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EPIDEMICS
EXAMINED AND EXPLAINED:
OR,
LIVING GERMS
PROVED BY ANALOGY TO BE
A SOURCE OF DISEASE.
BY
JOHN GROVE, M.R.C.S.L.
AUTHOR OF "SULPHUR AS A REMEDY IN EPIDEMIC CHOLERA."
LONDON:
JAMES RIDGWAY, PICCADILLY.
MDCCCL.
* * * * *
"The tendencies of the mind, the turn of thought of whole ages, have
frequently depended on prevailing diseases; for nothing exercises a
more potent influence over man, either in disposing him to calmness and
submission, or in kindling in him the wildest passions, than the
proximity of inevitable and universal danger."--_Hecker's Epidemics of
the Middle Ages._
"The grand field of investigation lies immediately before us; we are
trampling every hour upon things which to the ignorant seem nothing but
dirt, but to the curious are precious as gold."--_Sewell on the
Cultivation of the Intellect._
* * * * *
TO
BENJAMIN GUY BABINGTON, F.R.S., M.D.,
PHYSICIAN TO GUY'S HOSPITAL,
AND
PRESIDENT OF THE EPIDEMIOLOGICAL SOCIETY,
ETC. ETC.
THESE PAGES ARE, BY HIS KIND PERMISSION,
Respectfully Dedicated,
BY HIS OBLIGED AND FAITHFUL SERVANT,
THE AUTHOR.
* * * * *
{v}
PREFACE.
The following pages have been written with a view to render some aid in
establishing a sound and firm basis for future research, on that absorbing
topic, the Causes and Nature of Epidemic Diseases.
The amount of information already published on Fevers, on the Exanthemata,
and on the Plague, is truly astonishing, and the more so when it is
considered, that at present no rational account or explanation is given of
the causes of these affections.
It appears to me but reasonable to suppose that as every thing on this
earth has been created on a wise and unerring principle, Epidemic and
Infectious Diseases are only indicative of some serious errors in our
social arrangements and habits. The dangers and misery brought upon us by
disease, may, as shewn by Dr. Spurzheim and Mr. Combe, be warnings against
the infringement of the natural laws.
Indeed, what is more rational than to suppose that the Seeds of Disease are
coeval with the fall of man. His first disobedience {vi} brought
death:--that his subsequent errors should hasten its approaches is not to
be marvelled at. The undetected murderer, though he may escape the
punishment human justice would inflict upon him for his delinquency,
suffers a penalty in the tortures of conscience, infinitely more horrifying
than the most ignominious death. The law of nature is triumphant.
No less certain, though after a different manner, are the consequences of
minor forms of disobedience. It is so ordained, that certain diseases shall
arise, under peculiar conditions, which may have been brought about by a
train of causes, easily imagined, and difficult to be explained, but all
having their origin in the vices and errors of man in his moral and social
relations.
If man neglects the cultivation of the ground; with rank vegetation, the
germs of fever will invisibly grow and multiply; if he harbours that which
is rotten and corrupt, he is himself consumed by those agents destined to
remove the rottenness and corruption; it is a part of the law of nature
that there should be active and energetic agents for this purpose. The
seeds of disease, like the seeds of plants, may be shewn to have {vii}
their indigenous localities; like them they may be spread and multiplied;
like them they may lie dormant, and after awhile spring as it were into
active existence; like them, when the soil and other conditions favour,
they are ever ready to make their appearance. And this is the law, the
germs of all disease exist, and have existed. Despise the dictates of
nature, be careless of yourself and those around you, neglect to use the
means which a noble intelligence has placed at your command, and above all,
transgress the laws of God, then will disease pursue and attend you, as the
conscience of the murderer pursues and attends him until he is finally cut
off.
His wants and necessities, his sufferings and privations, are the basis of
the intellectual progress of man. The wonders of Omnipotence are revealed
through the whirlwind, the storm, the pestilence, and the famine.
The constructive and perceptive faculties of man have been developed by the
necessity of protecting himself from injury by winds and rains; his
intellectual faculties have been cultivated, by the sufferings of disease
having led him to the study of {viii} organization and life, to discover
the cause,--and to chemistry, and other sciences for the cure of his
ailments.
