[Reprinted from the Journal of the Franklin Institute, January, 1881.] 
ON THE WHOLESOMENESS OF DRINKING WW&R. 
By Reuben Haines. 1/ 
Abstract of a Lecture delivered before the Franklin Institute, December 9th, 1880. 
It was only about thirty years ago that cholera epidemics were dis- 
covered to be largely due to the transmission of the disease from one 
person to another by means of water used for drinking. This disease 
is unquestionably transmitted also in other ways, as for example, by 
the atmosphere; but that water is one of them, and in some countries 
the most important one, the vital statistics of England prove beyond 
a doubt. I say, in some countries, not in all; for it appears that the 
evidence in Germany, which seems to have been very thoroughly inves- 
tigated, is against the theory of the carriage by water of the 
cholera poison in such a way as to cause infection. Pettenkofer, the 
celebrated sanitary authority of Germany, is entirely opposed to this 
view. Nevertheless, in England, India, Holland, and a few localities 
in Germany, the evidence appears overwhelming. Dr. Parkes states 
that while we should give proper deference to the evidence in Germany 
and Austria, we should not allow it to outweigh the evidence from 
other countries. 
It has also been found that typhoid fever has been spread through 
towns and smaller communities and through separate households by 
carriage of the infection by drinking-water. So many instances of this 
have become known that it may be considered proved beyond all pos- 
sible doubt to be a fact, and one which is generally and not merely 
exceptionally true. 
It is true, however, that typhoid fever, like cholera, may be trans- 
mitted also by the air; and there can be no question that the gases or 
vapors emanating from sewers and drains and breathed in a confined 
atmosphere are a very frequent means of transmitting the disease. 
Dr. Parkes states, in the latest edition of his work, that the ques- 
tion which is the most important or frequent means of infection, air or 
water, cannot vet be answered. Dysentery has been long known to be 
caused partly by bad water. There is considerable evidence to show 
that water may transmit diphtheria, but not sufficient to prove it with 2 
certainty, except perphaps some evidence in Massachusetts which is- 
very strong. 
When the water in any of these cases lias been examined by chemi- 
cal tests it has generally been found to have organic matter either 
dissolved up in it or suspended in it. Frequently this material has been 
found so entirely dissolved as not to be detected by the eye; that is to 
sav, water which was clear, colorless, free from anything visible, except 
a very few floating particles and which even had a good, refreshing 
taste, was found on careful examination of all the circumstances to be 
without the slightest doubt the real cause of the spread of typhoid 
fever and cholera from one person to another. 
Water, on the other hand, which is pure or free from any contami- 
nation with human sewage, in any part of its history in past or present 
time, has never been proved to be the means of infection with such 
diseases as cholera and typhoid fever. But diseases of other sorts 
have been caused by mineral matters dissolved in the water or by 
vegetable matter held in suspension, while the water was nevertheless- 
entirely free from sewage contamination. 
Water, then, which is impure, is to be dreaded as a frequent cause of 
disease. But in what does this impurity consist and how are we to- 
distinguish the two sorts of impurity I have mentioned? We will 
understand this better if we first carefully consider what constitutes a 
naturally pure water and which is found, by wide experience, to be 
perfectly wholesome and should be our daily drink. 
Those who have studied chemistry are aware that absolutely pure 
water is composed of one part by weight of hydrogen to eight parts 
by weight of oxygen, or, by volume, of two parts of the former to 
one part of the latter. Chemically pure water contains nothing else 
whatever. But such water does not exist in nature, nor can it proba- 
bly be produced in the chemical laboratory, for the purest distilled 
water, redistilled many times, is found, perhaps invariably, to contain 
exceedingly minute traces of ammonia and on standing a few hours it 
absorbs oxygen and nitrogen from the air to which it is exposed. 
When, therefore, we speak of a pure, wholesome water we do not 
mean water which is chemically pure, but one which is as free from 
foreign substances as is to be found under the most favorable natural 
conditions. 
