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Germs D USTand Disease

" THF URIGHT - . N G PARTI- "

y4NDI\EW SmAI\T M.D

"the bright ray reveals the floating particles."

DESCRIPTION OF GERMS.

1. Rinderpest Germ. Discovered, delineated, and published by the Author

in September 1865.

2. Relapsing Fever Germ. Discovered by Obermeicr in \868.

3. Anthrax Gefvi ( Wool- Sorters' ). Discover'U by Koch about 1874.

4. Vaccine Germs. ( Probably analogous to SmaJl-Pox Germs not yet dis-

covered.) .Sanderson, 1869.

5. Filan'a .Sanguinis. A Germ found in the blood of the affected person

during night, but absent during day. Manson, 1 88 1 .

6. Typhoid Fever Germ. Eberth — diseovered about 18S0.

7. Consumption Germ. Koch — recently discovered.

GERMS, DUST, AND DISEASE :

^wo Cbapters in ©ur Xife Ibistor^,

ANDREW SMART, M.D., F.R.C.R

EDINBTTEGH.

EDINBUEG H:
MACNIVEN AND WALLACE.

MRS TRAYNER,

THROUGH WHOSE ENLIGHTENED, ZEALOUS,
AND PHILANTHROPIC INTEREST IN THE PEOPLE, THE
EDINBURGH HEALTH LECTURES WERE FOUNDED, THESE PAGES
ARE RESPECTFULLY DEDICATED BY

THE AUTHOR.

PREFACE.

The Author, in yielding to the wish conveyed to him to repub-
lish, in their present form, the two accompanying Lectures, does
so, in the hope, that the attainment of the object contemplated
by them will thereby be furthered.

The first Lecture, delivered under the title of " Preventible
Diseases," gave, the Author believes, the first expression, to
a popular audience, of the " Germ Theory " of Zymotic
Disease.

It is to the indomitable genius and philosophical sagacity
of Joseph Lister that, the contest, in regard to the application
of this theory to Surgery, is now virtually ended ; and, thereby,
one of the brightest, most benign, and even romantic chapters
has been added to the history of Medical Surgery.

The battle of the germ theory, however, in its relation to
the State control and prevention of infectious diseases, has
yet largely to be fought j and, to assist forward this great'
movement, in however small a degree, is the object in repub-
lishing this Lecture.

The second Lecture suflSciently explains its aim, , It is
intended to direct public attention to the great,, and, as the
Author thinks, preventible waste of life, incurred by a large
section of workmen among the industrial class, in the pursuit
of their employments. The appended tables exhibit the eff ects.

PREFACE.

in a great variety of occupations, in a light, for which, the mind
of the country may scarcely be prepared. They seem to call
for early legislative interference and prevention.

The Author takes the opportunity of claiming priority in
the discovery of micro-organisms, in living tissues. His delinea-
tion— of which a drawing is given — of the Rinderpest germ
was published in 1865, the next earliest being that of the
Spirillum of relapsing fever by Obermeier.

14 Charlotte Square,
Edi>'btjrgh, November 1883.

ERRATA

Lecture I., page 8. Fifth line from foot, for "four" read
"fourteen."

Lecture 11., page 29. Eleventh line from top, for " twelve
hundred " read " one hundred and twenty-five."

CONTENTS.

LECTURE I.

Preventible Disease— The Injury they Inflict -The Germ Theory— Plague
among Silkworms — Pasteur's Views confirmed — Different kinds of
Germs — Author's Discovery of Germs in 1865 — Cotton Wool as an
Air Filter — Distinctive Characters of Infectious Diseases — Increased
Bodily Temperature and Waste — Density of Population and Death
Rate — Law of Doisity to Death Rate — Overcrowding in Glasgow —
Carriers of Infection — Growth of Epidemics — SmaU-pox and Vaccina-
tion— Prevention of Epidemics — Compulsory Registration — Diffusion
of Sanitary Knowledge.

LECTURE 11.

Dust and Disease — Steel, Copper, and Lead Dust — Mineral Dust and
MortaUty — The Tobacco Workers, Weavers and Joiners — Millers,
Bakers, and Coal Miners — Immunity, from Consumption, of Coal
Miners — Wool-Sorters' Disease — Healthiness of Certain Occupations
— Mortality and Sedentary Employments with Defective Ventilation
— Effects of Arsenical Dust — Arsenical Poisoning in the Arts —
Germany and Poisonous Products — Dust and Consumption — Number
of Workmen Affected by their Occupations — Impoverishment,
Pauperism, and Hereditary Disease — Increase of Consumption —
Means of Prevention — Ventilation in Manufacturing Workshops —
Workmen and their Ameliorations — Need of Additional Legislation
— Attitude of Workmen to Questions of Public Health — State Educa-
tion— Historical Retrospect— Mortality of Industrial Workmen and
General Population compared — Pecuniary Losses to the State
through Disease and Premature Death of Workmen— Duty of the
Legislature.

27th Thousand,

LECTURE 1.

The title of this lecture is " Preventable Diseases and their
Causes," and I have chosen it to indicate as nearly as possible
the nature of the subject I have to speak of. Under this title
we include, for the present, only such as come under the head
of Zymotics — that group of diseases, viz. : which are more
directly affected by public measures of prevention, and by
the conditions which affect large communities. Many other
diseases which are, strictly speaking, preventable, such as
arise from noxious trades and unhealthy occupations, are not
here included, but will, I trust, at some future time, form the
subject of an interesting and useful lecture to you. A prevent-
able disease may be described as one which arises or spreads in
consequence of the wilful, careless, or ignorant violation of those
laws, the proper observance of which we know to be necessary to
insure the preservation of health, and avert the spread of disease.*
Those diseases — a very numerous group — which result from per-
sonal vices or from depraved habits of the community, are
beyond the immediate control of public measures.

The chief of the zymotic diseases are : — smallpox ; typhus
fever ; typhoid (or enteric fever) ; scarlet fever (or scarlatina) ;
dihptheria ; measles ; and Asiatic cholera. We will consider them

* Griuishaw.

THE INJURY THEY INFLICT.

from the following points of view : first, the injury they inflict ;
secondly, how they originate ; thirdly, their distinctive characters ;
fourthly, the conditions under which they spread ; and fifthly, the
means necessary for their control and prevention. " It seems
certain," writes Mr Simon, Medical Officer to the Privy
Council, "that the deaths which occur in this country are
fully a third more numerous than they would be if our exist-
ing knowledge of the chief causes of disease were reasonably
applied throughout the country ; that of deaths which, in this
sense, may be called preventable, the average yearly number
in England and Wales is about 120,000, and that of the
120,000 cases of preventable suffering which thus in every year
attain their final place in the death register, each unit represents
a larger or smaller group of other cases, in which preventable
disease not ending in death, though often of far-reaching ill
effects on life has been suffered. . . . Then there is the fact
that this terrible continuing tax on human life and welfare, falls
with immense over-proportion upon the most helpless classes ol
the community ; upon the poor ; the ignorant ; the subordinate j
the immature ; upon classes which, in great part through want of
knowledge, and in great part because of their dependent position,
cannot remonstrate for themselves against the miseries thus
brought upon them. And have, in this circumstance, the
strongest claim of all claims on a legislature which can justly
measure and can abate their sufferings."*

" Diseases of this class," says Dr Farr, the Eegistrar-General,
" distinguish one country from another, one year from another.
They have formed epochs in chronology; and, as Kiebuhr
has shown, have influenced not only the fates of cities such
as Athens and Florence, but of empii-es ; they decimate armies,
disable fleets; they take the lives of criminals that justice
has not condemned. They redouble the dangers of crowded
hospitals ; they infest the habitations of the poor, and strike the
artizan in his strength down from comfort into helpless poverty ;
they carry away the infant from the mother's breast, and the old
♦ iSth report of the Medical Officer of the Privy Council.

THE GERM THEORY.

man at the end of life ; but their direct eruptions are excessively
fatal to men in the prime and vigour of age." These Aveighty
words of the two greatest living authorities on this subject
ought to be Avell pondered.

Mr Simon reckons the deaths from these diseases at 120,000 in
England and Wales alone. If we add those in Scotland and
Ireland, from the same causes, the total mortality is over 150,000,
every one of which is a needless death. Does this not strike you
as a frightful waste of life 1 If we now compute that each one of
these deaths represents, at a moderate estimate, thirty instances in
which there is loss of health short of death, the aggregate of need-
less death aud suffering becomes perfectly astounding, and affords
a sufficiently cogent reason why zymotic diseases are specially
singled out to be dealt with by stringent enactments having for
their object their prevention, and ultimately total extinction.

THE GERM THEORY OF INFECTIOUS DISEASES.

How THEY Originate. — The term Zymotic is applied by those
who believe that in these disorders there takes place a process
which bears a strikins; resemblance to that of fermentation.
This resemblance was first pointed out by Leibig. Thus, when
yeast is added to a solution of sugar, the yeast cells rapidly mul-
tiply by feeding on it — alcohol and carbonic acid being given
off during the process. Yeast, I should tell you, is a rudi-
mentary plant composed of cells, which, when placed in a
suitable medium, actively multiply, living at the expense of
the medium in which they exist, and ultimately changing its
character. (See Diagram.) This is fermentation, as it occurs
outside of living bodies, and is the starting-point of the idea
that germs of different kinds — animal and vegetable — are the
active agents in the production of zymotic diseases. That
these germs do exist abundantly in the air, and elsewhere, has
been proved by the experiments of many observers, and especially
by Pasteur, a French physiologist. [Here describe and show
Pasteur's experiments with air and liquids in sealed flasks.]

PLAGUE AMONG SILK WORMS.

Pasteur found by experiment that certain changes which some-
times take place in beers and wines, during the course of pre-
paration for use, and which he calls " diseases," are owing to the
presence of vegetable germs, every particular change being due
to a different kind of germ. Another investigation, which he
undertook at the earnest entreaties of his friend and preceptor
Dumas, the celebrated chemist, resulted in a discovery which
throws interesting light on the same subject, by showing how
animal germs may be the cause of a disease among animals of a
very destructive and infectious kind. France, a few years ago,
was threatened with a great calamity. For fifteen years a plague
had raged among its silkworms. In 1852 the silk culture of
France yielded a revenue of 160,000,000 of francs; ten years
later it had fallen to 4,000,000. Pasteur found that the bodies of
the silkworms which had the disease were infected by minute cor-
puscles, which, taking possession of the intestinal canal, spread
thence throughout the body. They filled the silk cavities, the
stricken insect often going through the motions of spinning with-
out any material to answer to the act. The organs, instead of
being filled with the viscous liquid of the sUk, were packed to dis-
tention by these corpuscles. On this feature of the plague Pasteur
fixed his whole attention, and brought the inquiry to a triiunphant
issue! By inoculating the healthy worms with the corpusculous
matter, he found the disease to be highly infectious. He further
showed how the silkworms infected one another by inflicting
wounds upon each other by means of their claws. He washed
the claws, and found the infecting corpuscles in the water. He
next spread the infection by simply bringing the healthy and
diseased into contact. The diseased worms sullied the leaves of
the mulberry tree among which they spin, and by their dejections
spread infection in both ways.*

These observations exemplify in the most striking manner
what actuaUy takes place in some of our own zymotic diseases.

Whatever be the difference of opinion as to the precise nature
• (Tyndall— " Dust and Disease.")

PASTEUR'S VIEWS CONFIRJIED.

■J

*f the infecting elements in these diseases, whether they be the
rudimentary forms of animal or vegetable life, or merely particles
of our own bodies which have acquired a poisonous property
which does not naturally belong to them, most are now agreed, I
think, that such particles have a veritable existence.

