Outlines of rural hygiene for physicians, students, and sanitarians

t(in©s oj' i

»»^^YGIENE

nJMHHW^IWIt*'-''

IHarVej^ B,Bast|orc M-

HvLtt a|olb0c of SKgriculture

^t (dorneU InttJeraitH

laaii'ir^t^im luiniversity Library

Outlines of rural hygiene for physicians

3 1924 003 449 505

Cornell University
Library

The original of tliis book is in
tlie Cornell University Library.

There are no known copyright restrictions in
the United States on the use of the text.

http://www.archive.org/details/cu31924003449505

OUTLINES

OF

RURAL Hygiene

FOR PHYSICIANS, STUDENTS, AND
SANITARIANS.

HARVEY B. BASHORE, M.D.,

Inspector for thk Statb Board of Healtk of Pennsylvania.

WITH AN APPENDIX

ON

The Normal Distribution of Cliloriiie.

By Pkop. HERBERT E. SMITH,

OF Yale Universitv.

IIiIiUSTRATED.

Philadelphia, New York, Chicago :
THE F. A. DAVIS COMPANY, PUBLISHERS.

1897.

PREFACE.

The almost absolute neglect of sanitary rules in districts
outside of the great cities, and the absence of special atten-
tion to this branch of sanitation in the larger and more
elaborate treatises, have called forth this work.

That it may aid in the difEusal of sanitary knowledge
where most needed, and that it may assist those who labor
in rural districts, is the earnest wish of the author.

Much of the substance of the work has appeared from
time to time in various medical periodicals, but all has been
carefully revised.

The author has drawn largely from numerous Health
Reports, and hereby acknowledges his obligation to all such
as are not especially mentioned.

Hahvey B. Bashohe.

West Fairview, Pa.,
November 1, 1897.

(iii)

CONTENTS.

CHAPTEE I.

PAGE

Wateh-supply 1

Wells. Cisterns. Elvers, Lakes, and Springs.
Examination of Wells and Well-water.

CHAPTEE II.

Waste Disposal 35

Excreta. Slop-waters. Kitchen Eefuse (Garbage).
Ashes, Crockery, etc. Sewage Disposal.

CHAPTEE III.

The Soil 48

Surface-soil. Ground-moisture. Ground-water.
Ground-air.

CHAPTEE IV.

Habitatioxs 56

Dwellings. School-hygiene. Hospitals.

CHAPTEE V
Disposal of the Dead 68

APPENDIX.
The Normal Distribution op Chlorine 71

Index 79

(V)

CHAPTER I.

Watee-supplt.

Wells. — Almost the whole of the rural population de-
pends upon shallow wells for its water-supply, and much
of the sanitary oversight occuiTing in these districts centres
about this point. Many an epidemic has been traced to such
a source, — small household epidemics they generally are;
sometimes, however, the "town-pump" becomes infected,
and a whole village suffers. A case of this kind lately hap-
pened in one of the small towns of Pennsylvania; almost
the entire population drank water from a single well; this
became infected, and, as a result, sixty out of the eighty
inhabitants became ill with typhoid fever and ten died.
Another striking case of well-water infection is that re-
ported by Volz, which occurred at Gerlachsheim, in Ger-
many. Here, in three weeks, fifty-two persons were attacked
with typhoid fever. On investigation it was found that
these had all gotten their water from a certain well, which
had been polluted by the discharges of the first patient.

In one of the State Health Reports there occurs the fol-
lowing very instructive note, which illustrates the point

in question: "While riding with Dr. , on his way to

see a patient, he pointed to a farm-house which he said
had a strange history. He had practiced in the adjoining
village for thirty years; the farm was occupied by tenants,

(1)

2 OUTLINES OF KURAL HYGIENE.

who were changed every few years, and during these thirty
years every family that lived on the place passed through
typhoid fever." Surely here was a house with a "skeleton
in the closet"; rather, I suppose we ought to say, in the
well; for there can be no reasonable doubt, from what we
know at present of the genesis of typhoid fever, that this
trouble was caused by an infected well or spring. Almost
everyone of us who has an acquaintance with the country
can point to certain districts where, year after year, as
autumn approaches, we have had one or two fever cases.

The source of infection in these old wells is, of course,
the infected ground-water, which, in its turn, has been
poisoned by some leaking cess-pool, or privy, or surface-
washings; in this connection it must not' be forgotten that
the discharges from a single case of typhoid may be the
source of danger. Such was the fact in the famous Plym-
outh epidemic, which, while not well-water infection, was
in a body of water vastly larger than many wells, and shows
how much greater the danger in a narrow, shallow well.

The distance from the well at which a source of infec-
tion becomes dangerous cannot be readily expressed in fig-
ures without the most careful study, for it depends entirely
on the character of the strata and the direction and velocity
of the ground-water currents. I recall to mind a very good
illustration of this, in which a well, situated hardly fifty
feet from a privy, shows almost absolutely no pollution,
while another, almost two hundred feet from the nearest
privy or other means of pollution, shows thirty times the

WATEE-SUPPLY. 3

normal chlorine of the region. In the first instance the
well is in a bed of compact impermeable clay, and, in the
second, a stratum of loose slate.

It is, perhaps, needless to state that the mere pollution
of a well by sewage is likely of no danger whatsoever unless
the germs of disease find an entrance; but, when a well is
exposed to leakage from human waste, it is so easy for
germs to follow, and so easy for them to grow in water laden
•with organic material, that there is always an element of
danger in using a water which is at all subject to privy leak-
age; the danger may not be very great, — ordinarily it is
not, — ^btit it exists, nevertheless. There are wells in every
town which, though undoubtedly polluted by leakage from
adjoining privies, have furnished drinking-water for many
years and have never yet been accused of conveying disease.
This, however, is no argument against the case; only a proof
that none or few germs have entered the well.

A point of much importance, as indicated before, is the
geological character of the strata which are pierced by the
well; yet this very rarely receives much more than a passing
attention. Modern investigation along this line has shown
that, for example, the distinction which the older works on
hygiene used to draw between deep and shallow wells
is of but very limited value. Deep wells, according to
the definition, are those which pass through an imper-
vious stratum and draw water from a deeper layer be-
neath; but this can only happen in a geological basin, and
geological basins are few and far between. At London and

4 OUTLINES OF KUEAL HYGIENE.

Paris there happens to be just such a formation, and con-
sequently deep wells are a great improvement over shallow
ones. On Manhattan Island, however, on the other hand,
a well may be a thousand feet deep and still not be a "deep"
well in a sanitary sense, for the strata there are more or less
perpendicular, which, of course, in a measure, excludes an
impervious layer; so it is over almost the whole of the vast
Appalachian region. Along the coast, however, the strata

granite' a

Fig. 1. — Section of the Strata Underlj'ing Paris aud its Environs.
Horizontal scale, eighty miles to an inch ; vertical scale, two
thousand feet to an inch. (From Humber's " Water-supply
of Cities and Towns.")

are in places, more or less horizontal, — or, rather, they are
parts of some great basin, — and are available for deep wells.
Whenever these Artesian wells are possible, they gener-
ally yield a very pure water. Much work has recently been
done in this subject on the Atlantic-Coast plain, and
maps are now being prepared by certain of the State
Geological Surveys which locate the water-bearing zones.
In New Jersey, for example, there have been found to be

WATER-SUPPLY. 5

three very important horizons. The first, 300 to 400 feet
deep, in mioeene strata; the second in the cretaceous; and
the third still lower. These beds all furnish excellent water,
and are used practically in many places along the coast, —
especially by large manufacturing plants.

Geological investigation, too, has shown that in a region
of upturned strata not only are deep wells impossible, but

Fig. 3. — CroBS-section of a Region of Upturned Strata. (Original.)

that wells of any sort are especially dangerous, unless much
attention is given to the location of the sources of pollution,
for the cleavage-lines of the rock-layers afford most excel-
lent drains for any surface or cess-pool waters which may
happen to be in the locality if the strata should incline in
the direction of the well. This is shown in the following
practical sketch, which represents a region in which the
rock-layers are almost perpendicular. In places like this.

b OUTLINES OF EUEAL HYGIENE.

ii" you are going to dig a well^ it makes a great difference
whether the eyer-present privy or cess-pool is located at
A or B. Suppose it is at B or in any place within 90° on
either side; then the well will almost certainly be contami-
nated, for the leaking water will only have to follow the
cleavage-lines in order to reach the well, and this it will
do most readily.^ The only possible location for a filth-
receptacle in the neighborhood of the well G is in the
direction of A, where the cleavage runs away from the well,
instead of to it as on the opposite side. The privy, if there
is one in the direction of B, should be absolutely no nearer
than — in fact, not so near as — the calculated distance,^ for,
if it is, there is sure to be pollution.

' In a region like the one described it is very ea.sy to calculate just
how far beyond the well in the direction of B (Fig. 2) the danger-line
extends. Knowing the depth oi the well and the angle of dip of the
strata (this is told by an instrument known as the "clinometer " ), we
construct a triangle as follows : —

B A =^ depth of well ; angle C = dip of strata, — i.e. the angle
made by a horizontal line on the surface with the cleavage-lines of the
slate. B is, of course, a right angle. To get angle A we add and B

WATEE-SUPPLT. 7

Important points these are; yet it is very rare indeed
that they are considered in making a well; biit they must
be heeded if one expects to get water at all approaching
purity.

The author's attention was recently called to a well
situated in just such a region, — a tube-well, about a hun-
dren feet deep, with its upper twenty or thirty feet sur-
rounded by an iron tube, and yet this water yielded 10.4
parts of chlorine per 100,000, while the normal chlorine of
the region is only 0.15 per 100,000. Neighboring privies
rested on the upturned slates within the region indicated by
B (Fig. 2), and, of necessity, the well was polluted. That
the well was deep only increased its drainage-area without
increasing in proportion its filtering properties, for water
filters very little in passing through the fracture-lines of a
rock-bed. Incidentally I might mention that a number of
eases of typhoid fever have been recurring yearly in the
vicinity of this well.

In a limestone region wells are likewise dangerous on

and subtract the result from 180°. Then, according to trigonometric
formula, we have side B A and angle A to find side a. This is solved
hy the formula a ^^ c X tan. A. Example : "We have a well 80 feet
deep represented hy B A or c. We find the dip of the strata to be 43° ;
add this to 90°, — a right angle, — ^and subtract this from 180°, we get
47° for angle A. Now, by substituting the figures in the formula, we
have (i = 80 X tan. 47°, or a = 80 X 1.07 = 85 feet. That is, that
within 85 feet of the well in the direction of B there is exceptional
danger, as within that distance all the cleavage-lines of the slate fall
within the well ; beyond this distance these lines fall short of the well,
and, of course, the danger is not nearly so great.