We should consider all natural water found either on or below the 
surface of the ground as having been originally precipitated out of the 3 
atmosphere in the form of rain, snow, hail, fog or dew. Of these, 
rain and snow are obviously the most important, and these in falling 
carry down with them a part of whatever may be either naturally or 
abnormally present in the atmosphere. Now, we know by practical 
experience that the atmosphere in high situations is generally purer 
than on level plains or in low places. When onr bodies are in need 
of an invigorating atmosphere we go to the mountains, and those who 
have traveled in mountainous regions often speak of the delightful 
effects experienced, provided they do not enter too rare an atmosphere. 
Chemical analysis confirms this impression. The atmosphere of the 
mountain is generally really purer than that of the valley at its foot. 
Rain collected near the surface of the earth will, therefore, be more 
impure than that collected at a considerable height, because of the 
greater impurity of the air near the surface of the ground. After the 
elapse of a short time the rain water will be much purer than dur- 
ing the first part of the time of rainfall. 
The purest air of the mountain regions contains, besides nitrogen 
and oxygen, a small proportion of carbonic acid in the free state and 
still smaller amounts of ammonia combined with carbonic acid, nitric 
acid and nitrous acid. Besides these, there is found also a very small 
amount of organic matter suspended in the air, probably dead or effete 
matter swept up by currents from living animals and from vegetation 
in decay. The amount of this organic dust becomes less and less as 
we ascend to greater heights, while the proportion of carbonic acid 
becomes somewhat increased. All of these various gaseous and solid 
substances are therefore to be found in rain water. Since a part of 
the rain goes to form springs, we find these substances in the purest 
spring-waters; but here they exist in a somewhat different form from 
that which they had in rain. Water in passing through the ground 
always comes in contact with some substances capable of dissolving 
more or less in it. 
Water in its purest state may be said to be an almost universal sol- 
vent. Give it sufficient time and the proper temperature and atmos- 
pheric pressure and it will dissolve an appreciable amount of the most 
insoluble substances. This effect will take place much more readilv 
when the water contains certain saline substances, especially nitrates 
and chlorides. When rain water has carried down from the atmos- 
phere salts of ammonia, even if in very minute amounts, its solvent 
power on soil and rock is thereby increased, and this increase will be 4 
in some proportion to the amount of impurity washed out of the 
atmosphere. 
The soil itself is known to contain carbonic acid in its pores in 
much larger proportion to the other gases than exists in the atmos- 
phere. Carbonic acid, we all know, is soluble in water in greater 
amount, according to the pressure, as is well shown in the soda-water 
fountain. This gas when dissolved in water has a great solvent power 
on limestone rock, and when the carbonic acid gas escapes again by 
evaporation the water leaves those beautiful pendant stony icicles 
which we find in limestone caves like the Mammoth Cave of Ken- 
tucky and which we see on a very small scale on the arched roof of 
many stone bridges, where they are formed from the mortar between 
the stones of the arch. In fact, the caves themselves are thought to 
be formed by this solvent action. Lime is a part of the material of 
many other kinds of rocks beside limestone and of the soil resulting 
from their disintegration. The gaseous carbonic acid of the soil added 
to that already in the rain and to the nitrous and nitric acids in com- 
bination with ammonia also found in it, dissolve a part of the lime 
and other mineral matter of the soil and rock, and when this soluble 
mineral matter is in large amount a mineral spring is formed thereby 
or simply an ordinary limestone spring, as the case may be. In either 
case the water is called “ hard.” If the rock is of insoluble material 
like granite or gneiss, only a very small part of it is dissolved, and in 
this case a soft spring water is formed. Yet even in granitic regions 
the water may be hard, owing to such substances as sulphate of lime 
in the soil above the rock being dissolved in it. This is to a certain 
extent the case in Germantown, where some of the uncontaminated 
wells furnish quite a hard water while others give very soft water. 
