‘ 
some, to him, new view of sanitary matters ; this is very mis- 
chievous. A man may do more harm by giving the weight of 
his authority to erroneous views respecting the method to be 
employed for the prevention of diseases than he has done good 
during the whole of his life in any other way. None but those 
who have made a special study of this subject have a right to 
* speak on it, or at any rate have a right to influence the public 
mind with regard to it. The amount of good which may be 
done by the exposition of correct views on sanitary matters is 
incalculable ; the amount of evil done by the enunciation of 
erroneous views, backed by apparent authority, fearful. 
But if sanitary science is a thing of yesterday, such is not the 
case with the observation of sanitary facts, nor with the practice 
of sanitary art ; and, while it is true that sanitary science is essen- 
tially and entirely a medical study, and is necessarily so, it is 
equally true that the practice of the art of preserving the health 
is not only possible to all, but is a duty which devolves upon all. 
In all ages we have had writers on this subject. From all 
countries we may learn useful lessons about it. From the times 
of Hippocrates, Galen, and Celsus, we have had records of the 
results of observations on the methods of preserving the health ; 
from the time of Moses we have had lawgivers imposing salu- 
tary conditions of existence upon unwilling, because ignorant 
populations. We look upon the immense engineering works 
undertaken and carried out by the Romans to supply their towns 
with pure water with astonishment, when we turn round and see 
our own towns supplied from polluted rivers, or, worse still, from 
shallow wells dug in the soil upon which they themselves stand, 
wells supplied in most cases chiefly by the foul water which has 
percolated from the surface of the ground. We have found out in 
later times that one of the main conditions of the health of com- 
munities depends on the purity of the drinking water, and we see 
that the Roman engineers, by having to go to a considerable dis- 
tance for water in order to get it toa sufficient height in their 
cities, accidentally, as it were, fulfilled one of the most important 
of sanitary requirements. 
“Knowledge is power,” and as we come” to know more of 
the conditions which favour the spread of diseases, as we do 
daily, it is our own fault if we neglect to use the power which 
that knowledge gives us. There are two conditions of insa- 
lubrity which are pre-eminent. I hardly know which to place 
first. The one is overcrowding, and the other the accumulation 
of refuse matters in and about dwellings. These conditions 
were those which especially favoured the spread of the fearful 
plagues of the middle ages ; as a result of over-crowding we 
have a deteriorated condition of the air, from the diminution of 
the amount of its most essential constituent, oxygen ; and, worse 
still, we have it rendered foul by the exhalation of decomposing 
organic matters from the bodies of the persons breathing it. 
Such a state of air is especially favourable to the multiplication 
of the poisons of diseases ; such a state of the air is also brought 
about by the non-removal of refuse matters from the vicinity of 
habitations. Dr. Laycock tells us that the plague in York in 
each of its visitations, and also the cholera, broke out in the 
same abominably filthy place ; and in cholera epidemics it has 
been repeatedly noticed that those parts of towns which are 
most filthy and most over-crowded, always suffer worst. 
But the danger is not only from special epidemic diseases, 
Such insanitary conditions induce a lowered vitality of the in- 
habitants, who become prone to attacks of diseases of all sorts; 
and then we have sickness, inability to work, and consequent 
inability to earn bread and to pay rents, and so the evil recoils 
from the tenants upon the landlords. One witness says, “ Rent 
is the best got from healthy houses.” Another, “ Sickness at 
all times forms an excuse for the poorer part not paying their 
rent, and a reasonable excuse.” 
1 consider that one of the most important conclusions that the 
study of sanitary science has forced upon us lately is the conclu- 
sion that the immediate removal of, refuse matters is one of the 
first necessities of the healthy existence of a community. There 
are those who would have you believe that refuse matters may 
be rendered innocuous in one way or another, so that they 
may be kept with safety in and near to houses. Don’t listen 
to them; the principle is wrong—radically wrong. Depend 
upon it that the true method is to get rid of such matters at 
once, and in the simplest possible way, and that is the cheapest 
plan in the end. Show me a town where refuse matters are 
kept—no matter how they are treated—and I will show you a 
town where the standard of vitality is low ; I will show you a 
town with a high death-rate, especially among children. 