8 OUTLINES OF EUEAL HYGIENE.

account of the many underground seams which transmit
water with great facility; when water passes through these
caves it is not benefited by the natural filtering properties
of the soil, and infection in this way may travel a great
distance. A limestone country is generally honey-combed
by caverns of vast extent. In the limestone bluffs west of
Harrisburg I was once shown a cave into which a dog had
disappeared in pursuit of a fox; the story runs that the
dog came to the surface thirty miles away, and I think it
not altogether impossible. In such regions there are a great
many "sink-holes," which are simply surface connections
with underground caverns; through these, surface-water
pours in its downward course, infecting ground-water which
may come to the surface in some far-distant spring. A case
of this kind happened some time ago at Bethlehem, Pa.
This town suffered from a typhoid epidemic which was
finally traced to its water-supply; but how this became in-
fected was a puzzle, for their water-supply came from one
of those wild, virgin springs which, to all outward appear-
ances, is the synonym for purity; but at last large water-
bearing courses were discovered (it was a limestone region)
which had carried the infection from far-away privies.

Another formation worth study by the rural well-driller
is the clay; these beds are almost impervious to water, and
what docs pass through a short distance is generally filtered;
many a well owes its freedom from disease-producing germs
to the fact that it is surrounded by a stratum of clay.

Gravel, on the other hand, presents directly opposite

WATEE-STJPPLY. 9

qualities. The same property which makes a gravel-bed
good for building purposes — i.e., because drainage is good
and a dry foundation is obtainable — makes it very bad for
wells, for it is so porous that there can hardly be any hope
of its yielding an uncontaminated water, if there is any
means of contamination within a reasonable distance.

Such are some of the considerations which arise when
one is in search of a good well-water; but, irrespective of
any of these and without care or study, wells have been
dug everywhere, and consequently are almost everywhere
polluted. The question is at once asked: Can anything be
done with these old wells whereby they may be rendered
safe as a source of drinking-water? If possible, it would
be best to completely eliminate them and obtain some other
supply. When this is not feasible, the well, if not too
grossly polluted, may be rendered more or less safe by a
method devised by Dr. Koch.

Koch's Method. — Suppose that we have one of these
wells which yields a polluted water. To begin with, we
take out the pump, if there is one, and pour in sand until
it reaches within a foot or two of the lowest water-level;
the lowest level of the ground-water generally occurs at
the end of a dry, hot summer, and for this reason such a
time should be selected for the application of this method.
We now place in the centre of the well an iron tube three
or four inches in diameter, with its lower end expanded and
perforated. This end of the tube rests on the sand and,
while it is held in place, a bushel or two of fine gravel is

10

OtTTLINES OF EUHAL HYGIENE.

thrown in immediately surrounding it, and the well is then
completely filled with sand. Fig. 3 is the section of such
a well, the dotted line representing the water-level. If
now a pump is attached to the tube, we have a very good
tube-well, which differs from an ordinary one in that it is

Fig. 3.— Section of Well Treated by Koch's Metiiod. (Original.)

surrounded by a filtering layer of sand; probably this is the
best that can be done with a dug well. For a polluted tube-
well our only resource is to seek another supply.

The next question to be answered is: How may a well
be constructed, if at all, in order to meet modern sanitary

WATER-SUPPLY. 11

requirements? While we must admit that this is hard to
do, in the face of probable ground-water contamination,
still, under certain conditions, there are certain kind's of
wells which seem to give satisfaction; for example, in some
places deep Artesian wells will yield the best possible re-
sults; biit this, of course, is only over regions in which the
strata are approximately horizontal. The ordinary tube-
well cannot be recommended any more than a dug well, if
the strata incline much from the horizontal; in such a case,
if there is no other supply available, a dug well, filled with
sand after Dr. Koch's method, would be far safer than any
ordinary boring; this is true not only for regions of dis-
located strata, but also for beds of limestone, sandstone, or
loose rock of any kind.

In other places a shallow well, made according to the
directions of Professor Poore, of University College, Lon-
don, might give complete satisfaction, and, though the
places where this could be used are limited, the method is
worth some study. The following description of this ex-
perimental well made by Professor Poore is taken from the
Lancet: "The well was sunk in the very centre of a garden
which is rather profusely manured with human excreta; it
is placed at the intersection of two paths, — a broad, green
one, bordering one of asphalt. The situation was chosen
for two reasons: (1) that it was, as far as possible, removed
from any accidental pollution from the sewer in the street,
and (2) that in the centre of the garden it would theoreti-
cally run the greatest chance of fecal contamination from

13 OUTLINES OF EUKAL HYGIENE.

the manure used. As the well was sunk wholly for experi-
ment, this was essential. The garden is on a riyer-bank
(Thames) and very slightly raised above the level of the
water. The well is only 5 feet deep, and the water
stands at a level (which varies slightly) of about 3 feet 6
inches from the bottom. The well is lined throughout —
from the very bottom to a point some five inches above the
ground — ^with large, concrete sewer-pipes 2 feet 8 inches
in diameter, and these pipes have been carefully cemented
ah their junction; outside the pipes a circle of cement con-
crete about four inches thick has been run in. It will thus
be evident, the sides being perfectly protected, that no
water can possibly enter this well except through the
bottom, all contamination by lateral soakage through the
walls being rendered impossible. The well is surrounded
by an asphalt path about three feet wide and slightly slop-
ing away from it; around this is a hedge about five feet
high except at those points where the hedge is cut by the
paths. There is a closely-fitting cover of oak, wliich has an
outer casing of lead, and thus all contamination from above
is prevented.

"The water is drawn through a two-inch lead pipe which
passes through the outer concrete and the concrete lining-
pipe, the cut passage for the pipe being carefully closed with
cement. The pump is behind the hedge and is provided
with a sink and waste-pipe which takes the overflow some
twenty or thirty yards to a neighboring stream. In this
way the constant dropping of water in the neighborhood

WATER-SUPPLY.

13

of the well is prevented. I regard the question of overflow
one of greatest importance, which is too often neglected.
The nearest point to the well upon which any manural
deposit of excreta is likely to be made is on the far side
of the hedge; and the distance of this point from the bottom
of the well is seven feet. All water which finds its way
into the well must have passed through at least six or seven

Fig. 4. — Section of Professor Poore's Well, Showing Concrete
Lining and Position of Pump. The diagonal line on the right
is to mark the distance from nearest garden-bed to bottom
of well. (London Lancet.^

feet of earth, and, of course, the greater bulk of the water
has passed through a far greater length. Three chemical
analyses of this water — one by Professor Franldand and
two by Dr. Kenwood — testify to its organic purity, and
three bacteriological investigations have given similar indi-
cations of purity."

"While this well which Professor Poors constructed yields
pure water, it is no proof that all wells so constructed will.
The banks of the Thames are composed of an alluvial clay,

14 OUTLINES OF KUEAL HYGIENE.

which, of course, is very impervious to drainage and leakage;
and it is very likely that Professor Poore has made his well
in this deposit. As he has talcen great pains to keep out
surface waters, any drainage which may soak through the
adjacent soil would, of necessity, be considerably purified.
So much for this kind of well when made in elay-beds;
but suppose it is dug in a stratum of slate or sandstone;
suppose that the strata are tilted on edge, as represented
in Pig. 2, which would be a very likely case almost any-
where in Eastern United States. From what has been said
before one would hardly feel safe in drinking the water
from such a well, if human excreta were scattered over the
adjoining fields in the locality of B (Pig. 2); assuredly not,
if the excreta contained typhoid or cholera germs.

The fact is that one can never construct a perfect well
by any given rule; he must make a careful study of the
locality and the nature and dip of the strata if he would
have a pure water, and even then it is hard to get it un-
polluted from wells of any kind except, perhaps. Artesian.
Par better to select some other source of supply, preferably
the one next mentioned, which seems to the author to be
the ideal one for many isolated places.

Cisterns. — -In most localities in the United States, rain-
water stored in properly-constructed cisterns furnishes a
substitute for well-water, which is practicable and easily
available, for all we need is a suitable collecting surface and
a suitable cistern.

In the Atlantic States the annual rain-fall is about

WATER-SUPPLY. 15

thirty-seven inches, — an amount which, with the ordinary
house-roof for the collecting surface, is amply adequate and
absolutely reliable; of course, if we live in a district where
the rain-fall is less, a corresponding increase in the size of
the cistern and collecting surface is necessary to meet the
requirements of a continuous supply. If the house-roof
is something like one thousand square feet, — and many
houses will furnish even more, — the yearly yield of rain-
water collectable will be, if the annual precipitation is
thirty-seven inches, about 20,000 gallons, which, at ten
gallons per head per day, is more than sufficient for the
wants of an ordinary family. For this amount the cistern
need not be excessively large; one ten feet in diameter and
five feet deep will hold 2000 gallons, and this would last,
under usual conditions, more than a month; the danger
of exhausting the supply would not be great, for it is rare
indeed that a month passes, in most parts of the country,
without some precipitation.

The construction of the cistern is of the utmost impor-
tance, for in its ability to keep out soil-water rests the
superiority of the cistern over the well. If made of bricks
and thoroughly cemented it will be proof, in most cases,
against this contamination from the soil. I have known
such a cistern to last many years without leakage.

In the next place, we need a filter, for rain-water, unless
it is collected from a purer source than is generally the case,
has a peculiar flavor and odor. In order to make a filtering
cistern out of an ordinary one it is first necessary to build

16

OUTLINES OF EUHAL HYGIENE.

a partition from the bottom almost reaching to the top;
at the bottom there are several openings connecting the two

/;/,^ -,.^

>'•.'- \'f '.'.', !'.,

1 i 1 i f ) 1 I I rn

Fig. 5. — Section of Filtering-cistern. (Original.)

sides. Another way to do this filtering is to make two cis-
terns side by side and connect them by pipes, but the method
of having one cistern with a partition is cheaper, and, per-

WATEH-SUPPLY. 17

haps, better, as there is less danger of leakage. In construct-
ing the filter, which is placed on either side of the partition,
we may use a variety of substances; three or four feet of
common sand is probably the best and the cheapest material
that can be obtained. When a natural sand-filter is used
in the open air the upper layer of sand becomes covered by
a film of nitrifying bacteria, which is of the greatest value
in purifying the water. Although this sand-layer in the
cistern is cut off from sunlight, it gets an ample supply of
oxygen, and it is likely that it acts, in a measure, like the
open-air filters. Of all the different materials which we
may use, the one I prefer is made of three layers, each con-
sisting, from above downward, of sand, polarite, and gravel.
Whether this, however, is much better than one made of
ordinary sand is a question. Into the side containing the
filter the leader from the roof discharges, and into the other
is fixed the pump. This arrangement is readily understood
by reference to the figure. The water which passes to the
pump in a cistern like this is securely filtered, and we get a
good, pure, and harmless drinking-water. The sink under
the pump-spout may be perforated and empty directly into
the side of the cistern containing the filter, so that there
is no waste of water.

