GIFT OF
A- oe4:
MOLOfl
LIBRARY
/ 1 4^£sC<Xsts
BACTERIA.
BY
GEORGE M. STERNBERG, M.D., F.R.M.S.,
MAJOR AND SURGEON 0. S. ARMY ; MEMBER OP THE BIOLOGICAL SOCIETY OF WASHINGTON ;
LATE MEMBER OP THE HAVANA YELLOW FEVER COMMISSION OF THE NATIONAL BOA&D
OF HEALTH; CORRESPONDING MEMBER OF THE EPIDEMIOLOGICAL
SOCIETY OF LONDON ; ETC.
Enclutung One J^untiretJ anfc JFift2=tfcj0
FROM
THE WORK OF DR. ANTOINE MAGNIN,
TRANSLATED FROM THE FRENCH IN 1880.
ILLUSTRATED BY PHOTO-MICROGRAPHS, ETC.
Jen Plates and Twenty-nine Cuts,
SECOND EDITION.
NEW YORK:
WILLIAM WOOD AND COMPANY,
66 AND 58 LAFAYETTE PLACE.
1884.
Copyright, 1880,
BY GEORGE M. STERNBERG.
Copyright, 1888,
BY GEORGE M. STERNBERG.
fliULUCiY
LIBRARY
I-IMNTED BY JOHN WILSON AND SON,
IMVERSITY PRESS.
PREFACE TO SECOND EDITION.
THE First Edition of " Bacteria " being nearly ex-
hausted at the end of six months from date of publica-
tion, the writer has taken advantage of the opportunity
which this favorable reception of the work hac given
him, and has revised and added to the text, with a view
to making it still more worthy of a place in the libraries
of physicians, and of others interested in this important
field of investigation. Several of the plates have also
been remodelled, and new photo-micrographs introduced
in place of some of those in the first edition, which have
been excelled by later efforts. The bibliography has
also been brought up to date.
It has been thought best in the present edition to
remove the name of Dr. Magnin from the foremost
place upon the titlepage, inasmuch as the present writer
has contributed more than two-thirds of the text, and as
the illustrations from nature — photo-micrographs — are
all his work. The appreciation in which Dr. Magnin's
systematic account of the bacteria is held is shown,
however, by the fact that we have not attempted to
re-write this portion of the work, at the head of which
a separate titlepage, bearing Dr. Magnin's name, will
be found.
JOHNS HOPKINS UNIVERSITY,
BALTIMORE, MD., July 28, 1884. «
M123312
PREFACE.
THE work of Dr. Magnin, which was published in
Paris in 1878 and translated by the writer in 1880,
gave an admirable resume of our knowledge of the Bac-
teria at the date of its publication. But very consid-
erable progress has been made since, especially as
regards methods of manipulation, the comparative value
of various chemical reagents as " germicides " and anti-
septics, and the role of the Bacteria in infectious dis-
eases. With a view to keeping the work fully up to
the progress of science in' this direction, the writer
has added a chapter upon each of these subjects,
and one upon " Bacteria in Surgical Lesions " (Parts
Third, Fourth, Fifth, and Sixth). His name, therefore,
appears upon the titlepage as one of the authors of the
present volume. It has not been considered necessary,
however, to rewrite the chapters on Morphology and
Physiology (Parts First and Second). It is true that
the classification of Cohn, which was very properly
adopted by Professor Magnin, is only provisional, and
that certain recently discovered pathogenic species are
not included. But these will receive attention in Part
Fifth of the present volume ; and it would be pre-
mature to attempt a natural and permanent classifica-
tion of these minute plants, which are now engaging
the attention of numerous investigators* in all parts of
VI PREFACE.
the civilized world. For the present we probably can-
not do better than to adhere to the artificial classifica-
tion, based upon morphological characters alone, which
Cohn has given us.
It must be remembered, however, that SPHERO-
BACTERIA — micrococci — are not always round; that
there is no well-defined line of demarcation between
the MICRO-BACTERIA and the DESMO-BACTERIA, between
the genus BACTERIUM and the genus BACILLUS, or be-
tween the last-named genus and the LEPTOTHRIX.
The systematic naturalist, in his attempt to establish
genera and species among these lowly organisms, meets
with difficulties even greater than those encountered in
the classification of the higher cryptogams and flower-
ing plants. These difficulties arise from the multitude
of species and minute size of the unicellular organisms
under consideration ; from the various phases which
the same species may present at different epochs in
the life-history of the plant ; from the morphological
identity of species having different physiological char-
acters ; and, finally, from the influence of the environ-
ment in modifying both morphological and physiological
characters.
