origin and geographical distribution, its persistence within any area, and its final decay; the history, in fact, of the relations of cholera, whether epidemic or endemic, wherever
its
may meet with it. Genebal Definitions. A.?The train of symptoms called cholera is
we
the effect of
object, under whatever conditions it may be manifested; the object, the presence of which brings about these symptoms, has the value in a natural history system of a species. B.?Endemic cholera is the cholera of a distinctly defined geographical area, within which it is perennially existent. C.?Epidemic cholera is the cholera of all regions beyond the the action of
one
and the same
limits of the endemic area. An epidemic cholera originates
primarily within the endemic area, and the cholera of the epidemic area has separate aspects under two different conditions : the first is that of an invading cholera, shown while cholera is in course of distribution over definite portions of the epidemic area; the second is as a reproduced cholera, renewed over definite portions of the epidemic area in months or years subsequent to its original distribution. D.?AVithin the epidemic area, a cholera which has made its invasion necessarily dies out within a certain definite period (probably three years) ; and if cases of cholera come forward after the termination of this
period, they are generally isolated and may be regarded as indicative of the presence of a cholera whose vitality has become impaired, or of a cholera in an abortive state. usually fatal,
are not
systematise the entire series of phenomena, may at seem an impossibility ; but the sequence in which I propose to bring the various aspects of cholera before you, may help us, starting from a sure foundation, to add one series of truths to another, of which the sum total may serve to form the 1.
first
To
sight
basis of a system. 2. The facts and illustrations I must ask you to accept: as facts ; the hypotheses which I may adduce as deductions from the collected facts, I ask you to discuss with me, in order
that my interpretation of their significance may be tested by
judgment and experience. The general conclusion to which my study of the subject leads is this,?that there is nothing casual or fortuitous in the occurrence of cholera in any locality or at any season ; but that every epidemic, every outbreak, and indeed any case of cholera has a definite position in a grand system. 4. The special data from which the conclusions arrived at, are drawn, are the results of the experience of upwards of a hundred and fifty thousand individuals daily under European medical observation. The study has extended over a period of eleven year's, viz., from 1856 to the present date ; and the statistical results have been systematically arranged from the original official documents by my own hand. The above numbers iuclude the European Army in Bengal, averaging, with women and children, about 50,000 ; the Native Army, numbering about 60,000 ; and prisoners, averaging about 52,000 in each year.
your 3.
The area of observation extends from the Assam Frontier the East, to Nagpore and the Valley of the Nerbudda on the South and West, and from the North-Western Frontier to
on
the Bay of Bengal. This includes the countries
SUGGESTIONS FOR THE SYSTEMATIC STUDY OF THE HISTORY AND RELATIONS OF CHOLERA. By JAMES L. BIIYDEN, M.D., Assistant-Surgeon, Her Majesty's Bengal Army. I iiave been asked to indicate to
you*
the
general phenomena
exhibited by the Cholera of this Presidency, in connexion with * This Communication was originally read before ference at Simla.?Ed., I, M. O.
a
Professional Con-
31? North, and longitude 70? 5.
The
following
to
lying between latitude 20? to 96? .East.
is the order in which I wish to
various sections of my subject before you
bring
the
:?
geographical distribution of cholera I shall take the cholera of the twelve years 1855 to 1866 inclusive, and show what has been in each year the geographical distribution and limit of epidemic cholera, and A.?Phenomena of the
in this
Presidency.
define the areas which have been
those which have been exempted,
occupied
in each year, and
I shall try to show the
THE INDIAN MEDICAL GAZETTE.
284
laws of limitation, the laws of distribution, and the laws of exemption. B.?The phenomena of the invasion of an unoccupied area. This section will treat of the origin of an invading cholera, of the direction in which an epidemic cholera invades, and the relation which it bears to the agencies which control its progress. C.?"Will treat of the behaviour of sequent to its invasion of an epidemic
aspect of a reproduced cholera as
epidemic cholera subprovince ; and of the distinguished from a cholera in
actual course of distribution. Under this head will be discussed the
questions,?what pheno-
proper to cholera as an object of natural history ; at what seasons it shall come forward in epidemic or local manifestation, according to its geographical situation; and what
mena
are
agencies shall accelerate, or epidcmic spread.
and what shall retard its re-appearance
In this section the laws regulating the final decay and disappearance of epidemic cholera may also be treated of. D.?Here we may try to determine what amount of truth lies in the assertions, that cholera is propagated locally by to man, and is in this certain geographical area ; and that the
transmission of the miasm from manner
spread
over
a
man
cholera miasm may multiply itself within the human economy, finding there a suitable nidus for rapid propagation. The important questions?what conditions tend to bring about the localisation of cholera, and upon what rational grounds does the system of the avoidance of cholera by marching away from an affected locality rest, may here be taken up. of the history of the cholera of these twelve years with the history of cholera in the past, in order to determine how far the phenomena of cholera are permanent, and consequently under fixed laws; how far, E.?A
comparison
the
we
of
may anticipate past experience, cholera in any year, and in any localiwe may ty, before its actual invasion or outbreak; how
ground upon the occurrence of
march
troops in any province of this Presidency so as to cholera, the meeting with which is at present regarded as inevitable; and how, in anticipation of an approaching epidemic, we may so locate our troops temporarily as to afford them the prospect of being beyond the geographical range, and hence out of the reach of cholera of a known provincial avoid
distribution.