Famine and distress have aroused his emotions, and softened down his
asperities, so that what appears at first to be the infliction of a Curse
without Pity, is in reality a Judgment with Mercy.
It occurred to me, that on the formation of the Epidemiological Society,
the first question for consideration should be, What is the nature of those
agents, which induce Epidemic Diseases? are they composed of animate or
inanimate matter? In other words, do the manifestations of these diseases
exhibit the operations of living or of chemical forces.
Having, in my study, dwelt on the subject with an earnest desire to find
the truth, I put the suggestion, with my ideas, before the public to reject
or receive them. If they be rejected, I can but think a full discussion of
the enquiry will lead to the most important results. If they be received
with favour, I doubt not others, with more ability, will take up the strain
and resolve the discords into harmony.
J. G.
_Wandsworth, September, 1850._
{ix}
CONTENTS.
PAGE
INTRODUCTION 1
CHAPTER I.
IS IT PROBABLE THAT EPIDEMIC, ENDEMIC, AND INFECTIOUS
DISEASES, DEPEND UPON VITAL GERMS
FOR THEIR MANIFESTATIONS? 11
CHAPTER II.
THE NUMBER AND VALUE OF FACTS TO SUPPORT
THE PROPOSITION.
SECTION I.--On Reproduction 22
SECTION II.--Historical Notice of Epidemic Diseases 34
SECTION III.--The Dispersion of Plants and Diseases 64
SECTION IV.--The Relation between Epidemic and Endemic
Diseases 96
CHAPTER III.
THE REASONABLENESS OF THE APPLICATION OF
THE FACTS TO THE INFERENCE.
SECTION I.--The Chemical Theory of Epidemics untenable 108
SECTION II.--The Animalcular Theory of Epidemics untenable 128
SECTION III.--Sketch of the Physiology and Pathology of
Plants and Animals 138
CHAPTER IV.
RESULTS IN PROOF OF THE TENABLENESS OF THE
PROPOSITION.
SECTION I.--Observations on some of the Laws of Epidemic
Diseases 155
SECTION II.--What is the nature of those Poisons which most
resemble the Morbid Poisons in their effects on the body? 166
SECTION III.--What results do we obtain from the effects of
remedial agents, in proof of the hypothesis? 176
CONCLUSION 189
* * * * *
{1}
INTRODUCTION.
It is one thing for a man to convince himself, but a very different thing
to be able to convince others.
I am not now speaking of a conviction arising from the impression made by a
few startling facts, nor of one forced on the mind by early prejudices, or
by the dogmas of the schools, but of a conviction arising from careful
enquiry.
In the course of that enquiry, the collector of facts, sees their relations
to the idea in his mind, in a multiplicity of ways, from their remaining,
each, as one succeeds the other, an appreciable time on the sensorium, and
undergoing a certain process of comparison and relation, with all other
facts and ideas which have been previously stored up. As the materials for
an edifice which have been shaped and prepared in accordance with the
completion of the design, so do the facts and ideas which are accumulated
{2} in the mind, become shaped and prepared for the elimination of a truth.
The ultimate design of the architect can no more be conceived by the
examination of the framework of a window, or the capital of a column, than
the whole truth of a proposition by the examination of separate facts; the
whole must be conceived and all the relations of all the parts thoroughly
understood, before the architect can be comprehended or the harmony of his
design appreciated.
The process of thought in the minds of the architect, and in the framer of
a proposition, is never exactly the same as in those who contemplate and
examine their completed works. Much may be done, however, by both to aid
others in comprehending them. The more accurately they keep in view the
course their minds have taken, the more readily will their descriptions be
understood.
To simplify the elements of our knowledge is to give others a ready access
to our thoughts.
To arrange the course of our ideas in harmony with the elements of our
knowledge should be the end of all writing, as it is the only means of
multiplying knowledge. {3}
It is not the mere accumulation of facts which constitutes science, any
more than a collection of building materials constitutes a house, it is the
arrangement and adaptation of the means to the end by which the house
becomes built and science cultivated.
