_Health Primers._
[Illustration]
Health Primers.
EDITORS.
J. LANGDON DOWN, M.D., F.R.C.P.
HENRY POWER, M.B., F.R.C.S.
J. MORTIMER-GRANVILLE, M.D.
JOHN TWEEDY, F.R.C.S.
BATHS AND BATHING.
CONTRIBUTORS TO THE SERIES:
_G. W. BALFOUR, M.D., St. And., F.R.C.P. Edin._
_J. CRICHTON-BROWNE, M.D. Edin., F.R.S. Edin._
_SIDNEY COUPLAND, M.D. Lond., M.R.C.P._
_JOHN CURNOW, M.D. Lond., F.R.C.P._
_J. LANGDON DOWN, M.D. Lond., F.R.C.P._
_TILBURY FOX, M.D. Lond., F.R.C.P._
_J. MORTIMER-GRANVILLE, M.D. St. And., F.G.S., F.S.S._
_W. S. GREENFIELD, M.D. Lond., M.R.C.P._
_C. W. HEATON, F.C.S., F.I.C._
_HARRY LEACH, M.R.C.P._
_G. V. POORE, M.D. Lond., F.R.C.P._
_HENRY POWER, M.B. Lond., F.R.C.S._
_W. L. PURVES, M.D. Edin., M.R.C.S._
_J. NETTEN RADCLIFFE, Ex-Pres. Epidl. Soc., &c._
_C. H. RALFE, M.A., M.D., Cantab., F.R.C.P._
_S. RINGER, M.D. Lond., F.R.C.P._
_JOHN TWEEDY, F.R.C.S._
_JOHN WILLIAMS, M.D. Lond., M.R.C.P._
LONDON:
HARDWICKE AND BOGUE, 192, PICCADILLY.
1879.
LONDON:
PRINTED BY WILLIAM CLOWES AND SONS, STAMFORD STREET
AND CHARING CROSS.
CONTENTS.
PAGE
THE PHYSIOLOGICAL ACTION OF BATHS 5
THE VARIETIES OF BATHS 20
BATHING LOCALITIES 45
THE USES OF BATHS 68
A VISIT TO A BATH 83
BATHS AND BATHING.
CHAPTER I.
THE PHYSIOLOGICAL ACTION OF BATHS.
Since the influence of baths is exerted primarily upon the skin, and
through the medium of the skin, upon the deeper-lying tissues and
organs of the body, it is an absolute necessity for the reader at the
outset to be made aware of the structure of the skin and its functions,
as well as the relations which it bears to deeper-lying organs.
If the skin, say of the thumb, be looked at with a lens of moderate
power, its surface is seen to be arranged in ridges and furrows, like a
ploughed field; and at frequent intervals along the ridges are little
depressions, which are known as the pores of the skin. These pores are
the openings of the sweat ducts, and it is through these pores that
the perspiration exudes. They are exceedingly numerous, and it has
been calculated that there are as many as 2,800 to every square inch
of surface, or about seven millions of them altogether. The ridges are
seen to be divided into a series of minute hillocks, or _papillæ_,
which are arranged in lines. These papillæ are the organs of touch, and
are probably as numerous as the pores. They contain in their interior
either loops of blood-vessels or nerve-endings.
These nerve-endings in the papillæ are of three kinds, which are
readily distinguishable, and are known as tactile corpuscles, pacinian
bodies, or end bulbs, according to the form which they take. Between
the superficial and deep layers of the skin, the so-called cuticle and
cutis, is a layer which partakes somewhat of the character of both.
This is called the rete mucosum, and it is here that the pigment, found
in the skin of the negro and in certain parts of the skin of white
races also, is located.