All soils contain more or less organic matter derived from vegetable 
and animal matter in decay. Some of this will necessarily go into 
solution and pass into the spring water; but it appears that some 
spring waters contain less organic matter than the rain from which 
they are derived, so that there is possibly a filtering action going on in 
the soil in these cases. In the majority of cases, however, it is proba- 
ble and in many cases, it is certain, that a proportion of the organic 
material of the soil is added to that already in the rain. The amount 
of organic matter in soil and rock varies according to its geological 
nature. Thus, such rocks as the granitic series contain almost no organic 
matter, while sands and gravels, sometimes thought very free from it, 5 
generally contain considerable amounts of it, and occasionally in so 
large amounts as to cause the well waters to be decidedly injurious. 
I)r. Parkes mentions ;is an instance of this the district in the South 
of France called the “Landes,” where the sandy soil contains so much 
as to cause water of that region to produce malarial fever. 
Alluvial soil, or that deposited by the floods of rivers and streams, 
contains very frequently large amounts of organic matter which passes 
into springs and wells and renders them unwholesome. 
Waters from marshes are well known to contain large amounts of 
vegetable organic matter, so as often to prove extremely unwholesome. 
The case of the ship Argo, sailing in 1834 from Algiers to Marseilles, 
may be mentioned as a very strong instance in proof of this. 
Water coming from peat bogs is often highly colored with dissolved 
peaty matter. This peaty matter appears to be very different from the 
vegetable matter found in marsh water in not being in a state of actual 
decomposition, but being material which has in the solid state become 
partially carbonized and undergone thereby a change preparatory to 
becoming coal. Hence a number of chemists and sanitary officers 
have of late years strongly protested against the condemnation of peaty 
waters on the same grounds as marsh waters, declaring this to be a 
great mistake. It must be admitted by every candid student of this 
subject that some waters, which experience has proved to be very 
wholesome, originate in peat bogs and contain in the state used for 
drinking very considerable amounts of nitrogenous organic matter in 
solution, and there is evidence to show that this material is mainly of 
vegetable origin. 
Let us now consider the effects produced on the health by the mine- 
ral matter commonly present in ordinary spring and river waters under 
entirely natural conditions. While we can positively say that our 
present knowledge does not warrant the assertion that anv one of a 
number of these mineral substances have any injurious influence upon 
the health, it is nevertheless obviously true that a large excess of lime 
and magnesium salts, such as carbonates, sulphates and chlorides, are 
undoubtedly unwholesome in many instances. 
Waters which contain these salts of lime and magnesia are called 
“ hard” in consequence of their action on soap. The great waste of 
soaj) caused by these waters as well as their injurious influence in 
the boiling of meats and vegetables are matters of considerable im- 
portance in domestic economy. The soap waste and the tendency to 6 
form incrustations in boilers are facts of vast importance to the manu- 
facturer, but these considerations we will postpone for the present. 
While dyspepsia and other internal maladies have undoubtedly been 
traced to the drinking of water containing large amounts of these salts 
and while goitre and cretinism occur in close connection with, and some 
affirm, are caused by magnesian limestone waters, there seems to be 
still a decided disagreement among sanitary authorities as to the 
wholesomeness of a moderately hard water. Hardness, however, 
which is due chiefly to sulphate of magnesia, would seem certainly 
undesirable on several accounts. 
From these circumstances it will appear evident that the purest 
water naturally contains some appreciable amounts of mineral matter, 
and a water which does not contain it in too large amount, the limit of 
which has not been satisfactorily settled, may correctly be considered, 
so far as this is concerned, a perfectly pure water from a strictly sani- 
tary point of view. 
Finally, from this whole discussion it is clearly seen that a hygieni- 
•cally pure water must be defined as one which may contain naturally 
foreign substances, both mineral and organic, in small amounts; but 
if the organic matter is in larger amounts it must not be in a state of 
decay or decomposition or capable of readily undergoing such changes. 
Further consideration will lead us to modify this statement in so far 
as to add, that a pure water must also contain nothing which would 
leave a suspicion upon the mind of a probable present or future con- 
tamination with sewage. 