Most writers continue to speak of the Bacteria as
fungi. The observations of the writer are, however,
in favor of the view of Cohn, that they are more nearly
related to the algae. It would be idle, however, to
discuss this question, as the border-line of these two
great classes of the VEGETABLE KINGDOM is not well
defined ; and here, as in the attempt to establish gen-
era and species, the systematic naturalist must ever
encounter the stubborn fact that NATURE is contin-
uous, and, consequently, that ell attempts at classifi-
cation are artificial.
The writer ventures to hope that the rtsumt given in
the present volume will be found to fairly represent the
PREFACE. vii
present state of science as regards the minute organ-
isms of which it treats. No doubt the book contains
much that will not bear rigid scientific crijticism ; and
the constant additions to our knowledge which are
daily being made will necessitate frequent revisions and
additions, if a favorable reception by the Medical Pro-
fession, and students of Biology, makes it practicable
for the writer to carry out his present intention of rep-
resenting in future editions the progress which may be
made in the interval. I am not prepared to say, how-
ever, that the heliotype plates which illustrate this
edition will appear in subsequent editions, if they are
called for. These plates add greatly to the cost of the
volume, and they will perhaps be less satisfactory than
lithographs or wood-cuts to those not accustomed to
similar views under the microscope, and to those critics
who are not familiar with the technical difficulties
attending an attempt to photograph the minute organ-
isms here represented. If the clean field and sharply-
drawn outlines which it is so easy to draw upon wood
or stone makes a prettier picture, and one which may
be preferred by some, there can be no doubt that these
views from nature, if closely studied, are more instruc-
tive than drawings, notwithstanding the inevitable de-
fects arising in some instances from the presence in the
field of view of extraneous objects, and from the im-
possibility of having every part of the field in the best
possible focus at the same time in these photo-micro-
graphs, which are made with objectives of high power
having an extremely limited focal range.
G. M. S.
FORT MASON, SAN FRANCISCO,
August 15, 1883.
TABLE OF CONTENTS.
PAGE
INTRODUCTION 11
HISTORICAL . 13
PART FIRST.
MORPHOLOGY OF THE BACTERIA.
CHAPTER I. — ORGANIZATION.
1. — OF THE BACTERIA IN GENERAL 28
Forms 28
Dimensions 29
Colors 31
Movements 32
Structure 35
Cell-Membrane 35
Protoplasm 36
Cilia 39
2. — DIFFERENT MODES OF ASSOCIATION 43
Form of Little Chain (Torula) . 43
Form of Zooyl&a 44
Form of Mycoderma, &c 45
CHAPTER II. — CLASSIFICATION AND DESCRIPTION.
1. — PLACE OF THE BACTERIA 48
Among Organized Beings 53
In the Vegetable Kingdom 55
2. — CLASSIFICATION 59
Characters Generic and Specific 60
Classification of Cohn . . 65
TABLE OF CONTENTS.
PAGE
3. — DESCRIPTION OF GENERA AND SPECIES .... 65
Spherobacteria 71
Micrococcus 72
Monads 78
Microbacteria 80
Bacterium 80
Desmobacteria 86
Bacillus 87
Leptothrix 90
Spirobacteria 91
Vibrio 92
Spirillum 94
PART SECOND.
PHYSIOLOGY OF THE BACTERIA.
CHAPTER I. — DEVELOPMENT IN GENERAL.
§' 1. — ORIGIN OF BACTERIA 101
Heterogenesis 102
Dissemination 103
In Air 103
In Water 106
In the Human Organism 107
§2. — NUTRITION AND RESPIRATION Ill
Aliments : Water Ill
Nitrogen 112
Carbon 113
Oxygen 115
Temperature 118
Other Agents 121
§ 3. — REPRODUCTION 123
Fission 123
Spores 126
Sjiorangia 130
Polymorphism 133
TABLE OF CONTENTS. XI
CHAPTER II. — DEVELOPMENT IN DIFFERENT MEDIA.
PAGE
§ 1. — ROLE OF BACTERIA IN FERMENTATIONS .... 137
Acetic Fermentation 139
Arnmoniacal Fermentation 142
Lactic and Butyric Fermentation 144
§ 2. — ROLE IN PUTREFACTION AND NITRIFICATION . . 148
PART THIRD.
TECHNOLOGY.