While this method of proctiring drinking-water is less
expensive than any other way, it is almost universally ne-
glected by the very people whom it would most benefit, —
the rural population. As long as the cistern is impervious
to the ground-water, there is no danger of its contents be-

3

18 OUTLINES OF HUEAL HYGIENE.

coming infected except by gross carelessness, — filth is some-
how or other gotten in at the top.

One can very readily tell if the cistern leaks by making
a simple chlorine examination of the water and then com-
paring it with the amount of chlorine found in rain-water
collected in a clean receptacle somewhere on the surface.
It is evident that much deviation of the chlorine from the
average of a surface collection will point to leakage in the
cistern.

Cistern-water, even without a filter, is vastly better and
vastly safer than any well; and if the collection is made from
a tin roof kept moderately clean, the water will be almost
odorless, fresh, and palatable; such water the writer has
frequently u.sed.

The collecting surface — whether tin, wood, or slate —
should be protected from overhanging trees, and a "cut-off"
should be placed in the spouting, so that the first washings
from the roof may be turned into the street gutter; in this
way dust, droppings of birds, etc., are washed away before
the water is allowed to run into the cistern.

The use of rain-water, too, furnishes a means whereby
the rural householder may have water under pressure in his
house, if he so desires. To have this great comfort people
generally think it necessary to have an hydraulic ram, a
force-pump, or some other expensive arrangement. By using
rain-water all one needs is a tank placed in one of the upper
vacant rooms and a series of distributing pipes to the bath,
kitchen, or wherever one wishes running water. The tank

WATEK-SUPPLT. 19

is large or small according to the needs of the service. Into
the tank a branch pipe with a "cut-off" leads from the
roof-spouting; when the tank is filled the "cut-off" is turned
and the water goes in another direction. The only care
necessary is to see^ from time to time, that the tank does not
get empty and that it is cleaned at proper intervals. In
one instance where this kind of water-service was used, the
stable-roof was also utilized. A tank was placed in the loft
and the leader from the roof turned into it; by this means
the stable was furnished with water and there was a plenti-
ful supply for watering the adjacent garden and lawn.

Rivers, Lakes, and Springs. — Many small towns are be-
ginning to seek a public water-supply from neighboring
rivers, lakes, or springs. Such a source would seem desir-
able in a good many eases; but giving a town water-pipes
without sewer-pipes is like putting the cart before the horse,
unless we first teach the people how to make suitable drains
and how to make and use earth-closets; if they use cess-
pools — and that is what they always do use when there is a
public water-service — the polluted soil-water will event-
ually soak into the water-pipes, and the "last state will be
worse than the first."

While any ordinary mountain-stream would seem, on first
thought, to furnish a pure and undefiled water, there are
certain points to be considered before selecting such a
supply. On account of the limited gathering-grounds of a
small stream, there is much more danger of infection than
in a large river. The discharges of one typhoid patient,

3Q OUTLINES OF EUEAL HYGIENE.

placed on the banks of the Susquehanna or the Delaware,
is not likely to cause danger to any great extent, but similar
discharges on the banks of a narrow mountain-brook caused
the fearful epidemic of Plymouth; so, on this score alone,
the "babbling brook" is not as ideal a source of supply as
some large river. In selecting a stream, lake, or spring,
other things being equal, we should take one having a wild,
uncultivated, and uninhabited gathering-ground, and this
should be, by all means, under the supervision of the people
using the water.

The pollution of public water-supplies is an interesting
and instructive study; sometimes the water is actually
fouled by sewers from the very town itself; the people are,
in fact, drinking their own waste. This is the case with
Harrisburg, Penna., where the intake of the city-works
opens into the river only a short distance from the shore
and directly below the mouths of several sewers.

In rivers flowing through coal regions there is another
kind of pollution which sometimes enters into the question
of a water-supply; while the regions where this occurs are
not very numerous, it is still worth noting. This pollution
is caused by drainage-water from coal mines; it consists
chemically of a solution of protosulphate of iron, and forms,
when concentrated, a black, turbid stream from its sus-
pended coal-dust; when more diluted, it is of a peculiar sul-
phury color, and gives a white deposit on rocks lining its
course. In Pennsylvania this goes by the name of "sulphur-
i^'pter"; but this is a misnomer, for the color is due, not to

WATEE-SUPPLY. 31

sulphur, but to oxide of iron. The protosulphate, which is
about the only important chemical constituent, decomposes
under the influence of sunlight and oxygen, and yields a
sequisulphate and a hydrated oxide; so much we know from
the laboratory of the chemist, and there is no reason to
believe that the result is any difEerent outside of the labora-
tory. The oxide, however, is not a bad thing, for it assists
somewhat in purifying the water, but the sesquisulphate
is an astringent which, when it comes in contact with tannic
acid of tea or coffee, has a tendency to make tannate of iron,
and tannate of iron is popularly known as "ink." For this
reason waters contaminated with mine-drainage are not suit-
able for town-supplies, and not only that, but they destroy
more or less the vegetable and animal life in their respective
courses.

I have seen small streams in Northern Pennsylvania
which were as black as ink, and a good deal thicker, from
this drainage. No living thing inhabits their waters nor
seeks their banks, — a Nineteenth Century representation of
the fabled Styx.

To purify a stream encumbered by mine-drainage, it is
necessary to filter it through beds of limestone; by this
means the sulphate of iron is changed into sulphate of lime,
which is harmless, although it adds some hardness to the
water. The excessive amount of free coal-dust which these
waters sometimes carry may be removed by any kind of a
gravel or broken-stone filter. In some of the large rivers
this drainage occupies only a small part of its width, and

23 OUTLINES OF HUKAL HYGIENE.

water for drinking may be obtained by extending the water-
pipes beyond the "sulphur-stream."

Examination of Wells and Well-water. — The physician
in isolated localities is frequently called upon to give an
opinion as to whether or not a certain well is fit for use.
He has to depend iipon his own resources, and it is neces-
sary that the examination be as simple as possible and at
the same time reliable. Each well is a factor by itself, and '
should be studied as to the geological strata which it pierces,
the position of the sources of possible pollution, and the
relative amoiint of chlorine it contains. The old idea that
a well drains a cone-shaped area whose base is from fifty to
one hundred times its depth approximates, perhaps, the
truth, but so much depends on the character of the rock-
strata that is is impossible to lay down any definite rule;
it makes all the difference in the world whether the well
taps the ground-water through a thick, heavy clay, or
whether it draws its supply from a gravel-bed, from slate,
sandstone, limestone, or a more impervious rock; it makes
much difference whether the strata are horizontal or "turned
on edge." The proximity of a source of pollution counts
for little as to a distance in feet; the position studied in
regard to the slope of the strata and the direction of the
ground-water currents mean much more in laying bare a
source of trouble.

In examining the water we want to find out if it con-
tains pathogenic germs or if it is likely to. The detection of
these is probably not available to many country practition-

WATER-SUPPLY. 33

ers. Disease-germs only come into a drinking-water through
the medium of organic waste, and, in the absence of our
ability to detect the germs, we have to be satisfied with the
detection of the pollution with which the germs are asso-
ciated, — sewage, privy, stable leakage, etc. If a well shows
that it is not polluted with such material, it is most likely
free of pathogenic germs, and is almost certainly not a
factor in producing disease.

To find out this kind of pollution a simple chlorine ex-
amination is generally all that is necessary. I do not, for
a moment, depreciate the elaborate analyses for organic
matter, nitrates, etc., but these are not available in the out-
lying districts, and they are not actually necessary in a good
many cases of well-water examination, especially in times
of epidemics. If we know the normal chlorine of the region
(see "Appendix") — i.e., the amount of chlorine present in
unpolluted springs and rivers — we can readily Judge the
amoiTnt of pollution of a given water; of course, chlorine in
a water may represent only past pollution, but in a sanitary
way this does not count for much, for we can never tell at
what moment the old lines of drainage might not' be re-
established, and for that reason a well once polluted pre-
sents an ever-present danger, unless the source of former
pollution can be absolutely abolished.

Although we judge the amount of pollution by the vari-
ation from the normal chlorine, we should not make this
absolute and condemn every well which shows excess, for
some excess above the normal, although pointing almost

24

OUTLINES OF EUEAL HYGIENE.

positively to pollution, is allowable and does not necessarilj'
mean dangerous pollution.

What each physician should do, if he lives in a locality
supplied by well-water, is to ascertain the chlorine normal
of the district, and, if a well shows a water containing
chlorine much above this amount, it should be viewed with
suspicion and judgment passed accordingly.

The following list, taken from several Health Reports,
gives an idea of the amount of chlorine in certain waters
not excessively polluted: —

Naugatauk River, 0.16 parts per 100,000.

Charles River, 0.43-0.80

Housatonic River, 0.16

Croton River, 0.44

Schuylkill River, 0.57

Delaware River, 0.25

Spring, Penna., 0.50

Spring, Conn., 0.17

Well, Penna., 0.20

CHAPTEE II.

Waste Disposal.

The disposal of waste in country places presents features
entirely different from that of a city, inasmuch as in the
country this duty depends upon individual efEort, and indi-
vidual effort, be it ever so good, is a poor substitute for
municipal oversight where sewage and garbage disposal and
every other sanitary requirement must conform to a definite
rule.

Excreta. — First in order, and perhaps, too, in impor-
tance, comes the disposal of human excreta; and this, in the
absence of water-service, is very important, for we have
learned that one of the most common causes of preventable
diseases in the country comes from well-water polluted by
leakage from cess-pools and privies. If there is one sanitary
necessity which stands pre-eminently above all the rest, it
is, probably, the substitution of the earth-closet for these
foul privies and cess-pools, which undoubtedly contaminate
the ground-water. We know so little about the changes of
the water in the soil and so little about the life-history of
the germs of certain water-borne diseases, that there is
danger whenever the ground-water is exposed to excreta. It
is a fact that the privies in most villages are rarely emptied,
and one sanitarian has explained this on the supposition
that the wells draw a good deal of their water from the

(35)

36 OUTLINES OF EUEAL HYGIENE.

urine of neighboring privies; and this can very readily be
the state of affairs in many places.