Some authorities would add that it also must contain no evidence of 
contamination with sewage in any past time. This is the position 
which Dr. Edward Frankland takes; but I think we may reasonably 
dissent from so severe a decision, which would exclude all our river 
waters as too dangerous for public supply. The chief reason for dis- 
senting is that the premises upon which he founds his conclusions 
have not been clearly proven, indeed, they are directly disputed by 
other chemists. 
We have heretofore considered water as it exists under wholly natu- 
ral conditions. We will now consider it as these conditions are influ- 
enced by man’s occupations and habits which are consequences or 
accompaniments of civilized life, and interpose circumstances more or 
less artificial. 
We have noticed the influence which the natural atmosphere has on 7 
the chemical condition of rain water. What is now the effect of the 
.atmosphere surrounding communities of men ? 
The atmosphere of cities and towns is rendered impure by the gases, 
smoke and soot issuing from the chimneys of houses and factories; by 
the dust from the streets, which is to a great extent organic; by par- 
ticles of all sorts of clothing, hair, skin and refuse material from every 
trade; organic matter from the breath and persons of men and ani- 
mals; and also by the gases resulting from decomposition of organic 
matter such as garbage and filth usually left for some time in places 
where it should not be at all, and the gases arising from stagnant 
sewers. 
Rain, in falling through such an atmosphere, will wash down these 
gases and organic dust, thereby rendering the atmosphere more fit to 
•dwell in. But the rain water itself will be exceedingly impure, and, 
indeed, so foul as to be entirely undrinkable without nausea. Beside 
the organic matter, nitric, sulphuric and muriatic acids, in the free 
state as well as combined, are found in such rain in considerable 
amount, which will vary greatly. In addition to the effete or dead 
organic matter we find alsb in the air minute forms of animal and 
vegetable life. Nevertheless, the air of well ventilated streets, even 
in large cities, is much purer than we might expect. The percentage 
of oxygen in many streets in the less crowded parts of London, that 
is to say, outside of the limits of old London, was found very slightly 
less, and the percentage of carbonic acid very slightly greater, than 
the natural amount on open land. 
Rain falling in suburban towns will, of course, be much purer than 
that of cities; but where the houses are situated near much-traveled 
streets, dust composed largely of organic matter will be deposited on 
the roof, and the rain water collected from this will contain consider- 
able impurity. 
If the gutters and pipes placed to carry the water into cisterns, or 
the cisterns themselves, are made of lead or zinc, these metals will be 
dissolved by the water so as to render the cistern water poisonous to 
drink. This corroding action is commonly much more rapid with 
rain water than with ordinary spring water. 
If we pass on to the consideration of other kinds of drinking 
water, we find that streams, ponds and rivers, all of which are used 
for this purpose, contain the dissolved manure from cultivated fields, 
and the filthy and often very poisonous drainage from factories of 8 
various kinds, besides those which make use of chemicals in their pro- 
cesses of manufacture. In addition to these, a most important source 
of impurity, and wherein lies probably by far the greatest danger, is 
the sewage of cities and towns situated along the banks of rivers or 
lakes used for drinking water, or on streams draining into them. Fre- 
quent reference is made to the solid impurities, such as wool factory 
refuse, floating on the surface, but any one who is acquainted with the 
methods used for cleansing the raw wool knows the disgusting charac- 
ter of the materials used for this purpose, enormous volumes of which 
are poured into the river after the operation is finished, and which are 
probably entirely unseen because dissolved in the water. It may be 
said, however, that much of this organic stuff may be entirely decom- 
posed and destroyed before it passes through the water mains and is 
delivered to consumers. We hear frequent remarks made on the 
impropriety and danger of allowing cemeteries of large extent, like- 
Laurel Hill, to drain into a river water used for drinking. The dan- 
gers arising from this source may, however, be said to be infinitesimal 
as compared with the direct drainage of human bowel excreta into the 
river by means of city sewers. The peculiar dangers of sewage con- 
tamination of public water supplies will be more clearly understood as. 
we discuss the subject in subsequent lectures of this course. 
Wells are the chief source of drinking water in country and subur- 
ban districts, and in towns having no public water supply. Artesian 
wells of great depth are sometimes used for city supply, but these 
are found unsatisfactory, because they do not meet the demands of an 
increasing population, and at the same time generally furnish a very 
hard water. 