§ 1. — METHODS OF CULTIVATION 156
Methods of obtaining Pure Stock 156
Natural Culture-Fluids 161
Blood 161
Milk* 163
Urine 164
Aqueous Humor 165
Artificial Culture-Fluids 167
Sterilization of Culture-Fluids 168
Culture Tubes and Flasks 171
Culture Flasks used by the Author 175
Culture Oven 180
Thermostat for Gas 181
§ 2. — THE RECOGNITION OF BACTERIA 184
§ 3. — STAINING BACTERIA 186
Staining the Tubercle Bacillus 190
Baumgarten's Method 191
Ehrlich's Method 191
Gibbs' Method 192
§ 4. — PHOTOGRAPHING BACTERIA 194
§ 5. — COLLECTION OF ATMOSPHERIC BACTERIA .... 197
Examination of Water 201
§ 6. — ATTENUATION OF VIRUS 201
Method of Pasteur . . 202
TABLE OF CONTENTS.
PAGE
Method of Toussaint 204
Method of Chauveau 205
Method by Intravenous Injection 206
Attenuation of Virus by Chemical Reagents . . 206
PART FOURTH.
GERMICIDES AND ANTISEPTICS.
Acetic Acid 215
Alcohol 215
Aluminium Acetate 216
Aluminium Chloride 216
Ammonia 216
Aromatic Products of Decomposition 216
Arsenious Acid 216
Benzoic Acid 217
Boric Acid 217
Bromine 218
Camphor 218
Carbonic Acid 218
Carbonic Oxide 219
Carbolic Acid 219
Chloral Hydrate 220
Chloroform 220
Chlorine 220
Chromic Acid 221
Citric Acid 221
Creosote 222
Cupric Sulphate 222
Ether 222
Eucalyptol 222
Ferric Sulphate 222
Ferri Chloridi Tinct 223
Glycerine 223
Heat 223
Hydrochloric Acid 'JiM
Hydrogen 225
Iodine 225
Mercuric Bichloride 225
TABLE OF CONTENTS. xiii
PAGE
Nitric Acid 226
Nitrous Acid 226
Oil of Mustard . . 226
Oil of Turpentine 226
Osmic Acid 226
Oxalic Acid 226
Ozone 227
Oxygen 227
Picric Acid 227
Potash 227
Potassium Arsenite 228
Potassium Chlorate 228
Potassium Iodide 228
Potassium Nitrate 228
Potassium Permanganate 228
Pyrogallic Acid 229
Pyroligneous Acid 229
Quinine 229
Salicylic Acid 229
Soda 230
Sodium Biborate 231
Sodium Chloride 231
Sodium Hyposulphite 232
Sodium Sulphite 232
Sodium Salicylute 232
Sulphuric Acid 233
Sulphurous Acid 233
Sulphuretted Hydrogen 234
Tannic Acid 234
Thymol 234
Zinc Chloride 234
Zinc Sulphate 235
PART FIFTH.
BACTERIA IN INFECTIOUS DISEASES.
Anthrax 265
Symptomatic Anthrax 280
Cerebro- Spinal Meningitis 284
XIV TABLE OF CONTENTS.
PAGE
Cholera 285
Erysipelas 286
Cholera of Fowls 288
Diphtheria 291
Disease produced by Bacilli 297
Fatal Epidemic among Fish caused by Bacteria 299
Glanders 299
Gonorrhoea 301
Hydrophobia 314
Intermittent Fever 317
Leprosy 331
Malignant (Edema 336
Milk Sickness 339
Measles 340
Pleuro-Pneumonia 341
Infectious Pneumonia 342
Pyaemia in Rabbits 343
Relapsing Fever 346
Scarlet Fever 349
Septicaemia in Mice 351
Septicaemia in Rabbits 355
Spreading Abscess in Rabbits . 376
Swine Plague 378
Syphilis 380
Tuberculosis 384
Typhoid Fever 400
Ulcerative Endocarditis 411
Variola 411
Variola of Pigeons 413
Whooping Cough 415
Yellow Fever , 417
PART SIXTH.
BACTERIA IN SURGICAL LESIONS , 442
BIBLIOGRAPHY 457
INDEX 489
PEEFACE BY TRANSLATOR
HAVING found the admirable resumS of our knowl-
edge of the bacteria, by Dr. Magnin, of great assistance
to me, in pursuing the investigations in which I have
been engaged during the past year under the auspices
of the National Board of Health, it has seemed to me
that a translation of the work into English and its publi-
cation in this country would be productive of good in
more ways than one, and of the advancement of science.
To the naturalist, it cannot fail to be of value, as the
most approved classification, that of Cohn, is given,
with a full description of species. To give additional
value to this portion of the work, figures of many of the
best-known forms, drawn from various foreign sources,
and reproductions of some of my own photo-micro-
graphs (by permission of the National Board of Health),
have been introduced.