With the limited time at my disposal, I can but give you the
briefest account of the proofs that have recently been accumulating
in support of Pasteur's views, besides those of many other obser-
vers,* that thai something by means of which infecting diseases
pass from one to another, has a real existence, is an organised
solid, however minute, which is the absolutely indispensable
agent in the transmissibility of these diseases. These opinions
mark a great advance in the medical views of the past few years.
The phantom of what used to be called an " epidemic constitution
of the atmosphere " has ceased to haunt us, whUe sanitary and
medical science are more and more mustering their resources for
the utter destruction of those invisible potentialities which are
everywhere about us, " both when we sleep and when we wake."
Let me illustrate what I have said by means of these diagrams.
You see those particles ; they are so minute as to require the aid
of a powerfully magnifying lens to bring them into view. They
are obtained by filtration from vaccine lymph, which appears to
our unassisted eye to be a clear fluid. If the lymph without the
particles be used to vaccinate, it entirely fails ; but if the particles
be used without the fluid, it perfectly succeeds. You will better
understand what I mean when I tell you that a person undergoing
vaccination, is passing through a mild or modified form of small-
pox. These particles may be therefore regarded as the virtual
agents in the production of smaU-pox. Similar particles per-
fectly alike in outward form exist in the lymph of Glanders or
Farcy, a most virulent disease which attacks horses, but is com-
municable to man. A horse inoculated with the fluid, without the
particles, would escape, but not if it contained the particles.
In this other diagram you have a view of infecting germs deri\'ed
• Obermeyer, Klebs, Chaveau, Burdon Sanderson, Lister, Greenfield-

DIFFERENT KINDS OF GERMS.

fi-om the vegetable kingdom (Bacillus anthracis), namely, the rod-
like fungus of anthrax, a fatal disease, chiefly attacking animals
such as the horse and ox, and sometimes man. These infecting
particles resemble, as you see, minute rods. They grow into
fibres, then fructify, each one producing a number of spores, which
are the oval bodies seen in the diagram. In this disease, these
germs infest the tissues and blood of the infected animal or per-
son, and live, grow, and multiply at the expense of the tissues
and blood. If now the blood containing these rods and spores
be filtered, it becomes harmless, that is, it will not infect another
animal. But, on the contrary, these bodies will cause the disease
in its most virulent form.

This diagram shows a drawing of a section of skin in erysipelas,
an infectious disease of a rapidly spreading nature, characterised
by great inflammatory swelling and redness (hence named St
Anthony's fire). The dotted portions indicate the lymph vessels
and spaces, the dots representing minute vegetable spores
(micrococci) crowding the spaces. There is no longer any doubt
that diphtheria is a disease essentially due to the presence of
similar parasitic organisms.

This other diagram furnishes an example of another Icind. It
exhibits the spirilla of relapsing fever,* sometimes called famine
fever, from its occurrence during periods of scarcity. You readily
distinguish the organism existing among the blood-corpuscles by
its spiral or corkscrew appearance. This fever relapses for a
week, then suddenly re-appears for a week, and so on, hence its
name. The spirilla is found in the blood when the fever comes
on, and disappears when it goes ofi", and finally disappears, when
the sufi'erer recovers — thus proving its connection with the disease.

Another discovery has lately been made by I'rofessor Klebs
throwing much interesting light on the causation of marsh or
malarial fever. He found a species of vegetable organism exist-
ing in the air of the Pontine marshes, which, when injected under
the skin, produced that fever. Further proof of the connection

* Obermeyer.

author's discovery of germs in 18G5.

of these organisms with malarial fever is found in the fact that
they are present in the organs, and in the blood of persons who
die of marsh fever.

I found rod-like germs abundantly present in the blood of
animals attacked with cattle plague, one of the most intensely
infectious diseases that ever visited this country. They are de-
lineated in my reports on the subject to the Authorities. So far
as I am aware, it was the first time that they were shown to exist
in the blood of hving animals.* A few facts will better enable
you to comprehend the enormous fertility of germs and spores.

Among the larger animal germs, which are visible to the naked
eye, and may therefore be counted, the late Mr Buckland found
no fewer than seven millions of eggs in a single cod-fish. The
Ascaris, an intestinal worm infesting man and other animals, pro-
duces about sixty-four millions of eggs ; and in the vegetable
kingdom some single plants yield over seventy-four millions of
seeds in a season. Numerically great as these figures are, they are
dwarfed by the greater productiveness of the spores of some fungus
plants. They are inconceivably minute — two hundred millions,
side by side, would not cover a square inch — yet they possess an
inherent vitality, which, under favourable circumstances, -will burst
into life, reproducing the parent plant from which they sprung.
Again, we are told that spores, equal in number to the entire
inhabitants of the globe, placed side by side, may easily rest on a
space four inches square ; and that one million would find ample
accommodation on the head of a pin !

Professor Tyndall was the first, I think, to make these facts,
viz., the presence of particles in the air, palpable to our senses
by an experiment which you can all make for yourselves. He
let a sunbeam into a darkened room, through a chink or hole
in the shutter. The bright ray revealed the floating dust — for
it is a fact that without dust there would be no visible ray.
It is the particles of dust that intercept and scatter the light
and make it visible to us. A smiilar efi"ect is produced when

* September, 18G5.

COTTON WOOL AS AN AIR FILTER.

a bright ray, for example, from the electric light, or lime
light, is thrown across a darkened room. "When the flame of a
s]!)irit-lamp is then placed under this ray it gives the appearance of
smoke passing through it, but there is no smoke from the spirit-
lamp, and the black space is produced by the heat of the lamp burn-
ing the particles floating in the luminous beam, and for the time
being rendering that part void, or empty of particles. The black spot
thus produced is said in scientific phrase to be " optically empty."

The experiment may be turned to practical and really useful
account, by showing us that these particles may be prevented from
entering the lungs. Thus, a handful of cotton is placed against
the mouth and nostrils, and a full breath inhaled through it, which
is easily done. The cotton is now removed, and the air in the
lungs made to pass through a glass tube into the luminous ray,
when a dark smoke-like space is seen, as in the previous experi-
ment with the spirit-lamp. This shows that the air is filtered of
its particles by passing through the cotton.

DISTINCTIVE CHAEACTERS OF INFECTIOUS DISEASES.

Accepting, as we do, the theory that each case of infectious
disease originates in the reception of a distinctly specific, pre-
existing poison, and that it in turn becomes self-propagat-
ing, we now go on to speak a little in detail of each of these
zymotics. There are some features which are common to the
whole group. They all, for example, begin with a period of whal
is called "dormancy" or "latency" or "incubation," during which
the poison is actively developing. But the duration of this
period differs in each case. That of smallpox is twelve days ;
typhus fever, eight to fourteen days ; typhoid fever, fourteen to
twenty-one days ; scarlet fever, three to six days ; measles, about
four days. These diff'erences in the length of the incubation
period being probably due in each case to the amount and
strength of the poison received. At the termination of this
period, the sickness is said to begin, although its distinctive
character may not appear for some days longer. These fevers

DISTINCTIVE CHARACTERS OF INFECTIOUS DISEASES.

are all ushered in by a marked, and sometimes sudden, elevation
of bodily temperature, which, with variations, continues during
the course of the illness. It is because of this increased tempera-
ture that they are called fevers. Characteristic eruptions now
appear. Scarlatina on the second, measles on the fourth, and
smallpox on the third day, and so on. Now begins the infecting
period, which increases Avith the activity of the disease.

Smallpox. — The patient is now charging the air, and everything
about him, with a most subtle and deadly virus, derived chiefly
from the skin and mucous membranes, but not restricted to them.
There is no contagion so strong and sure, or that operates at so
great a distance, passing from house to house, from street to
street, making sanitary precautions difficult. I regret to add that
cases of this disease, imported from London, are already here.

Typhus fever once contracted is highly infectious, and essen-
tially a disease of over-crowding and foul air from deficient
ventilation, associated with squalor and want, and a deteriorated
constitution from whatever cause. It chiefly infects by exhala-
tions from the skin and lungs. The patient's bedding and clothes
become saturated, and the poison clings so persistently to the
walls, and to everything in the room, as to make the destruction
of the latter in many cases necessary.

Typhoid fever differs from the preceding in its being but
slightly, if at all, infectious through the air. Here the seat of the
attack is the intestinal canal chiefly, and the poison is mainly
eliminated by that channel. It is accordingly the intestinal
discharges, and clothes or bedding tainted with them, that have
to be mainly looked to, and every precaution taken by disinfec-
tion and removal, to prevent their access to water sources, such as^
wells, or into house drains; where, by decomposing, they infect by
their effl uvia. These discharges acquire their maximum infective
power when decomposing.

1 0 INCREASED BODILY TEMPERATURE AND WASTE.

Asiatic Cholera.— We are fortunate in this country in beiny
rarely visited by this Oriental epidemic. The precautions are the
same as in typhoid fever— the source of danger being alike in
both cases. It is astonishing how small a quantity of intestinal
discharge in these disorders, especially in cholera, will taint the
water supply over a large area, which may mean death to
thousands. Dr Farr estimates that in cholera, if these fluid
discharges contain infecting particles in the same proportion as
blood corpuscles exist in healthy blood, forty-two millions of them
would be set adrift during the progress of a single case.

Scarlet Fever. — There is perhaps not any other illness that
you are all more painfully familiar with than this fever. It is a
household experience, a troublesome one, which is regarded very
much as inevitable.

Although no age is exempt, it is essentially a children's illness
— attacking mostly between the ages of three and four, and the
risk lessens after the fifth year. Its poison is most active and
penetrating, and retains the power of infecting for indefinitely
lengthened periods. As nearly all the fluids and tissues partici-
pate in the attack, they may all infect, — the skin by casting its
outer surface, the internal membranes by a like process, tainting
the secretions. Isolation, that is separation, is a necessary part
in the treatment of this fever. The worst cases are associated
with malignant sore-throat, which so far brings it into relation
with another very infectious malady, viz.. Diphtheria, the seat
of which is chiefly the throat and upper air passages, and the in-
fecting channels, the breath and expectoration. I have said that
these disorders are all marked by increased bodily heat. This
is, however, but one of the many symptoms which signalizes their
course. In most the heart's beats are doubled ; the blood courses
along the vessels with redoubled velocity ; the respirations are
doubled. The whole vital machinery is working under its highest
possible pressure. Bodily waste is more than doubled. In or-
dinary health our bodily substance breaks up, and is parted with

DENSITY OF POPULATION AND DEATH RATE,

at an expenditure equal to several pounds' weight per day ; but
during the febrile state health limits are vastly exceeded.

I leave you to draw your own conclusions as to the consequences
which must follow to others, when this enormous amount of
infective material is daily set adrift — for we must remember that
our waste and effete materials, under these conditions, become
charged with the virus of the disease !

I wish now to say a few words on what has been fittingly
named —

THE BREEDING PLACES OF INPECTIOUS DISEASES.

For this purpose I select some of those localities from which
these diseases ai-e never altogether absent, and from which they
usually go forth upon the rest of the community. Examine with
me for a little these diagrams : — Of these six columns, the shortest
represents the healthiest district, the tallest the unhealthiest,
shelving the extreme of six districts existing in different parts of
a neighbouring city. The upper portion of each column represents
the number of deaths from the infectious diseases which occur
in each of these districts ; the middle portion, the number of
deaths resulting from pulmonary diseases, mostly consumptive ;
the lower portion, the deaths from what is called " unclassified "
diseases. Now, notice that the rate of deaths steadily increases;
thus, in the district represented by the shortest column, the in-
habitants are aggregated together in the proportion of thirty-five
persons to every acre of it, and its death-rate is nineteen persons
per thousand annually. In the next they are aggregated together
in the proportion of four hundred and twenty-six persons to every
acre; and its death-rate is thirty-five persons per thousand
annually. In the third, their aggregation is in the proportion of
four hundred and fifty per acre, with a deaLli-rate of thirty-eight
per thousand. The fourth, the proportion is three hundred and
tifty per acre, and the death-rate forty-one per thousand. The
fifth is, three hundred and fifteen per acre, and a death-rate of

LAW OF DENSITY TO DEATH RATE.

forty -three per thousand; and, sixthly, in the highest colunm, ther
are aggregated together in the proportion of five hundred and
eighteen, with the death-rate of forty-five per thousand. The
fourth and fifth are only apparent exceptions to the rule of an
increasing death-rate with an increasing density of popidation.
The inhabitants of these districts, although fewer, are more
densely huddled together.

Look now, for a moment, at the composition of each of these
columns, and you will observe that the death-rate from infectious
diseases, not only steadily increases with the density of its popu-
lation, but also that from pulmonary and " unclassified " diseases.
These groups are represented in different colours, and will assist
you to form a juster conception of the dangers resulting from
over-crowding.

The credit of working out, and applying this important law of
death-rate to density, belongs to Dr Farr.

Taking the five hundred and ninety-three registration districts
into which England and Wales (not including London) are divided,
he arranges them into so many groups according to their densities,
beginning with the most thinly populated rural district, with only
a hundred and sixty persons to the square mile, and ending with
the most densely packed town districts, as Glasgow and Liver-
pool, with over sixty thousand on each square mile. Let us now,
with the assistance of these other diagrams, note the results.

In the district with 166 on each square mile there is a death-rate of 17 p. lOOO
I, i» 3/9 ,f J, f,

>> 1) 1718 ,1 II II

II 11 4499 II II II

,1 II 12,357 (Manchester) „ ,,

,, I, 66,000 (Liverpool) „

Glasgow, with a density of population nearly similar to that of
Liverpool, has a much lower death-rate, thanks to the en-
lightened exertions of its able health officer.

