By L. L. McArthur, M. D.
Treasurer Medico-Legal Society, Chicago: Attending Physician Michael
Riess and Mercy Hospitals, Chicago.
[Abstract of a paper read before the Chicago Medical Society on January
4, 1886.]
The object of clothing should be the promotion and maintenance of good
health, together with a feeling of well-being under all atmospheric
conditions.
Consideration of the subject naturally sub-divides itself into:
I. Materials.
II. Texture.
III. Form of clothing.
Chief among the materials used for clothing in the order of their
respective merits are linen, cotton, silk, and wool, the latter being
the best.
A few words as to these materials in the raw state:
Linen conducts heat better than cotton, silk or wool. It absorbs
moisture and does not shrink. Cotton, also a vegetable fibre, which is
hard, durable and does not shrink, has serious objections, in that it
is very non-absorbent of moisture. It does not conduct heat as well as
linen, but more rapidly than silk or wool.
Silk, an animal product, consisting of fine, smooth round fibrillæ,
having been in the liquid condition before leaving the body of the
silkworm, possesses no central canal, and no oily coating. It is
quite a good absorbent of moisture, ranking next to wool. At ordinary
temperature it always contains between 9 and 12 per centum of moisture.
In its sale or purchase, account is taken of the amount of moisture in
order to protect the purchaser from paying silk prices for water.
Wool, the fleece of sheep, an animal fibre, whose function in nature
has been two-fold, the protection from cold, and an aid to evaporation
of cutaneous moisture, is admirably fitted as a material for clothing.
It permits but slow radiation of heat, and absorbs moisture better than
any other clothing material. It does this, according to Parkes, in two
ways: 1st. By interposition between the fibres. 2d. By penetration into
the central canal. His experiments led him to believe its hydroscopic
powers double in proportion to its weight and quadruple for surface, as
compared with cotton or linen. Perfectly dried wool has the power of
absorbing 50 per centum, by weight, of water. Under ordinary conditions
it contains 12 to 18 per centum.
Other things being equal, then woolen fabrics will best prevent too
rapid radiation of heat; silk next, cotton third, linen fourth.
Wash-leather, buckskin and chamois-skin need not be considered, for
one or all of the following reasons: Expense, poor provision for
evaporation, poor washing qualities.
As absorbers of moisture, rank, respectively: wool, silk, linen and
cotton.
_The advantages of cotton over wool lie in its cheapness and
non-shrinking qualities. If properly constructed, however, the
advantageous properties of wool can be utilized without the shrinking
by using a cotton framework, into the meshes of which the loose, raw
fleece is worked._
That fabric will be best adapted for health, which combined with
greatest porosity, possesses the least (a) conductivity, (b) greatest
hydroscopic power, and (c) best shape.
By porosity is understood the freedom with which air can pass through
the interstices of a fabric. Pettenkoffer's practical demonstrations
with the following cloths, shows that if heavy flannel be taken as
permitting 100 parts of air to pass, linen permitted 60.3 or 60 per
centum; lambskin 50.7 or 50.7 per centum; silk fabric, heavy, 14.4 or
14.4 per centum; glove-leather 1.5 or 1.5 per centum.
The conclusion follows that porosity does not injure the powers of
preventing radiation (it even increases it) for flannel, admittedly the
warmest clothing, permits the freest circulation of air.
In consequence of the fact of a fabric's possessing great porosity,
it contains in its interstices what might be called "residual air."
Whether gases possess conductivity is open to discussion, but this is
certain, that such power is very small. Could we by any means envelop
the body in a layer of stationary air, we could reduce the heat-loss to
a minimum. A striking example of the poor conductivity of _stationary
air_ is related by Dr. Kane, the Arctic explorer, who found that
on perfectly still days they could withstand, without suffering, a
temperature of-70 F.,[A] with ears and hands exposed, but the moment a
breeze sprung up it became necessary to seek immediate shelter.
[A] 70° F, below Zero.
Although impossible to perfectly accomplish this, (_i. e._, the
surrounding of body in a stationary envelope of air), that cloth or
fabric which most nearly approximates this, other things being equal,
will prove itself the warmest as well as best adapted for evaporation
of cutaneous moisture. Such a nearly stationary air occurs naturally
in the various pelts, and although in many the integument is visible
beneath, yet they can withstand the most rigorous weather. Thus
Krieger's experiments with tin cylinders containing hot water with two
coverings of different materials, between which an interval of 1/8
to 1/4 inch was left, proved (after subtracting the amount due for
conduction) the impediment to radiation by the second layer to be,
_viz_: linen, 32; silk, 32; flannel, 29.