Privies should be absolutely abolished unless they are
placed far from any well and made perfectly water-tight.
Instead of a privy-yault, it is better to use dry earth-closets.
In the average country town not one person in a thousand
uses an earth-closet or, in fact, seems to know anything
about it. If we could get village dwellers to understand the
sanitary value of this method of excretal disposal, it would
be a great step in progress. There are very many ways and
methods of making these dry closets. The following, which
is one of the simplest, is that recommended by the Penn-
sylvania State Board of Health; it is so easily made that
there is no excuse why every rural dweller should not have
one: —

"The body is a plain pine box; its sides are 14 inches
high, its depth 18 inches, and length about 30 inches. It is
divided into two compartments, — one 18x18 inches and the
other 18x13 inches. The larger of these compartments has
no bottom; the smaller is a tight one. On top are two
covers. The lower one, hinged to the upper edge of the
back, extends all the way across both compartments. In
this lower cover is cut the seat,^ — over the centre of the
larger compartment. The upper cover is hinged to the
lower one and may be raised independently; it is made the
size of the large compartment, and both have a little edge
projecting to facilitate lifting them." The receiving vessel
is a gal vani zed-iron bucket (an old coal-bucket will answer)

28 OUTLINES OF EUEAL HYGIENE.

as large as will stand in the compartment with the covers
down. The small compartment is filled with dry, sifted
anthracite coal ashes, or whatever else is used, a scoop placed
in it, and the commode is ready for use.

After using, the lower cover is raised, exposing both
compartments. A small quantity of the ashes is then taken
in the scoop and scattered over the contents of the hod. A
closet such as this may be placed anywhere in the house
or in the old privy, and with proper care is absolutely odor-
less. The material for use in these closets may be either
ashes or dry earth; in summer dry earth may be taken
directly from the garden-bed, exposed to the sun for a short
time, and, for use in winter, stored in barrels. Ashes —
finely sifted from anthracite coal — are perhaps better, if
the closet is in the house, for the ashes are lighter and more
absorbent; dry earth, if much urine is allowed to pass into
the hopper, becomes muddy and heavy.

The disposal of the contents of the closet is, perhaps,
the stumbling-block to many. This material, whether ashes
or earth has been used, may be placed on a corner of the
garden-bed and covered with a little earth, or it may be
buried a few inches under the soil; lastly, it may be kept
in a dry place, covered with earth and carted away at some
suitable time by the farmer for use as fertilizer. In places
where earth or ashes are scarce the contents may be allowed
to humify in a dry shed and this humus used again; this
may be repeated many times. The agent of disposal in all
cases is the nitrifying bacteria. To be sure, if too much ash

WASTE DISPOSAL.

29

is used, nitrification is delayed; but with the mixture of a
little earth the organic matter all disappears in due time.

Last year I made some experiments in regard to the
length of time required for the disposal of excreta when

Fig. 7.— A Model Dry Closet. (Original.)

buried under four or five inches of soil. In summer the
time was about two weeks, which corresponds to the time
obseryed by Professor Poore. In January — ^in the coldest
month of the year — the excreta, when mixed with ashes

30 OUTLINES OF EUEAL HYGIENE.

and buried, had completely disappeared in four weeks, al-
though most of the time the surface-soil was completely
frozen, and at the time of examination was so hard that I
had to use a pick.

If one desires a more elaborate commode it may be made
somewhat after the manner of the modern water-closet. A
design of this fashion is shown in Kg. 7. The pail is made
of ornamental agateware, and upon this rests the seat of
mahogany, walnut, or oak, exactly the same as is used in
the water-closet. A pail which is open in this manner pos-
sesses the advantages of the open water-closet in that there
h no hiding-place for dirt. The ashes may be kept in a
box beside the pail.

Another way of using the earth-closet, especially for
schools or large dwellings, is to have a privy constructed
with what is called a "dry catch." A pit is dug, about three
feet deep, which has its two sides, front, and back lined with
brick; in the back an open space is left for a door of wire
netting, and an inclined pathway is made from the bottom
of the closet to the surface, unless the privy should happen
to be built on the side of a hill, when this would not, of
course, be necessary.

The floor of the vault is concreted and inclined as in-
dicated in the drawing. The urine which is voided flows
backward into a gutter, which is filled with some absorbent,
— sawdust, ashes, or dry earth.

The pan under the seat is made of galvanized iron, and
a flap is attached to the lower end to prevent an upward

Fig. 8.—" Dry-Catch " Privy. (Modified, after Poore.)

32 OUTLINES OF RUBAL HYGIENE.

draft; this flap may be balanced so as to work automatically,
01' may be worked by a chain. After use, earth or ashes is
put in the pan just as in any other closet.

In a privy of this sort the humification of the fasces will
continue, although no earth is added. Poore narrates a
case where, by neglect of the scavenger, the "contents had
not been removed for two months; still the bottom of the
mass had humified and become inoffensive." The proper
way for such a closet to be utilized by country schools
would be to have a reservoir filled with an absorbent, so
arranged that pulling a chain would throw a sufficient
amount into the pan, or what, perhaps, is better, is simply
to have the Janitor throw earth over the contents of the
closet once every day; every week or two, according to cir-
cumstances, the mass should be removed.

To get people to use dry closets is more a question of
education than of legislation. A town that purposes this
innovation should have printed circulars sent to all house-
holders, showing the advantages of the method. Then they
might order the construction of all privies after the method
shown in Fig. 8, and have a public scavenger clean them
every week. The personal influence of the physician and
his example in these sanitary matters will do much to en-
lighten the people to a correct understanding of the value
of sanitary appliances; and, until the people are educated
to this point, legislation will hardly do much good.

Slop-waters. — For the purpose of studying this part of
our subject vs^e have to consider three classes of country

WASTE DISPOSAL. 33

houses: First, those which have water-service and use
water-closets for the disposal of excreta just as in the city;
this, of course, necessitates the use of sewers, in which the
slop-waters are also disposed of. With these we have noth-
ing to do, so far as the individual treatment of waste-water
is concerned. Secondly, those in which, although having
water-service, the excreta are disposed of by some form of
dry closet; in this class sewers are not needed, but drains
are necessary for carrying the waste-waters from the kitchen
sink and bath. Thirdly, those which have no water-service,
no bath, etc. This comprises, by far, the greater number of-
houses outside the cities and large towns. In the latter
class all slops — which amoimt in a family of four or five to
about fifteen gallons daily — are collected in buckets and
are generally emptied out the kitchen door, irrespective of
where the filthy water may flow. In such a house a slop-
bowl should be put in some convenient location either in
the house, on the porch, balcony, or elsewhere, and con-
nected with a surface- or subsoil- drain, both of which have
points of excellence.

In the simplest form of a drain the pipe from the slop-
bowl may lead to a furrow in the vegetable bed. A bettei'
arrangement is that shown in the accompanying photo-
graph, which was taken from a small drain in actual use.
This drain was made for one of our third-class houses,
which have no water-service. A box about a foot square,
lined with tin or galvanized iron, was placed in a suitable
location — in this instance, at the corner of the bed to be

3

34 OUTLINES OF ETIEAL HYGIENE.

used — ^to serve as a receptacle for the slop- waters which are
collected in buckets; from this extends, an old tin roof-gutter
in any direction available. The bottom of the box is per-
forated by twenty or thirty small holes, which serve to let
the water into the gutter. A number of small holes is
better bhan a few large ones, as the small tend to keep solid
particles out of the gutter and prevent clogging. The
gutter is twenty feet long; it is nine inches above the ground
at the upper end and three inches at the lower, in order to
give sufficient fall for its rapid emptying, — a very necessary
iactor in cold weather. The gutter is pierced every three or
four inches by one-fourth to one-half inch holes, which per-
mit the liqiud to flow on to the soil, where it is quickly
absorbed. The soil needs a little raking now and then to
favor absorption and evaporation. Along each side of the
drain may be planted a hedge of laurel, a row of sunflowers,
or any vegetable which happens to be desirable, only that
all debris from overhanging plants must be kept out of the
gutter. This kind of a drain will do very well in houses
having water-service, by simply having the waste-pipe from
the kitchen and bath discharge into the gutter.

An important point in the use of this drain — as, in fact,
of any drain — ^is to keep solid and liquid refuse separate, —
for a liquid containing many solid particles tends to choke
it and to interfere with its efficiency. This separation is
readily accomplished by keeping two buckets in or near the
kitchen,^ — one for solids and one for liquids. Over the one
is placed a tin basin with a perforated bottom; the semi-

Fig. 9. — One Form of Surface-drain, Made of a Tin Roof-gutter.

WASTE DISPOSAL. S?

liquid waste, as it comes from the kitchen, is placed in the
basin, the water drains through, and the solid refuse is
emptied into the other bucket. In Fig. 9 these buckets are
shown adjoining the drain.

In the winter a surface-drain may cause trouble unless
some care is taken. In the first place, it should be kept
clean of snow, and, in the next, the liquid must be emptied
into the drain before it is chilled by long exposure to the
cold; but if proper attention is paid to these points and to
the thorough emptying of the drain each time that it is
used, it will give complete satisfaction, even in the coldest
weather.

Another way of making a surface-drain is to construct
a gutter of perforated bricks, the space underneath the
gutter being prepared by trenching and filling with small
stones, cinders, and the like, to favor absorption. Instead
of perforated bricks, the ordinary ones may be used by leav-
ing an interval of half an inch or so between each brick. A
drain of this sort has the advantage of being easily cleaned
by sweeping. A number of English physicians are said to
favor this plan very much.

A very good drain, too, may be made by digging a trench
a foot or so deep and a couple of feet wide, and lining it with
small, round, cobble-stones, such as are used in some street
gutters. The space, of course, underneath the drain should
be prepared with some absorbent material, and the waste-
pipe should discharge a foot or so above the bottom of the
gutter, so as to permit no undue accumulation .of ice in

38 OUTLINES OF HUEAL HYGIENE.

winter; the length of such a gutter should be fifteen or
twenty feet for a family of four or five. In this^ as in all
surface-drains, the waste-pipes need not be trapped.

A surface-gutter may be protected from freezing by
covering with some old boards and a little earth, making it
piactically a subsoil-drain^ for the time being.

In some places, for various sesthetic reasons, and espe-
cially in a very cold climate, a surface-drain may not be
practicable. Then we have to resort to a subsoil-drain,
which is made as follows: —

For this method several hundred feet of land are neces-
sary if all the wasta-water from the house is disposed in one
place; but in many instances different places for different
drains will be more suitable. In calculating the amount
of tiles, we may count one or two feet, depending on the
soil, for each gallon to be disposed daily. A trench is dug
about tM'o feet deep, and in this ordinary two-inch drain-
tiles are placed; it is best to rest the tiles on a narrow piece
of board in order to get them on a regular pitch, which
should be at least five inches in twenty feet. The tiles are
placed about half an inch apart, and the joints are covered
with broken stones or half-pipes; then the whole trench is
filled with stones, coarse coal ashes or cinders completely
surrounding the tiles, and finally covered with earth. The
delivery-pipe from the house is connected to the drain by
a lead or iron pipe, which projects into the end tile. At the
far end of every line of tiling a pipe should be inserted, and
project above the ground, so as to allow the free circulation

Fi"-

10. — Surface-drain Made of Ordinary Bi'icks, Siiowiiig De-
livery-pipe from Kitciien Sink and Batli.