How comes it then, that persons living in thinly-peopled rural
districts (165 to the square mile\ die annually in the proportion

22
25
28
38
39

uVERCROWDING IN GLASGOW.

of 17 per 1000, while those of Liverpool perish in the proportion
of 39 per 1000? "What is the cause of this greatly increased
mortality ? I cannot answer this question better than by quoting
the words of the accomplished Medical Officer of Glasgow, Dr
Russell, to whom I have just referred: Density," he remarks,
" means, in relation to Glasgow, that three-fourths of those human
beings live in houses of one and two apartments, that those houses
are built in tail tenements, so arranged on the earth's surface as
to exclude the sunlight and impede the circulation of the air, more
especially that a large proportion of those tenements are arranged
in hollow squares. ... It means that inside those boxes there are
ash-pits, . . . that planted among those ash-pits we have hundreds
of ' back lands,' along with stables, byres, bake-houses, work-shops,
washing-houses, and other smoke and efBuvia producing erections,
that the stairs are often close and badly ventilated, that they are
at best vertical streets, with lanes and alleys branching off at the
several landings, ... It means that hundreds of factory chimneys
and thousands of domestic vents, maintain over aU this devoted
area a dense canopy of smoke, which in summer cuts off a large
proportion of the sun's rays, an extra supply of whose decompos-
ing energy ought if possible to be secured to aid in the destruction
of the organic particles which are so rife in the air of cities,
and which, in the winter, descend upon us with the watery
vapour of our fogs. . . . Our rivers and streams are loaded witli
the foulest refuse, that the subsoil is traversed by a net-work of
sewers, drains, and gas-pipes, and is therefore so impure that the
ground air is loaded with noxious effluvia, and the ground water
is so foul that to drink it would be poisonous, if, indeed, it could
be done.

" Finally, it means that for grassy fields we have stony streets,
and in place of trees we have lamp-posts, and altogether we are
as far shut out from the ministry of nature as the necessities of
the case, combined with the aggravations of human ignorance,
perversity, and wilful self-aggrandisement, can place us."

CARRIERS OF INFECTION.

Wc ha.ve now to speak of

THE CONDITIONS UNDER WHICH INFECTIOUS
DISEASES SPREAD.

The Carriers of the Infection. — We have seen how readily
infecting germs may be dispersed, wafted by the air, carried by
water, tainting our clothes, oiir money, and the commodities given
in exchange for it. The mutual dependence of class upon class,
and their unavoidable concourse, the relationships of life, as
well as its vicissitudes and necessities, all tend to bring people to-
gether— in short, the entire machinery of society such as we find
it, is peculiarly adapted to spread infectious diseases.

There can be little doubt that the spreading of these diseases,
in the majority of cases, is brought about by the healthy coming
into contact with the sick or convalescent. Children after an
attack, are allowed to go back to school too soon, and the result is
renewed outbreaks of scarlatina, measles, and whooping-cough.
The laundress disseminates the poison of scarlatina and smallpox
amongst her employers ; nurses carry it from sick-beds to their
own homes ; the tailor and dressmaker often ply their needles
close to fevcr-strickeii patients. One doctor writes that he has
seen the garments, which were thus being made at theii- homes,
used to eke out the scanty bed-covering of a fever patient;
another, that he received a patient into hospital with smallpox
pustules on him, who had on the previous day been occupied in
dressing ladies' hair. I myself lately entered a house of one
room with eight occupants, five of whom were laid down with
scarlatina. In the midst of this, the father, an enfeebled man,
was trying to earn a little money by working at a couch which
ere many days would too surely carry disease into some house-
hold. These persons have our deepest sympathy, and if we speak
of their hard necessities, it is in the hope, and with the earnest
wish that we may be able to mitigate, or remove them.

Let us vary the illustration by another example. The milk-
cans, we shall suppose, at a farm-dairy have been unwittingly

GROWTH OF EPIDEMICS.

washed with water coirtammated with sewage ; or, perhaps, a little
of that element has been added to improve its quality ! — then fol-
lows what is significantly called " the trail of the milk-man "—a
trail marked by fever cases in perhaps every house to which the
milk has been distributed.

Or there is a fever at one of our town dairies, in the back-room
of the shop, for example, and the attendant on the sick also
attends to the customers, who carry the milk to their homes, and
with it the germs of future disease. This diagram will assist you
to realise more vividly what I have just said. It represents a
farm-house in which typhoid fever has arisen, by the milk becom-
ing tainted in the way I have spoken of. This dot marks the
first case which arose in consequence.

Observe how the disease spreads from this starting-point. This
other dot shows the second case, which arose in nineteen days
from the first, and this, the third, in twenty-six days from the first
— all in the same house; but in fourteen days from the first case,
a group of three cases occurred in a family, supplied with milk
from this farm, and within eight weeks from the first case, a hun-
dred and sixty-six persons were laid down with the fever.

Look now at this diagram, illustrating the growth of an epi-
demic of scarlet fever, from a single case.

It is a moderate estimate of the rate of progression of this fever,
to say that each case produces two others. Follow these dots
from the starting case, and in seven weeks from its commence-
ment, you will see that the one case has multiplied into two hun-
dred and fifty-six. Once more, study with me this diagram
marked cholera. I have said that this disease is propagated by
water, fouled by choleraic discharges. Estimating that each case
produces five others, a ratio which may be taken as considerably
under its usual rate of progression, there would arise six hundred
and twenty-five cases within eight days. Several instances
of this actually occurred during the cholera epidemic of 1866.

The presence of an epidemic of small-pox in London, and
the certainty of its early advent amongst ourselves, lead me to

SMALL-POX AND VACCINATION.

invite your very special attention to tins other series of diagrams,
which exhibit in the most convincing and instructive manner,
the influence of vaccination in preventing and modifying that
disease under different conditions and periods of life. They
show the results, based upon a most painstaking and successful
investigation, of a thousand cases of small-pox, treated in hos-
pital durmg 1871, by Dr J. B. Russell. The diagram, as you
observe, is divided into large squares, each being subdivided
into one hundred smaller squares, so that each large square
represents one hundred cases of small-pox. The colouring
again, whether black, red, or white, tells you the degree of
severity with which each case was affected. Those portions of
the squares in while, show how many were attacked with the
mildest, or seldom fatal form of the disease (with rare or sparse
eruption). Those in red indicate intermediate, or frequently fatal
conditions of the disease (copious eruption) ; while the black marks
the dangerous, or very fatal type of the malady (confluent erup-
tion).

The upper row of squares, from left to right, shows the efi'ectiii
of vaccination — between the periods of infancy and adult life —
when well done ; the corresponding middle row, its efi'ects when
hadly done ; and the lowest row, when not done at all.

By glancing at the diagrams in this order, you will at once
observe, that the weU- vaccinated, as they grow older, take the
disease in a slight/ljT severer form ; the badly vaccinated in a
much more severe form ; and those who have not been vaccinated
at all, are throughout their whole lives — from infancy upwards —
subjected to the very worst and most fatal form of the disease.
In other words, you will not fail to draw the inevitable conclu-
sion, "that the influence of vaccination, well and thoroughly
done, extends, with but little loss of protecting power, tlirough-
out life ; while, if badly or imperfectly done, it is nevi i so efii-
cient a protective power, gradually loses what protecting power it
had possessed, and finally leaves the badly-vaccinated individual

PREVENTION OF EPIDEMICS,

only a little less susceptible than he who has never been vaccin-
ated at all." *

Each of these infectious fevers grows and spreads by conditions
peculiar to itself, which depend, to a considerable exf ^nt, on the
length of its incubation period.

The two first of these diagrams show sufficiently well the
manner in which the recent epidemics in Edinburgh of typhus,
typhoid, and scarlet fevers began, and spread ; as also nearly the
numbers affected, and the duration of the epidemics.

AVe have now to speak of

THE MEANS NECESSARY FOR THE CONTROL AND
PREVENTION OF INFECTIOUS DISEASES.

The instructions intended for your guidance in emergencies
which I have drawn up, based on my lecture,! are, I understand,
already in your hands ; and I am thus so far relieved from many
details, which it would otherwise have been desirable for me to
touch upon. I will ask you then to hold that part of my lecture
as read ; and I will now proceed in a few brief sentences to
enumerate those measures for the effectual control and preven-
tion of epidemic disease which I consider to be necessary.

Firstly, We must aim at the promotion of cleanliness of every
description, by the employment of those legal powers contained
in public health enactments, which are amply suflBcient for the
purpose if carried out.

Secondly, At placing all building operations — such as the con-
struction of houses, selection of healthy sites, house and general
drainage — under strict sanitary inspection and supervision.

Thirdly, At preventing over-crowding, alike in dwellings or in
districts. This measure comprehends the constant inspection of
houses, the width of streets, the height of houses, the removal
of old and insanitary dwellings, the promotion of open spaces,

* Lectures on the "Prevention and Control of Infectious Diseases," by
Dr J. B. Russell,
t See Appendix.

C05IPULS0RY REGISTRATION.

and the opening up of thoroughfares through dense and insani-
tary neighbourhoods. Thanks to the efforts of our late Lord
Provost Chambers, a good beginning has been made in this direc-
tion in this city.

Fourthly, It will be found utterly impossible to prevent infec-
tious diseases without a more stringent act in regard to their
registration. Nothing short of the compulsory registration of these
diseases will effect this end. To prevent their spread it is essential
that the authorities should be early apprised of the existence of
every case.

Fifthly, Following from this the authorities should be entrusted
with the discretionary power of compulsory removal. This power
will never be abused ; and,

Sixthly, — Such powers imply, and, indeed, necessitate, on their
part, the providing of ample accommodation for the reception of
infectious diseases, as will suffice to meet the emergencies of
epidemics ; for the reception of actual cases, convalescent cases,
suspected cases ; and further, for the reception of patients who
may voluntarily desire to be treated in hospital. There are many
6uch, who, though comfortably circumstanced in their own homes,
«vould gladly avail themselves of this provision. It may interest
you to know that the late Sir James Simpson expressed his deter-
mination to be treated in hospital in the event of his suffering
from an infectious illness. All such arrangements would require
to be carried out in a liberal interpretation of the acts. For
example, the greatest difficulty is experienced in the removal of
children, from the unwillingness — a natural one — of mothers to
be parted from them during their illness.

Mothers, under certain restrictions, should be admitted to the
hospital to nurse their own children.

It is proposed to acquire the ground and buildings of the old
Royal Infirmary as a hospital of this kind, under the entire con-
trol of the civic authorities. This is a step in the right direction.

We enjoy the services of an able and energetic medical officer,
whose heart is in his work — but. without such powers and provi-

DIFFUSION OF SANITARY KNOWLEDGE. 1&

sioHS as I have indicated, the best efforts of the authorities and
of their medical officer will fail of their object.

I have only, in conclusion, to add that it is most desirable to
have our people thoroughly informed in regard to sanitary
matters, in order that they may heartily and intelligently assist
in promoting what is really necessary for their own and their
neighbours' good.

To further this desirable movement has been, I know, the
cherished object of the promoter of these " Health Lectures for the
People."

Al the close of the lecture Dr Smart showed Professor Tyndall's
experiments by means of the lime-light.

APPENDIX.

ON PREVENTABLE DISEASES AND THEIE CAUSES.

GENERAL PRECAUTIONS.

1. The following preventable diseases (called also zymotic) are all infec-
tious. The chief of these are : — Scarlet fever, typhoid (or enteric fever),
typhus fever, smallpox, measles, diphtheria, whooping-cough, and
Asiatic cholera.

2. When any of these illnesses (except whooping-cough) enters a
household, the patient should be, if possible, at once separated from the
rest of the inmates (especially from the bread-winners) ; the children
who ai-e in health kept from school, and as much as possible from
mixing with other children.

3. The sick-room to be divested as much as possible of every article
of needless furniture, especially of woollen fabrics, such as carpets,
curtains, cushions, &c. ; to be well ventilated by means of a fire
constantly burning, and the strictest cleanliness observed.

4. A large vessel (a tub) to be kept in the room, containing a couple
of gallons of water mixed with carbolic acid, in the proportion of one
wine-glassful of the liquid acid to each gaUon of water. Into this, every
article of clothing, bed-clothes, &c., removed from the patient, should
be immediately plunged, and kept there for twelve hours, and then
washed apart.