If we are to judge from the scanty literature of the
subject in this country, the amount of interest which
has been aroused by the revelation of a new world of
micro-organisms, and by the momentous questions which
have been raised in connection with them, is far below
that awakened in Germany, France, and England. This
is not, however, really the case ; for, while we have but
few active workers in the difficult fields of inquiry
XVI PREFACE BY TRANSLATOR.
which have proved so attractive, especially for the Ger-
man and the French savants, there is nevertheless a
wide-spread interest in these investigations, and a desire
to know their results. But, just here, we are met with
a difficulty which has no doubt discouraged many, and
perhaps caused some to drop the whole subject in dis-
gust. The results have been so contradictory, and so
many would-be savants have uttered opinions entirely
opposed the one to the other, that we find it impossible
to arrive at any definite opinion, not knowing whom to
believe. This being the condition of affairs, it seems to
me that it is necessary for us to commence investigating
for ourselves, — first making ourselves familiar with what
has been done abroad, and then avoiding, if possible, the
quicksands into which unfortunate science has too often
been dragged by her votaries. One great trouble
which we have experienced in this country is in judg-
ing of the comparative value of the observations of dif-
ferent men who are equally unknown to us. A very
plausible article may be written by a very careless
observer ; or a very cautious observer may fail to give
confidence in his results, because of a certain degree of
confusion in his language. When experiments are well
devised, carefully executed, and described with preci-
sion, as is done by such men as Pasteur and Tyndall, we
cannot fail to attach great weight to the conclusions
reached. And when so accomplished a microscopist as
Cohn or Koch asserts that he has seen such and such a
thing, or has made such and such measurements, we
cannot doubt the reliability of the observation. But
sometimes we are deceived by giving credence to a man
who has achieved reputation in one line of study, but of
PREFACE BY TRANSLATOR. XV11
whose skill and training in the use of the microscope we
have no means of judging. Such a man may be a great
surgeon, or a great clinician, or a great chemist, and yet
be a mere tyro with the microscope. When, then, we
see it announced that Dr. So-and-so failed to discover
any micrococci in pus, in blood, or what -not, taken from
a certain source, we are justified in asking, — first, what
power did the learned doctor use ? second, is he capa-
ble of distinguishing micrococci in fluids which contain
them beyond question? Or, if he does discover them,
we may ask if he is accustomed to making a differential
diagnosis between micrococci and inorganic granular
material, or unorganized granules of organic origin.
This is a decision which the most accomplished micro-
scopist is sometimes unable to make, except by the aid
of chemical tests and culture experiments.
To avoid this want of confidence in results, which has
naturally grown out of carelessly made observations and
contradictory statements, it is desirable that full and
minute details should be given of all observations and
experiments made, and, whenever possible, that photo-
micrographs should be made of all micro-organisms
described, or of a thin stratum of a liquid asserted not
to contain any ; as, when a sufficiently high power is
used, this settles the question of their presence or
absence, beyond dispute, and enables other students to
make comparisons and measurements which cannot fail
to promote the interests of true science.
The National Board of Health of the United States
has the credit of first adopting this method of recording
the results of scientific investigation, in this direction,
as a constant and unimpeachable record of what has
XV111 PREFACE BY TRANSLATOR.
r
been seen by the investigator. The commission sent to
Havana last summer for the investigation of j^ellow
fever, was instructed to pursue this method, and was
accompanied by a photographer and supplied with all
the necessary appliances for carrying these instructions
into effect.
The superficial reader may find much to criticise in
the work of Dr. Magnin, but I am convinced that
those who read it carefully cannot fail to be pleased
with the truly scientific spirit in which it is written ;
the fairness with which conflicting opinions are stated ;
the caution manifested as to the drawing of definite
conclusions where questions are still under discussion ;
and, above all, the extent of his literary researches and
the systematic way in which he has arranged the re-
sults.
For the naturalist, for the physician, or for the non-
professional man of general culture, who desires to have
accessible in a condensed form the most important re-
sults achieved in this line of inquiry up to the present
day, this volume cannot fail to be of value ; while for
the student and the investigator in search of fuller
information, the summary given of the labors of nu-
merous individuals, together with the copious bibliog-
raphy, which I have brought up to date, will doubtless
be of service. Believing this to be true, it has been a
pleasure for me to devote a portion of my summer vaca-
tion to the translation of this little volume.
G. M. S.
SALEM, MASS., August 1, 1880.
LIST OF PLATES.