These reflections have been suggested by the circumstance that for the last
3000 years and upwards, Pestilences have at certain intervals done their
work of destruction, and opened the springs of misery to untold millions,
and yet I see not that we are much further advanced as to the knowledge of
the cause of these inflictions than the Jews in the time of Moses. In the
Levitical law, as I shall have occasion more particularly to shew
hereafter, were directions specially given in reference to the plague of
leprosy; what means should be adopted for the cure of the disease, and for
preventing its extension, and moreover pointing very significantly to
certain facts having connexion with the cause of the affection. Since that
time historians generally, and medical writers in particular, have
diligently recorded their observations and accumulated facts, on the
various desolating plagues which {4} have afflicted mankind. Some of these
men have grappled with the whole subject, and endeavoured to shew the
presumed relation of the supposed causes in all their intricacies, but it
is hardly necessary to say that all have signally failed in their attempts
to furnish us with any practical information.
Satisfied in my own mind that the whole subject is beyond the labour of one
man, and impressed with the belief that the basis of the enquiry is in
anything but a satisfactory state, I have applied myself entirely to the
study of the groundwork only, as the primary proceeding for a solid
superstructure.
The days are past, when imaginary spirits, ethers, and astronomical
phenomena, were believed to have any essential influence over our destinies
in a physical point of view; we have therefore to deal with _matter_ in
some form or other.
The question, therefore, which I have proposed for enquiry, is, whether the
matter which causes epidemic and endemic diseases, exhibits the properties
of inorganic or organized matter.
The properties and qualities of organized {5} bodies, as well as those of
inorganic matter, need but be stated, and in some instances we may picture
to ourselves the object, without having seen it, and not be very far from a
true conception. But for this purpose a clear and definite idea must be
previously formed, and have taken possession of the mind, of the great
general divisions of objects in the material world.
Having made these preliminary remarks, I have suggested a certain mode of
procedure in making enquiries of this kind, not perhaps in strict
accordance with logical systems, but on the principle of nature's
operations in our own minds, which appears to me, when reduced to a
systematic and simple form, to be sufficiently clear and strict for
synthetical application, and so concise as to be usefully and practicably
applied.
In endeavouring to establish a theory for the explanation of extraordinary
phenomena, there are certain rules which should guide us in the thorny and
treacherous path of speculation. But these rules readily flow from the
train of thought, and if we examine our own minds during their operations,
we {6} shall find that the following is the course of our instinctive
reflections. It is a course we adopt as the test of theories when formed,
and is a guide in all cases for their construction.
We first commence with an idea, which exists in our minds in the form of a
proposition: then the following rules naturally suggest themselves:--
1. The probability of the value of our proposition from inference.
2. The number and value of facts to support the proposition.
3. The reasonableness of the application of the facts to the inference.
4. What amount of information in the form of results can be produced in
proof of the tenableness of the proposition.[1]
In illustration of the value of these rules the history of Dr. Jenner's
discovery affords an appropriate example. To use the words of Dr. Gregory,
"he appears very early in {7} life to have had his attention fixed by a
popular notion among the peasantry of Gloucestershire, of the existence of
an affection in the cow, supposed to afford security against the Small Pox;
but he was not successful in convincing his professional brethren of the
importance of the _idea_."
The popular notion of the peasantry originated the idea in Jenner's mind,
and it became fixed there as a proposition.
1. He commenced his enquiry by observing that the hands of milkers on the
dairy farms were subject to an eruption, and he _inferred_ that the notion
of the peasantry bore the stamp of probability, which strengthened the idea
in his mind and gave force to the proposition.
2. His next step was to accumulate facts; he found on enquiry that the
persons engaged on these farms in milking, possessed an immunity from Small
Pox to an extent sufficient to strengthen the value of his proposition.
3. The reasonableness of the application of the facts to the inference is
clear from the coincidence that the eruption on the hands of the dairy
people bore a striking {8} resemblance to the Small Pox, and as this
disease does not usually occur twice in the same individual, the inference
was most reasonable that this eruption protected the people from Small Pox.