NATURE 
| excellent position of London, it is 
To take the other side of the question, look at London. q 
There you have a population of 3} millions, with the lowest 
death-rate of any very large collected population in the world, — 
with one of the lowest death-rates among the large towns of even 
our own country. Why is this? I say unhesitatingly, and with- 
out fear of contradiction, that with all allowances made for the 
ainly due to the fact that the 
principle there, however incompletely it may be carried out, is 
the immediate removal of all refuse matters; in London, the 
water-carriage system, by which the foul water containing a very 
large proportion of the refuse matters of the population, is re- 
moved by gravitation in sewers, is carried out far more perfectly 
than in any other large town, and this system is daily being ren- 
dered more perfect there ; it is the right system based upona 
true principle, and its results are most salutary. When you have 
got rid of refuse matters, then see what you can do with them ; 
and here arises a very curious consideration. Sewers, in most 
instances, were not originally built as sewers, but as drains; a 
sewer is a conduit for the removal of fouled water; a drain is a 
channel for the removal of mere superfluous water, the object 
being to dry the soil. The pattern of all our old sewers, the 
Cloaca Maxima at Rome, was originally a drain ; it was con- 
structed by Tarquinius Priscus, the fifth King of Rome, 600, 
years B.C., to drain the marshy ground between the Palatine 
and Capitoline hills, and it was so well constructed that it drains 
that ground at this moment. Pliny wondered that it had en-_ 
dured 700 years unaffected by earthquakes, by inundations of the 
Tiber, by masses which had rolled into its channel, and by the — 
weight of the ruins which had fallen over it. What would he 
say could he see it now, as any of you may who choose to go to 
Rome, still discharging, after more than 2,400 years, its dirty 
water into the Tiber? But the convenience of the great drain’ 
for the disposal of refuse matters soon became apparent, and so 
it was turned into a sewer, and has been one ever since. 
Well, what are we to do with the refuse sewer water, when we _ 
have got it out of our towns? This is one of the greatest ques- 
tions of the day. Drains, of course, were naturally made to 
discharge into rivers, their proper place, so Jong as they were 
only drains ; but when they come to be used as sewers, this will 
not do; in the first place the rivers are fouled, and in the next 
the manure is lost. TI shall be able to show you in the course of 
the lecture that the only way known by which sewer water can be 
either purified or utilised, is by turning it, with suitable precau- 
tions, on to land, that this may be done, not only without 
injury to the health of the neighburhood, but with great benefit 
in many ways. 
We have spoken of drains to dry the soil ; what is the necessity 
of this? Every farmer knows that crops will not flourish on un-_ 
drained land ; neither can human beings ; a damp house is a 
synonym for an unhealthy house, you all know that ; but it is” 
only within the last few years, as the result of a most important 
sanitary research, made by Dr. Buchanan, that we have come to 
know as a scientific fact, beyond all dispute, that the drying of — 
the soil of a town reduces the number of deaths from consump- 
tion in a most extraordinary manner ; in some towns the number 
of deaths under this head has been reduced by one-third or even 
by one-half, in this way. 
To mention some other special diseases which have been suc: 
cessfully combatted of late years, look at scurvy, that terrible 
malady which formerly decimated our navies! We know now _ 
that that disease may be prevented by the use of limejuice as 
part of the daily food, and we are no longer afraid of it. (Some > 
illustrations of the ravages of this disease were given. ) ‘ 
Look at small-pox, beyond all exception the most fearful 
epidemic disease with which the world was ever afflicted! We 
know how to prevent it, and we have recently had a v : 
lesson from not applying that knowledge. It is to the inpeeae 
credit of England that Jenner, the discoverer of vaccination, was — 
an Englishman ; there are certain people, and they have actually — 
formed a society, who are trying to get compulsory vaccination 
done away with in this country. Let me tell you that if there is 
one fact established in preventive medicine it is that vaccination | 
affords a protection from small-pox ; let me tell you that this © 
statement is founded upon an induction such as has been brought to 
bear upon no other subject in medical science; and, let me add, 
that those persons who bring isolated facts as arguments against 
a statement so supported, show that they have no idea of the 
nature of an inductive argument at all. An unvaccinated per- 
son is a danger to the community, and ought not to be allowed 
to go at large, and so far from persons being merely fined for 