WASTE DISPOSAL. 41

of air through the drain. Suhsoil drains, if made in this
way, cause very little odor in the room; but, as a precaution-
ary measure, they should be trapped. In a case in which
more than a single line of tile is necessary the field may be

T K <y ( ) ( PC n r

Fig. 11.— Method of Laying Tiles for Subsoil-drain.

laid out in a variety of ways; the only point necessary is to
have a sufficient interval — two or three feet — ^between each
line.

The kitchen sink and the bath may be directly con-
nected to such a drain, either together or separately.

Fig. 13.— Plan of Subsoil Irrigation-bed.

For the disposal of the bedroom-slops a slop-bowl may
be placed in the bath-room, or wherever most convenient.

In some such manner as this we dispose absolutely of all
the waste-waters of a house Just as well, perhaps a good deal
better and safer than we could with sewers.

43 OtrTLINES OF EUEAL HYGIENE.

In the first class of houses — those having water-service
and sewers — there comes up the question of sewage disposal,
which almost invariably means a cess-pool. Instead of a
cess-pool, a small shallow tank should be built at some suit-
able place, more or less distant from the house, and at the
edge of some cultivated field, counting about one hundred
sqiiare feet of land for each individual. There are flush-
tanks constructed for placing underground; but this is
hardly necessary, unless the location selected should happen
to be very near the dwelling. The house-sewer is connected
with the tank, and an automatic flush controls the distri-
bution of the sewage, which should be discharged inter-
mittently. A gutter made of cement, or half-pipe, is laid
from the tank along the field to be iised, and every dozen
feet or so there is a little branch gutter to guide the sewage
over the land. In front of each of these branches there is
a barrier of broken stones, to check the flow and prevent
washing, and beyond this the land to be used, which should
be planted with corn, as this does not keep out sunlight as
much as grain, and sunlight is an important factor in sew-
age farming.

Garbage. — Sweepings, paper, rags, ashes, and solid
refuse from the kitchen make another chapter in waste dis-
posal. In cities this goes under the head of garbage and is
disposed by various methods, in many cases destruction by
fire giving the greatest satisfaction. In cities under good
sanitary control ashes are kept separate from the other
material, and we do likewise in the country. Most of the

Fig. 13. — Photograph Showing Distributing-gutter and Stone Barrier
of au Iriigatiou-fiekl. (New .Jersey State Board of Health
Report. )

WASTE DISPOSAL. 45

solid refvise, save the ashes, is probably best gotten rid of
by fire, and it is generally recommended that the kitchen
range be the medium of disposal. To do this properly there
must be a good fire in the range, and too much waste must
not be put in at once. With proper care almost all kitchen
refuse, orange- and potato- parings, egg-shells, bones, etc.,
can be destroyed without trouble. The only disadvantage is
that this sometimes causes an odor. To obviate this an
apparatus has been devised for attachment to the stove-pipe,
whereby the material is first carbonized by the heat passing
up the chimney, before throwing it into the fire. I have
no practical experience with this arrangement, but judge
from the various reports that it answers well.

Kitchen waste may also be disposed of by simply bury-
ing it a few inches under the soil. A hole several feet
square may be dug in the garden-bed and the refuse emptied
into it and covered with earth from time to time. In this
way the material is disposed of by nitrification,— in a month
or so, — and the soil is made the richer. When land is avail-
able, — and it does not take much, — this method is the most
efficient means, perhaps, for disposing of putrescible gar-
bage. Combustible waste — as rags, paper, sweepings, bones,
and the like — can be disposed better by fire.

The following is another method for the destruction of
putrescible waste, which may be of value in certain places:
"Take a piece of galvanized wire netting three or four feet
wide, and with it inclose a circular space about three or four
feet in diameter, the netting being fastened and supported

46 OUTLINES OF EURAL HTGIBNB.

by two or three iron or wooden stakes driven into the
ground. Into this little wire inclosure throw all refuse from
the house and garden which is capable of rotting, the par-
ings and waste of yegetables and other food, the mowings
and sweepings of the lawn and paths, weeds, fallen leaves,
etc. Such a heap as this, exposed on all sides to the air,
is not offensive, and the component parts of it undergo
humifaetion. When the wire inclosure will hold no more,
a little earth must be thrown on top, and the heap must be
left for several weeks freely exposed to the weather. It will
settle down and diminish in bulk, and finally is entirely con-
verted into fine garden-mold suitable for potting or for
enriching the soil. The final act in the management of this
refuse heap is to sift it and consign the residue to the garden
bonfire. When one netting inclosure is filled, a second
must be formed; so that in connection with a house there
must always be two heaps, — one forming and the other
ripening. Such heaps, if freely exposed on all sides, are not,
ir the smallest degree, offensive."

The other part of the garbage — the ashes, broken crock-
ery, tin cans, etc. — should be kept separate and used for
filling. If an ash-closet is used almost all the ashes will be
disposed in this way.

The waste, then, of an ideal country house would be
disposed somewhat as follows: The material from the dry
closet — which is the only method of excretal disposal rec-
ommended when there is no water-service — is to be used
as fertilizer by burying a few inches in cultivated soil either

WASTE DISPOSAL. 47

on the garden-bed or on a neighboring farm. The waste-
ivater from the kitchen sink and the bath run into lines of
surface- or subsoil- drains. The garbage — that is, the putres-
dible part which comes from the kitchen — is burned in the
range or buried in a pit in the garden-bed. The combust-
ible part — ^rags and paper — is burned. The non-combust-
ible part — ashes, tin cans, oyster-shells, etc. — is piit into
bags kept for the purpose, and at intervals is taken away
and used for filling. In houses where there is water-service ,
and water-closets excreta and slop-waters are disposed to-
gether in the form of sewage, and for this the only means
of disposal is irrigation. The cess-pool should not be
thought of.

CHAPTEE III.

The Soil.

The study of the soil and rocks used to belong strictly
to the geologist, but lately the biologist and the sanitarian
have taken up the work, and we are finding that there are
factors in the soil which have much bearing on health. For
example, there is the surface-soil, with its peculiar filth-
destroying properties; ground-moisture and ground-water
present problems to be solved; ground-air, too, is a question
of vast importance.

The surface-soil is composed of the debris of the subsoil
mixed with more or less humus; this humus is the black
soil, or mold, which is produced by the decomposition of
the organic matter of plants and animals; surface-soil,
though to a superficial observer apparently dead, is filled
with all varieties of lowly life, — ^worms, bacteria, bugs, and
beetles, which work out the problem of their existence vastly
better than some forms of higher life.

It is only in the upper few feet of the soil that is carried
on all the various processes for the feeding and clothing of
the race, — a vast laboratory, as it were, of which we know
very little.

As far as sanitarians are concerned, the most important
part played by this "living earth," as it has been called, is
its ability to destroy waste-material and to break up such
(48)

THE SOIL. 49

matter into its primary elementSj rendering them harmless,
and fit to be taken up by growing plant-life.

The process of decay and disorganization was noted long
ago, but we never knew exactly what it meant until very
recently. Wow we call it nitrification, and the world has to
thank Sehloessing, Miintz, Warrington, and "Winogradski
for the work that they have done; but much yet remains
unknown, for not one of these nitrifying organisms has been
isolated, unless we except the bacillococcus of Prankland;
not one has been cultivated. These bacteria, only known,
as yet, by their effects, are the great scavengers of the world,
for they are present in all natural and cultivated soils.

The products of nitrification are ammonia, nitrites,
and nitrates, and ihe last is plant-food. It is not just yet
settled whether nitration — the formation of nitrites into
nitrates- — is chemical or biological, but the evidence seems
to point to the former, and that it is brought about by the
action of the carbon dioxide and the oxygeh of the ground-
air. Sewage-farms, filter-beds, earth-closets, and all like
destroj'ers of filth depend, for their efficiency, on nitrifica-
tion. When we add earth to the dry closet we simply add
nitrifying bacteria plus an absorbent. Could we isolate these
bacteria it might be better to add them separately, but we
have not progressed so far; so we add the bacteria in their
natural habitat.

The nitrifying properties of different soils depend on
various circumstances, such as the nature of the soil, aera-
tion, moisture, and heat, the thermal life-point varying

50 OUTLINES OF RUEAL HYGIENE.

with different organisms. Excessive heat destroys the nitri-
fying bacteria; so that earth dried in an oven is absolutely
useless — save as an absorbent — for the earth-closet.

Germicides kill them; so that adding carbolic acid to a
compost-heap or a privy is useles as far as the ultimate dis-
posal is concerned, for, while the acid might kill some path-
ogenic germs and destroy noxious odors for the time being,
it also impedes the nitrifying germs.

Ground-moisture, — If one digs into the earth he finds
that the upper layers are moist, containing both air and
water. This dampness is derived from percolating waters
from above and from the ground-water below, which tends
to rise by capillary action and hydrostatic pressure. Ground-
moisture is directly proportional to the absorptive power of
the soil, and inversely as its permeability, both of which
depend on the character of the soil and varies accordingly;
for example, humus will retain about 50 per cent, of water;
slate, 4 to 10 per cent.; sandstone, 3 to 8 per cent.; lime-
stone, only 2 to 3 per cent. It is evident that by increasing
the permeability of the soil we can diminish its dampness;
to do this we fill trenches with some loose rock or debris of
any kind, or we may lay a course of drain-tiles. Water pre-
colating through the soil will collect in these trenches or
tiles, flow off rapidly, and the soil will become drier.

This undue dampness of the soil is, no doubt, a factor
in certain diseases. The prevalence of rheumatic com-
plaints in rural districts, where the houses are almost uni-
versally damp, is a well-known fact, strikingly different

THE SOIL. 51

from its prevalence iii a well-drained city. Of course, there
are other factors at work; but soil-dampness is certainly one
not to be ignored.

It has been claimed that there is a relationship between
dampness and phthisis. According to some English statis-
ticSj there seems to have been a great lowering of phthisical
mortality following subsoil-drainage in certain localities.
We now know that phthisis is a specific disease; but it
appears likely that continual exposure to dampness so lowers
vitality that the bacilli find a better breeding-ground than
in the normal condition.

One other disease — namely, malaria — has much depend-
ence apparently on excessive ground-moisture; this, with
heat and organic matter, seems to be a primal factor in the
breeding of the plasmodium. It has been noted that in-
creased dryness of the soil, which is brought about by sur-
face- and subsoil- drainage, is a potent factor in the destruc-
tion of malaria. Eucalyptus, sunflowers, and other plants
which absorb much moisture are great aids to drainage.
Sunflowers, especially, as they will grow almost anywhere,
are to be recommended for wet places aboxit country homes.