Beneath the skin, in the subcutaneous tissue, are situated the
sweat-glands, which are microscopical bundles of tubing, having one end
running through the skin to terminate in the pores. These tubes are, or
rather would be, if straightened out, about a quarter of an inch long;
and it is estimated that the length of them in the entire body is about
28 miles! They pass through the upper layer of the skin or cuticle
spirally, so that, although it is an easy matter for fluid to pass
_out_, the passage in the opposite direction is by no means so easy.
Each sweat-gland is plentifully supplied with blood-vessels, and is
surrounded by a thin muscular coat, which is presumably able to exert,
by its contraction, a certain amount of pressure, and so drive the
secretions of the gland onward towards the pore, or external aperture.
The hair follicles, like the sweat-glands, are situated in the
subcutaneous tissue. They are hollow receptacles, from the bottom of
which the hairs grow. Alongside of each of these hair follicles is a
pair of glands, called the sebaceous glands, which provide that small
quantity of natural grease with which our hair is supplied. These
glands resemble little bunches of grapes. The hair follicles are also
furnished with a couple of small muscles, which, by their contraction,
can cause a sensible erection of the hair. In certain parts of the
skin there are glands which furnish a special odorous secretion.
These are most plentiful in the arm-pits and between the toes. In the
skin itself, and immediately beneath it, is a network of “lymphatic”
vessels, whose function, it would seem, is mainly to drain the tissue
of waste products. These vessels run towards the “lymphatic glands,”
which, when enlarged, are often recognisable at the side of the neck,
and which are very generally distributed throughout the body. In
certain parts of the skin are special cells containing pigment.
Thus we see that the skin, which to the casual observer is an almost
structureless membrane, is in reality a most complex and elaborate
organ, richly supplied with blood-vessels, lymphatic vessels, and
nerves, having its millions of papillæ and pores, and its miles of
sweat-ducts. The hair follicles, with their sebaceous glands and
muscles, are also to be reckoned by the million, and its odoriferous
glands and special pigment-bearing cells probably by the thousand.
What are the various uses of this elaborate organ? In the first place,
it serves as a protection to the softer parts beneath. Secondly, it
serves to regulate the temperature of the body, by preventing, on
the one hand, the too rapid radiation of the natural heat, and, on
the other, by providing a very large surface for the evaporation of
the constantly exuding perspiration, it prevents the overheating of
the body. Thirdly, it is constantly removing from the body certain
effete materials. These are the scales of the cuticle (which we remove
whenever we wash and rub the surface), the perspiration, and the
sebaceous, or greasy secretion. The amount of sweat varies immensely;
it may be almost nil, or as much as a pint in an hour. The secretion
of sweat is influenced by the temperature of the air, by exercise,
by the drinking of fluids (especially warm fluids), and notably by
the emotions. There can be no doubt that the secretion of a certain
amount of sweat is necessary for perfect health; and it is the common
experience of all that the checking of perspiration is very liable to
be followed by dangerous internal congestion.
It has been demonstrated on some of the lower animals that, if the skin
be shaved and varnished, death speedily ensues. This has been spoken
of as a sort of cutaneous suffocation, death taking place owing to the
charging of the blood with matter which should have been removed by the
skin. It has been asserted, however, that death is due to cold in these
cases; and it has certainly been demonstrated that animals so treated
live much longer provided they be kept warm by a layer of cotton wool.
Sometimes the skin is superficially destroyed by accidental burning or
scalding, and it is well recognised that a burn or scald is dangerous
to life in proportion to its superficial extent, rather than to its
depth or severity.
The blood-vessels of the skin vary much in size under different
circumstances, and the different degrees of pallor or redness of the
skin are due to the condition of these superficial blood-vessels. The
phenomenon of blushing is well known; and this should serve to remind
us that the emotions can not only influence the amount of perspiration,
but the size of the cutaneous blood-vessels. The intimate relations
existing between the skin and the great nerve-centres should never be
lost sight of.
The cutaneous blood-vessels enlarge in certain fevers, as scarlet-fever
and measles; they can be made to enlarge also by the application
of warmth, or irritants, such as mustard, or the stroke of a whip.