5. A basin containing water, having two tablespoonfuls of Condy's
Fluid added to it, to be always in readiness for cleansing the attend-
ant's hands, or sponging the patient when necessaiy. This solution
should be renewed when it is seen to lose its briglit purple colour.

6. A sheet dipped in the cai-bolic solution named, should be hung
over the door of the sick-room, reaching to the ground, and kept con-
stantly damp by means of sprinkling or a sponge. Only the attendant
to enter the sick-room.

7. The dress of the attendant should be of cotton, or of some washable
material, with smooth surface.

8. Food that has been in the sick-room, on no account to be used by
the other inmates. It is desirable for many reasons, that tlie attendant
do not take her meals in the sick-room.

9. Dishes, and vessels of every kind used about the patient, ought to
be thoroughly cleansed before being used by others.

APPENDIX.

10. All discharges from the sick to be received into vessels containing
disinfectants (Calvert's or Macdougall's Carbolic Powder), and, if con-
venient, deposited in the ground to the depth of about two feet. If
disposed of by w.-c, it should afterwards be freely flushed with the
carbolic solution.

SrECIAL PRECAUTIONS.

SCAELET FEVER.

11. To prevent infection by the particles which peel off from the
skin, the patient should be anointed once a-day with carbolic oil, made
with one part of carbolic acid, to fifty of oUve oil. The efilorescence
(or peehng off) is first seen on the skin of neck and arms, and begins
sometimes as early as the fourth day. The anointing should be com-
plete, including the head, the oil being freely applied to the roots of
the hah". This should be continued for six weeks, a warm bath being
given weekly during that time. After this period (six weeks), the
patient may mix with the other members of the family j but children
should not retm-n to school for two weeks longer.

MEASLES.

12. The same rules as above to be observed, with the addition that
the discharges from the mouth and nostrils should be received on
cloths which may be destroyed by burning.

TYPHOID FEVER.

13. The poison by which this fever spreads is chiefly contained in
discharges from the bowels. These may infect the air of the sick-room,
the bed, and body-Unen of the patient, and the w.-c. and drains con-
nected with it. If thence they escape to the soil by soaking into wells, they
poison the drinking-water. This is a common and dangerous way by
which this fever spreads. To prevent such consequences, the discharges
should be disinfected on their escape from the body as previously
directed. This is the cAi'e/ precaution to be attended to, and if effectually
done, removes almost all the risk of infection.

TYPHUS FEVER.

14. This is a much more " catching " fever than the preceding, and is
caused by over-crowding and deficient ventilation. It is apt to attack
those who are much exposed to it for the first time. It is therefore better
to have a nurse who is protected by a previous attack. The poison is
throvm off by the skin and lungs and readily infects clothing, furniture,
etc. ; so that the chief precautions are those of ventilation and disinfec-
tion.

APPENDIX.

SMALLPOX.

15. The perfect protection from this disease is efficient vaccination.
This is known by a good large mark, or scar. Re-vaccinjition after the
fourteenth year is advisable. An unvaccinated case of smallpox in
Scotland is so rare, that precautions in regard to it are needless.
Should such a case occur, tlie precautions already named should be most
strictly adhered to, as it infects at a greater distance than any other in-
fections disease.

DIPHTHERIA.

16. Diphtheria poisons by means of the breath and expectoration ; and
the utmost precaution to avoid contact with these on the part of those
about the patient is absolutely necessary. The expectoration should
be received into a vessel containing Candy's Fluid, or on cloths that
may be at once burnt ; and the throat frequently gargled with a solu-
tion of the same, of the strength of a small teaspoouful to a quart of
water. A mother should on no accoxmt kiss her children during this,
nor, indeed, any of the other infectious illnesses.

WHOOPING-COUGH.

17. Whooping-cough is a disease to which children are more especially
susceptible, and most fatal to children under two years of age. It is so
nxtremely fatal to infants, that every effort should" be made to keep them
out of the range of the infection by separation. The poison comes
chiefly from the mucous secretions of the lungs and air passages, and
is readily imparted to the clothes of those who nurse the patient
These secretions ai-e infectious from the beginning of the illness.

ASIATIC CHOLERA.

18. Tliis only occasionally visits this country. As in typhoid fever,
it spreads by means of the bowel discharges ; and the same precautions
are necessary.

GENERAL STATEMENTS.

19. In any of these infectious diseases, where there is not sufficient
accommodation for fully carrying out these precautions, it is urgently
recommended that the patient be removed at once to the Hospital
appointed for the reception of such cases. It need hardly be added,
that no time should be lost in obtaining medical advice when any of
these diseases appear.

20 We abstain from giving directions as to the disinfection of a
house either after death or recovery, as the authorities gratuitously and
efficiently do this when applied to ; besides making ample compensation
tor any articles of furnitm-e, &c., they consider it necessary to destroy.

Microscopical Examination of Dust suspended in the Air*

ISrERNAL (OR IFAKD) AIK.
I. Epithelitivi from the Mouth, 2. Ditto from the Skin. 3. Mitiernl
Dust. 4. Flax Fibre. 5. Striped Muscular Fibre. 6. Animal Cells.
"].. Cotton Fibre. 8. Unstriped Muscular Fibre with Fat Globule adherent.
9. Fungi and .Spores. 10. Woollen Fibre.

EXTERXAL AIR.
I. Epithdium Cell from the Mouth. 2. Ditto Scales fvm Shin. 3. Linen
Fibre. 4. Mineral Dust. 5. Cotton Fibre. 6. I/air. 7. IVoody Fibrous
Tissue. S. IVooUen Fibre.
^ \-EGETABLE DUST.

I, /./«£■« /V^r^. 2. Hemp. 3. Cotton. 4. /f^W.

I. Flinty Granules ivith sharp edges. 2. The same with edges rounded off.

^ Ttic examinations 0/ the Ward ami External Air ivct e, at tlie auilior's reqvest,
kindly made by Dr Wood, House I'liysician, Old Royal Infiminri' ; to wtiirm hr is also
indebted /or the accompanying .Sketch.

LECTURE II.

It would, doubtless, have added to the interest of the subject,
had the limits of my topic allowed me to include, however
briefly, some notice of those occupations which we are accus-
tomed to speak of as the "professions." It could not fail to
interest, as well as instruct you, to know why our Divines, by
which I mean the clergy generally, pre-eminent by their learning,
eloquence, piety, active benevolence and public spirit, should add
the further distinction of being the longest lived; or why
the legal profession, in its different branches, certainly, not
less eminent in this metropolis, by their great talents,
learning, literary tastes, solidity of judgment, forensic skill,
and unique business capacity, should rank only second in the
enviable possession of longevity. Or again, curiosity, if no
other motive, might prompt in you the wish to know why the
average life of the medical man should fall so considerably short
of that of the preceding. But these professions and other
interesting occupations do not come under the designation of
"unhealthy," to which category I am restricted. But let me
say, that, apart from them, I find that my theme is sufficiently —
if, indeed, not too ample. And there is this further drawback,
that the subject has not hitherto received, at least in this
country, the attention to which its importance entitles it.

We are, accordingly, almost without any reliable statistical
data or facts.* I am therefore obliged to seek for them else-

* Thackrah's work, published in 1833, is not based on statistical data.

DUST A CAUSE OF DISEASE.

where, and to construct and arrange the evidence upon which I
wish all my statements to rest.* Should I, in doing so, tax your
time, or tire you with calculations, I must bespeak your indul-
gence ; but it shall be my endeavour to avoid this.

Nearly all trades and manufacturing processes are attended
by the evolution of dust, or of volatile particles, more or less
considerable and more or less hurtful.

Persons habitually breathing a dust-laden atmosphere of this
kind, acquire a liability to diseases of various sorts ; but as the
inhaled dust is necessarily, in every instance, brought into contact
with the lungs, it is accordingly the pulmonary organs that chiefly
suffer in the end. I propose, in this lecture, to direct your atten-
tion, as fully as time will permit, to the injurious effects of certain
occupations upon the health of those employed in them ; and, to
enable me the more succinctly to do this, I shall state what I have
to say under the following heads : — Firstly, the effects of metallic
dust ; secondly, the effects of mineral dust ; thirdly, the effects
of vegetable dust; fourthly, the effects of animal dust; fifthly^
the effects of certain gases and volatile emanations ; sixthly, the
effects of constrained bodily position, conjoined Math defective
ventilation ; seventhly, the effects of dust from poisonous metals ;
and eighthly, certain considerations as to the prevention of these
effects.

Metallic dust is of different kinds ; and we shall speak first of that
which is emitted during the processes of iron and steel working.
You have all, doubtless, curiously watched the operations of the
street scissor-grinder as he plies his vocation. Each time the blade
touches the swiftly revolving M'heel, the grinder's head, as he bends
over it, is enveloped in dust and sparks. Now, this peripatetic
steel-grinder encounters no risk from his occupation only because
it is carried on out of doors ; but were you to enter one of the
busy workshops of Sheffield, and, for a time, amid the turmoil
of machinery, attempt to breathe its stifling atmosphere, charged
with minutely pulverised dust, emitted by hundreds of wheels,
you would have a practical experience of the cause why few, if
even one, of all the workers there will ever reach their fortieth year.

* Vide appended Tables.

STEEL, COPPER, AND LEAD.

Take the following examples. The average duration of life
among the dry-grinders of forks is twenty-nine years ; of razor-
grinders, thirty-one years ; edge-tool grinders, thirty-two years ;
spring-knife and file-grinders, thirty-five years; and saw and
sickle-grinders, thirty-eight years.

The cause of this . excessive mortality will be apparent, if
you Avill now examine this table of figures. It shows that
in every hundred sick among the needle-makers, seventy are
consumptive ; and that among the file-makers, sixty-two in the
hundred are consumptive; and, taking the steel-grinders all round,
rather over forty in the hundred are consumptive.

It is a recognised fact that, in these particular branches, the
quantity of dust is not only excessive, but finely comminuted, and
the amount of injury inflicted by it, is, on that account greater.
The eflfects of metallic dust on the lungs are, in the first instance,
only mechanical, but afterwards, by their continued irritation of
the organs, ulceration is induced, which terminates in consumption.

The next group of workers, includes those who are exposed
to the action of copper-dust. It comprehends the lithographers,
moulders, engravers, &c. ; and it will be observed that, while
the hurtful effects of the inhaled dust of this metal are more
uniformly distributed over each class, consumption is here also,
as among the steel-grinders, the predominant disease.

In every one hundred sick lithographers, one half nearly is
consumptive (48-0).

The moulders and watch-makers have each thirty-six, and the
engravers twenty- six cases of consumption per hundred. The
average duration of the life of the entire class is about forty-eight
years.

Lead-miners, painters, plumbers, workers in white lead, and
occasionally compositors, and all who work with lead, are exposed
to the risk of poisoning by that metal. The symptoms generally
are those of some form^of paralysis.

The most frequent and best known of those kinds of paralysis
are lead-palsy, painters-colic, and wrist-drop. White-lead is that
form of the metal most generally used. It is the chief ingredient
in paint, and largely enters into the composition of enamel-colours

MINERAL DUST AND MOETALITY.

enamels, and glazes. The glazing, which is, as you are aware,
an important branch of industry carried on in potteries, is often
attended with serious consequences. And in the enamelling arts,
in which lead is used, there is always considerable risk to the
operatives.

By comparing the table which shows the effect of lead dust as
a cause of consumption, you will observe, that it is less productive
of that disease than are the effects of copper dust.

It is, nevertheless, the cause of an excessive mortality. Thirty-
four type-founders, and twenty-five each of the dyers and
enamellers die of it in every hundred of each class. The painters
and printers follow Avith a mortality of twenty-four and of twenty-
one per hundred respectively.

The average life of this class is probably not over forty-eight
years.

. We now turn to the second head of our subject : —

THE EFFECTS OF MINERAL DUST.

The table under this heading furnishes a list of the chief
industries, in the carrying on of which the workmen are injured
by the dust — in this case mineral — emitted during the manufac-
turing processes.

Notoriously over-topping all the other dusty occupations in
their effects upon life and health, are those of the grind-stone
makers, flint cutters, and glass polishers.

The conditions, under which their work is carried on, are, in the
highest degree, favourable to the production of pulmonary disease.

They work in an atmosphere loaded with sharp spiculse, which
lacerate the lungs, and quickly induce consumptive disease.

Every grind-stone maker is cut down with it at, or soon after,
the age of twenty-four. Hardly one escapes.

The flint-cutter and glass-polisher have each eighty deaths, per
hundred sick, of consumption, and their average life is under
thirty years. Again the stone-cutters — a term equivalent to that
of our stone-masons (not builders), terminate their average life
at the age of thirty-six years— thirty-six, in every hundred sick,
being consumptive. A glance at the rest of the column will

TOBACCO-WORKEK, WEAVER, AND JOINER.

at once inform you what accurs to the artificers employed in
the other branches of this same group.