Deep wells, or those over 100 feet in depth, but not artesian, are- 
seldom used for private domestic purposes, yet these are strongly advo- 
cated by high sanitary authorities, as furnishing the best supply for 
domestic use where a “ driven ” tube well cannot be sunk. The chief 
object is to go below and to exclude carefully the water in the upper 
water-bearing strata, which will be very liable to become impure. 
The wells generally used are less than fifty feet deep, and very fre- 
quently both these wells and the vaults and sinks for sewage are gen- 
erally placed tolerably near the house, and also near each other. Often 
in small lots, and sometimes in larger ones, the cesspools or privies and 
wells are not more than ten feet apart. Ash and garbage heaps, in a state 
of foetid decomposition, are frequently placed quite close to the well. All 9 
this has been found actually true in various parts of England, and in 
Massachusetts. 
As might be expected, numerous cases of typhoid fever were the 
immediate cause of the investigations that were made. Not only in 
Massachusetts is such culpable negligence to be found, but also in 
many other parts of this country, and as near home as the immediate 
neighborhood of Philadelphia. The recent investigations of the Mas- 
sachusetts State Board of Health into the sanitary condition of hotels 
and boarding-houses at various summer resorts of that State has 
brought to light a large number of cases of most astonishing ignorance 
and criminal negligence in this respect on the part of both hotel pro- 
prietors and smaller householders. Some of the cases discovered on 
the island of Martha’s Vineyard were so bad that it is difficult indeed 
to believe that any person would knowingly subject himself to such 
dangerous surroundings. 
Dr. Joseph G. Pinkham, in his very able and thorough official 
report, in 1876, on the sanitary condition of Lynn, Mass., himself a 
resident of that town, makes the following remarks: 
“ The most erroneous ideas in regard to the liability of wells to 
contamination prevail among the people. Those who are familiar 
with the principles of under-drainage by means of porous earthen tiles 
know that when they are placed in the earth the water will find its 
way, for quite a long distance on either side to them and through their 
pores; yet they are only small vacant spaces in the earth, while a well 
is a large and deep one, attracting moisture from a much greater dis- 
tance. But, notwithstanding these well known facts, persons of high 
intelligence on most points feel perfectly secure in regard to their wells 
with a cesspool or privy within a few feet of them.” 
In regard to other sanitary conditions, Dr. Pinkham remarks: 
“ Less than one-tenth part of the families, shops, etc., supplied with 
the city water have drains connecting with the sewers.” 
He estimates that drainage water to the amount of 420,000,000 
gallons are annually absorbed by the soil of this town, and then he 
asks the reader to form his own opinion as to the probability of this 
foul drainage soaking into the thousands of wells situated in this same 
thickly settled part of the town. There is but one possible answer to 
the question. It is but right to add that what was true of this town 
in 1876 may be very much improved now, but of this I have seen no 
positive statement. 10 
We know very well that any hole or ditch acts as a drain to the 
earth surrounding it. A well, as ordinarily constructed, is precisely 
such a hole for drainage. Any contaminating liquid, or any solid 
matter capable of being dissolved and washed into the soil by the 
rain; any such material as human sewage placed or allowed to flow 
on the surface of the ground near the well, will be exceedingly liable 
to pass directly into the well water. In other words, it will help feed 
that well, and a considerable amount of sewage escaping filtration will 
eventually be daily consumed by the people of the house in their 
drinking water. 
This is certainly not a pleasant subject to contemplate, but it will 
do us no possible good to shut our eyes to a state of things which act- 
ually exists, and which is every day liable to cause disease and death 
in our families. 