appendix may be investigated, as far as the informadisposal will admit, the channel through which a cholera which invades Asiatic-Kussia, Arabia, or Europe, leaves Hindostan; the laws under which its exodus is effected; its probable distribution; the date of its renewal in each year subsequent to invasion; and the date at which its final cessation as an epidemic may be looked forward to. 6-?There is no narrow basis upon which this great study can be pursued. No local study of cholera, however carefully As an
tion at our
followed out, can ever lead to the determination of truths which shall be received as permanent. Cholera repeats its lesspns year after year, and, supplying us with precise
by
parallels, profess to
invites us to recognise their significance. I cannot have read aright the teachings of all these great facts ; nevertheless it is worth while to keep in view that the opportunity has never hitherto been given for the study of the on
subject scale, and with the same precision, for a series of years. And this fact, probably, rather than any difficultv or mystery connected with the subject, explains why a connected narrative of the history of our Indian cholera has never yet been written. I ask you, therefore, to investigate these questions with me, as presenting no difficulty which cannot be overcome by the exercise of our judgment on the collected evidence. 7.?I propose to arrange the propositions to be discussed somewhat in the following order :?
the same
[October 1,
(a.)?The geography
18G6.
of cholera in any year is definite and
be demonstrated.
can
(J.)?Certain
areas are
occupied by cholera
in each year, while
others are free from its presence.
Cc.)?Certain areas enjoy comparative exemption from cholera in every year ; in others it is endemic and perennial. (d.)?The area of this Presidency may be mapped out in two primary divisions, the endemic and epidemic regions of cholera ; the
epidemic area is essentially an invaded area. (e.)?The invaded area has a direct relation to cholera already existing beyond its boundary line; when the boundary is overstepped, an endemic cholera becomes epidemic and invading. Cholera, however, may become truly epidemic within its endemic area without the transgression of the endemic limits, but in this case invasion of the epidemic area is imminent within a limited period. (/.)?When cholera invades an unoccupied area, the source of invasion, and its direction are exhibited to us ; the geographical limit to which an invading cholera extends is also made
evident.
(
its
may meet with it. Genebal Definitions. A.?The train of symptoms called cholera is
we
the effect of
object, under whatever conditions it may be manifested; the object, the presence of which brings about these symptoms, has the value in a natural history system of a species. B.?Endemic cholera is the cholera of a distinctly defined geographical area, within which it is perennially existent. C.?Epidemic cholera is the cholera of all regions beyond the the action of
one
and the same
limits of the endemic area. An epidemic cholera originates
primarily within the endemic area, and the cholera of the epidemic area has separate aspects under two different conditions : the first is that of an invading cholera, shown while cholera is in course of distribution over definite portions of the epidemic area; the second is as a reproduced cholera, renewed over definite portions of the epidemic area in months or years subsequent to its original distribution. D.?AVithin the epidemic area, a cholera which has made its invasion necessarily dies out within a certain definite period (probably three years) ; and if cases of cholera come forward after the termination of this
period, they are generally isolated and may be regarded as indicative of the presence of a cholera whose vitality has become impaired, or of a cholera in an abortive state. usually fatal,
are not
systematise the entire series of phenomena, may at seem an impossibility ; but the sequence in which I propose to bring the various aspects of cholera before you, may help us, starting from a sure foundation, to add one series of truths to another, of which the sum total may serve to form the 1.
first
To
sight
basis of a system. 2. The facts and illustrations I must ask you to accept: as facts ; the hypotheses which I may adduce as deductions from the collected facts, I ask you to discuss with me, in order
that my interpretation of their significance may be tested by
judgment and experience. The general conclusion to which my study of the subject leads is this,?that there is nothing casual or fortuitous in the occurrence of cholera in any locality or at any season ; but that every epidemic, every outbreak, and indeed any case of cholera has a definite position in a grand system. 4. The special data from which the conclusions arrived at, are drawn, are the results of the experience of upwards of a hundred and fifty thousand individuals daily under European medical observation. The study has extended over a period of eleven year's, viz., from 1856 to the present date ; and the statistical results have been systematically arranged from the original official documents by my own hand. The above numbers iuclude the European Army in Bengal, averaging, with women and children, about 50,000 ; the Native Army, numbering about 60,000 ; and prisoners, averaging about 52,000 in each year.
your 3.