4. We have but to take the almost universal adoption of vaccination, and
its acknowledged prophylactic powers against the propagation of Small Pox
to shew the application of our fourth rule.[2]
Between the conception of the idea and the accomplishment of Jenner's
designs, vaccination seems to have undergone an incubation of nearly twenty
years. During that period, with an energy and perseverance only to be
obtained by confidence, did this great man brood over and elaborate his
idea; and well might the 14th day of May, {9} 1796, be styled the birth day
of vaccination, for on that day was a child first inoculated from the hands
of a milker.
In adopting the above method I have endeavoured to bear in mind M.
Quetelet's observations on the requirements necessary for medical
authorship; he says, "All reasonable men will, I think, agree on this
point, that we must inform ourselves by observation, collect well-recorded
facts, render them rigorously comparable, before seeking to discuss them
with a view of declaring their relations, and methodically proceeding to
the appreciation of causes."
* * * * *
{10}
{11}
CHAPTER I.
IS IT PROBABLE THAT EPIDEMIC, ENDEMIC, AND INFECTIOUS DISEASES, DEPEND UPON
VITAL GERMS FOR THEIR MANIFESTATIONS?
It is, I believe, almost universally considered that Epidemic, Endemic, and
Infectious diseases, originate from some imaginary poisons of a specific
nature, each disease having its own peculiar poison. That this conception
should have taken possession of the minds of men, is most natural from the
symptoms which characterize these diseases, but when we come to enquire
into the nature of these agents, or supposed poisons, we are at once struck
with the idea that they exhibit one peculiarity which separates them in a
marked manner, from those poisons with which we are familiar; for the
poisons of Small Pox, Measles, Scarlet Fever, Hooping Cough, Fever, &c.
possess the power of multiplication, or spontaneous increase, a property
which attaches only to the organic kingdom, and is never known in the
inorganic kingdom. The source of most of the poisons is to be found among
mineral or vegetable products. A mineral in combination with an acid or
oxygen may become a poison, and {12} nitrogen in various combinations with
oxygen, hydrogen, and carbon, or with carbon alone, may become a poison;
these combinations are, however, in most instances the products of
vegetable life, others again are obtained from the animal kingdom, such as
the poison of the serpent, &c. but in all of these instances, there is not
one in which the power of self-multiplication is to be found.
We are, therefore, constrained to admit that this feature, which
distinguishes poisons, is one well worthy attentive consideration. The
varieties of poisons may be classified into those which act topically as
escharotic poisons, those which act chemically on the blood, and those
whose effects are manifested in inducing a speedy annihilation of organic
or vital action, as in the case of hydrocyanic acid, which is supposed
specifically to affect the nervous centres from which originate the vital
manifestations. It is rather remarkable that the vital poisons (as I will
call them for distinction), seem to have their appropriate locality in the
blood, they do not primarily affect one organ more than another, all the
effects we witness resulting from them are to be traced progressively from
the blood to other parts of the body. When a person is inoculated with
small pox, a very minute portion (indeed it is impossible to say how minute
it may be) is sufficient, when absorbed, to excite a certain train of
symptoms, all due to absorption of the materies of the disease, and the
process by which {13} that materies arrives at maturity, is that known in
the vegetable world as the fructification; this process of fructification
is a process of development and increase.
I here may repeat that among all the poisons known, constituted as they are
of various combinations of elementary matter, they are without exception
destitute of the power of development or increase. Now, it is pretty
accurately known what amount of these poisons is necessary to produce their
effects on the living body; we can say how many drops are sufficient of
hydrocyanic acid of Scheeles strength, to destroy a man instantaneously.
Again, how many grains of arsenious acid are sufficient to induce such an
inflammatory condition of the stomach and intestine as will end in death,
and how many grains of morphia, will bring about a fatal coma,--but who
shall say the amount of the vital poisons necessary to produce their
results? It far exceeds the limit of conjecture, to what extent the
dilution of miasmatic or contagious matter may be carried, and the poison
yet be capable of committing in a short time the most frightful ravages.
We may fairly then infer, that if a quantity of matter inappreciable in
amount be sufficient to exhibit the characters of growth and increase, that
it is endowed with the properties of vitality. That the poisons of scarlet
fever, of measles, and of small-pox have this power of growth and increase,
is as much a matter of universal belief as that "the sun {14} will rise and
set to-morrow, and that all living beings will die."
