes employed are the food, whenever he pleased; and Dr Darwin speaks of another
the different liquors with which it is mixed, the air, the who had acquired this voluntary command over the in-
nerves where they exist, and a portion of heat. Some verted motions of the stomach and throat, to such a de-
degree of heat is necessary to every process of digestion, gree, as to gain a subsistence by exhibiting these unna-
both in the animal and vegetable kingdom ; what that tural powers to the public. At these exhibitions he was
degree is depends on the nature of the living body; accustomed to swallow a pint of red rough gooseberries,
and is various according to its age, its health, its em and a pint of white smooth ones; to bring them up in
ployments and babits.

small parcels into his mouth, and restore them separately
With respect to the function of digestion in the lower to the spectators, who called for red or white, as they Zoons-
classes of animals, we can say but little. We know that pleased, till the whole were redelivered *.
their food is dissolved in the stomachs of the crustacea, The sympathies that take place between the brain and p. 276.
of mollusca, and of polypes; but whether this process the digestive organs, are easily explained, from consider-
in most insects and worms is any thing more than im- ing the distribution of the great sympathetic nerve, to Plate
bibition, or taking in aliment, which is to undergo lit- illustrate which we have given a figure (fig. 1.) show- CCCCITUL .
tle change, we are uncertain. We know, indeed, that ing its course and distribution from the head through
many insects live on substances which must be dissolved the chest, as far as the stomach.

182 before they enter into the pores of their bodies, and The relations between the digestive and the locomo- Relations that many of them abound in acrid juices, which are tive functions, are not less obvious. Experience shews between well fitted for this solution. It does not appear that how much digestion depends on regular exercise, and digestion

plants possess what may be called the faculty of di how imperfectly it is carried on in the stomach of the and motion. 191 gestion.

indolent and sedentary ; while on the other hand, when Relations The relations between digestion and the functions we the stomach is overloaded, voluntary motion becomes between di; have already considered, especially sensation, are various difficult and fatiguing. Spasmodic contractions of the gestion and sensation.

and important. The sympathies that exist between the muscles, twitchings of the limbs, and similar affections,
head and the stomach, have been long acknowledged. are the common attendants of indigestion, though these
Several affections of the brain are accompanied with may perhaps be referred equally to the nervous as to the
sickness at the stomach, loss of appetite, and indigestion; muscular system.
while on the other hand, the deranged state of the di The principal morbid affections of digestion are, nau- Morbide
gestive organs seldom fails to produce giddiness, headach, sea, flatulence, eructation, rumination (G), vomiting, fections en

mia, roli

heartburn, digestion

man.

(6) That ruminating power which is natural to the quadrupeds of the order Pecora, is sometimes met with in

We have heard of persons who regularly brought up their food into the mouth soon after eating, chewed it over again, swallowed the juices with the saliva, and spat out the more solid parts. In these cases, the rumination

By the

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heartburn, water-brash or pyrosis, loss of appetite, and Mr John Hunter made several experiments to shew Of Absorption. inordinate appetite; for an account of wbich, see the that the veins do not absorb. He conveyed milk, co- Absorption. article MEDICINE. loured with various dyeing substances, or perfumed with

187 musk, into the small intestines of an ass, which was soon CHAP VI. Of Absorption.

after killed. On opening the veins of the intestines, and veins. 184

allowing the blood to separate into serum and crassaAbsorption. We have said that the chyle is taken up from the

mentum, the serum was found neither to be tinged with compound pulpy matter composed of the food and the

the colouring matters, nor scented by the perfume, while animal juices, as it passes through the intestines, by the the coloured milk was evident in the lacteals. That the lacteals. This, however, is not the only absorption that veins, however, do in some cases perform the office of takes place in the animal body. The fluids poured out absorbents, is evident from the speedy depletion of the into cavities by the exhalant arteries, as well as all the

corpora cavernosa penis, after having been distended secreted or exuding fluids, and even the solid materials of with arterious blood; and from a similar depletion that the system, are taken up by the lymphatics, and carried takes place iu the nipple of the female breast.

188 into the circulation; the blood poured out into cells in The principal object in dispute respecting the function By tbe some parts, is evidently absorbed by veins; and, as we of absorption in man and the higher classes of animals, skin,

shall endeavour to prove, an absorption takes place over is, whether the skin possesses the power of absorption. 185 the external surface of the body.