The more loose the soil in which the well is dug, that is to say, 
the more sandy and gravelly it is, the more liable the well is to con- 
tamination. It has been stated by some writers that a well drains a 
mass of soil in the shape of an inverted cone whose apex is the bottom 
of the well and whose base is an area of surface having a diameter 
equal to three times the depth of the well. That is, a well of 20 feet 
deep will drain an area 60 feet in diameter or any liquid within 30 
feet of the well will be liable to pass directly into it. This statement 
is necessarily a very rough estimate, since the area of surface drained 
will vary exceedingly according to the character of the soil. There is 
clear and positive evidence to show that in sandy and gravelly soils 
the extent of drainage area is far greater, even when the surface of 
the ground is level and the stratification of soil is quite horizontal. 
In New England the Massachusetts State Board of Health Reports give 
a number of instances where pollution of wells from cesspools situated 
in sandy level soil to the distance of more than 100 feet from the 
wells. The water was found by chemical analysis to be polluted with 
sewage and cases of typhoid fever occurred from the use of such water 
for drinking. 
If contamination takes place in level soil to the distance of 100 feet 
it will undoubtedly be liable to occur at much greater distances when 
the soil and rock are inclined towards the well. Mr. Child, Officer of 
Health for Oxfordshire, England, gives in one of his reports an 
instance of t[ie fouling of wells by petroleum or benzine which passed 
through the soil from a broken barrel buried in the ground to a num- 11 
ber of wells all of which were from 250 to 300 yards distant. The 
surface of the ground had a descent of about 60 feet between the two 
points toward the wells. About 82 people living in 15 houses were 
unable to use these wells for ten days and cattle refused to drink from 
one of them. In commenting on this remarkable case we should 
recollect the extraordinary penetrating power of petroleum oils. We 
can scarcely believe that sewage can be carried through nearly the sixth 
of a mile of soil as the petroleum was in this case. Nevertheless it 
furnishes a very good text for a sermon on the possibilities of sewage 
•contamination. 
Sand and gravel at first undoubtedly exert a certain amount of 
filtering power. But this is soon exhausted by the soil becoming 
saturated with filth, and in course of time a direct channel may be 
opened to the well through which the sewage may sometimes pass 
unobstructed even in the solid condition. 
From these facts we can positively say that a sandy and gravelly 
subsoil is one of the most dangerous of all situations for a shallow well 
in a thickly settled neighborhood, or where the cesspools and privies 
are not placed at the distance of several hundred feet from the well. 
A “tube” well, or “driven” well, will be little, if any, better what- 
ever, unless the tube is sunk to a depth approaching one hundred 
feet, except in a few cases. 
In addition to this we have already seen that such soils very often 
contain large amounts of organic matter, naturally present, and that 
this amount may be of itself so large as to produce malarial fever, by 
drinking the water. These considerations are of especial importance 
in regard to the well waters of southern and central New Jersey, and 
in regard to the possibilities of obtaining a really and permanently 
pure water supply, public or private, at the seaside resorts of that 
State, which must be considered by the sanitarian to be decidedly 
a doubtful matter, until careful chemical investigation can prove the 
contrary to be true. 
It has lately been discovered in Massachusetts that some kinds of 
rock are no real hindrance to the direct percolation of cesspool sewage 
through them. In one case the well was sunk down into the solid rock 
for some distance, and the walls of the well were with the utmost care 
laid in mortar and coated with hydraulic cement from the surface of 
the ground down to the rock. Yet with all this care contamination 
took place from a cesspool on the opposite side of the house and fifty 12 
feet distant from the well. The sewage was shown to have passed 
down through the rock at right angles to the dip or inclination of the 
rock, which was about 45°. The rock was sandstone, and percolation 
took place between the joints or fractures in the strata. On the remo- 
val of the cesspool to a distant part of the premises the water became 
decidedly better. The account of this remarkable case was published 
by Dr. Pinkham, of Lynn, in Scribner’s Monthly for 1877. 
From the brief study we have made of this subject in this lecture 
we may sum up the following conclusions to which we should care- 
fully give practical attention. 
On no account should we ever allow a cesspool, vault or surface 
privy within a radius from a well equal to twice its depth. 
No drain pipe, whether of iron or terra cotta, should ever be allowed 
within this distance on account of the danger of leakage. The best 
laid drains have been frequently found to leak in the most unexpected 
places, and where especial care had been taken to prevent it. 