Contraction of the blood-vessels is most marked in conditions of fear,
or as the result of the prolonged application of cold.
Not only have the nerve-centres a great influence on the skin, but the
skin is capable of exerting a great influence on the nerve-centres.
This is not to be wondered at, when we bear in mind the myriads of
nerve-bearing papillæ with which the skin is beset. When the soles
of the feet are tickled, the legs are involuntarily moved; and when
the arm-pits and sides of the chest are tickled, loud laughter is the
result. These two phenomena are examples of what is known as _reflex
action_, i.e., the tickling produces an effect upon the nerve-endings
in the skin, and this effect travelling to the nerve-centres (the
spinal cord or brain) is _reflected_ to the muscles, and produces
movement of the leg or laughter. When the body is suddenly immersed in
cold water, a not uncommon result is a shivering and a chattering of
the teeth; and when cold water is sprinkled on the forehead or chest,
deep inspiration and a catching of the breath is produced. These are
examples of “reflex movements,” due to impressions made upon the nerves
of the skin; and since many of the results of bathing are undoubtedly
due to this kind of reflex action, it is very important to bear it
constantly in mind. The connection between the nervous centres (the
brain and spinal marrow) and the skin is shown also in the occurrence
of what is known as goose skin, or _cutis anserina_, which is caused
not only by the application of cold to the surface of the body, but
even more readily by the mental states which make the “Hair of our
flesh stand up.” The rationale of this phenomenon is the contraction
and shortening of the little muscles which we have seen to be in
intimate relationship with the hair follicles. There can be no doubt
also that the pigment cells, which are scattered thinly throughout our
skins, are subject to the control of the nervous centres, and it is
well known that the tint of the complexion will sometimes vary with
emotional states, as it certainly does with physical states. These
considerations are sufficient to show that the skin plays a most
important part in the animal economy, as a protective, a secreting, a
vascular, and a nervous organ.
An all-important point to be determined with regard to the skin is
its power of _absorption_--that is, its power, if any, of allowing
substances to pass through it, and so reach the interior of the body.
It is well ascertained that, if the surface of the skin be broken,
absorption takes place with great rapidity, and that even when the
skin is not broken, it is comparatively easy to get absorption of
certain matters, such as mercurial ointment or extract of belladonna,
provided they be applied with a certain amount of friction. We saw that
the ducts of the sweat-glands perforated the skin spirally, and the
friction has the effect of opening the mouths of these little ducts,
so that the greasy or sticky preparation gets lodged within them and
absorbed.
It has been proved with tolerable certainty that gases, such as
carbonic acid and oxygen, are capable of penetrating and permeating the
skin in small quantities, but it is extremely doubtful if water is ever
absorbed through the skin. It has been attempted to settle the question
by weighing the body before and after a prolonged immersion in the
water, but such experiments are so beset with fallacies that they are
almost worthless. The fact that shipwrecked sailors are in the habit of
successfully lessening their thirst by immersion of the body in water,
or by wetting their clothes, is well known, but this effect may be due
to the arrest of the cutaneous evaporation, or by an effect upon the
nerves.
At all events it seems safest, in the present state of our knowledge,
to assume that water is not absorbed through the skin; or if it be,
that it is absorbed in such extremely small quantities that the effect
of baths can in no sense be due to the absorption of the water in
which the body is immersed. As to the absorption of the various salts
contained in sea-water or mineral waters, there is no evidence whatever
that these are ever absorbed even in the most minute quantities. If
the salt dissolved in sea-water were absorbed through the skin, it is
tolerably certain that sea-bathing, far from being the luxury which
it is, would be regarded as a highly dangerous and most unpleasant
practice.