This question, as it is both curious and important, we
Orgaas. What is called the absorbent system, is composed, in shall examine pretty much at large ; and for this pur-

the superior animals, of the lact als, the mesenteric pose we shall avail ourselves of an able paper on the
glands, the thoracic duct, the lymphatics, and the lym- subject, by Dr George Kellie.
phatic glands. For an account of these in man, see It had long been received as an established truth, that
ANATOMY, Part I. Sect. 14. This system, in a great the skin was an inbaling or an absorbing organ, and
er or less degree, is found in all animals, except some that sometimes the inhalation balanced, or even surpas-
mollusca, insects, worms, and zooplytes. See Cuvier's sed, the exhalation of the cutaneous surface; but of late

Leçons, tom. iv. leç. xxiii. and Blumenbach's Compara- this doctrine of inhalation has been called in question,
186
tive Anatomy, chap. xii.

and, in the opinion of many, entirely overthrown. It By lacteals The action of the lacteals and lymphatics is probably has been said, that this absorption neither does nor can and lym much the same, and is exerted in a similar manner. take place on the outside of the cuticle ; that in every phatics. That of the lacteals is to convey the nourishing parts of case of apparent absorption, the epidermis had been in

the food into the circulating system ; that of the lym- jured, or that the matter absorbed had been mechani-
phatics to carry to the same system watery fluids, for the cally forced through it, and brought into immediate
purpose of diluting the blood, and such fluid or solid

contact with the skin.
materials as are useless, or may prove noxious to the sy Haller had asserted *, on the authority of Dessault, * Elementa
stem. The action of the lacteals may be readily seen on that the body acquired an increase of 'weight in the Physiola.
opening au animal killed two or three hours after eating;

giæ, tom. v.

warm bath ; and this augmentation of weight was
and in this way they were first seen by Asellius. They esteemed an experimentum crucis in favour of cutaneous
are then found filled with a milky fluid, while, at other absorption.
times, they are invisible. That the lymphatics are the Experiments, however, have since been made with
principal organs of absorption, is now the general opi- every necessary care, wbich seem to contradict the posi-
nion of all physiologists, though their action in this way tion, and to prove, that the body acquires no additional
can seldom be demonstrated. As, however, it has been weight in the warm bath.
satisfactorily proved, that the veins do not generally ab Seguin, from a great many experiments of this de-
sorb, and as the lymphatics that proceed from parts that scription, concludes, that there is no inhalation, because
contain irritating matters, are often seen inflamed, pro- the body, so far from gaining, always lost some part of
ving that they have imbibed a part of the irritating mat- its weight during immersion, although much less than
ter, there is little doubt that the office of absorption be in the air in equal times t.

+ La Mada longs almost exclusively to the action of the lympha In other experiments again, as iu those of Gerard and

Eclairée. tics.

Currie, there was no increase of weight; but the body

****

3 Q2

p. 88.

was

is to be considered as a disease, depending on the inability of the stomach to propel the solid food into the
duodenum.

Mr Home, in the paper we have already quoted, (N° 161-169), relates a curious instance of habitual ru-
mination in a man 19 years of age, who is blind, and has been an idiot from his birth. He has a very ravenous
appetite, and it is necessary to restrict him in the quantity of his food, since, if he eats too much, it disorders bis
bowels. Fluid food does not remain on his stomach, but comes up again. He swallows bis dinner, which consists
of a pound and a half of meat and vegetables in two minutes, and in about 15 minutes he begins to chew the cud.
Mr Home was once present on this occasion. The morsel is brought up from the stomach with apparently a very
slight effort, and the muscles of the throat are seen in action when it comes into the mouth ; he chews it three or
four times, and swallows it; there is then a pause, and another morsel is brought up. This process is continued for
about half an hour, and he appears to be more quiet at that time than at any other. Whether the regurgitation of
the food is voluntary or involuntary, cannot be ascertained, the man being too deficient in understanding, to give
any information on the subject.

Of was not observed to have lost any thing during immer- ever, cutaneous absorption is denied ; and, when forced or Absorption. sion in the warm bath.

to confess that there are cases where the egesta exceed Absorption. Now, during these experiments, the body was doubt- the ingesta in a much greater proportion than the waste less wasting, by the pulmonary and cutaneous discharges, of the body will explain, and which can only be acand yet the weight of the body either continued un counted for by absorption, they refuse this function to changed; or where a loss of weight was observed, this the skin, and bestow it most liberally, and, in so far as was constantly less, greatly less, tban is experienced du we know, most gratuitously, on the lungs. We are ring the same interval in air. And we might be incli- not entitled, in return, to deny the reality of pulmonary ned to infer, from a truth so general, and so well ascer- absorption, but we may surely be allowed to urge, that tained, an argument in favour of absorption.

there is no proof that the only inhaling organ is in the It might be argued, that the loss of weight amounts lungs ; and there is none against the possibility of cutato little or nothing, because, during immersion, the bo neous absorption. dy acquires more by inhalation than it does or can do in Is it not, on the other hand, proved, by the experithe air ; that the loss by the pulmonary and cutaneous ments of Seguin and Lavoisier, that the exhalation discharges are counterbalanced, or nearly counterbalan- greatly exceeds the absorption by the pulmonary system? ced, by the increased absorption.