The area of observation extends from the Assam Frontier the East, to Nagpore and the Valley of the Nerbudda on the South and West, and from the North-Western Frontier to
on
the Bay of Bengal. This includes the countries
SUGGESTIONS FOR THE SYSTEMATIC STUDY OF THE HISTORY AND RELATIONS OF CHOLERA. By JAMES L. BIIYDEN, M.D., Assistant-Surgeon, Her Majesty's Bengal Army. I iiave been asked to indicate to
you*
the
general phenomena
exhibited by the Cholera of this Presidency, in connexion with * This Communication was originally read before ference at Simla.?Ed., I, M. O.
a
Professional Con-
31? North, and longitude 70? 5.
The
following
to
lying between latitude 20? to 96? .East.
is the order in which I wish to
various sections of my subject before you
bring
the
:?
geographical distribution of cholera I shall take the cholera of the twelve years 1855 to 1866 inclusive, and show what has been in each year the geographical distribution and limit of epidemic cholera, and A.?Phenomena of the
in this
Presidency.
define the areas which have been
those which have been exempted,
occupied
in each year, and
I shall try to show the
THE INDIAN MEDICAL GAZETTE.
284
laws of limitation, the laws of distribution, and the laws of exemption. B.?The phenomena of the invasion of an unoccupied area. This section will treat of the origin of an invading cholera, of the direction in which an epidemic cholera invades, and the relation which it bears to the agencies which control its progress. C.?"Will treat of the behaviour of sequent to its invasion of an epidemic
aspect of a reproduced cholera as
epidemic cholera subprovince ; and of the distinguished from a cholera in
actual course of distribution. Under this head will be discussed the
questions,?what pheno-
proper to cholera as an object of natural history ; at what seasons it shall come forward in epidemic or local manifestation, according to its geographical situation; and what
mena
are
agencies shall accelerate, or epidcmic spread.
and what shall retard its re-appearance
In this section the laws regulating the final decay and disappearance of epidemic cholera may also be treated of. D.?Here we may try to determine what amount of truth lies in the assertions, that cholera is propagated locally by to man, and is in this certain geographical area ; and that the
transmission of the miasm from manner
spread
over
a
man
cholera miasm may multiply itself within the human economy, finding there a suitable nidus for rapid propagation. The important questions?what conditions tend to bring about the localisation of cholera, and upon what rational grounds does the system of the avoidance of cholera by marching away from an affected locality rest, may here be taken up. of the history of the cholera of these twelve years with the history of cholera in the past, in order to determine how far the phenomena of cholera are permanent, and consequently under fixed laws; how far, E.?A
comparison
the
we
of
may anticipate past experience, cholera in any year, and in any localiwe may ty, before its actual invasion or outbreak; how
ground upon the occurrence of
march
troops in any province of this Presidency so as to cholera, the meeting with which is at present regarded as inevitable; and how, in anticipation of an approaching epidemic, we may so locate our troops temporarily as to afford them the prospect of being beyond the geographical range, and hence out of the reach of cholera of a known provincial avoid
distribution.
appendix may be investigated, as far as the informadisposal will admit, the channel through which a cholera which invades Asiatic-Kussia, Arabia, or Europe, leaves Hindostan; the laws under which its exodus is effected; its probable distribution; the date of its renewal in each year subsequent to invasion; and the date at which its final cessation as an epidemic may be looked forward to. 6-?There is no narrow basis upon which this great study can be pursued. No local study of cholera, however carefully As an
tion at our
followed out, can ever lead to the determination of truths which shall be received as permanent. Cholera repeats its lesspns year after year, and, supplying us with precise
by
parallels, profess to
invites us to recognise their significance. I cannot have read aright the teachings of all these great facts ; nevertheless it is worth while to keep in view that the opportunity has never hitherto been given for the study of the on
subject scale, and with the same precision, for a series of years. And this fact, probably, rather than any difficultv or mystery connected with the subject, explains why a connected narrative of the history of our Indian cholera has never yet been written. I ask you, therefore, to investigate these questions with me, as presenting no difficulty which cannot be overcome by the exercise of our judgment on the collected evidence. 7.?I propose to arrange the propositions to be discussed somewhat in the following order :?
the same
[October 1,
(a.)?The geography
18G6.
of cholera in any year is definite and
be demonstrated.
can
(J.)?Certain
areas are
occupied by cholera
in each year, while
others are free from its presence.
Cc.)?Certain areas enjoy comparative exemption from cholera in every year ; in others it is endemic and perennial. (d.)?The area of this Presidency may be mapped out in two primary divisions, the endemic and epidemic regions of cholera ; the
epidemic area is essentially an invaded area. (e.)?The invaded area has a direct relation to cholera already existing beyond its boundary line; when the boundary is overstepped, an endemic cholera becomes epidemic and invading. Cholera, however, may become truly epidemic within its endemic area without the transgression of the endemic limits, but in this case invasion of the epidemic area is imminent within a limited period. (/.)?When cholera invades an unoccupied area, the source of invasion, and its direction are exhibited to us ; the geographical limit to which an invading cholera extends is also made
evident.
(