This power of individual increase, or reproduction, is the very summit of
vital manifestation; indeed Coleridge, in his Theory of Life, (in which he
says, "I define life as the _principle of individuation_, or the power
which unites a given _all_ into a whole that is presupposed by all its
parts,") places reproduction in the first rank, and expresses his
hypothesis thus: "the constituent forces of life in the human living body
are, first, the power of length or reproduction; 2nd, the power of surface,
or irritability; 3rd, the power of depth, or sensibility--life itself is
neither of these separately, but the copula of all three."
Extensive research is not required to shew that many thinking men believe
in the existence of living organic beings, as the elements of contagious
and epidemic diseases; the idea indeed seems to flow spontaneously in that
direction. Whenever thought, and enduring contemplation, have been
concentrated on the subject, the result appears to have been the same, a
firm conviction in each individual mind that a vital force must be in
operation; or as Schlegel would define it, "a living reproductive power,
capable of and designed to develope and propagate itself."--"Its Maker
originally fixed and assigned to it the end towards which all its efforts
were ultimately to be directed."
Referring further to beings having the property of reproduction and
propagation, he says, (using {15} the word nature here evidently as the
vital principle for want of a better term,) "Nature indeed is not free like
man, but still is not a piece of dead clockwork. _There is life in
it._"--"Thus we know that even plants sleep, and that they too as much as
animals, though after a different sort, have a true impregnation and
propagation."
When Schlegel wrote this, how little could he have imagined the intricacy
of this proceeding among the lower forms of vegetation. It has been shewn
by Suminski, and verified by many others, that the mode of impregnation,
and the period at which it occurs in the ferns, do not at all correspond to
the general notion on this subject. He has discovered in the early
development of the frond of ferns certain cells, which he denominates
antheridia, or sperm cells; these contain in their cavity a number of
subordinate cells, each containing a spermatazoon. At a certain period of
the progress of the frond, the parent cells become ruptured and liberate
the spermatoza, these move about in a mucilaginous fluid, which bedews the
inferior surface of the frond, and become the means of impregnating the
germ cells, or pistillidia, with which they readily come in contact. Thus
the process of impregnation in these plants occurs during the germination,
or what corresponds to the period of germination in the seeds of exogenous
and endogenous plants.
I have referred to the discovery of Suminski in {16} this place to recal to
the mind the great and incomprehensible wonders of creation, for who could
conceive it possible or feasible that even for the impregnation of an
inferior vegetable, animal life should form an indispensable and essential
appurtenant of the process. Truly may we say with Coleridge, of plants and
insects, "so reciprocally inter-dependent and necessary are they to each
other, that we can almost as little think of vegetation without insects, as
of insects without vegetation."
I will make but two more quotations on the supposed vital character of the
germs of disease. "That the air and atmosphere of our globe is in the
highest degree full of life, I may, I think, take here for granted, and
generally admitted. It is, however, of a mixed kind and quality, combining
the refreshing breath of spring with the parching simooms of the desert,
and where the healthy odours fluctuate in chaotic struggle with the most
deadly vapours. What else in general _is the wide-spread and spreading
pestilence_, but a living propagation of foulness, corruption, and death?
Are not many poisons, _especially animal poisons, in a true sense, living
forces_?"--Schlegel.[3]
It were useless to multiply quotations to shew {17} that the opinions here
entertained are matters of general belief among thinking men.[4] I will at
once then conclude with an observation of Dr. C. J. B. Williams: he puts
the question, "Does the matter of contagion consist of vegetable seeds? Are
infectious diseases the results of the operations and invasions of living
parasites, disturbing in sundry ways the structures and functions of the
body, each after its own kind, until the vital powers either fail or
succeed in expelling the invading tribes from the system?"
And this expression, the seeds, is an universal expression, it is a
"Household Word" in connexion with disease. That it has obtained this
position in the popular vocabulary is alone a proof of the applicability of
the term to the thing intended to be {18} signified. Popular notions, as we
have seen in the case of Jenner's discovery, are not to be unheeded. An
instance occurs to me, it was a popular belief, that in acne punctata, the
matter of a sebaceous follicle, was itself, when pressed out, a worm, the
dark portion which results from the accumulation of dust upon the matter at
the mouth of the follicle was supposed to be the head of the maggot, as it
was called; subsequent observation, however, has proved that though this
matter is not a worm, it contains an animal within its substance, the
Acarus folliculorum.