PLATE PAGE
I. The Cilia of B. termo and S. voluntans. (Drysdale
and Dallinger) 40
II. Different Modes of Grouping of the Bacteria. (Photo-
micrographs by Dr. Stern berg) 17
III. Bacilli and Spores. (Photo-micrographs by Dr. Stern-
berg) 58
IV. Disease-Ferments of Wort and Beer. (Pasteur) . . 84
V. Different Forms of Bacteria. (Cohn) 95
VI. Micrococci. (Photo-micrographs by Dr. Sternberg) 127
VII. Pathogenic Bacilli 264
VIII. Bacillus anthracis. (Photo-micrographs by Dr. Stern-
berg) 272
IX. Bacillus tuberculosis. (Chromo-lithograph) .... 396
X. • Blood of Yellow Fever Patients. (Photo- micrographs
by Dr. Sternberg) 421
INTRODUCTION.
PART FIRST.
MOEPHOLOGY OF THE BACTERIA.
PART SECOND.
PHYSIOLOGY OF THE BACTERIA.
BY
DR. ANTOINE MAGNIN,
LICENTIATE OF NATURAL SCIENCES; CHIEF OF THE PRACTICAL LABORS IK NATURAL
HISTORY TO THE FACULTY OF MEDICINE OF LYONS; LAUREATE OF THE FACULTY
OP MEDICINE OF PARIS (SILVER MEDAL, 1876); GENERAL SECRETARY
OF THE BOTANICAL SOCIETY OF LYONS; MEMBER OF THE
BOTANICAL SOCIETY OF FRANCE; ETC.
TRANSLATED FROM THE FRENCH
BY DR. GEORGE M. STERNBERG.
THE BACTERIA.
INTRODUCTION.
" Corruptio unius est generatio al terms."
LUCRETIUS, De Rerun, Natura.
OF all the studies which have for their object
the inferior organisms, those which relate to the
bacteria offer, without contradiction, the greatest
interest, as they touch the most diverse problems,
which, it is true, are the most difficult and the
least known in biology. The history of these mi-
nute organisms is, in truth, related to that of
spontaneous generation, to that of the fermenta-
tions, to the pathogeny and therapeutics of a great
number of virulent and contagious affections, and,
in a more general manner, to all the unknown
which, notwithstanding the efforts of modern sci-
ence, still surrounds the origin of life and its pres-
ervation.
If the relation of these inferior organisms to
the origin of living beings is yet obscure, their
role in the preservation of life is better known.
It is known that organic matter, once produced
and become solid, so to speak, cannot again enter
into the general current until it has undergone
12 THE BACTERIA.
new transformations, metamorphoses produced, ac-
cording to some savants, favored, according to
others, but, without contradiction, accompanied
by the development of bacteria;1 and, without
wishing to attribute to these organisms a finality
which is repugnant to our monistic conception of
the universe, it may be said that it is thanks to
them that the continuation of life is possible on
the surface of the globe.
But, if these studies are full of interest, their
field is so vast that we cannot flatter ourselves
that we have passed over the whole of it with
equal care. The little time that has been ac-
corded us for the composition of this thesis will
be our excuse for the inevitable imperfections
which will doubtless be found in our work.
1 The bacteria : such is the subject which has been imposed upon us ;
but it is certainly useless to give the reasons which have caused us to
study not only the bacteria properly so called, taking the word in its
most restricted sense, but all the organisms which are comprised under
the names of bacteria, vibrios, schizomyce'tes, schizophytes, etc.
HISTOKICAL.
THE bacteria are the lowest organisms, situated
upon the limit of the two kingdoms, animal and
vegetable, and are thus defined by the botanists
who have most recently occupied themselves with
them : —
" Cells deprived of chlorophyll, of globular, ob-
long, or cylindrical form, sometimes sinuous and
twisted, reproducing themselves exclusively by
transverse division,1 living isolated or in cellular
families, and having affinities which approach them
to the algae and especially to the oscillatoriae."
But, before arriving at this degree of relative
precision, the history of the bacteria has passed
through the most diverse vicissitudes. At one
time considered as animals, at another taken for
vegetables, transported from the algae to the fungi,
one author has even gone so far as to refuse to
them the nature of living beings.2 This diversity
of opinions is due to the minuteness of their di-
mensions and the difficulties with which their ob-
servation is surrounded.
1 Reproduction by the formation of endogenous spores also occurs
among the bacilli. (See plate III.) — G. M. S.
2 Polotebnow.
14 THE BACTERIA.
Although an historical statement of the progress
of our knowledge of these minute organisms has
been given in several publications, we think it best
to make here a new historical summary, which will
be completed by an indication of the principal pa-
pers relating to them which have been published
recently.
The first observer who perceived bacteria was
Leeuwenhoeck. As early as 1675, while examin-
ing by chance with his magnifying glasses a drop
of putrid water, the father of microscopy re-
marked with profound astonishment that it con-
tained a multitude of little globules, which moved
with agility. The following year he recognized
the presence of bacteria in faeces and in tartar
from the teeth ; and, if he has not named them,
it is easy to assure one's self by the description
which he has given of their form and of their
movements, and by the figures which accompany
these descriptions,1 that the organisms observed
by him are truly Bacteria, Vibrios, and perhaps
even Leptothrix.