Ground-water, as explained before, is that underground
sheet of water which completely fills all the interstices of
the soil at a certain depth, extending from, several feet to
hundreds of feet below the surface; its heiglit is readily
told by the height of water in the wells of the district. This
ground-water does not flow in rivers, as is generally sup-
posed, but extends underneath the soil in one broad, con-

53

OUTLINES OF KUEAL HYGIENE.

tinuous sheet; it is for this reason that wells sunk almost
anywhere yield water.

The origin of the groimd-water is, of course, the rain
sinking through a porous soil; its level varies from time to
time and does not extend in a horizontal line, but in an
irregular one, the fluctuations depending on the geological
character of the rock and the precipitation and height of
adjoining water-courses. At Munich, for example, there is
a difference of ten feet between the highest and lowest

Fig. 14. — ShowiDg Ground- water Level, in an Elevated Region
Between Two Streams. (Original.)

levels. In summers characterized by long droughts the
water-courses become very low, and consequently the
ground-water sinks below its usual place; as a result, many
wells get "dry." The proper time to dig a well, if such
things must exist, is during a dry summer, when the ground-
water is at its lowest point.

The sheet of ground-water is also in continual motion
toward the nearest water-courses; five to ten feet per day
gives some idea of its_ velocity, which changes with the
porosity of the bed. In some regions of limestone, slate,

THE SOIL.

53

and sandstone there are large underground cavities and fis-
sures, through which water-movement is greatly facilitated.
Much has been said about the relation of the ground-
water to diseases, and especially its connection with typhoid
fever. The theory of Professor Pettenkofer, that low

—

1

/
f
/

•

/

><:

^

V
V

V

V

K --

Fig. 1.5. (From Miers and Crosskey.)

ground-water and epidemics of typhoid fever occur simul-
taneously, cannot be verified for all places. The following
sketch of these relations for the city of Zurich in 1873
shows the exact opposite. Of course, if a city uses wells or a
polluted drinking-water of any kind, Pettenkofer's theory
rests on a logical basis, for the increase of drainage and

54 OUTLINES OF EUEAL HYGIENE.

consequent wider area of infection brought about by low
ground-water will readily explain the spread of the disease.

The truth of the ground-water question seems to be that
unless its level is very near the surface it has little to do
with health save in the pollution of water-supplies. I recall
a town where the ground-water is generally twenty-five to
fifty feet below the surface, yet almost every house in that
town is damp and unhealthy, because faulty constniction
has permitted ground-air and ground-moisture to permeate
the foundations. Much has .been said about lowering the
ground-water by drainage; but ordinarily it is a difficult
thing to do this. When people speak of lowering the
ground-water by building sewers and drains, they generally
mean that they lessen ground-moisture and dampness.

Ground-air, — More important than ground-water is the
air which occupies the upper layers of the soil and fills all
the interstices as far down, at least, as the surface of the
ground-water. The composition of this air and its move-
ments are the two factors ^\■hich interest sanitarians. De-
composition and putrefaction are constantly going on in
the soil, and the gases arising from these processes diffuse
through the soil. The carbon unites with the oxygen of
the atmosphere, and carbon dioxide is formed, which is
always greater in the ground-air than in the atmosphere;
for example, at Dresden, where experiments were made, at
six feet beneath the surface there was found to be 3.99 per
cent., aud at eighteen feet 7.9G per cent., of caxbon dioxide.
Oxygen, on the other hand, is decreased, and falls as low as

THE SOIL. 55

10 per cent, in some soils. Nitrogen remains at about the
same proportion as in the atmosphere.

These gases, together with certain amounts of ammonia,
hydrogen, ammonium sulphide, and marsh-gas, make up the
air in the soil. Thus, difEering in composition from the
atmosphere, it is not suitable for breathing purposes, and is
too damp. On the other hand, we are not certain that it
does not, at times, contain the spores of certain disease-
germs.

The second disturbing factor of the ground-air — namely,
its movement — is of considerable sanitary importance. It
has been proved that winds blowing against the surface set
this underground-air in motion; likewise, too, any change
in the ground-water level will occasion fluctuations in the
air above. Also during a heavy rain the surface-waters
flowing downward press upon the ground-air and compress
itj underneath a dwelling, if the cellar is not properly con-
creted, there is an area of diminished pressure, and conse-
quently the ground-air pours into the cellar and thence
into the house. In winter, during heavy frosts, when the
frozen ground is more or less impervious, the warm, un-
frozen part underneath a house facilitates the ascent of the
ground-air; hence the reason for urging more careful biiild-
ing of cellars and foundations than at present.

GHAPTEE IV.

Habitatiohts.

Dwellings. — The first thing in the building of a house,
not only to the architect, but also to the sanitarian, is the
foundation. That very little attention is paid to this will
bo apparent to anyone who will watch the construction of a
foundation, especially in the rural districts. Whether the
land to be used is wet or dry, clay or gravel, sandstone, slate,
or granite, the method is nearly always the same, — simply
a hole in the ground, walled with stone, upon which is to
rest the superstructure.

The foundation is intended to serve, not only as a firm
support for the building, bu t also as a barrier to the moist-
ure and the damp, unwholesome air of the soil.

After a building site is selected it is necessary to see
that it is thoroughly drained by surface- and subsoil- drains;
the latter consist of tiles or ditches partially filled with
broken stones, gravel, or sand, and is graded, if possible, to
a suitable outlet. Colonel Waring, the eminent sanitary en-
gineer, has so well described the details of this work that
I take the liberty to quote him without reserve: "In the
case of a country house, or of a town house standing in the
centre of a considerable area, it is often the most efficient
means for securing satisfactory drainage to apply a very
thorough system of under draining to the whole area about
(56)

HABITATIONS.

57

it and for some distance away, by laying different lines of
drains, not necessarily under the house at all, but so as to
surround it on all sides from which water flows toward it,
and in all eases at a depth of several feet below the level of
the cellar-bottom. In the construction of these drains two
courses may be pursued with, perhaps, an equally good
result. One is, after having excavated the ditch and cleared

Fig. 16. — Gravel Drain Under Cellar-floor. (From " The Principles
and Practice of House-drainage," Century Magazine.)

its bottom of all loose dirt, to fill in to a depth of a foot
with sand or gravel, — and even fine sand will answer the
purpose. The other is to use agricultural drain-tiles, — pref-
erably of the smallest size; say, an inch and a quarter in
diameter, — laid at the bottom of a well-graded trench and
continued to point of outlet. When tiles are used, the
joints should be wrapped twice around with strips of muslin
drawn tight. This makes a perfect collar, holding the tiles

58 OUTLINES OF EtJEAL HYGIENE.

in line and affording much the best proteetion that has yet
been devised against the ingress of sand or silt, which usu-
ally finds its entrance at the lower part of the joint, flowing
in with the water which rises with the ground-water level,
and flows off over the floor of the tile. A tile an inch and
a quarter in diameter will carry more water than can usu-
ally be collected for a constant flow from the subsoil of half
an acre of ground. A body of sand or gravel ten or twelve
inches wide and of equal depth cannot be so compacted —
provided clay and loam be kept out of it — ^that it will not
afford a free outlet for all the water that can reach it, under
these circumstances, from the soil of an ordinary lot. As
a rule, the tile will be found to be much cheaper than the
other material. It is better always that the depth of the
drain should not be less than three feet below the level of
the foot of the foundation. The more rapid the descent
the better, biit even two inches in a hundred feet, with
perfect grading, will remove a very large flow."

The ground-air, which nobody wants to have in his
house, is also kept out by proper attention to the founda-
tion; and I again quote from Colonel Waring a very effective
method of remedying this defect, which is universal in most
country houses and in a good many of the older city houses:
"One of the safest materials for a cellar-bottom and for
the external packing of foundation walls is a clean, smooth,
compact clay, one of which may be beaten into a close mass,
and which has a sufficient affinity for moisture always to
maintain its retentive condition, for, when used in the damp

HABITATIONS. 59

atmosphere of a cellar or about a foundation^ it seems to
constitute a good barrier to the passage of impure air. In
the cellar it may, of course, be covered with concrete for
cleanliness and good appearance; but six inches of clay,
fl'ell rammed while wet, will impede the movement of air
to a degree with which ordinary cellar concrete can furnish
no parallel. When clay is not available, a good smearing of
asphalt over the outside of the foundation-wall, and a thick
layer of asphalt between two thicknesses of concrete for the
cellar-bottom, will afford a complete, though more costly
protection. Asphalt used in substantially the same way,
especially if in connection with a solid course of slate or
North Eiver blue-stone, in the foundation above the ground-
level, will prevent the soaking up, into the structure, of the
moisture of a heavy soil."

Another way is to cover the cellar-floor with brick, on
edge, and then run melted pitch over this, and finally cover
with a layer of concrete or cement.

The ventilation and heating of country houses are points
worth considering, inasmuch as the majority of these houses
are heated by stoves and, as a result of defective arrange-
ment, the floors are always cold. In these stove-heated rooms
the floor is from six to eight degrees colder than it is four
or five feet above the floor. This means that one's feet are
just that many degrees colder than the head and shoulders.

To obviate this difficulty each room should be built so
that it has an open grate or its equivalent, — simply an air-
shaft connected with the chimney and opening into the

60 OUTLINES OF RURAL HYGIENE.

room at the floor-level; by this means good ventilation can al-
ways he obtained. Ventilating-stoves, although of value in
school-houses, are not necessary in private houses; with an
open grate, or an air-shaft, as indicated, a room may be very
well heated with an ordinary stove.

In Fig. 17 is shown the effect of heating a room with a
stove with and without a foul-air shaft. In the upper room
the heated air rises and fills the upper parts of the room,
while the floor remains cold; if the heating is brought to
such a point that the lower part does become warm, the
upper part is too hot, and, if a window is opened, the heated
air rushes out without warming the room, and leaves a lot
of foul air to be breathed. If now, as in the lower room,
there is an open grate, or an air-shaft in the chimney, the
heated air creates a partial vacuum, and a draft, conse-
quently, is constantly going up the chimney; in the room
this, of course, creates movement toward the opening, and,
as a result, the foul air is "sucked up" the chimney and
the upper, heated air is more difllused abotit the room, mak-
ing the temperature more uniform; in these cases fresh air
enters at the windows and doors. If the house is heated by
hot air, steam, or hot water by direct or direct-indirect
method (if there is no open grate), there should be an ex-
traction shaft at the lowest part of the room near the source
of entrance of the heat, as will he apparent from a study of
the diagrams in Mg. 19.

School-hygiene. — School-buildings in the coimtry are
excessively defective in sanitary arrangements; there are

5

Fig. 17. — Showing Effect of Heating a Room With and Without
Air-shaft. (Original.)