THE EFFECTS OF VEaETABLE-DUST.

The occupations, which are productive of vegetable-dust, in-
clude a somewhat promiscuous and apparently incongruous variety
of Avorkers. Among these we have the cigar-maker, and the
tobacco and snufF-worker. Although they enjoy ah average life
of fifty-five years, they nevertheless, head the list with thirty-six
cases of consumption in every hundred. This unexpected result
is, doubtless, owing chiefly to the irritant effects of tobacco-dust
on the lungs ; but in some degree, I am of opinion, to the chemical
ingredients superadded during the manufacturing processes.
Amongst the different classes of workers in textile fabrics, the
weavers, engaged in the cotton, flax, and hemp branches, are un-
questionably the chief sufferers. The mortality from consump-
tion, at one period, was so great as to lead the Privy Council
to inquire into its causes. Dr Greenhow, who undertook
the investigation, showed that it was during the preparatory
processes, that most dust was given off", and the greater amount
of disease engendered. These processes are known as " hackling,''
" carding," " sorting," and " dressing." *

It is stated, on the best authority, that three-fifths of the flax
mill-workers of Belfast — the chief centre of that textile manufac-
ture— are consumptive. In other words, sixty in every hundred
die of that disease.t

The average life of the Aveavers of this restricted class is
forty-four years, whilst that of weavers in general is about fifty-
seven.

Carpenters, joiners, and cabinet-makers, are aff'ected by their
dusty occupations — each group having fourteen consumptive cases
in every hundred. These facts aff'ord conclusive evidence that
their work is considerably less hazardous than that of the stone-
masons. I find it generally, but erroneously stated, and taken
for granted, that the risks of the former class are equal to those

* Vide Report of the Medical Officer of the Privy Council for 1858-60.
t Vide Essay on Health of Belfast by Dr Purdon.

MTLLER, BAKER, AND COAL-MINER.

of the latter. The average length of the lives of the two classes
respectively is a further proof of this mistaken view— that of the
carpenters, joiners, and cabinet-makers being forty-nine years, as
compared with thirty-six years of the stone-masons.

Compare now the operations carried on by the flour-miller with
that of the grindstone maker, or of the needle-grinder. The
atmosphere of a flour-mill is, certainly, much more dusty than that
of the workshop in which grindstone making or needle-grinding
goes on, but you will not fail to mark the great disparity in the
effects of the diff'erent sorts of the dust. In every hundred of
sick millers, ten are consumptive, and his average life is forty-
seven years.

The bread-baker is on a parity with the miller as regards his
average length of life, but his occupation is less productive of con-
sumption.

While flour-dust is not, in these occupations, a suflBiciently
powerful factor to make consumption the predominant malady, it,
nevertheless, conspires with the unfavourable surroundings of the
workmen to produce other ailments scarcely less mischievous.
Thus the miller, owing to the draughty nature of the premises in
which he is accustomed to work, together with the irritation in-
duced in the lungs by the inhaled flour, contracts a liability to
acute inflammation of the pulmonary organs, from which, his class
sufi"ers in the proportion of twenty in the hundred. The baker
again, immured for the most part in an underground workshop, for
twelve or fourteen hours a-day, in an over-heated air, laden with
flour-dust, often tainted with the poison of coal or sewer-gas,
acquires a liability to acute disorders of the air-passages — chiefly
bronchitis, in the ratio of thirty in the hundred. This, in his case,
becomes the predominating and fatal malady. It is interesting
and instructive to notice the last-named occupation on this table.

It is generally believed that the coal-miner's occupation is one
most highly productive of pulmonary disease, and on that supposi-
tion, when consumption occurs in the coal-miner, it is designated
" miner 's-phthisis." I feel bound to state that in my experience —
hospital and otherwise — I have not been able to confirm this
prevalent belief, nor do I believe it to be well-founded.

IMMUNITY OF THE COAL-MINER.

In every case of so-called " miner's-phthisis " which I have seen,
there has been a distinct family-history of the disease.

A man predisposed hereditarily to consumption, developes it,
not more readily as a coal-miner, than in any other employment.
The black expectoration seen in miner's consumption, proves no
more than that the coal-dust has reached the lungs — certainly not
that it is the cause of the disease. Coal-dust — or, to call it by its
proper name— carbon, from its highly antiseptic properties, acts
as an excellent protective to the pulmonary organs. The figures
on the table very strikingly corroborate this view. You will
notice, perhaps with surprise, that among twelve hundred sick
miners, only one case of consumption occurs !

THE EFFECTS OF ANIMAL-DUST.

Animal-dust is evolved in the processes of brush-making and
hair-dressing, in the operations carried on by the skinner, tanner,
and hatter ; and in those of the button, harness, and clothmakers.

I allude, of course, to these occupations as they are carried on
upon a great scale in large manufacturing centres, where there
is machinery, and where workmen are massed together in large
bodies under one roof.

In such a city as this, with its limited and well-regulated in-
dustries, it is difficult to one, not directly conversant with their
details, to realise what such operations really imply. When,
for instance, I name hair-dressing as one of the occupations of
the present group, the term is intended to include all the pro-
cesses connected with the preparation of hair for its artistic and
commercial uses. So that the name, in this connection, suggests
little, if anything, in common with the comparatively healthy
avocation of the perfumer and hair-dresser familiar to us. I
may as well remark here, to prevent misunderstanding, that this
statement applies generally to all the occupations now under con-
sideration. We have already observed that the excessive
mortality prevailing among the cotton, flax, and hemp-weavers,
has its origin chiefly in the irritation induced by the contact of
shreds of these substances with the lungs.

We have all experienced, I suppose, the trouble which a

wool-sorter's disease.

hair causes when lodged in a sensitive part of the air-passages ;
and how much greater the discomfort if it happen to be a bristle
from a tooth-brush. Now, if we hold in remembrance, that it is
owing chiefly to the action of sharply cuminated particles from
bristles that the brush-maker is exposed to, the fact will suffi-
ciently account for his high death-rate of forty-nine in every
hundred, from consumptive disease.

The hair preparers— for that is their proper designation— have
also a large proportion of deaths from consumption; the number
being thirty-two per hundred. To those exposed to the eff'ects of
inhaled animal dust, there is moreover, the additional risk of
poisoning, derived from the diseased animals from which the hair
has been taken.

There is a special liability in some of the lower animals to be
attacked by a very fatal and contagious malady called anthrax.
Should the hair of the infected animals unfortunately find its
way into the market, and thence to the hands of the wool-sorter,
he is certain to be attacked by the disease, and equally so to
die of it. Special attention has lately been given to this disease,
and much light thrown upon it in connection with the occupation
called wool-sorting.*

THE EFFECTS OF GASES AND VOLATILE
EMANATIONS.

Asthmatical and bronchial afi'ections are those induced by
inhaled gases of an irritant character. When, however, such
occupations are associated with a sedentary posture and confined
air, they induce considerable consumption. Thus, straw-hat
makers, who are mostly women, are exposed to the fumes of
sulphurous acid ; and jewellers, in the refining processes, to nitrous
acid vapours. ConsumptioUj in both, prevails to the extent of
eighteen in each hundred ; and inflammation of the lungs
(pneumonia) to the extent of eight in each hundred.

Bleachers are exposed to chlorine gas and alkaline vapours.
As a class they are not generally healthy, but their average life
is comparatively good, being fifty-eight years. The operations

* We are indebted to the careful researclies of Professor Greenfield for
much of what we know of this disease.

HEALTHINESS OF CERTAIN OCCUPATIONS.

connected with soap boiling, tanning, parafine-maldng, and candle-
making, belong to this class. On account of the disagreeable
odours emitted, they are, in the Public Health Act, designated
noxious trades. It is remarkable that these occupations have,
from time inmemorial, and in all countries, ranked amongst the
healthiest of the industrial employments. The average life of
the workers is over sixty years.*

Will you notice that, in one hundred sick among the charcoal
burners, there are only two consumptives. This is the next
lowest death-rate to that of the coal-miner ; and for the reason
previously mentioned, that the carbon is protective to the
lungs. Parafine-makers, although exposed to powerful vapours,
enjoy a similar remarkable immunity from consumptive disease.
This is accounted for by the antiseptic properties of parafine.

Of those who are affected, not so much by dust, as by

THE EFFECTS OF CONSTRAINED BODILY POSITION
CONJOINED WITH DEFECTIVE VENTILATION,

we restrict our attention to three well-known classes. These
are, firstly, the needle-women of every class, including milliners
and dressmakers ; secondly, tailors ; and thirdly, shoemakers.
Their surroundings in their essential features are alike ; they all
work under the disadvantages of a sedentary and constrained bodily
posture, in over-crowded and ill-ventilated work-rooms. They are
but little addicted to out-door exercise, and their habits of dieting
are extremely faulty. From their excessive tea-drinking, they are,
with few exceptions, confirmed dyspeptics. Pale in complexion,
spare in bodily condition, they age prematurely. The women are
afflicted with anosmia, which means the loss of red blood, giddiness,
palpitation, shortness of breath, weak and trembling limbs,
and, generally, the complete suspension of those functions upon
which their health and usefulness depend. These symptoms, for
the most part, terminate in consumption, unless their occupation
is timeously reHnquished. The conditions under which they
carry on their respective employments, are so analogous that we

* It is mentioned, as a matter of history, that during the plague called
the "Sweating Sickness," tanners, curriers, and such as were employed in
unpleasant smelling businesses, all escaped infection.

MORTALITY OP SEDENTARY OCCUPATIONS,

should expect each class, in a nearly equal degree, to suffer from
the same maladies.

The results of a perfectly independent inquiry into the case of
of each class, remarkably corroborate this anticipation, as you may
readily satisfy yourselves from the appended tables.

The tailors and needle-women, you will observe, have each
nineteen deaths from consumption per hundred sick. The shoe-
makers fall short of that number only by a fraction, being 18-7.

Under the head of

THE EFFECTS OF DUST FROM POISONOUS METALS

are included workers in phosphorus, in mercury or quick-
silver, and in arsenic. Lucifer match-making is the sole occu-
pation which exposes those who work at it to the action of
phosphorus fumes. The inhalation of phosphorus vapours is
productive of a frightful disease, namely, death of the jaw bone,
necessitating its removal by a severe operation.

The prevalence of this disease led, some years ago, to an inquiry
into its cause, with the result, that a different kind of phosphorus
(amorphous), unaccompanied by these effects, was substituted.

The average life of the lucifer match-maker Avas formerly as
low as forty-four years. Work people much employed in the use
of mercury or quicksilver in the arts, are liable to a peculiar kind of
paralysis, with salivation, tremors (called "trembles" by the work-
people), and stammering. Chief among those affected in that class
are the water-gilders, when an amalgam of gold and mercury is
used. This process is now happily superseded by electro-plating ;
while, at the same time, recent improvements in looking-glass
making, further permit that branch of the art to be carried on
with comparative immunity.

The leading sufferers from mercury are now those who work in
the quicksilver mines.

Mercury, although a ponderous metal, is, nevertheless, volatile
at ordinary temperatures. Every fourth man accustomed to in-
hale its fumes dies consumptive, and the average life of the quick-
silver miner is forty-seven years.

Arsenic, besides being an invaluable medicine in the hands of

EFFECTS OF ARSENICAL DUST.

the physician, is much prized ia many of the arts for the great
brilliancy and cheapness of the colours made from its salts.

The chief of these is that pigment popularly known under the
names of Emerald-green, Brunswick, or Vienna-green. This
pigment is of two kinds, known to the chemist, the one as
Scheele's, and the other as Schweinfilrt's green.

The former contains fifty-five, and the latter fifty-eight per
cent, of white arsenic — that is to say, more than a half of the
pigment is pure arsenic.

It is from this material that wall-papers in every shade of
green, artificial flowers, fruits, feathers, dresses, &c., derive their
colour. It is estimated that in England alone, seven hundred
tons of this green are every year thrown into the market for use
in these arts.*

It is remarkable, that workmen employed in roasting the
arsenical ores, and who are much exposed to arsenical dust,
are less affected by it than others whose business it is to apply it
to its industrial uses. It is believed by Dr Guy, and other
eminent authorities, that these workmen suffer comparatively
little, if at all. You will however see, from the tables, that this
conclusion is not warranted by the facts of the case. In every one
hundred sick among the arsenic makers, eleven are consumptive,
and their average life is forty-seven years — being the same as that
of the quicksilver miners. If you Avill now compare these facts
with the case of those who are engaged in the conversion of the
arsenic into arsenical pigments, it will be seen that every fourth
man among the latter is consumptive (25-0) ; and his average life,
is in a proportional degree, lessened. Once more, let me call
your attention to the fact, that the artificial flower maker has a
still greater mortality— his death rate being one in three (36-0)
or thirty-six in every hundred sick.