Baths of all kinds serve, or may be made to serve, as vehicles for
temperature, and by their aid we are enabled to surround the body
with a temperature which is different to its own. Before we can fully
understand the effect of hot and cold baths on the economy, it is
necessary to enter into some discussion of the nature and source of
the natural heat, of the body. The natural heat of the human body
is between 98° and 99° of Fahrenheit’s scale; and this temperature,
roughly speaking, is uniformly maintained by the healthy body under all
the varying circumstances to which it may be subjected. In the arctic
regions, and in the tropics the temperature of the body rests at 98·6°;
or, if variations occur, they are so slight in amount as to be hardly
noticeable. In a cold atmosphere, therefore, the body has the power of
maintaining its heat; and in a warm atmosphere it is equally able to
maintain its coolness. This is a remarkable fact, and is due to the
power possessed by the human body of adjusting the production and loss
of heat. Heat is produced in the body by the combustion of food and
tissues, exactly as heat is produced in a fireplace by the combustion
of coal. The amount and rapidity of this combustion necessarily varies
with the amount and nature of the food consumed and the activity of
exercise and other vital processes. The most active tissue in the body
is the blood; through its agency most of the combustion processes
are carried on, and by its rapid circulation to all parts of the
body the most distant points of the human frame are kept at the same
temperature. The temperature of the blood is due to the amount of
combustion taking place in the tissues, and the amount of combustion
taking place in the tissues is due to the amount and energy of their
blood supply, which last depends upon the force of the heart’s action
and the size of the blood-vessels which have the power of contracting
and dilating, and which are subordinated to the regulating influence of
the nerve-centres. If that part of the nerve-centres (the upper part
of the spinal cord) which controls the size of the vessels be injured
or destroyed, the combustion processes going on in the body seem to
get beyond control and the temperature may be dangerously increased or
decreased, the exact reason of one or the other phenomenon not being
known. The limits of body temperature which are compatible with life
are not very wide; for if the temperature rise to 109° or sink to 76°
death will inevitably result, and a rise or fall of 7° from the natural
temperature is decidedly dangerous. Seeing how narrow are the limits of
temperature within which life is possible, we cannot but be amazed at
the marvellous arrangements for maintaining the normal level of animal
heat. The body is cooled by the evaporation going on from the lungs; by
the more important evaporation going on from the skin (every one who
has covered a portion of the skin with spirit and has encouraged its
evaporation by blowing upon it knows practically the cooling effect
of evaporation), and by the radiation of heat from the surface of the
body, and the conduction of heat from the body by things in contact
with it.
The _immediate_ effect of a cold bath is to chill the _surface_ of
the body, the temperature of which, as tested by a thermometer, may
fall several degrees. At the same time there is produced a pallor of
the surface and goose-skin. While the surface is cooled, however,
the blood itself undergoes an increase of temperature, due to an
increase of the combustion processes going on in the body, of which
we get additional evidence in the increase of the rate of the pulse
and respiration, and an augmented discharge of carbonic acid from the
lungs. There is a sudden sense of chilliness, and this impression, made
upon the nerves of the skin, produces, by its action on the brain and
spinal cord, some slight mental excitement and shivering of the limbs.
After the bath has been continued some little time the temperature of
the blood falls (sometimes as much as three or four degrees), the pulse
and respiration get slow, the shivering gives place to lassitude, and
the mental excitement to listlessness. On removal from the bath the
phenomenon of “reaction” sets in. The vessels of the skin enlarge, the
chilliness gives place to warmth, and the feeling of uneasiness is
succeeded by a sense of comfort. This reaction follows most quickly
when the bath is of short duration, and when its effects are suddenly
induced. The shorter the bath the less is the ultimate depression of
the temperature of the blood. The shorter the bath the greater is its
power of _stimulating_ function; the longer it is continued the greater
is the effect of _cooling_.