Thus showing that the stationary air, rather than the material out of
which the second layer was made, was the main factor in preventing
radiation.
He then experimented with single and double layers of the same material
surrounding these cylinders, obtaining the following instructive
results; the numbers representing the proportionate loss of heat
through double to single layers, the losses through the single ones
being taken at 100:
Double Stuff, ("Doppel Stoff") Fleece-lined cotton 69-76
Buck-skin 74-86
Flannel 86
Home-spun linen 91
Stout, extra heavy silk 94
From these results the conclusion is obvious that the substance and its
weight are of less consequence, where _radiation_ is in question, than
its texture and volume. Believing that the explanation was due to the
"residual air," experiments have been made with loose wadding, noting
the rapidity of fall of temperature, on compressing the same wadding,
when the fall was far more rapid.
Again, the loss of heat through a rabbit's fur being taken as 100, when
shorn of its hair it rose to 190; and further destroying its porosity
by a coating of gum-arabic, it rose to 296. (Dict. Hygiene.)
By greatest porosity best provision is made for the evaporation of
perspiration, the quantity of which varies greatly under different
conditions. In a day of rest the amount as determined by Seguin and
Voit is 900 grams (about 1 quart). During exercise it may increase to
quantities incredible, were the figures not furnished by the best of
observers. For example: Dalton mentions its increase to 380 grams per
hour! and Dr. Southwood Smith has seen it rise to 1,600 grams per hour
during violent exercise in a heated atmosphere! Now, if a clothing
possesses no porosity, _e. g._, the mackintosh, and rubber clothing
generally, even without exercise, there would collect somewhere beneath
it a quart of water, but if exercise be indulged in, the quantity
may become large indeed; particularly after the atmosphere beneath
has been surcharged with vapor, and evaporation ceases to occur from
the surface, and with it the grateful cooling process. The French
Government has not permitted its introduction into its army for such
obvious reasons. Of course, for a short time during a shower they
may and do prove useful; but I am convinced that many have incurred
most serious injury, even death, by throwing off the rubber clothing
after the inner clothing had become permeated with moisture, when the
chilling, incident to the sudden increased evaporation, has resulted in
some acute inflammation.
Moreover, the evaporation of the normal cutaneous moisture (with that
of the lungs) requires 750 heat units or one-fifth of all the heat
produced in the system. (Dalton.) Conservation of part of this loss
contributes an equivalent amount of force to the organism, since heat
and force are interchangeable terms. _This can be done._
Under normal conditions evaporation of perspiration occurs in the
"insensible," _i. e._, vapor state, but change of these conditions
(increased heat, and moisture in the atmosphere, increased exercise,
etc.,) causes it to collect upon the integument in the visible or
sensible state, and unless conducted away, may chill the body.
Prevention of such condensation will avoid such dangerous and
deleterious influences. The cause of condensation is a lowering of
the temperature. _We have simply to maintain its temperature until at
a perceptible distance from the body. This can be accomplished by a
layer of loose wool, such as is hereafter described. The "residual air"
having been once raised to the body temperature, it remains so, and the
vapor does not assume the liquid state until meeting with the chilling
influences in the outer layer of cloth._
Finally, bodies passing from the gaseous to the liquid state emit the
heat--latent heat--which was essential to their assuming the gaseous
condition. This occurring in the case of perspiration in the cloth
interstices increases by just so much their warmth, in other words
lessens the demand for heat production.
Before leaving the subject of texture, note should be made of the
importance of its being of a loose nature. _However great the
hydroscopic power of a material in the raw state, if it be tightly
woven that power is greatly diminished, or even quite destroyed. Hence
the advantage of loosely knitted over tightly woven goods._
Important indeed is the proper fitting of clothing. However good the
materials they may then not accomplish their purpose for the following
reasons:
I. By close application to the skin certain materials acting as
cutaneous stimulants, maintaining an active equable circulation. Wool
possesses this property most markedly; even in some delicate skins
proving an irritant. A very marked increase of oily matter is excreted
over these areas where oil-glands exist in greatest abundance, _i. e._,
mesial line of thorax, in front and behind; thus improving the
flexibility of the skin.