63 OUTLINES OF EUHAL HTG.IENE.

yery few model schools^ eyen in the great cities. In the first
placej the site for a school-house, as for any other human
habitation, should be located on a dry, well-drained soil,
and this is generally available in rural districts. There
should be ample play-ground around the building, and if
trees are planted they should not be placed so close as to
interfere with the lighting of the room, and the building
should be so planned that the windows face north and south,
for by this means we get the best light.

In the construction of the building we should be guided
by the same sanitary rules laid down for dwellings, and pro-
vision should be made for sufficient air- and fioor- space.
Each pupil should have about 300 cubic feet of air-space
with about 20 feet of floor-space; by changing the air in the
room — say six times an hour — we would give each indi-
vidual 1800 cubic feet of air per hour, which is surely not
too much. In New York City each pupil gets from 80 to
100 cubic feet of air-space, but it is generally conceded that
this is by far too little.

The fioor should be of polished, hard wood, with no
rugs nor carpets. The walls and ceiling should be painted
some green tint, as this is probably the easiest for the eyes;
above all, they should not be white.

Each room should not be more than 40 feet long, for
beyond this the distance to the blackboard becomes too
great. The windows should occupy one-fourth the floor-
space, should reach to the ceiling, and should not be covered
with shades; inside blinds are much better,

HABITATIONS. 63

"Water should be plentifully supplied^ but the usual
method of having an open bucket and a common cup for all
should be abolished. The water should be kept in a covered
bucket or a pitcher, and each pupil should have a small tin
cup attached to his or her desk.

Among other faults to be corrected are the seats, which
are often too high, and the crowding of too many children
in one room, thirty pupils being considered enough for one
teacher and for one room.

The ventilation and heating of country schools are yet
dene in the crudest possible manner. A stove furnishes the
heat, and ventilation, such as it is, is obtained through open
doors and windows. In winter, when we need heat for the
school-room, ventilation and heat may be obtained at the
same time by means of a ventilating-stove. ' This consists of
an ordinary stove inclosed by a cylinder of tin or galvanized
iron. The front part is movable on hinges, so as to allow
opening in order to get at the stove proper. Underneath
the stove a hole is cut into the floor, — at least two feet
square, if possible, — and this should be continued to the
outside air by a shaft made of wood or tin.

For the removal of foul air an opening should be made
into the chimney at the lowest part of the room, and not
farther removed than is actually necessary from the centre
of heat, as indicated in the heating of dwellings. An open-
ing at the top of the room — ^which is the place usually rec-
ommended for a foul-air shaft — only permits the escape of
heated air before it has been properly diffused, and coDse-

64

OUTLINES OF EUKAL HYGIENE.

quently does little good; If each room had an open grate —
which it ought to have — we would need nothing more.

Fig. 18. — Showing AvrangementB of Air-shafts for Ventilating-stove.

Heating a room by means of a stove is not an ideal way, but
it is the most available for country schools.

The privy attachment of these schools is even mor§

HABITATIONS. , 65

primitive than the heating and ventilation; it is generally
situated in the most public place in the yard, without any
covered passage-way or any other means to obviate exposure;
this is simply abominable. In place of the old-fashioned
privy the dry-earth system should be used (such as is men-
tioned on page 30), and should be connected with the build-
ing by a covered path; if there is someone to look after this
dry closet, it will yield most excellent results. The material
can be disposed to the neighboring farmer for fertilizer.

Emergency Hospitals. — Although in the larger towns
and cities a permanent isolation hospital is needed, this is
hardly necessary in the small towns and villages, for the
simple reason that when such a thing becomes necessary we
can use an ordinary tent, which makes the best kind of an
emergency hospital, — and tents are always procurable. If
the tent has a board floor and arrangements made for a
stove, it may be made very comfortable in any kind of
weather.

The plot selected for the erection of a hospital tent
should be dry and sheltered as much as possible, and the
free space surrounding the tent should be as large as is con-
veniently obtainable, not only for the sake of the fresh air,
but on account of the danger of contagion. Contagious dis-
eases, when isolated, do not appear to spread the disease,
save in the case of small-pox, and, as this is the one disease
which most likely would require isolation in the inland dis-
tricts, the proximity of human habitations is an important
question.

::^A

^ A,

Fig. 19. — Diagram, Showing Correct and Faulty Methods of Heat-
ing and Ventilation. (From Reports of United States Bureau
of Education.)

A, Inlet for heated air.

B, Outlet for foul air.

G, JD, E, F, G, Faulty.
ff, Correct.

HABITATIONS. 6?

Dr. Powers, of the Local Government Board (England),
during an investigation of this subject found that, in the
neighborhood of the London small-pox hospitals, the num-
ber of cases in the surrounding districts increased almost
in a direct ratio to the nearness of the hospital; this in-
crease, too, was independent of the lines of human inter-
course.

For diseases like typhus fever, when fresh air is most
necessary, nothing is comparable to tents for isolation. I
happened to be assistant on Blackwell's Island during the
last epidemic of that disease, and, although it was in winter,
tents were used for all cases, and they did remarkably well.

CHAPTER V.

Disposal of the Dead.

While in many places cremation of the dead presents
some advantages, there seems to be no doubt that in most
suburban districts, at least, earth-burial, if properly per-
formed, meets all sanitary requirements of the present, and
is ample proof against the transmission of disease.

In the first place, it must be recognized that the main
point in earth-burial is not the preservation of the body, but
its resolution, as rapidly as possible, into its primitive ele-
ments, with the minimum amount of discomfort and danger
to the living.

The prevalent custom of constructing a cemented brick
vault for the coffin is not desirable, for it delays decomposi-
tion; the sooner putrefaction is over, the sooner is the
danger past.

It has been found that in proper earth-burial the body is
destroyed rather rapidly by the action of numerous insects,
worms, and nitrifying bacteria. From experiments of Dr.
Poore we find that it takes something like two years for the
earth to dispose of the carcass of a cow or a horse; of course,
it should take no longer for a human cadaver, unless it is
protected by the enibalmer's art or by a vault.

We hear a good deal about the dangers of graveyards;
but all of these may be avoided by ordinary care. One of
(68)

DISPOSAL OP THE DEAD. 69

the dangers seems to come from embalming; for example,
the water of a certain creek which flows through Forrest
Lawn Cemetery in Buffalo was found, some time since, to be
impregnated with considerable quantities of arsenic of the
kind used by the embalmer, and had it not been discovered
might have been a factor in the death-rate.

Another danger which is supposed to come from grave-
yards is that of the transmission of contagious diseases. Sir
Spencer Wells quotes the following, which is worth repeat-
ing: "Some people living in a mountain country and hav-
ing very little communication with each other were in the
habit of quenching their thirst at a neighboring well after
the Sunday attendance at the district church. A young
man died of diphtheria and was buried in the yard. The
drinking from the well continued, and in a short time
twenty of those peasants were carried off by the sajne
disease. If asked how we are to account for this accident,
but on the presumption that the germs of this disease found
their way into the waters of the well, various explanations
— such as milk outbreak or personal communication — may
bo imagined; but none so exactly corresponds with the cir-
cumstances as leakage from the corpse." That such danger
as the above may exist, and be scientifically possible, it is
only necessary to refer to the investigations of Dr. Lossener,
who has shown that certain pathogenic germs exist for some
time in buried cadavers, even when decomposition is not
delayed. His results are as follow: —

Typhoid germs lived 96 days.

70 OUTLINES OP RURAL HYGIENE.

Cholera germs lived 28 days.

Tubercular germs lived 95 days.

Tetanus germs lived 234 to 361 days.

Anthrax germs lived 365 days.

These experiments of Lossener were carried on in nitri-
fying soils; but it must be remembered that a good many
graveyards are placed on the cheap non-nitrifying clays,
because they are cheap and not good for agriculture. Such
soils should not be selected for this purpose, for we are not
certain but that pathogenic germs may live much longer in
those cases in which decomposition is delayed; and in these
soils it is delayed very much, for nitrifying germs are absent.
It is recorded that in cutting through St. Andrew's church-
yard, Hoborn (England), which is situated on a heavy clay,
some of the bodies which had been buried even a hundred
years showed very little decomposition.

To have earth-burial effective then

1. There should be no embalming, save for transporta-
tion.

2. The body should not be placed, if avoidable, in a
sealed coffin or vault.

■ 3. Burial should not be deep.
4. The cemetery shoiild not be placed on a non-nitrify-
ing soil.

APPENDIX.

THE NOEMAL DISTRIBUTIOK OP CHLOEINE.^
By Pkof. Heebeet E. Smith.
Watbh, as it is foiind in springs, streams, lakes, etc.,
always contains chlorine in solution, chiefly, if not wholly,
in the form of common salt. Sometimes there is much,
sometiines little, but always some, even in waters which are
entirely free from the possibility of contamination by man.
Hence we must recognize that there are natural sources from
which water does derive chlorine. Biit there are also arti-
ficial sources, for the waste-fluids of certain manufacturing
processes, sewage, and even the drainage from inhabited
areas, contain considerable quantities of chlorine. The ad-
ditions of such liquids to a stream or pond must add to the
total amount of its chlorine.

If one knew the amount of natural chlorine in a given
water, it would only be necessary to subtract this from the
total amount found in analysis to determine the amount of
chlorine added from artificial sources. This at once gives,
as can readily be seen, a measure of the amount of the con-
tamination to which a water has been subjected, for chlorine

1 Professor Smith has kindly permitted the author to use his article
for this appendix. The article was originally a report to the Conneot-
iout State Board of TIealth.

(71)

72 APPENDIX.

once added to water remains in it, since it is not removed
by filtration, by sedimentation, or by the growth of plants,
by which means the other constituents of sewage contami-
nation may be largely or entirely i'emoved.

A knowledge of the amount of natural chlorine, or, as
it may be better called, the normal chlorine, of the waters of
a region is of great importance, therefore, as giving data for
correctly interpreting one of the important items of a sani-
tary water-analysis. That it is possible to determine within
reasonable limitations the normal chlorine of a region was
first demonstrated by the Massachusetts State Board of
Health, as one of the important scientific deductions from
the systematic analysis of the 'drinking-waters of that State.
In 1891, in the Eeport of the Connecticut State Board of
Health, there was also published a small map of this State,
containing data which had been obtained in the analysis of
our drinking-waters. These data showed that the chlorine
in the pure waters of Connecticut presented the same regu-
larity of distribution as in Massachusetts. Since that time
many more analyses have been made, and from the data
now at hand the accompanying map has been prepared.