In 1773 0. F. Muller endeavored to classify
these organisms. He made of them a group of
infusoria, under the name of Infusoria crassius-
cula, and established two genera, — the g. Monas
and Vibrio ; the first characterized as follows :
" vermis inconspicuus, simplicissimus, pellucidus,
punctiformis," comprising the following species:
Monas termo, atomus, punctum, ocellus, lens, mica,
1 Leeuwenhoeck. Opera omnia, Lugd. Batar., 1722, 11, p. 40, fig. A to G.
HISTORICAL. 15
trnnquiUa, lamellula, pulviscidus, uva, which it
is impossible to identify with the species at pres-
ent recognized. The genus Vibrio " vermis incon-
spicuus, simplicissimus, teres, elongatus" enclosing
under thirty-five specific names, with the true
bacteria, some organisms belonging to other
classes of the animal and vegetable kingdoms.
In the classification of the infusoria given by
Bory de Saint-Vincent in the " Encyclopedic
Methodique" (1824) and afterwards in the " Dic-
tionaire Classique d'Histoire Naturelle" (1830) the
bacteria are distributed in two different families
of the microscopic gymnodae, the monadaires and
the vibrionides. Besides the monads, properly so
called, of which the Monas termo has been pre-
served by the greater part of the bacterologists,
the monadaires include some veritable infusoria,
which have no relation with the monads. It was
the same with the vibrionides, of which the genera
Vibrio and Mellanella included some beings very
different in their organization. Indeed, beside
some veritable vibrios, bacteria, and spirilla,
constituting the genus Mellanella, Bory placed
some nematoid worms, such as the Anguillula
of vinegar.
With Ehrenberg (1838) and Dujardin (1841)
the family of the vibrioniens was established upon
characters more homogeneous, and their species
upon distinctions truly scientific. But these two
observers, followed in this by M. Davaine, deny
completely the affinities of the elongated bacteria
16 .THE BACTERIA.
(Bacterium, Vibrio^ etc.) with the punctiform
bacteria ( Monas] ; and it is necessary to come
to the time of MM. Hallier, Hoffmann, Cohn, and
the greater number of recent botanists, in order
to see these two forms brought together anew.
In fact, Ehrenberg defines his vibrioniens, which
he arranges between the volvocinece and the
closteria " animals, filiform, distinctly or appar-
ently polygastric, no mucous membrane, naked,
without external organs, with the body (like mon-
ads) uniform and united in chains or filiform se-
ries, as a result of incomplete division." He
included in this class all filiform bodies gifted
with proper movement and formed of articles,
dividing them into four genera : —
1. Bacterium: filaments linear and inflexible; three
species.
2. Vibrio : filaments linear, snakelike, flexible ; nine
species.
3. Spirillum : filaments spiral, inflexible ; three spe-
cies.
4. SpirocTicete : filaments spiral, flexible; one species.
A fifth genus, including but one species, the
Spirodiscus fulvus, with filaments in a helix, in-
flexible, disposed in contiguous layers, has not
been seen since Ehrenberg. Let us add that
Ehrenberg often attributed to them a complex
structure, stomachs more or less numerous, a pro-
boscis, cilia serving as organs of locomotion, —
all characters that more recent observers have
failed to find. Nevertheless, we must make an
HISTORICAL. 17
exception in favor of the cilia, of which the ex-
istence has been recently verified in the case of
several of the bacteria by divers botanists, among
others by MM. Cohn and Eug. Warming.
Dujardin (1841), in his " Histoire Naturelle des
Zoophytes/' preserved the family of the vibrioni-
ens of Ehrenberg among the infusoria, characteriz-
ing them as follows : " filiform animals, extremely
slender, without appreciable organization, without
visible locomotive organs." He made but few
modifications, of which the principal consisted in
uniting Spirochceta with Spirillum, Dujardin. Re-
jecting the character that Ehrenberg drew from
the rigidity of the spirilla, the Spirochceta pllca-
t'dis, Ehrb. became the Spirillum plicatile, Duj. ;
but, as will be seen later, this change has not
been maintained. Dujardin, then, classed the bac-
teria in :
1. Bacterium : filaments rigid, with a vacillating
movement.
2. Vibrio: filaments flexible, with an undulatory
movement.
3. Spirillum : filaments spiral, movement rotatory.
Until this time the bacteria had been considered
as animals placed at the foot of the series. Sub-
sequently the tendency to place them in the
vegetable kingdom became more and more pro-
nounced.