II. By fitting neatly, chambers of air heated by the body are not
with every change of position of the wearer forced out, as occurs in
illy-fitting clothing. Upward currents of air naturally occur, and if
permitted to exist carry off large amounts of caloric. Simple attention
to these two facts reduced the death rate of the Wurtemburg Army Corps
from 3.22 to 1.64, as compared with the other departments of the German
Army.
The general application and advantages of such an ideal clothing to
diseased conditions, it is needless for me to describe to a body of
medical men; but particular references ought to be made to rheumatism
and nephritis, ("kidney troubles.") To the former, because best
provision is made for cutaneous elimination (always acid!) so essential
in that disorder, in which there is so marked a diminution in the
alkalinity of the blood; to the latter because sudden congestions are
obviated in an organ already overworked, by preventing sudden chilling
of the surface.
_It only remains for me to call your attention to my accidentally
finding such a clothing upon a patient of mine (Mr. Jaros), and the
tests to which I have put it._
_He described its history and manufacture as follows_:
"_While suffering from an attack of rheumatic sciatica in the Harz
mountains, following a peasant's advice, I enveloped myself in loose
lamb's fleece which he provided, and I experienced speedy relief. On
reaching Berlin I consulted Chief Councillor-of-Health, Dr. Abarbanell,
who advised me to have constructed some underwear with a fleece lining.
I sought a weaver and had some underwear knitted, into the meshes of
which were worked, "by hand," during the process of knitting, layers of
loose lamb's wool._"
Now, gentlemen, this device was a particularly happy one, in that all
the requirements of a truly hygienic wear are provided for.
_Porosity, warmth, absorbent powers and elasticity. With advice he
set to work and perfected a modification of the knitting machine
which incorporated into the meshes of the cloth loose lamb's wool.
The samples presented speak for themselves as to its success. By the
use of such a fabric, perspiration (unless excessive indeed) remains
in the insensible state until it meets with the cooling influences
externally in the cotton framework, the integument remaining dry, while
the cotton back, as well as the linen shirt over it, may be "wringing
wet." Exposure to cold draughts with such a suit does not chill the
integument because the sudden increased evaporation occurs at a
distance from the skin, and is separated from it by a layer of wool._
_To test the soundness of the theory I submitted myself to a
temperature of 115° F., under as nearly as possible the same
atmospheric conditions, with the three chief winter suitings, and
obtained the results in table below:_
====================+==============+============+============
| | "Nonotuck" |
| _Jaros | Silk |
| Hygienic | Suiting, | Cartwright
| Wear._ | heavy. | & Warner's
--------------------+--------------+------------+-------------
Weight after | 8,020 | 7,867 | 10,840
" before exposure | 7,010 grs. | 7,140 | 9,600
Difference | 1,010 grs. | 727 grs.| 1,240
Degree of absolute | | |
dryness of air | 61,827 | 77.32 | 69.947
Temp, dry bulb therm| 115° F | 113° F | 116°
Temp, wet bulb therm| 9° | 83° | 88°
--------------------+--------------+------------+--------------
|_Warm but not |Cooler than |Sticky,
|sticky; outer |other wear; |clammy;
Sensation |surface damp; |sticky; skin|wet
|skin dry where|damp; |through;
|wear touches; |comfortable.|uncomfortable.
|comfortable._ | |
====================+==============+============+==============
_From these experiments it is to be seen, that of all the perspiration
exuded, the silk retained (by a small amount) the least; the hygienic
wear the next, and the English woolen goods the most. Note, however,
must be taken of two facts concerning the experiment with the silk
clothing._
_1st. The temperature was 2° F. lower than when testing the hygienic
wear, and 8° than the English goods. Hence less perspiration was thrown
out._
_2d. There was a difference of 15.5° of absolute dryness of the
atmosphere, hence evaporation took place more rapidly from the silk
goods in the dryer atmosphere. The barometer remained almost stationary
during the three days of observation._
_On emerging from the hot room into one of a temperature of 70° F.,
an immediate chilling was felt with the silk goods; while the English
gave a sensation of moisture and cold. The chilly sensation was not
experienced with the woolen-lined hygienic wear._
_CONCLUSIONS._
_1st. That fleece-lined goods are warmest._
_2d. Permit at least equal evaporation with the silk._
_3. Guard against sudden chilling of the body._
_4th. Are cheaper than silk and as cheap as Cartwright & Warner's._
_5th. Are particularly indicated in rheumatism and kidney disease._