In the case of houses on small lots of ground in a town wells ought 
never to be used at all for drinking. The Board of Health of such 
towns should have full legal power to close up all such wells, and 
remove the pumps, even if no positive disease has ever arisen from 
their use, or even if no complaint has been entered by a person residing 
in the immediate neighborhood. The Board of Health should also 
have power to prohibit any new wells being dug on premises of less 
than a certain fixed size. 
Where a system of sewerage exists cesspools should be totally pro- 
hibited under penalty of law, unless such cesspools are built absolutely 
water tight, and kept so, and are thoroughly ventilated by tall pipes 
or chimney stacks, and the contents are frequently and regularly 
removed. 
A certificate of compliance with these conditions given by regular 
official sanitary inspectors should be required at regular stated periods, 
say once a year, of every person having such cesspools on his premises. 
No new cesspools should be allowed under penalty of law, unless 
by a certificate granted by a regular official sanitary inspector. 
When a system of sewerage does not exist in a town the same law 
should be made to apply wherever the houses are not very scattered. 
In rural districts the law would be inapplicable. 
All wells located near sewers or under street pavements, or exposed 
to contamination from street gutters, should be immediately closed and 13 
the pumps removed. Such wells are extremely dangerous and a direct 
menace to the public health. In cases where a right of way to such a 
well is granted to several property holders by deed of title the Board 
of Health should have legal power to overcome resistance to its action 
so as to prevent all further use of the well, under penalty of law. 
A case of this kind has lately become known within the limits of 
Philadelphia, which I was requested to investigate. 
In all cases of refusal of property holders to comply with such 
requisitions of the Board of Health, the latter should have power to 
proceed as in ordinary cases of public nuisances. 
A modification of the law should be made so as to include within 
its prohibition all such wells as are likely, in the opinion of regu- 
larly constituted sanitary authority, to become polluted in the near 
future as well as those which are now actually in a polluted condition. 
[In his concluding remarks the lecturer spoke of the minute living 
animals found in river water, and exhibited by means of the lantern 
several photographs of animal and vegetable life found in the water 
supplied to London in 1851 and 1854, which were years when cholera 
was violently epidemic in that city.] 
These photographs are taken from plates in Dr. Hassal’s work on 
adulteration of food. I wish to express, however, my strong dis- 
sent from the opinions of Dr. Hassel as to the injurious character of 
these animals and diatoms themselves. I believe that no clear 
and positive evidence whatever has ever been brought forward 
to prove with any degree of certainty these forms of life themselves 
to have been the cause of disease. They could not have caused cholera 
in London, for many of them, nearly all perhaps, are stated to be 
found in the Schuylkill river water at the present time, and yet Phila- 
delphia was, at least in 1872, exceptionally free from cholera at a 
time when it was epidemic in other parts of the country. No disease 
has ever been proved attributable to these living forms in the Schuyl- 
kill river. 
The chief point to be considered is, what may be associated with 
these animalculEe and upon which they may feed, or in some way be the 
indication of its presence. Some of them, undoubtedly, live only in 
comparatively good water, in proof of which statement, the reader is 
referred to the work of Dr. Macdonald on the microscopic analysis of 
water. Some of them require a polluted water, and one which con- 
tains sewage in not too great amount will often be crowded with some 14 
forms, as was the case with some of the London water, which in 
1851 and for some years after, was taken from the river at the 
London bridges, where contamination with sewage was very great. 
These animalcule, therefore, may be an indication of organic filth in 
the water, and this filth may be excreted from the intestines of diseased 
people. The animalcule themselves are probably no more injurious 
to a human being than raw oysters. In all probability they can be 
digested with equal rapidity, and there is, as far as we know, no pos- 
sible way for them to get into the blood in a living state. 
[Photographs were also exhibited of the fresh-water algte which 
were the cause of the disagreeable pig-pen odor in the Poston water a 
few years ago. These were from plates drawn by Prof. Farlow, of 
Harvard, for his paper in the Massachusetts State Board of Health 
Report for 1879.]