The popular notions found among savage tribes as to the efficacy of certain
remedies in the cure of disease have been the means of furnishing us with
some of our most valuable medicines, indeed it is almost impossible to say
whether originally man did not derive his remedies from the herbs and trees
by an instinctive faculty impelling him, as it does the animals when in a
state of liberty and with freedom of range, to seek certain plants as they
avoid others.
It is well known that animals when indisposed will find out some spot as if
almost led to it by a visionary guide where the "healing plant" is to be
discovered. I am told that sheep have this faculty, and that they will,
when affected with the rot, feed upon some plant when they can discover it,
which eradicates the disease.
Almost every one is familiar with the fact that cats and dogs will crop
herbage and eat it; I have {19} seen them frequently leave the house and
proceed to the grass in the most business-like manner, partake of some
quantity, and quietly return.
A close observer of diseased animals might obtain some useful information
by noticing the plants cropped by them while in that condition. The
observations should be made in a variety of districts in consequence of the
uncertain distribution of some even of the most commonly scattered plants;
in one year they may be abundant, but in another they may be almost
entirely absent from the same spot.[5]
Were it only on the fact of reproduction, I would be contented to take my
stand that the force of life is the indwelling power of pestilential
matter. Reproduction is a law of nature, and the law of nature is the law
of God. And where do we find He prevaricates with us? The more we study His
laws the more harmony and perfection we find; what is seeming confusion in
the ignorance of to-day, is order in the knowledge of to-morrow. If any one
ignorant of the law which regulates the diffusion of gases were {20} told
that a heavier gas would ascend contrary to its specific gravity through
the septum in a vessel containing a lighter gas above the heavier, he would
naturally doubt your assertion, and say, "that is contrary to the law of
gravity;" but explain to him the principle by which this comes about, and
the objects of the law; the order and beauty of the design become manifest.
But this is no equivocation, it is evidence there, that subordinate laws
exist and nothing more. It has never been found that men have gathered
"grapes of thorns and figs of thistles," nor has it ever been discovered
that inanimate matter multiplies itself. The seed of disease "is within
itself," multiplying and propagating itself; whether it formed a part of
creation at the beginning or not, is rather a question to be solved by
divines than physicians. When we know, however, the latency of seeds and
even of entire plants, and that they may be dried and remain so for years
yet being brought again into conditions adapted to their active existence,
they, as it were, revive from their sleep, and renew again their
reproductive properties: can we wonder if, in the great scheme of nature,
existences new to mankind should make their appearance? When the New
Zealander saw the surface of his ground producing to him unknown plants,
and the skins of his children generating peculiar eruptions, and each
propagating its kind, would he look, think you, to the wood or the stones,
the air or the water,--for the solution of the {21} mystery? No, he would
naturally say these people brought the _seeds_ with them. From the property
of reproduction possessed by these forms of matter, we infer the value of
the proposition.
* * * * *
{22}
CHAPTER II.
THE NUMBER AND VALUE OF FACTS TO SUPPORT THE PROPOSITION.
--------
SECTION I.
ON REPRODUCTION.
It is inferred that the proposition, "_the matter which operates in the
production of Epidemic, Endemic, and Infectious Diseases, possesses the
property of vitality_," we proceed now to the enumeration of those facts
which further elucidate this subject.
The facts must necessarily be such as illustrate the identity of properties
in the imaginary germs, that are known to exist in demonstrable germs: we
take therefore the law of reproduction to be to life, what the law of
attraction is to gravitation.[6]
{23}
But further; do those matters which engender disease furnish to our minds
the properties inseparable from life in the abstract? Though the faculty of
reproduction is essentially an evidence that the thing which reproduces its
kind must be a living body, yet it is only a property or power of living
beings and is not itself life, it therefore is necessary to establish the
fact that the _materies morbi_ not only has the power of reproduction, but
also those properties which in the abstract will prove as far as
demonstration can go, that it has the essential properties common to all
living bodies.