Already, since 1853, M. Ch. Robin had pointed
out the relationship of the bacteria and of the
2
18 THE BACTERIA.
vibrios with Leptothrix. This opinion, which
was not favorably received by the authors who
adopted nearly all of the generic groups of Ehren-
berg and Dujardin, is to-day accepted by many
botanists, above all since the labors of Cohn. (See
below: classification.) At all events, it is to M.
Davaine (1859) that we are indebted for clearly
pointing out that the vibrioniens are vegetables,
nearly allied to the algae, and especially to the
confervas.
This same author, having observed some mo-
tionless bacteria, thought it necessary to give
this character great consideration, and to estab-
lish a fourth group, the genus Baeteridium, which
he added to the three others admitted by Dujar-
din ; but in this creation he was less happy than
in his placing the vibrioniens among the vege-
tables ; for we shall see further on that this char-
acter of mobility or of immobility is not absolute,
and that it depends upon the age of the bacterium
or upon certain conditions relating to the medium
in which it is placed.
The most recent complete exposition of the
classification and of the ideas of M. Davaine is
found in the " Dictionnaire Encyclop. des Sci-
ences M£dicales," art. Bacteries (1868). It may
be summed up as follows : —
Filaments straight
or bent, but not
in a spiral .
Moving sponta-) Rigid. . BACTERIUM.
neously . . j Flexible . VIBRIO.
Motionless .... BACTKKIDIUM.
Filaments spiral SPIRILLUM.
HISTORICAL. 19
The genus Bacterium comprises six species, —
S. termo, catenula, punctum, triloculare, or articula-
tum, already described by Ehrenberg and Dujar-
din, and B. putredinis and capitatum, new species
of M. Davaine, established, the first for a bacte-
rium producing rot in plants, the second for a spe-
cies, swollen at the extremity, observed in some
macerations.
The genus Vibrio includes twelve species, —
V. lineola, tremulans, rugula, prolifer, serpens,
bacillus, synxanthus, and syncyanus of previous
authors and the V. lactic, butyric, and tartaric
right, discovered by M. Pasteur in these different
fermentations.
In the genus Bacteridium, M. Davaine places
five new species, — the " Bacteridies charbonneuse,
intestinale, du levain, glair euse, et des infusions."
He includes also the ferment which, according to
M. Pasteur, occasions the " sickness of turned
wine."
Finally, the genus Spirillum includes the spe-
cies S. undula, tenue, volutans of Ehrenberg, S.
rufum and leucomcenum of Perty, and S. plicatile,
Duj.
From this moment the history of the bacteria
enters upon a new phase. The labors of M. Pas-
teur upon the inferior organisms and their role in
fermentation, the researches of MM. Davaine and
Hallier upon the bacterium of charbon, and the
micrococci of contagious maladies, call the atten-
tion of chemists and of pathologists to these or-
20 THE BACTERIA.
ganisms and especially to the bacteria. Their
origin, their evolution, the physiological peculi-
arities of their nutrition and reproduction, are
the object of numerous labors, and give rise to
passionate discussions relating to the subject of
spontaneous generation, polymorphism of fungi,
theories of fermentation, and the pathology of
virulent and infectious maladies. For this reason
an exposition of these researches, often contradic-
tory, is extremely difficult. We will make it suc-
cinctly, insisting especially upon the labors relating
to the classification of the bacteria, and reserving
to ourselves the privilege of returning to the his-
tory of several points, when we approach their
study in the special chapters of this thesis.
The first important memoir published after
that of M. Davaine upon the bacteria is that of
M. Hoffmann, in 1869. He demonstrates : First,
that the bacteria are plants, having a very distinct
cellular organization ; second, that they can only
be classified in accordance with their form and
size, at first into monads and linear bacteria, and
the latter into microbacteria, mesobacteria, and
megabacteria ; (M. Hoffmann includes with the
linear bacteria, Vibrio, Bacterium, and Leptotlirix,
which are bacteria united in a chaplet ;) third,
that mobility or immobility is not a specific char-
acter, but may present itself in the same species
under the influence of changes of temperature, of
density of medium, etc. M. Hoffmann studied
also the origin of the bacteria, and rejects the
hypothesis of a spontaneous generation. As to
HISTORICAL. 21
their role in the phenomena of the decomposition
of organic bodies and in fermentations, M. Hoff-
mann confesses " that, with the exception of yeast
and of the acetic and butyric ferments, all the rest
is still enveloped in obscurity."
