November 5, 1915.

THE COLLIERY GUARDIAN.

927

working room. The apparatus is designed to rest on
the floor, but it may also be constructed for erection at
1 a higher level. In either
case it may be connected to
a fresh air duct coming down
through the roof or from the
upper portion of a building.

In connection with the
ventilation of underground
railways and tubes or sub-
ways, it is interesting and
instructive to consider the
advance that has been made
within the past 50 years, and
even during the past 20 or
even 10 years. In the first
underground railway in
London (the Metropolitan
and District Railway), the
original intention was to use

• hot water locomotives, and
no special provision was
made for ventilation at all.
However, from the first,
coal or coked fired steam
locomotives were used for _________________

traction, and hence the
ventilation of the tunnel	Fig.	7.

sections was bad from the

start. Within the past 10 years the old Metropolitan
and District Railway has been transformed into an
electrically-worked line, and is now probably the best
ventilated underground railway of its kind in existence.
This is owing to the fact that the tunnels, which are
of large dimensions, are only a few feet below street
level, whilst the stations are on an average about half
a mile apart, and most of them have been opened up
to the outside air with large open spaces on each side.

• Under these conditions, and with electrical traction, the
movement of the double-track trains travelling in oppo-
site directions keeps the air of the tunnels in sufficient
motion to prevent stagnation, or the existence of the
deleterious uniform or windless atmosphere so much
complained of by hygienic authorities, and so gives
good ventilation and a feeling of freshness all the year
round.

On the other hand, the London tube railways and the
undergrounds or subways of Paris and New York are
. generally unprovided with open stations or with spaces
or areas throughout the lines open to the outside air,
and, although electrically worked and otherwise well
equipped, cannot by any stretch of imagination be said
to be well ventilated. As regards ventilation, these
Paris and New York lines were designed to work on
practically the same principle as that originally applic-
able to the London tube lines, i.e., the “piston action”
of the trains when running was fallaciously expected to
be sufficient for the perfect ventilation of the tunnels.

Satisfactory ventilation can be secured either by
largely opening up these underground conduits at short
intervals completely to the open air, and depending upon
the working of the traffic electrically each way to give
the necessary movement to the atmosphere therein (as
exemplified in the case of the London Metropolitan), or
by flooding these underground roadways, when practi-
cally closed to the open air above, with fresh air in
sufficient volume from a central position in each section
towards exits at each end, by mechanical meani, sub-
stantially in the manner illustrated diagrammatically in

2 TRACK SUB WAY OR TUNNEL

2 TRACK SUB WAY OR TUNNEL

2 TRACK SUB WAY OR TUNNEL

RECESS FOR FRESH AIR

2TRACKSUB WAYORTUNNEL

Fig. 8.

fig. 8, which represents a longitudinal elevation (part
section) and a plan of a working model (1 in. to the
foot) of a two-track underground electric railway or
subway. A specially constructed open type of fan,
having double air inlets, each 7| in. in diameter (repre-
senting 7| ft. diameter air inlets in actual or full size)
is placed in a recess formed on the side of the subway,
so as to draw fresh air down the recess (from above or
the outside) and propel the air in volume into the side
and towards the upper part of the subway or tunnel.

In this model the motor and fan running at 4,000
revolutions per minute and the motor absorbing 1-6 horse
power, 1,004 cu. ft. of fresh air per minute are pro-
pelled along the tunnel towards each end of the section
(or towards each station) as shown by the arrows; the
air current being rated at an approximate air speed of
4’6 miles per hour towards each extremity E. These
figures indicate (giving the same rate of air speed or
current in an actual tunnel) for a fan of full size or
running speed of 330 revolutions per minute, and the
delivery of 150,000 cu. ft. of air per minute towards each
end of the tunnel, or for both ends E a total of 300,000
cu. ft. of air per minute, with an absorption of from
90 to 170 horse-power, according to the form of fan

used,* effecting a change of the whole of the cubical air
contents of the tunnel section every 3 to 3| minutes
between two stations half a mile apart.

The author has come to the conclusion that for “ sub-
way ” ventilation there is no necessity to do more than
bring the fresh air from a point outside to where it is
needed, this being sufficient to give atmospheric con-
ditions equal to those in wide, healthy streets or
roadways above ground. One great advantage of an
efficient system, such as the “ Plenum ” (a description
of which is also given in ’ connection with under-deck
ventilation on ships) is that, given a pure source from
which to obtain the fresh air supply, all local or
surrounding smells are effectively kept out of the apart-
ments or places treated, while the vitiated air is
thoroughly displaced through the proper exits. Of
course, where the external source is either impure or
not free from suspicion, or is dust laden or smoke con-
taminated, it may require to be screened or cleansed (as
in the case of the Singer engine room) before it is drawn
or propelled into buildings containing valuable and
delicate machinery, and where there are workers.