Let us here pause and for a moment contemplate some of the
possible results which may attend the introduction of such sub-
stances into our social and domestic usages. Here is a piece of
a favourite and much-used arsenical wall-paper. An ordinary
sized room, with one thousand square feet of wall surface covered
with it, would contain twenty thousand grains of arsenic.

* "Manual of Hygiene," Cameron.

ARSENICAL POISONING IN ARTS.

The arsenic is held loosely adherent to the paper, and is easily
detached and diffused through the room as dust. This dust,
found on the shelves, and on other articles in the room, when
analysed, yields arsenic.

All those green papers, so much used in general merchandise,
contain arsenic in varying proportions. Size-greens, sold at a
cheap price, are now much in vogue for size-painting walls. They
vary in strength from seven to thirty-six grains of arsenic in each
square foot of wall. A child's picture-book has been found to
contain fifty grains; but what shall we say of those bright
poisonous colours so alluring to the young, w^hich garnish their
toys, and even sweetmeats 1 Here is an article belonging to the
textile fabrics — one of many treated to the arsenical process. A
dress of this material, as now made, contains two thousand grains
of arsenic. An artificial wreath, such as I show you, contains pro-
bably not less than ten grains of the poison.*

The case of a young woman of nineteen is reported, who
died under symptoms of arsenical poisoning after being eighteen
months employed in artificial green flower making.! Examina-
tion after death showed that the poison had penetrated the
tissues.

It has been well said that, the feeling which prompts people to
keep off the appearances of age as long as possible, sometimes
leads them into practices which shorten life. Among the
numerous articles used in this way, we must include those
nostrums widely advertised as hair-restorers, which are reputed
to preserve the pristine colour of the hair, or to restore it if lost.
These dyes, for the most part, contain lead, and numerous cases
of poisoning by their use are recorded, face-enamelling — the
occupation of those artistes who profess to beautify their clients
for ever — is liable to similar objections.

Cochineal, supposed to be harmless, and employed to give
a peachy bloom to the cheek, contains, as stated by Tardieu,
arsenic, mercury, and lead. And even the present fashionable

* See excellent article on arsenic in " Common Things," by Dr Steven-
s on Macadam. — Smiitary Record.

t " Public Hygiene," Cameron, Dublin.

GERMANY AND POISONOUS PRODUCTS.

colours derived from coraline red, and aniline, are not free from
suspicion.

Having regard to the effects produced upon the health of those
employed in the poisonous arts and manufactures, and to the
grave consequences resulting to the community from their
unrestricted use, the question naturally arises, is it right, or
desirable to allow the manufacture and sale of articles attended
with so much risk? Arsenic, as such, cannot be procured
without certain legal precautions, such as a medical certificate,
and the name and address of the purchaser ; but I have j ast said
that seven hundred tons of arsenic — a moderate estimate of the
quantity — in England alone are sold as pigments, some of them
containing more than 50 per cent of arsenic.

Quantities of these may be bought for a few pence without
any question being raised. No one, surely, would object to the
prohibition of this traffic on the ground that such an act would
infringe the liberty of the subject ! Might it not, on the
contrary, with more reason, be alleged that our liberty suffers
by the legalised continuance of such a state of matters 1 " An
excess of liberty in any commonwealth," remarks the great
Eoman commentator,* " degenerates to the opposite extreme in
licentiousness and tyranny." It may be instructive to ascertain
how this subject has been dealt with by some of our enlight-
ened neighbours on the Continent. The German Government,
for example, deeply impressed with the conviction that the
manufacture and sale of such articles were incompatible with the
liberty and safety of the subject, on the 1st May 1882, laid
before their Parliament a decree of which I give, in effect, the
substance. The preamble states that the object of the Act is the
prohibition of poisonous pigments ; and the following substances
are described as coming within the meaning of the Act, namely,
antimony, arsenic, barium, lead, cromium, cadmium, copper,
mercury, zinc, tin, gamboge, and picric acid. Secondly, the
preserving and packing of food stuffs intended 'Jor sale, in
Avrappers coloured with the above cited poisonous colours, are
prohibited. Thirdly, the employment of poisonous colours,

* Tacitus.

DUST AND CONSUMPTION.

enumerated in the Act, is prohibited in the manufacture of
playthings. Fourthly, the use of arsenical colours for the manu-
facture of paper-hangings, or for materials of dress, is prohibited.
Fifthly, the sale of food stuffs, or food products, preserved or
packed contrary to these regulations, is prohibited. Sixthly,
the enactment shall come into operation on the 1st of April 1883.
Now, you will perhaps characterise this proceeding on the part
of the German government, as a bold, if not a sweeping and
summary measure. Let us see what came of it. Germany is, as
you are aware, the great manufacturing workshop of these pig-
ments, and of the arts to which they are applied. Here, then, is
an act that threatened the extinction of these industries, with
its consequent widespread commercial ruin.

In view of this disaster, we may believe there were no
lack of appeals, remonstrances, and even threatenings. The
government, however, remained firm in its determination to
waive every consideration except those which had regard to the
best welfare of the people. Now notice what comes of doing
what is right regardless of consequences. The dreaded 1st
of April — the day on which the Act would come into force
— at length arrived, but with it, not the expected ruin. How
was this ] How often — as in this case — has necessity proved
the "mother of invention," especially when it touches that
sacred depository of the public conscience — the pocket 1 In
short, before the fated day, by the joint aid of money and
science, neAv and poisonless pigments were devised, tried, and
found to fully meet all the requirements of the case. Thus,
Germany at this moment, has the proud satisfaction of having
initiated a great sanitary reform.

You have not, I am sure, failed to be struck with the fact that
these effects of unhealthy occupations culminate, in an extra-
ordinary degree, in the production of one particular disease. It
is unfortunately the most prevalent and fatal of our maladies ;
and it is on that account that I have chosen pulmonary con-
sumption as the crucial disease by which to test the ill effects of
these occupations.

A high death-rate, amongst any class, from consumption, im-

NUMBER OF WORKMEN AFFECTED.

plies a coincidently increased number of deaths from most other
disorders. The statistical tables afford evidence in corrobora-
tion of this fact. The proofs abeady submitted have sufficiently,
I doubt not, impressed you with the extent of the evil to which
they are intended to direct your attention. It is a question,
to which attaches great interest, to know how many workmen
in the United Kingdom are, by means of their employments,
directly exposed to these effects. Have we any means of arriving
at the knowledge of this important fact 1 We are certainly with-
out any positive data to guide us, but I shall endeavour to arrive,
as nearly as possible, at a correct estimate of their numbers.

Taking then, as the basis of our calculation, the recently pub-
lished census for the ten years previous to 1881, we find that the
whole industrial class has, during that period, increased by one
hundred and eighty-one thousand; and that in their aggregate
strength, they at present constitute a fourth part of the entire
population of the United Kingdom (24-97). That gives them, as
you wiU see, a numerical strength, say, of eight millions, five
hundred thousand : — the entire population of the United King-
dom being thirty-four millions, six hundred and twenty-eight
thousand, three hundred and thirty-eight.

Carefully scanning the various employments embraced by the
entire industrial class, I reckon that a proportion of one-tenth of
their number suffers — that is to say, eight hundred and fifty
thousand are thus exposed to the injurious effects of their occupa-
tions. The first and immediate effect of this is, that every
member of this eight hundred and fifty thousand has his life
reduced to an average of forty-five years.

Taking fifty-five years as a fair average standard to which each
ought in favourable surroundings to attain, it follows that every
one of these workmen loses ten years of his working life. Now
we may assume that a Avorking man enters on active employment
at an age not later than fifteen, and from this it will appear that
the average lifetime after beginning work is about forty years.
But in the case of those whose average duration of life does not
extend beyond the average of forty-five, there will be only thirty
years of life after beginning work, or three-fourths of the normal
period. It therefore follows, as three times fifteen complete the

IMPOVERISHMKNT AND HEREDITARY DISEASE.

average life of forty-five, that every fourth man, of the number above
stated, drops out of account as completely as if he had not
existed. This represents a loss of two hundred and twelve thou-
sand, five hundred— a number nearly equal to the population of
this city — in each successive group of eight hundred and fifty thou-
sand men. But the same cause which removes this number of work-
men leaves behind, at least, that number of persons who were
dependent upon tliem, and who are thus impoverished.

There can be no question that two-thirds, if not the whole, of
that number are not only impoverished but pauperised, and in
the end find their way on to the parish roll. The origin of our
pauperism is one of the vexed questions of the hour. At a con-
ference held lately at Aberdeen, intemperance and improvidence
were, by common agreement, believed to be its chief causes. The
advocates of such views would, I am disposed to think, entrench
themselves in a more logical position, besides having a founda-
tion of incontrovertible facts to rest upon, were they to accept
the explanation I have now offered. Intemperance and improvi-
dence are not causes, but the effects of causes which require to be
themselves accounted for.

But the mischief does not stop here. It is certain, that each
of the two hundred and twelve thousand, five hundred, will, on a
moderate estimate, leave at least one descendant, who will pro-
bably, in course of time, develop the hereditary disease of
which the parent died. We very safely assume that each
of the nvimber stated has died of pulmonary consumption.
Here then, we have brought before us most probably, the chief
cause which accounts for the increase of consumption in this
country. The question is often asked, where does all this disease
come from 1 And there is, doubtless, an implied reproach on medi-
cal science and on the healing art, Avhen it is said, that they are
comparatively powerless in dealing with it. I would only here
take occasion to say in regard to that, that in the case of no
other disease has there been so much lately added to our know-
ledge that is substantial alike as to its nature and treatment.
But fed, as it perennially is, by constant streams from those
quarters which may be regarded as its natural breeding places, is
it not mockery to speak of dealing with it by means of treatment ?

INCBEASE OP CONSUMPTION.

In the face of an evil of such growing magnitude, there cannot,
I afl5rm, be any remedy short of its prevention. In the mean-
time, however, those who, in increasing numbers, are seeking our
help must be cared for. The diflSculty experienced, in doing this,
is only really known to medical men, and more so to those
connected with such an Hospital as our Royal Infirmary. Drawn
to it, no doubt, by its fame, and to Edinburgh by the known
benevolence of its citizens, we have to encounter the task daily of
sending away crowds who cannot be admitted to its wards. You
are, I daresay, aware that it is barely within the scope of that
Institution to receive cases of the kind, partly, because it is a
serious disadvantage to the other patients on account of
the troublesome night cough with which such sufferers are
afflicted. Nevertheless, be it told, alike to the credit of
the Managers and of the Medical Officers, that there is not a
ward which has not its full complement of them ; but, I need not
say that this is a most undesirable state of matters. Let me here
plead guilty to having gone a little aside from the main drift
of my theme to speak of this matter. I have taken the oppor-
tunity of doing so that I might direct attention to, and perhaps
awaken an interest in, the subject. Whilst London has its half
dozen hospitals for consumptive cases, and other considerable
cities are not without some provision for them, Edinburgh, which
owns a great medical school, is, it must be confessed, in the
position of not having a single bed set apart for so necessary an
object ! It would be a great and truly useful work to devote an
edifice to so benevolent a purpose, and to the good Samaritan
who should do so, there would be the reward— I say, not of the
approbation of his fellows, or the thanks of the medical profession,
or the lasting gratitude of those who would reap its benefits — but
the enviable consciousness of a deed that would perpetuate the
relief of a sadly numerous and interesting class of sufferers.
We have now to speak of

THE MEANS OF PREVENTING THE EFFECTS OP
UNHEALTHY OCCUPATIONS.

_ You will have observed that, in the case of almost every occupa-
tion I have spoken of, the injury is inflicted through the agency

MEANS OP PREVENTION.

of inhaled particles, or by personal contact, on the part of the
worker, with poisonous substances, or by the breathing of irritant
gases, or vapours, exhaled from them. In order to change the
character of an unhealthy, to a healthy occupation, it is only
necessary to free the air of its suspended matter, such as dust or
other foreign bodies. To accomplish this object, many contriv-
ances have been devised and tried ; but, as we shall see, without
their having conferred any substantial benefit. The steel-grinders
are provided with the magnetized mre-gauze respirator, which
was proved to effectually prevent access of steel-dust to the lungs.
Stone-cutters and millstone-grinders are Kkewise provided with a
respirator, which would equally well protect them ; while the flax-
workers of the north of Ireland are familiar with an instrument
known as the "Baker respirator," specially designed for their
benefit.