I must again quote from Coleridge, he says: "By life I every where mean the
true idea of life, or that most general form under which life manifests
itself to us, which includes all its other forms. This I have stated to be
the _tendency to individuation_ and the degrees or intensities of life, to
consist in the progressive realization of this tendency. The {24} power
which is acknowledged to exist wherever the realization is found, must
subsist wherever the tendency is manifested. The power which comes forth
and stirs abroad in the bird, must be latent in the egg."
The tendency to individuation cannot be more strongly marked than in the
simple experiment of vaccination: we insert a small particle of the
so-called vaccine lymph under the skin, and by this means we multiply to an
enormous extent, the power which, in the first instance, we had in the form
of minute corpuscles in a dry and apparently inert state; nevertheless,
though in this condition there must have existed the tendency to
individuation or multiplication of individual existence, and the germs are
here to their active existence, as seen in the development of the vaccine
vesicle, what the egg is to the bird,[7] as described above; we may,
therefore, say that the power which exhibits itself in the production of a
vaccine vesicle, must have been latent in the dried matter. It is the
opinion of Muller that the entire vital principle of the egg {25} resides
in the germinal disk alone, and since _the external influences which act on
the germs_ of the most different organic beings are the same, we must
regard the simple germinal disk, consisting of granular amorphous matter,
as the potential whole of the future animal, endowed with the essential and
specific force or principle of the future being, and capable of increasing
the very small amount of this specific force and matter, which it already
possesses, by the assimilation of new matter.
After speaking of inanimate objects, Dr. Carpenter says; "and what compared
with the permanence of these is the duration of any structure subject to
the conditions of _vitality_? _To be born_, to grow, to arrive at maturity,
to decline, to die, to decay, is the sum of the history of every being that
lives; from man, in the pomp of royalty, or the pride of philosophy, to the
gay and thoughtless insect that glitters for a few hours in the sunbeam and
is seen no more; from the stately oak, the monarch of the forest through
successive centuries, to the humble fungus which shoots forth and withers
in a day."
To be born, signifies the faculty of reproduction existing or having
existed in an antecedent being to that one born, and also that itself
possesses equally a like power. To be born, is the first expression which
must be used in speaking of the faculties or properties of living beings as
independent existences, the annual formation of buds, trees, and shrubs, is
a multiplication of the species; the coral {26} and various budding polypes
increase by this process, indeed what is the seed of a plant, or the egg of
a bird, or the ovum of mammalia, but cast off buds; in all, the new being
was originally a portion of its parent, and if we examine the ovary of the
vegetable, the bird, or the mammal, can we find any expression more fitting
to designate the process than that of budding. To be born then, is the
evidence of an act of one living being, and the commencement of a series of
vital phenomena in another, but all these are subsequent to reproduction,
and constitute another chain of vital acts, all tending to a similar
result, the multiplication of the species.[8]
Now, whether we apply the philosophical language of Coleridge, or the
language of observation of Muller, in confirmation of the doctrine here
inculcated, we arrive at the same point.
Do we not witness in the newly formed vaccine vesicle, an increase of the
specific force and principle? We certainly have acquired by the process of
vaccination a manifold multiplication of power, and is there not also
assimilation of new matter in {27} which this power resides? And does not
every particle of this new matter contain within itself the same force and
principle, as existed in that which generated it?
"We revert again to potentiated length in the power of magnetism
(reproduction); to surface in the power of electricity, and to the
synthesis of both or potentiated depth in constructive, that is chemical
affinity."[9]
Some may be at a loss to conceive, at first, how irritability may be
considered a property of all vegetable matter; that it does exist in some
vegetables is certain, but that it does exist in all living beings is
equally certain;[10] the term, however, which would appear more appropriate
when that irritability does not exhibit itself in an appreciable form, is
_impressibility_. Irritability, as commonly understood, is seen in its
highest condition in muscular tissue; but "the irritable power and an
analogon of voluntary motion first dawn on us in the vegetable world in the
stamina and anthers at the period of {28} impregnation."--"The insect world
is the exponent of irritability, as the vegetable is of reproduction."