On this map is shown the average amount of chlorine
found in waters which are considered suitable for the pur-
pose in various parts of the State. It will be seen that the
amounts vary from about one to six parts per million, and
further that the amounts are largest along the southern
border of the State, and decrease as one goes north and west.
The lines on the map are drawn through places which

THE NORMAL DISTEIBUTION OF CHLORINE. 73

appear to have the same average normal chlorine, — i.e., they
are isochlor-lines. By locating a sotirce of water on the
map, therefore, one can determine the amount of chlorine
which may be expected to be in it from natural sources.

The limitation of the use of such a map will become evi-
dent by a consideration of the sources of normal chlorine,
and an inspection of the data on which the map is founded.

The natural sources of chlorine in waters found in
springs, streams, ponds, and fresh- water lakes can only be:
First, from compounds of chlorine existing in the rocks and
soil with which the water has come in contact, and from
which it has dissolved them. Second, deposits of chlorine
compounds on the surface, as from spray blown in from
bodies of salt water. Third, from chlorine existing in rain-
water as it falls. What may be spoken of a geological chlo-
rine might come from deposits of common salt, and in cer-
tain regions this would certainly be an important source of
chlorine in many spring- waters. If the normal chlorine of
our waters was derived from small quantities of salt, or other
chlorides diffused in our rocks, or from minerals which
yield chlorine on decomposition, then spring- waters, after
percolating through the soil, would contain more chlorine
than small fresh-water ponds supplied with surface-water
from adjacent water-sheds. But this is not the case, for the
ground-waters do not contain more chlorine than spring-
waters of the same region; of course, this does not apply to
certain deep waters, which furnish, sometimes, large
amounts of chlorine, probably of geological origin. If the

'('4 ' APPENDIX.

normal chlorine of our surface- and spring- waters is not
geological in character, we must turn to the sea as its
source. That it is of marine origin is clearly shown hy a
study of the maps, for the amounts rapidly diminish in
zones marked hy lines approximately parallel to the coast-
lines.

Whether the salt is blown up from the surface of the
ocean as spray and carried inland hy the winds in the form
of dust which, falling to the earth, is dissolved by the fallen
rain, or whether the chlorine is blown inland during rain-
storms, is not significant. It would seem that salt might be
carried inland in both ways.

If the normal chlorine of our waters is due to that con-
tained in the rain, it is clear that it must exceed that found
ir the rain-water in proportion to the concentration effected
by evaporation. The amount of this evaporation may be
inferred from the relation of the flow of streams of a region
to its rain-fall.

The flow of Connecticut streams may be placed at about
60 per cent, of the annual rain-fall; consequently that part
of the normal chlorine due to chlorine in rain would be
expressed by increasing the chlorine of the rain according
to the ratio of 60 to 100. In the following tables is given,
in parts per million, the average chlorine in the rain at each
of the stations, and also the figures obtained by correcting
for evaporation in the ratio of 60 to 100, together with the
normal chlorine of the station, as derived from the chlorine
map.

THE NORMAL DISTHIBUTION OP CHLOKINE. 75

The agreement between the observed normal chlorine
and the figures calculated from the observations on the rain
is rather surprising, considering the errors to which the
method was subject.

Table Showing Avehage Chlorine in Eain in Com-

PABisoN WITH Normal Chlorine at

THE Same Station.

station. Rain CI. Corrected Normal

CI. CI.

Canaan 0.8 1.3 1.3

Waterbury 1.3 2.0 2.0

Hartford 1.3 3.2 1.8

Bridgeport 1.6 2.7 3.0

New Haven 2.0 3.3 3.2

New London 2.2 3.7 3.5

From the observations and considerations which have
been presented we must accept the proposition that the
normal chlorine is of marine origin, and is mostly conveyed
inland during rain-storms. This conclusion at once shows
us that the normal chlorine cannot be a fixed quantity at
any one place, but must vary from time to time with the
character of the storms. Eain-storms accompanied by high
southeast winds would appear especially favorable for carry-
ing salt inland over Connecticut. That the chlorine found
in our uncontaminated waters is not constant at any one
place is clearly shown by the various series of analyses form-
ing the data on which the map is based. The results from
any one source may vary as much as 5D to 100 per cent.,

76 APPENDIX.

especially when the amount of chlorine is small. Usually,
however, the variations from the average are less than this,
and for the most part do not amount to more than 0.5 part
per million. Obviously samples from small streams which
would be greatly influenced by any considerable rain-fall
must be less regular in the amount of chlorine which they
contain than samples from large reservoirs or lakes in which
the rain from many streams will be mixed. From this it
follows that, while the true condition of a large body of
water may be shown by a single analysis, a series of exami-
nations might be required from a small stream to obtain a
reliable average.

It is also obvious that the natural chlorine of a long-
stream is not that of the locality from which a sample may
happen to be taken, but is rather that of the average of its
water-shed above the place in question. For instance, the
average chlorine in the Connecticut Eiver at Goodspeed's
L,anding during 1890-'91 was 1.4, while the normal waters
of that region show about three parts of chlorine, and yet
the river receives large quantities of sewage from Hartford,
Middletown, and other towns draining into it.

The natural chlorine of the Connecticut Eiver must be ■
somewhat under one part per million, for the bulk of its
water comes from Massachusetts and above. In the light
of its normal, therefore, the contamination that exists at
Goodspeed's Landing is clearly seen, although the contami-
nation is not great enough to raise the chlorine from a low
normal up to the figures which would be normal at that

THE NOKMAL DISTEIBTJTION OF CHLORINE. 77

place, this being due to the great bulk of water which flows
in the river. Even a large amount of sewage discharged
into a stream may not increase the chlorine beyond the
natural variations during periods of large flowage. Usu-
ally, however, the effect becomes obvious in dry weather.
Along the sea-coast the variations in natural chlorine are
greater than they are further inland. This is seen in the
greater variations in the samples from the same source at
different times, and especially in the marked difference in
samples a short distance apart. This seems to depend, in
some instances,, on local conditions which favor the pre-
cipitation of the salt-laden rain or spray.

Fig. 30. — Map of Connecticul, Showing Distribution of Cbloriiie. Chlorine
is expressed in parts per million. The heavy lines indicate the normal
chlorine. The figures show observed chlorine iu waters which are
normal or nearly so.

INDEX.

PAGE

Air-space in schools 62

in New York City schools 62

Artesian wells 4

Atlantic-Coast plain 4

P-uffalo graveyard, dangei's, at 69

Cess-pools 42

Chlorine, examination for 23

in rain 75

natural 71, 72

normal 23, 24, 71-77

sources of 73

Cisterns • 14

construction of . . ; 15

filter for 15, 16, 17

leakage of 18

size of 15

Cistern-water 18

collection of 18

examination of 18

size of roof for collecting 15

Clay 8

Clays, non-nitrifying 70

Country houses, class of 32

Dead, disposal of 68

Poore's experiments on 68

Distance of well from privy, calculation of 6

Drain, subsoil 38, 41

amount of land needed for 38

amount of tiles 38

construction of : 38, 41 ,

79

80 INDEX.

I'AGE

Drain, surface 33, 37

of cobble-stones 37

of ordinary bricks 37, 39

of perforated bricks 37

of tin roof-gutter 34, 35

"Dry-catch" privy 30

Dry closet, model 29, 30

Dry earth-closets 26-28

absorbent for 28

contents, disposal of , ■• ■ ■ • 28

Dwellings 56

drain for foundation of 57

foundations of 56

ground-air in 58

materials for cellar-bottom of 58

ventilation and heating of 59

Earth-burial 68-70

LiSssener's experiments on 69

Emergency hospitals 65

Excreta 25

disposal of 28

experiments on disposal of 29

Floor-space 62

Foundations 56

asphalt in 59

Colonel Waring on 57, 58

external packing for 58

North River blue-stone in 59

Garbage 42, 47

combustible part of 47

non-combustible part of 47

putrescible part of 45, 47

separation of 42

INDEX. 81

PAGE

Geological strata 3

basins 3, 4

Germs, pathogenic, life of, in soil 69, 70

Graveyards, dangers of 69

Ground-air 54, 58

composition of 54

movements of 55

Ground-moisture 50

and malaria 51

and phthisis .51

Ground- water 51

and disease 53

level 9, 52

lowering of ; 54

movements 52

origin 52

Pettenkofer's theory of 53

Harrisburg sewage in river at 20

Heating 59

by stoves 59

with and without air-shafts 60, 61

of schools 63

Hoborn, Eng., church-yard at 70

Humus 48

absorptive power of 50

Irrigation bed, plan of subsoil 41

Irrigation field 42, 43 ,

Isochlor-lines 73

Kitchen sink 41

Koch, on treating old wells 9

Lakes 19

"Living earth,'' the 48

Lossener, on life of pathogenic germs 69

82 INDEX.

PAGE

Malaria 51

Manhattan Island, strata on 4

Mine drainage 20, 21

Muntz, on nitrification 49

Nitrification 49

products of 49

Nitrifying bacteria 49

Pettenkofer's theory 53

Phthisis 51

Plymouth, Pa., typhoid epidemic at 2, 20

. Polarite 17

Poore, on disposal of excreta 29

on dry-catch privy 30, 31

on earth-burial of cadaver 68

on humification of faeces 32

on shallow wells 11

Privy leakage , 2, 3

Privy vault 26

Eain-fall, annual 14

Kain-water 18

storage of ,. 14

River-water 19

Rooms, heating with stoves 60

Sehloessing, on nitrification 49

School-buildings 60

construction of 62

floor-space for 62

heating of 63

privy attachments of 64

seating capacity of 63

ventilation of 63

School-hygiene 60

"Sink-holes" s

INDKX. 83

PAGE

bed-room 41

disposal of 41

Soil, the 48

life of 48

nitrifying properties of 49

surface 48

Springs 19

"Sulphur-water" 20, 22

Tiles, mode of laying, for drains 41

Typhoid fever at Bethlehem, Pa 8

at Gerlachsheim 1

at Plymouth, Pa 20

Ventilating-stove 60, 63

arrangement of air-shafts for 64

Ventilation 59

Waring, Colonel, on drainage of building sites 56, 57

on foundation making 58, 59

Warrington, on nitrification 49

Waste disposal 25

Waste, kitchen 45

combustible 45, 47

non-combustible 45, 47

putrescible 45, 47

separation of solid and liquid 34

water 47

Water "under pressure" 18

Water-bearing zones, in cretaceous strata 5

in iniocene strata 5

in New Jersey 4

Waters, slop- 32

disposal of 33

Water-supply 1

in coal regions 20

pollution of 20

84 INDEX.

PAGE

Wells 1

artesian 4, 11

deep 3, 4

in clay 8

in gravel 8

in horizontal strata 11, 4

in limestone 7

in slate 3

in upturned strata 5, 14

shallow 11

tube 7, 11

Wells, Sir Spencer, on graveyard leakage 69

Well-water, chlorine in 23

examination of 22

Winogradski, on nitrification 49

Zurich, typhoid fever at 53