The efficiency of an ingenious respirator, constructed to enable
the London Fire Brigade to inhale an atmosphere of dense smoke,
otherwise suffocating, was some years ago devised and successfully
tested by Professor Tyndal. It is made of cotton wool, moistened
with glycerine, and mixed with pieces of charcoal.

Here is another instrument, a respirator, which I devised
some time ago for a different purpose ; it is more complex, but
the same in the principle of its construction as those I have
named to you ; its objects are to warm, medicate, and filter the air
in its passage to the pulmonary organs. From what I have said,
you will have perceived that there is really no practical difficulty
in depurating the air of its dust, and other hurtful foreign
matter, by means of mechanical adaptations such as I have
spoken of. The difficulty, as we shall afterwards see, is of
another kind. In my lecture on " Preventible Diseases " to the
Health Society, I took the opportunity, by means of an interest-
ing experiment, to show you the important fact that cotton-
wool held over the mouth and nostrils effectually frees the air of
its suspended particles. I have had this cotton-wool prepared so
as to remove its impurities, and at the same time enhance its
absorbing property. In virtue of these combined properties,
it is not only an efficient dust filter, but also, by absorbing

VENTILATION IN WORKSHOPS.

them, arrests the access of noxious vapours to the lungs. These
qualities are still further improved by the wool being pressed into a
kind of loose cloth such as I show you. Again, chemical and other
vapours are rendered comparatively harmless when inhaled through
•cotton. The vapour of mercury may be made less hurtful to the
workmen if the floors of the workshops are sprinkled with
ammonia. In the case of all, whose work brings them into con-
tact with poisonous metals, certain obvious precautions are neces-
sary; such as that the hands and mouth should be washed before
eating, and the wearing of a washable overall dress. By all who
work among lead, water acidulated with sulphuric acid, should be
taken freely as drink. It need hardly be added, that, to the
worker in poisonous metals or arts, the constant use of the bath
is indispensable to his safety. Efficient, as are these appliances
when made use of, we must nevertheless regard them as sub-
sidiary to the paramount question of ventilation. In a time,
such as ours, when sanitary knowledge is as popular as it is
widely diffused, it would be idle to argue that a certain quantity
of pure air requires to be inhaled in a given period. The standard
amount necessary for each individual to support life and maintain
health is, as you know, five hundred cubic feet daily; or, to
express it differently, three thousand gallons during that period.
In other words, the imperative requirements of health impose on
each of us the necessity of inhaling two gallons of good air every
minute of our lives. To infringe this rule would be to court
disease; and to live in the habitual disregard of it to en-
counter premature death. To impress this fact upon your
memory, it will only be needful to mention a case or two in point.

Dr Edward Smith, the distinguished sanitarian, in his report
to the Government on the condition of the London tailors'
workrooms, states, that the cubic space in these ill-ventilated
places allowed to each operative and the gas-light, is one hundred
and fifty-six feet. It is necessary to explain that each burner
consumes about as much as an individual. Dr Smith states that
the death-rate of the tailors working in these rooms is one-third
greater than of persons of the same ages who pursue their occu-
pations in good air. Dr Guy, in an inquiry into the health of

WORKMEN AND AMELIORATIONS,

the London bakers, points out that thirty-one of them per hun-
dred are consumptive, a fact, which he ascribes to their ill-venti-
lated workshops. You are now in a position, from what I have
already stated, to modify these views of Dr E. Smith and Dr
Guy, as to the degree of mortality and its causes prevailing
among the tailors and bakers. Referring to a London printing
oflBce, in which, only two hundred and two cubic feet of breathing
space were allowed to each man, the same authority remarks that
the deaths from consumption followed as fast on each other as
deaths from some contagious fever.

It was no doubt this frequency of death from that disease,
occurring in ill-ventilated workrooms, that j&rst led to the belief
that consumption was an infectious malady.

I do not say — for I cannot speak from personal knowledge of the
fact — that, in our great manufacturing workshops, the statutory
amount of space is not given, but I do affirm, that, it would be an
altogether inadequate space in an atmosphere constantly re-
plenished with pernicious materials derived from the manufactur-
ing operations.

It must be obvious that their requirements are of a different
kind from those of a dormitory or dwelling, or the wards of an
hospital, and that the question of the proper ventilation of these
places cannot be settled by the off-hand rule of so much space to
so many individuals. The problem to be solved is this : how
to environ each worker in the prosecution of his work with a pure
atmosphere 1 It is not for me to undertake the solution of this
problem, because I hold that to be a matter for which the responsi-
bility rests upon the Legislature. I am nevertheless free to express
my confident conviction that this result appears to me to be only
a question of certain, simple, practical, mechanical adjustments,
requiring no effort of genius, or even outlay, where there is so
much already existing machinery.

Let us pause and ask here : — how do those who have most to gain
or lose regard those proposed ameliorations which we have been
considering ? It would appear, that in some instances, they are not
viewed with favour, and, owing to this want of unanimity, it is to
be regretted, that they have not been generally adopted. Any

NEED OP ADDITIONAL LEGISLATION.

changes of the kind indicated, again it is alleged, are objected to
on the ground that the effects would be to increase the number of
working hands, cheapen labour, and make it more scarce. But
this feeling is, I believe, chiefly confined to the steel grinders. I
hope you will all agree with me that this is an altogether mis-
taken view of the case ; and that feelings, of whatever kind, which
thus stand in the way of their using the means provided for their
benefit, ought not to be encouraged. Past experience has made it
quite evident that all such measures ought, as in the case of the
Davy safety-lamp, to be made compulsory.

Have we any means of knowing how such matters are
viewed by the employers 1 In the first place, it is certain that
they are not themselves fully aware of the extent of the mischief ;
and secondly, that, although having at heart the best wishes
for their people's welfare, their good intentions are apt to be
frustrated by conflicting interests, arising out of rivalry and in-
creasing competition, with reduced and precarious profits ; and
thirdly, they do not feel that the onus rests upon them of taking
the initiative — the legislature having, by means of the Factory
Acts, and otherwise, assumed the responsibility of regulating
such matters.

It would seem, then, that we must necessarily fall back upon
government regulation and control as the only available remedies
for these evils. Previous to the passing of the Factory Acts the
ill effects of their work upon the health of the workmen were so
notorious that, in response to the wish of the country, a Com-
mission was appointed in 1833 to inquire into their causes. The
Factory Acts were, at that time, undoubtedly a great boon to the
people J but it is evident that they are not now fitted to accom-
plish the object for which they were intended in the sanitary
regulation of our industries.

The facts which I have eliminated and brought before you,
fully, I think, prove this, and also, that an inquiry is urgently
necessary. The vast increase in the country's industrial resources
and population since 1833, together with corresponding improve-
ments in machinery and in chemical appliances, have altered the
entire complexion of our industrial occupations, and have led to

WORKMEN AND PUBLIC HEALTH.

insanitary conditions which demand a remedy as much as did those
for the removal of which the Factory Acts were originally passed.

It is, however, neither consistent with our traditions nor
experience to believe that measures of the desired kind will be
vouchsafed without some decided expression of public opinion,
perhaps pressure, or, it may even be a lengthened process of State
education. To the class most interested,' I would venture to say,
— remember that union is strength, and that you cannot unite for
the attainment of a more desirable or legitimate object than the
protecting of your health and the surrounding of it with every
possible safeguard. I am glad to observe signs that the workmen
of this country are about to assume their proper position in
relation to sanitary questions affecting them ; and, perhaps, I may
be allowed to quote an instance which I deem worthyiof example.
The Trades' Union Congress, at their meeting held in Dublin in
September 1880, passed the following resolution :—" That the
Parliamentary Committee be requested to continue their exertions
on behalf of those engaged in wool-sorting, with the object of
attaining for them protection against blood-poisoning caused by
the use of imported wool-hair infected with a malignant and
dangerous disease, and to which wool-sorters are liable in pursuing
their occupations." While addressing you on the effects of animal
dust, associated with a specific poison, you will doubtless remem-
ber that I specially directed your attention to this disease.
Whether we regard the terms in which this resolution is couched,
or the dignified attitude of the Congress in passing it, it will, I
am sure, commend itself to your respect, and I feel justified in
congratulating the Congress on a step which marks a new depar-
ture in their relation to such questions.

In an address delivered to the British Association last autumn
by a well-known English professor,* the working-classes are
advised that, if they would reach a higher social platform, they
must summon resolution to raise themselves above what is depres-
sing in their immediate surroundings. Let me say frankly that in
reference to the whole class whose occupations form the subject
of this lecture, I regard the exhortation as simply impractic-

* Profefsor Leone Levi.

STATE EDUCATION.

able, so long as the real cause of that depression continues to exist ;
and that cause is to be found in the unhealthy character of these
occupations. Will you, with me, take a momentary survey of
what the surroundings are 1

The strongest and hardiest among the workers are soon sensible
that there is a loss of energy. Then, as the seeds of their insidious
malady are being daily sown, there steals over them a lethargy
and apathy which no effort of will can bid away.

Then comes loss of appetite and the increasing burden of their
daily toil to which they feel unequal. This is the moment of
supreme trial to most of them, for it is then that they seek to rally
their sinking spirits and failing strength by recourse to stimulants.
There is not, I maintain, any a priori cause why our countrymen,
more than others, should be addicted to intemperance, except it be
through their unhealthy occupations superinducing a condition —
a disease I call it — which craves for it. It might be well if
our social reformers would regard our prevailing intemperance
from this point of view, for I am satisfied that it is an incredibly
fruitful, if not the chief, source of it.

I find that I have inadvertently used an expression to which
attaches a kind of political significance. Let me at once disavow
any such intention in speaking of "educating" the State, and, at
the same time, explain to you what I mean by that expression.

It is almost trite to remark that every nation has its own indi-
vidual life history. Its childhood, youth, and maturity are each
a period fraught with its own peculiar and fitting education.
That part of history, Avhich shows us how those lessons have been
learnt upon which a nation's ultimate stability depends, is not the
least instructive. Let us, for example, take the matter of national
health. We have it on the authority of Niebuhr that the preval-
ence of plagues, more than ethical or political causes, influenced the
destinies of such cities as Florence and Athens; and, that the de-
cline and fall of such an empire, as the Roman, were brought about,
not, as we are accustomed to believe, by a species of moral dry-rot,
but by the pestilences which carried off the adult male population,
and left the then proud mistress of the world an easy prey to the
barbarian. Who can read the long continuing death-tax of our

HISTORICAL RETROSPECT.

own nation, without asking, what has saved her from a like fate 1
A brief historical retrospect will show you this. During the four-
teenth century our ancestors had to grapple with that fierce plague
named the "Black Death," which destroyed nine out of every ten
whom it attacked. The fifteenth and sixteenth centuries found
them struggling with the " Sweating Sickness," killing its victims
in a few hours, and leaving a heavy death-roll. For three cen-
turies prior to the close of the eighteenth, that terrible distemper
called "Gaol Fever," taking its origin in our prisons, never ceased
to infect the Army, Navy, and the civil population. Another
plague, called the Oriental, prevailed through much of the six-
teenth and seventeenth centuries ; its smallest death-toll being one
in five, but often three in five. Then, there followed Asiatic cholera,
with its attendant epidemic dysentry ; and lastly, unvaccinated
small-pox, not less ghastly in its death-rate or repulsive con-
comitants. This dark catalogue of pestilences was more or less
associated with those fevers confusedly known under the various
names of spotted, typhus, relapsing, famine, and typhoid. With
our greater light, it is difficult to understand why the nation so
slowly awoke to the full comprehension of the enormous jeopardy
and cost of these invasions. It was only with the advent of John
Howard in 1794 that there came also the dawn of an epoch
marked by a regard to public health, whose growth and influence
are, I believe, the causes of our being now in the van of civiliza-
tion. You all doubtless know what is meant by John Howard's
parliamentary triumph. Single handed he obtained — at a time
when such concessions were a great victory — an Act to inquire
into the state of our prisons. What were the results of this Act?
These pestilential dens, which, for centuries, had poisoned every
stream of our national life, were abolished, and, as a matter of
fact, our prisons are now the healthiest places in the country.
What I wish you to particularly note here is the fact that the
second step in this great reform was brought about by an Act of
the Legislature — the first being that of Howard's representation
of the facts.