And if this is always the case, we cannot explain by Those, however, who deny absorption, will not allow pulmonary inhalation alone, why the egesta should, in us the advantage of this argument. They tell us, that

some cases,

exceed the ingesta in a much greater prothe exhalation by the skin and lungs is diminished, portion than the waste of body will account for. which sufficiently explains why the body loses less in the We now proceed to examine another class of experiwarm bath than in air. But that the accustomed dis- ments, much insisted on by those whe deny cutaneous charges are suppressed or diminished in the warm or te. absorption; we mean those experiments performed by pid bath, is, we apprehend, far from being proved; immersing a part of the body in solutions of active drugs, and, till this proposition is made good, the argument the absorption of which should be indicated by their uagainst cutaneous inhalation cannot be securely main- sual effect on the system. tained.

Seguin made numerous experiments of this kind with One of Dr Currie's cases deserves farther considera- solutions of muriate of mercury (corrosive sublimate), on

tion. We allude to the case of dysphagia, published by syphilitic patients. And we are informed, that in cases * Medical this gentleman *, in which Mr M. the subject of the where the epidermis was perfectly sound, neither the Report, case, was several times immersed in a warm bath of known effects of mercury on the body, nor any amelio

milk and water, and was weighed when taken out. ration of the venereal symptoms, was ever observed. p. 227.

Mr M. it is true, gained no weight while in the warm He also immersed his own arm in a solution of two
bath : but the loss continually going on in the air was, drams of the mercurial muriate in ten pounds of water.
as in other trials, suspended during the immersions. Be- At the temperature of 10 and 28° Reaumur, no part of
sides, he also expressed great comfort from the bath, the salt was missing at the end of the experiment; but
with abatement of thirst ; and, subsequent to the daily when the bath was at 18° of the same scale there was a
use of it, the urine flowed more plentifully, and became loss of one or two grains of the muriate in the bour,
less pungent. An observation, precisely similar, is made though the quantity of fluid was pot diminished.
by Mr Cruickshank. A patient of mine (says Mr The explanation given by Seguin of this unexpected
Cruickshank), with a stricture of the æsophagus, re result is curiously ingenious, but embarrassed, and in-
ceived nothing, either solid or liquid, into the stomach consistent.
för two months; he was exceedingly thirsty, and com At the temperature of 12°, he observes, the exhalants
plained of making no water. I ordered him the warm are in a state of contraction, and their orifices nearly
bath for an hour, evening and morning, for a month; closed. When the beat again is raised to 26°, the exha-

his thirst vanished, and he made water in the same man lation is so rapid, that nothing can enter the vessels from # Cruick

ner as when he used to drink by the mouth. (H) +. without; but at 180 of temperature, the orifices of the

But to return to the case of Mr M Dr Currie exhalants are sufficiently relaxed, and the exhalation at the Absor dents.

himself remarks, that the discharge by orine alone ex the same time so conveniently languid, that the solution
ceeded much in weight the waste of bis whole body; rests quietly in contact with the matter of perspiration
and it cannot be doubted that the discharge by stool and in the mouths of the exhalants, where it is somebow or
perspiration exceeded the weight of the clysters.-Thus other decomposed; a part of the salt leaving the water
it appears, that the egesta exceeded the ingesta in a pro of solution, and combining with the perspirative matter,
portion much greater than the waste of his body will ex with which it is carried into the system *. Carried into * La Med
plain. How is this accounted for, Dr Currie asks, un. the circulation by the exhalants ! Is not this a plain ac-Eclairis,
Less by cutaneous absorption ?

knowledgment of the reality of inhalation ?
That the excess of these discharges above the ingesta one case substances may tbus be carried into the circu-P. 238.
and total waste, can be accounted for by absorption lation, why not in many others ?
only, was indeed an irresistible conclusion. Still, how Surely if the weight continues undiminished, in cir.

cumstances

first cdit.

shank on

But if in tom. iii.

(1) That thirst may be allayed by immersion in water, is fully proved by the experience of shipwrecked mariDers, who, when obliged to take to their boats with very little fresh water, frequently have recourse to bathing in the sea, or covering themselves with a shirt wetted in salt water, and thus quench their thirst, nearly as well as if they had drunk fresh water.

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