By no other methods than those on the lines described
and known to present-day ventilating science can we
obtain what has been called a “ sufficient draught of
cool and relatively dry air (conducive to good health),”
.free from unpleasant currents, in crowded places, and
especially in overheated engine rooms, subways, etc.;
but the results obtained by the author would, some years
ago, probably have been considered almost impossible!
and, with our present-day facilities for the economical
adoption and distribution of mechanical power by
electricity, there is no excuse for lack of good ventilation
anywhere.

* In actual practice, these full-size fans will develop con-
siderably more capacity for the horse-power stated, or will
absorb much less power while giving the volumes of air
mentioned.

INDUSTRIAL ACCIDENTS AND
DISEASES*

Examination of the Eye.

By Frank Shvfflebotham, M.A., M.D. (Cantab.)

I venture to think that never was there a time in the
history either of medicine, or of this country, when
it was more important to consider from a medical point of
view the amount of damage done to the workers by accident
and disease in the ordinary course of their employment.
Great Britain can never claim to have been organised, in
any sense of the term, from an industrial point of viiew;
but at the present time the needs of the country are such
that it has been found essential that the nation should
consider seriously the question of taking stocky so to speak,
of our industrial possibilities with a view to raising to the
highest possible standard the industrial efficiency of our
country. I do not think that sufficient attention has been
paid by the medical profession as a whole to the conditions
of employment in this country, at all events, by those
whom we have regarded as the leaders of the profession.

We are not dealing with a few people here or a few people
there, but with a very large percentage of the total workers
of this country, and in the coal mining industry we can
say that, on the average, in every six years, everybody
employed in the mines of this country is killed or injured.

Up to the present, the attention of medical men has been
concentrated rather upon the immediate treatment of those
who are injured, without much special reference to the
manner in which the accidents have been produced; but just
as in the field of public health, medical men have been
the pioneers of the greatest reforms, so I feel that in the
question of industrial 'accidents medical men will have to
consider, and will have to be consulted, as to the best
possible working conditions for the workers, and it will
therefore be necessary for them to be conversant with every
detail of the industry in which they are specially interested
or in which their special work lies.

Unfortunately, in past years, every advance that has been
made for the improvement of conditions in factories and
mines has always been met with the cry that the industry
was being ruined. I think that the main reason for this
course of events has been that innovations have been
introduced by the politician, and have never been sufficiently
backed by the medical prefession. In spite of all legislative
attempts, we should not fail to remember what a large
proportion of the working people of this country -are seriously
injured year by year, and it should be realised that the
number of accidents is on the increase, and not on the
decrease. It is our duty as medical men to endeavour to
lessen the incidence of these accidents, and when we are
directly dealing with those who have been unfortunate
enough to sustain injury, to recommend such treatment,
either in institutions or at home, that the injured man will
be able to return to the industrial ranks, fit and healthy, in
the shortest possible time.

Every medical man who practises in an industrial centre
knows the importance of the examination of the eye in
almost every serious case of industrial accident. In cases
of head injury, and injury to the spinal cord, it is most
essential that a complete examination of the eye be made in
every instance; if this examination is not carried out, the
conditions may be mistaken, wrong treatment prescribed,
with sometimes disastrous results, and a misleading
prognosis given. In cases of traumatic meningitis, of
cerebral compression, of cerebellar tumour, and in some cases
of fractured base of the skull, the examination of the eye
indicates the exact condition of the lesion that has been
set up by the accident. In speaking of examination of the
eye, I do not wish simply to refer to ophthalmoscopic
examination. The examination of the field of vision, of the
visual acuity, of the condition of the muscles of the eyeball
and the movements of the eyeball itself are all of equal
importance. Mr. B. Cridland has shown at a previous
congress, in cases of traumatic neurasthenia, how the field
of vision is contracted, not only for white, but for blue and
red, and I believe that in cases of traumatic neurasthenia
the examination of the field of vision has the greatest
diagnostic value. But the examination of the eye is of
the greatest importance in detecting concurrent disease,

* From an introduction to a discussion on industrial acci-
dents and diseases at the Oxford Ophthalmological Congress,
on duly 16, 1915.

which is entirely independent of the injuries which have
been produced by accidents, although in some cases the
disease may be aggravated by the injury.

The frequency of the pneumococcal ulcer of the cornea
among coal miners is a question which I would just like to
refer to for a few moments. As you may naturally expect,
the number of slight corneal abrasions occurring among coal
miners is extremely great in every colliery district, and
medical men practising in these districts know from their
experience that a large proportion of these slight injuries are
the beginning of prolonged ulceration of the cornea due to
infection by the pneumococcus. I bring this subject before
the notice of the Congress, not because I do not believe a
single member is not perfectly familiar with this point, but
I would like medical practitioners in colliery districts to pav
special attention to the condition of the lachrymal sac in all
cases of slight injury to the.eye, and also in cases of con-
junctivitis. Dr. Webster, of Newcastle-under-Lyme, tells
me that in the North Staffordshire district he has literally
come across scores of cases of pneumococcal infection of the
lachrymal sac causing the most prolonged and serious corneal
ulceration, and it is essential that treatment of the lachrymal
sac has got to occupy in the future a very much more impor-
tant position in the general hygiene of the worker than it
has done in the past, so as to safeguard the miner from the
effects of the slight accidents to which I have already referred.
In cases of operation for cataract among coal miners, some
surgeons believe it necessary to dissect out the lacrymal sac
in cases of infection, as a preliminary operation.