The property of irritability attains its acme in man, the most highly
organized of all beings; and its gradations pass downwards through the
whole scale of animate creation; not so reproduction, for this faculty
observes the very opposite direction, for in plants a single impregnation
is sufficient for the evolution of myriads of detached lives.
Reproduction is a fact, it is an essential property of life, and is a
reality to us from observation; but irritability is not so tangible and
demonstrable a property. We nevertheless may assume its universality, from
the circumstance that we lose sight of it by imperceptible degrees; the
irritability of the sensitive plant is as much irritability as that of the
highly organized muscle; but because the faculty evades our perception, "in
tapering by degrees, becoming beautifully less," we have no reason for
pronouncing its total extinction at any one point of the vegetable
kingdom,[11] any more than we should have {29} in saying that we see the
end of the earth, when describing the extent of our vision as we stand on
the sea shore. The extreme limit of our vision is the tangent of the circle
in reference to our visual organs; but how many tangential points there may
be beyond, it is impossible to say without knowing the dimensions of the
circle.
I think we are now in a condition to assume, as far as abstraction will
conduct us without proceeding to an extreme length, that the _materies
morbi_, or, as I will now call them for the sake of clearer distinction,
_semina morbi_, possess those properties which in the abstract are common
to all living beings.
Another argument strikes me as capable of adding further strength to the
proposition. We need but be told that a small piece of iron was placed in a
certain position with regard to another piece of iron, and that the smaller
piece moved through a given space and became attached to the larger, to
infer that magnetic force was in operation. Supposing this magnet then to
be folded in paper, and that it {30} be promiscuously placed near a
compass, the deflection of the needle would indicate that some object in
the vicinity was the cause of the deflection; we may farther try what
positions the needle takes by varying the position of the packet, and thus
point out which is the north and which the south pole of the screw of
paper. If we may consider attraction then to be to gravitation what
reproduction is to life, we do not err in saying in the one instance that
there is a living being, and in the other there is a magnet.
The nebular theory, from which some astronomers made the foundation of many
speculations, came with so much interest to our minds that the fascination
could not be resisted. It was most delightful to revel in the imagination
that we possessed a key to the mode of formation of the starry hosts, and
when speculation had taken its extreme limits in the "Vestiges of the
Natural History of Creation," and the nebulae had served as the ground work
of a gigantic scheme, Lord Ross's monster telescope swept the heavens of
its cobwebs. We can imagine this great promoter of science saying to us,
Gentlemen, the clouds which have obscured you, are composed of myriads of
stars, and comprise systems as vast and as luminous as our own, had you but
power of vision to discern them. A new light thus appeared to philosophers,
and though no great practical results may flow from the discovery, it is
instructive from the fact that the imperfectly aided or unaided vision,
should not limit legitimate {31} inference. The nebulae before Lord Ross's
discovery were to the astronomer what the materies of epidemic and
infectious disease are to medical men. In the absence however of a giant
microscope to reveal such great truths, we may yet dimly shadow them by the
light of our reason. It was predicted in 1849 that minute vegetable germs,
in all probability all of the same type, were the agents producing epidemic
and infectious disease. In 1850, Mr. Oke Spooner says,[12] "On examining
the matter of Small {32} Pox and Cow Pox in every stage, he finds its
essential character to consist of a number of minute cells not exceeding
the 10,000th part of an inch in diameter: being about one-fourth smaller
than the globules of the blood, containing within their circumference many
still more minute nuclei, and presenting beyond their circumference
bud-like cells of the same size and character as those contained within the
circle."
Should these observations made by Mr. Spooner turn out to be correct, they
will but fulfil my anticipations. Then again shall we see the same
application of imperfect vision to the limitation or temporary obstruction
of solid and determinate knowledge.
We may reasonably expect that these bodies, discovered by Mr. Spooner,
should be the elementary matters of disease. Their existence was predicted
from the probability that living matter must be the agent; moreover, that
this matter when discovered {33} would be cellular, most probably
resembling the yeast plant as described by Mr. Spooner.
It was predicted that a planet would be discovered in a certain position in
the heavens, because the perturbations of a comet indicated an attracting
body in the path of the eccentric wanderer; the prediction and the
fulfilment were almost simultaneous.
* * * * *
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