Two years later, there occurred another Parliamentary triumph
when the discoverer of vaccination was voted £30,000 to extend the

COMPARATIVE MORTALITY.

benefits of his discovery. Here also, you will again observe, that
an Act of the Legislature is the crowning event. I have said that
I am arguing on the assumption that our unhealthy occupations
ought to be dealt with by legislative measures. I am accordingly
adducing historical evidence of the efficacy of well-directed sani-
tary legislation, while I am, at the same time, seeking to impress
upon you the desirableness, and even urgency, of your representing
to the Legislature such considerations as will satisfy it that fresh
and more cogent measures are needed. The beneficial effects
resulting from such measures are constantly brought under our
attention. I select one out of a multitude of instances. One of
the household regiments — the Foot Guards — was found to have
more deaths from consumption than prevailed among the soldiers
of the Horse Guards. The former had thirteen deaths per
thousand, the latter seven. The Army Sanitary Commission
appointed to inquire into the case, reported, that the cause of
the discrepancy was a deficiency in the breathing space allowed
to the former. The defect was no sooner rectified than the
abnormal death-rate disappeared.

Taking the whole of the occupations, to whose condition
I have specially directed your attention, I find, that twenty-six
of these, in every hundred, die of consumption ; while the pro-
portion of deaths from that disease among the general population
is only twelve in the hundred.*

It is a matter of history that this long-continued State educa-
tion, in its reference to national health, culminated on the 1st of
June 1774, when Lord Howe achieved the all-decisive victory
which gave to Britain the supremacy of the seas. On that
memorable occasion, for the first time in the annals of our naval
engagements, perfectly healthy crews, numbering in all seventeen
thousand two hundred and forty-one, went into action against
the more heavily armoured and manned fleet of the enemy,
but with this difference — that the enemy's crews were less

* As this 12 per cent, among the general population includes all deaths
from consumption arising from the unhealthy occupations referred to, it
would be necessary in order to institute a fair comparison to exclude the
latter. The result would then show a still greater disparity, as the rate
among the general population would then be reduced.to ten in the hundred
■at the outside.

PECUNIARY LOSS TO THE STATE.

efficient through disease. It may be fairly questioned whether
we owe the victory more to Lord Howe than to his physician ,
Dr Trotter, to whose discretion he wisely left the entire sanitary
equipment of the fleet. But, in any case, its immediate and ulti-
mate effects were not less notable in their sanitary than in their
political and diplomatic consequences.

It is my contention, as you will perceive, that our great opera-
tive industrial classes are entitled, equally with the combatant,
to be cared for and protected, as to their health, in the pursuit of
their avocations. They have a claim to it in respect of their
numbers, social and political standing, and usefulness. They are
the back-bone and sinews of the nation's strength, and its capital
and wealth makers.

The number of men withdrawn from peaceful occupations for
fighting purposes, during the whole of the twenty-two years that
our country was engaged in the revolutionary wars, did not
exceed a quarter of a million. I estimate that a quarter of a
million nearly of these workmen is continuously lost to the State
— a loss which covers the whole period of each man's work-
ing life. For a moment, consider the effects of this from a
merely economical point of view. Taking the figures, as I have
already given them, to be two hundred and twelve thousand,,
five hundred, and reckoning each man's wages at one pound
a week, there is thus a yearly loss in wages to the industrial
wage class amounting to upwards of eleven million pounds ! * If
we now add to this the loss of the wealth that would have
been produced by the workers so cast off, there results the grand
total of thirteen millions, seven hundred and fifty thousand pounds,
the whole of which is annually lost to the 'country ! In point of
fact, that sum, would, in about fifty-seven years, clear off the
whole of the national debt. So much for the money aspect of the
question. But what of the needless waste of life and its atten-
dant sickness : of the consequent impoverishment, pauperism, and
demoralisation; and the increasing legacy of hereditary disease?

Were I to attempt the role of the historic Glendower, and
summon spirits from the vasty deep, my performance would, I

• Taking into account the natural increase of the industrial population,
there will be a yearly increase to this money loss of over £20,000.

DUTY OF THE LEGISLATURE.

fear, be as unproductive as that of the original. But will you
permit me, in form at least, to invoke the shade of our great
countryman — might I not say townsman? — Adam Smith. "We
should not certainly expect the renowned economist to indite
a new "wealth of nations," from a modern stand-point, a
century after his great work was given to the world ; for what
he wrote in 1 776 appears to have been given for all time. But look-
ing back, and gathering up the lessons of the past, one can imagine
that he would, at least, add a prefatory note somewhat in these
words; that is, if I may be permitted to suggest words to so great
an oracle : — There are two primary and fundamental considerations
upon which national stability and permanency rest. The first
regards the health of the people — the other its education. Any
system of government, without full provision being made for
these, will be incomplete : and, in regard to the former, the best
guarantee of a nation's security will be wanting. Therefore,
above all things, let no government, in its administrative capacity,
be without its health department, presided over by a wise and
energetic Health Minister, whose supreme duty it shall be to create
and to vigilantly administer laws, the aim of which shall be to pro-
tect the health of every subject, and especially to surround that
of the dependent industrial population, with every possible safe-
guard. Then, addressing his own countrymen, might we not sup-
pose the philosopher, with increased emphasis, to add : — A nation,
such as ours, of thirty-four millions, with a vast manufacturing in-
dustry, a most busy and flourishing commerce, an Indian Empire
to govern and maintain, colonies to attract the most vigorous and
enterprising of our people, great fortresses to man and defend,
cannot aflTord to waste the lives of its citizens, any more than those
whom it has chosen and trained to fight its battles. Are not
labour and capital the two pillars upon which a free common-
wealth rests ? Disease paralyses labour and wastes capital. It
ought then to be the primary object of an enlightened State to
prevent disease, preserve health, and prolong life ; and to main-
tain the whole people in the highest efficiency alike for the
labours of peace, or the struggles of war.*
* For part of closing sentence vide " Public Health," passim, Dr Guy.

TABLES

Showing the Effect of Different Kinds of Dust upon
THE Health of the Workers.*

TABLE I.
Metallic Dust,

In every 100 Patients
among

Needlemakers,
Filemakers,
Grinders (steel).
Steel Dust -I Pinmakers,
Cutlers,
Lock-Smiths,
Farriers, .

Lithographers,
Moulders, .
Watchmakers,
Copper Dust ■{ Engravers,
1 Bellmakers,
I Tinmen, .
[ Workers in Copper,

' Typefounders, .
Dyers,

Lacquerers (enamellers),
Painters and Colour )
Lead Dust -j Grinders, . J
Printers (including )
Compositors), . J
Lead-Mine and White )
'[ Lead workers, . j

Brass Dust Workers in Brass,

• Dr Ludwig Hirt, die Krankheiten der Arbiter, Beitriige.
1873-78— modified and adapted.

Are

Mean Duration

Consumptive.

of Life.

Do 0

62-9

54-0

12-5

1 9-9.

11-5

49-1

10-7

55-1

48-5

36-9

36-5

55-9

26-3

• 64-6

19-7

U-1

47-0

48-6

34-9

25-0

63-7

25-0

45-0

24-5

57-6

21-6

54-3

20-0

61-7

Leipzig,

APPENDIX.

TABLE II.
Mineral Dust.

In every 100 Patients
among

Are
Consumptive.

Mean Duration
of Life.

Grindstone-makers, ....

90-0

4-0

Flintcutters, . . . . )

80-0

Glass cutters and Polishers, . J

Stone-cutters (including Masons),

36-4

36-3

Workers in Glass, ....

35-0

42-5

Plasterers, . . . . .

19-0

Porcelain workers, . . • .

16-0

42-5

Potters, ......

14-7

53-1

Diamond workers, . . . .

9-0

Cement workers, ....

8-10

50-0

TABLE IIL
Vegetable Dust.

}

Cigar-makers (including Tobacco
workers), ....

Weavers,

Cotton, Flax, and Hemp Dressers,

Eopemakers, . . . . .

Joiners (including Cabinetmakers, )
Upholsterers, and Carpenters), /

Millers, ......

Bakers, ......

Chimney Sweeps, . . . .

Miners (Coal),

TABLE IV.
Animal Dust.

Brush-makers,
Hair-dressers,
Skinners,
Turners,
Hatters,
Button-makers,
Harness-makers,
Cloth-makers, .

36-9

25-0
60-0
18-9

14-6

10-9
7-0
6-5
0-8

49-1
32-1
23-2
16-2
15-5
15-0
12-8
10-0

55-0

51-7
44-0

44- 0

49-8

45- 1

45-3

57-9

50- 5
67-4

51- 6

APPENDIX.

TABLE V.
Animal Dust with Specific Poison.

In every 100 Patients
among

Wool-sorters, .
Eag-pickers,
Paper-makers, .

TABLE VI.

Gases and Volatile Ejla.nations.
Straw-hat makers.

Are Mean Duration.

Consumptive. of Life.

37-6

Jewellers,
Bleachers,
Soap-boilers,
Tanners and Curriers,
Charcoal-burners,
Parafine-makers,
Candle-makers,
Grinders of Oleaginous Grains,

9-3
9-3
2-0

530
58-0
61-3
61-3

62-0

TABLE VII.
No Dust,

Constrained Bodily Position, and Bad Ventilation.

Needle-women (of every class),
Tailors, ....
Shoe-makers,

Glovers, ....
Writers' Clerks,

190
19-0
18-7

10-0

Phosphorus
Mercury

Arsenical
Dust

TABLE VIIL

Dust from Poisonous Metals.

Workers in Phosphorus,
Workers in Quicksilver,
' Workers in Arsenic,
Arsenical Green Pigment-
j workers.
Workers in Arsenical Blue,
Artificial Flower-makers
in Arsenical Green,

25-0
11-0

25-0

36-0

44-0
47-4
47-0

APPENDIX.

TABLE IX.

Showing Diseases and Average Life among Farriers,
Cutlers, Lock- makers, and File-cutters.

In 100 Patients.

Consumption.

Chronic
Bronchitis.

Emphysema.

Pneumonia.

Acute
Maladies.

Digestive
Maladies.

Rheumatism.

Heart Diseases.

Average Dura-
tion of Life.

Farriers. . .

10-7

9-8

0-5

37-5

24-2

9-8

0-9

55-1

Cutlers . . .

12-2

3-7

3-2

35-3

27-1

6 3

2-0

Lock-makers .

11-5

9-2

2-6

5-8

38-2

19-4

10-3

491

File-cutters .

62-2

17-4

12-2

17-6

54-0

TABLE X.
Diseases among Workers in Wood.

In 100 Patients.

Consumption.

Chronic
Bronchitis.

Emphysema.

Pneumonia.

Acute
Maladies.

Digestive
Maladies.

Rheumatism.

Heart Diseases.

Average Dura-
tion of Life.

Joiners . . .

14-6

lo-i

3-9

6 0

34 0

18-4

10-4

2-9

49 -S

Carpenters

14-4

0-5

0-9

29-2

14-4

17-4

4-3

55-7

Wheelwriglits

12-5

0-2

1-3

5-2

11-6

18-7

9-2

1-3

... 1

TABLE XL

Eelative Frequency of Chest Disease from Animal Dust.

In 100 Patients.

Consumption.

Chronic
Bronchitis.

Emphysema.

Pneumonia.

Acute
Maladies.

Digestive
Maladies.

Rheumatism.

Heart Diseases.

Average Dura-
tion of Life.

Brush makers .

49-1

28-0

3 4

7-0

12-2

3-7

Hairdressers .

321

47-8

2-5

10-7

25-4

14-6

51-9

Saddlers . .

12-8

7-5

2-5

5-0

40-1

22-6

7-6

i-9

53-6

Upholsterers ,

25-9

11-7

2-7

10-3

24-9

27-7

4-0

Farriers . .

23-2

10-7

8-1 1

23-3

10-9

12-6

2-5

50-5

Hatters. , .

13-5

6-7

5-6 1

53-3

28-7

5-5

51-6

APPENDIX.

TABLE XII.

Relative Diseases among Tanners, Catgut-makers,
Butchers, and Soap-makers.

In 100 Patients.

mption.

onlc
cliitis.

ysema.

o
E

O DO

> <y

natism.

09
O

e Dura-
f Ufe.

0
o

Chr
Bron

mph

be OS

a)
.a

tc o

Tanners

9-2

7-4

31-9

12-9

16-8

61-2

Catgut-makers

60-2

Butchers . .

7"-9

e's

42-'2

17*6

1.3-3

6'-7

56-5

Soap-makers .

9-3

180

5-3

8-9

37-5

14-5

5-3

61-3

mun i- [I -ii'iia.r

1
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