Industrial diseases have occupied more attention on the
part of medical men than the after-effects of accidents, with
the result that we have to deal with a very much smaller
number of cases.

In the chemical industries, eye affections may arise from
poisoning by the nitro-benzine products, . by carbon
bisulphide, by nickel carbonyl, as well as by nitrous fumes,
and in processes in which salts of chromium are used one
may find ulceration of the cornea, conjunctivitis, inflamma-
tion, and sometimes ulceration of the eyelids,, while pitch
and tarry compounds are known to produce epitheliomatous
ulceration of the corneal surface of the eye.

But the most frequent of all industrial diseases is miners*
nystagmus. It is generally admitted that the miners who
have contracted miners* nystagmus are amongst the most
skilled and the most industrious of their .class, and from
the point of view of industrial efficiency, it is a great loss to
this country that the men should be so incapacitated.

We do not know the actual cause of miners’ nystagmus,
but we do know what the principal effects are in the causa-
tion of this disease, and as long as the illumination of the
mine is so defective, we must try in other wavs to reduce the
incidence of this disease. It has been pointed out at this
Congress in previous y^ars, as well as the Royal Society of
Medicine and in other places, that some refractive error or
some error in the refracting media is present in a large pro-
portion of the cases of miners’ nystagmus. Different
observers give a different percentage, but all of them agree
that it. is sufficiently high. If a refractive error is such a
striking factor in the production of miners* nystagmus, then
surely men who are suffering from astigmatism and hvper-
metropia, opacity of the lens, and other like disabilities,
should be prevented from working in the mines in the first
instance. In the ordinary course of life, if a boy be
deformed in his limbs or hands or feet, then from the very
outset suitable employment is found for him, and it seems
strange that when there are deformities, if I may use that
word, of the eye, suitable work should not be found for him
in callings in life other than mining. I believe that before a
boy or a man be allowed to work in a mine, he should have
his eyes examined, and, if they are at fault, then he should
be prevented from working in the mine, not only because
he would be predisposed to nystagmus, but a man with defec-
tive sight must be a danger to his fellow workmen in such a
dangerous occupation as that of mining. If this proposition
be not admitted, then it may be said that a man is being
directly encouraged to acquire a disease from which he may
suffer more or less all his life, and he will be the very reverse
of what is known as industrially efficient.

One case that has come under my notice lately will illus-
trate this point. A young man, 22 years of age, was certified
as affected with miners’ nystagmus in the middle of May of
this year. I saw the man five weeks afterwards, when he
complained of headaches, and he had an old squint, but I was
able to detect any oscillation of the eyeballs on that day. Mr.
S. McMurray examined him, and found that he was suffer-
ing from marked long sight and astigmatism, besides having
an old squint of 25 degs., which had been caused by neglected
long sight. This squint rendered the man practically- a one-
eyed man. It seems to me that this man should never have
been allowed to work in the pit; he should have had spectacles
at an early age, and had he been examined prior to ^working
in the pit, his eye trouble would have been found out, glasses
would have been prescribed for him, and he would have found
suitable work in other directions, since it is impossible for
miners to wear glasses at work.

In conclusion, I feel that in dealing with questions of
industrial accidents and industrial diseases, it is essential for
medical men in every case to make a complete examination of
the injured workman, and to obtain a report upon the exact
condition of the eye. The eye may be said to be the gateway
of the brain, but its condition very often indicates some
general disease from which the man may be affected after
having completely recovered from the effects of the accident or
the occupational disease from which he had been previously a
sufferer. In this way, in many cases, it may be regarded as
the periscope to the whole human frame.

If accidents are to be prevented, and the incidence of
disease lessened in the industries of this country, let me say
again that it is essential that medical men should be con-
versant with all the details of these industries, so that they
can be the pioneers of reform in this direction.

Mr. Arthur Cecil Wade, of the firm of W. "Wade and Son,
Plymouth, has been appointed a lieutenant in the Army
Ordnance Department, and stationed at Portsmouth.

The President of Peru has approved the Bill dealing with
the export of minerals and metals from that country.
Article 1 of the Bill provides that from Monday next, the
exportation of minerals and mining products of all classes
will pay a duty of 3 per cent, ad valorem if proceeding from
the mining regions served by the Central and Southern
railways of Peru, and 2 per cent, if proceeding from other
mineral regions. Article 2 provides that from the same
date a duty of 2s. per ton will be charged on the production
of petroleum.