The effect of a _warm_ bath is to raise slightly the temperature of the
surface and the temperature of the blood. The pulse and respiration are
both quickened, and the escape of carbonic acid from the lungs is also
increased. The blood-vessels of the skin get dilated, and the surface
is reddened in proportion to the heat of the water. Warm baths of a
moderate temperature can be borne for a longer time than cold baths;
but if the temperature be too high, and the bath too long-continued,
faintness is liable to occur. On removal from the hot bath the skin
is in a very delicate and susceptible state, and the vessels are
liable to “re-act” in the direction of extreme contraction, in which
case dangerous internal congestion may occur. If, however, the skin
be protected, and the patient be placed in a warm room, or in bed,
a violent perspiration will ensue. In the cold bath the muscles are
liable to become stiff; but in the warm bath a stiff and fatigued
muscle will resume its suppleness. After a hard day’s hunting a warm
bath is a well-known and agreeable luxury.
The phenomenon which is popularly known as “reaction,” and which occurs
after both hot and cold baths, is a most remarkable one, and seems
to show that our bodies resent any interference with their function.
Thus experiments have shown that if the temperature of a healthy man
be raised or depressed by any artificial means, such as hot or cold
baths, the subsequent reaction in the direction of the depression or
exaltation of the temperature is such that the mean temperature of
health is accurately maintained. A German observer, Jurgensen, found
by a series of accurate observations on a patient who submitted to
a series of baths of a temperature of 50° Fahr., each bath lasting
twenty-five minutes, that notwithstanding the rapid abstraction of
heat, which gave rise to shivering, lasting for several hours, the
diminution of bodily temperature which occurred during the bath was
followed, after an interval of four or five hours, by an elevation
which precisely compensated it, so that the mean normal temperature was
maintained in spite of the interference of the physiologist.
It will have been observed that the ultimate result of both hot and
cold bathing, if conducted in moderation, is about the same, viz., an
increased circulation of blood through the skin. In both cases also,
the combustion going on within the body is increased, as evidenced by
the escape of an increased quantity of carbonic acid from the lungs.
In the case of the cold bath, this increased combustion is due to the
stimulating effect of the cold water, while in the hot bath it is due
to the artificial heat facilitating the natural combustion processes
of the body. The effects of the hot and cold bath upon the combustion
processes going on in the body may, not inaptly, be compared to the
effect produced upon a furnace by the hot and cold blast, both of which
encourage combustion and increase the heat given off by the furnace;
but the hot blast so facilitates combustion that the same work is done
by its aid, with an expenditure of 2-1/2 tons of coal, that is done
by the cold blast with an expenditure of 8 tons of coal. If we want a
fire to burn well, we have several courses open to us; the first is to
poke it, which may be regarded as simple stimulation; the second is to
supply it with a cold blast, in which case we supply large quantities
of oxygen, but at the same time counteract the heating effect by
the coldness of the blast. By employing a hot blast, the combustion
is facilitated without any counteracting chilling. By each of these
methods we hasten the ultimate extinguishing of the fire, unless
fresh fuel be added. The employment of the hot blast entails the most
economical use of the fuel.
It has been said, with regard to the use of baths, that _cold
stimulates, but heat facilitates function_. “Between the two
therapeutic opposites,” says Braun, “a similar relation exists, as
between winter and summer life, and between sea and mountain air.
The physician who has, to a certain extent, acquired an insight into
the diseased side of mankind, divides the chronically sick into two
groups, the one consisting of individuals whose organism has sufficient
capital to afford the strong reaction required, the other consisting of
persons needing nice management, and whose own power cannot be exposed
to any great demand. For the one there is the system of exercise,
cold treatment, cold baths, sea baths, and sea air; for the second,
indulgence, warm treatment, warm climate, warm baths, mountain air.”
Seeing that both hot and cold baths increase the natural combustion
of the body, it will be evident that persons undergoing a course of
treatment by either method should be exceedingly careful that during
the progress of their course of treatment the best fuel only is placed
on the human furnace. They should eat the simplest and most nutritious
food, and breathe nothing but the purest air.