M. Cohn is the naturalist who, in our days, has
occupied himself the most with the bacteria. In
1853, he published his first researches upon this
subject. The genera Zoogloea, which he estab-
lished at this time for the bacteria arranged in ge-
latinous masses, diffused or more or less crowded
together, was not a happy creation. It was adopt-
ed at first by M. Rabenhorst who, in his work on
the fresh-water algae of Europe, places them after
the palmellaceae, while he classes the other bac-
teria, Vibrio and Spirillum, in the family of the
oscillatoriae. The Zooglcea were later abandoned by
their author as a generic group, and are preserved
only as the name of one of the diverse transitory
stages through which the bacteria pass in .the
course of their evolution (Zooglcea, Leptothrix,
Toruld).
Twenty years later the same savant commenced
the publication of a series of " Memoirs " upon
these organisms (in his " Beitrage zur Biologie der
Pflanzen"). In the first paper the author gives an
exposition of his researches upon the organization,
development, and classification of the bacteria, and
upon their action as ferments.
M. Cohn considers them as a well-defined group,
— the schizospores, belonging to the algae, at the
commencement of the series of the phycochroma-
22 THE BACTERIA.
cese, with several families with which the different
genera of bacteria have many affinities. He rec-
ognized, however, that the absence of chlorophyll
approaches them, at least from a functional point
of view, to the fungi. Upon this point we may
say that for other botanists this character is de-
cisive, and the bacteria are classed as fungi.
M. N'ageli, who takes this view, describes them
under the name of Schizomycetes. Cohn divides
the bacteria into four tribes, comprising six
genera : —
1. The Sphcerobacteria or globular B.
2. The Microbacteria or rod B.
3. The Desmobacteria or filamentous B.
4. The Spirobacteria or Spiral B.
We will return to this classification.
In 1874, M. Th. Billroth, in his researches upon
the Coccobacteria septica, expressed opinions en-
tirely different from those of Cohn. According
to Billroth, the bacteria differ considerably in
form according to the medium in which they are
placed and divers circumstances. He claims that
they constitute but a single species, the C'occobac-
teria septica. This vegetable organism can pre-
sent itself under the form of globular articles
(coccos) or under that of rods (bacterie). These
two forms may reproduce themselves by becoming
elongated and dividing transversely, or may pass
the one into the other. Billroth claims to have
found both forms united in a single filament, a
HISTORICAL. . 23
fact which in his opinion demonstrates conclu-
sively their relationship. Each of these two
forms can also present variations of size, in ac-
cordance with which he establishes the following
divisions : —
Micrococcos Microbacteria.
Mesococcos Mesobacteria.
Megacoccos Megabacteria.
And varieties of association which give rise to the
following names : —
Monococcos Monobacteria.
Diplococcos Diplobacteria.
Streptococcos Strep tobacteria.
Gliacoccos Gliabacteria.
Petalococcos Petalobacteria.
Ascoccos.
The following year (1875), Cohn, in the second
part of his " Researches " upon the bacteria, criti-
cised the opinions expressed by Billroth in the pre-
ceding memoir. Cohn believes that we should
regard as distinct genera and species all the bac-
teria having a particular form and acting differ-
ently as ferments, so long as the proof of their
identity has not been demonstrated in an evident
manner. Coming back also to the affinities and
classification of these organisms, he insists anew
upon their near relationship to the Phycochro-
macese; and, no longer distinguishing the bac-
teria as a special family, he distributes his
different genera in a group, which he calls Schi-
zopkytes, which includes the greater part of the
24 THE BACTERIA.
r
Chrococcece and of the Oscillarice. We will re-
turn to this subject when we speak of the clas-
sification of the bacteria.
In 1876, appeared in the same number of
Cohn's " Beitrage " two important papers. The
first, by Cohn, treats of the influence of tempera-
ture upon the bacteria, of • their origin, of the
formation of spores ;n the Bacillus of. hay infu-
sion, and of charbon. The second, by Koch,
gives the result of his researches upon the bac-
teria of charbon, the Bacillus anthracis.
Koch has been able by skilful cultivation to
follow the complete development of this Bacillus,
and to witness the formation of spores, of which
the vitality is very great, and which are the prin-
cipal agents of the transmission of this terrible
malady.
I must still indicate, in addition to these special
works, a quantity of notes and of memoirs scat-
tered through the reviews and periodical publica-
tions.
The list will be found in the bibliography ap-
pended to this work. I must also cite the recent
work of M. Nageli upon " The Inferior Fungi
and their Role in Infectious Maladies." The
learned professor of Munich has studied the di-
verse fungi which produce decompositions. He
divides them into three groups, — the Mucorini,
the Saccharomycetes, and the 8M0ompcetes, which
correspond to the bacteria. According to Niigeli,
HISTORICAL. 25
the bacteria are fungi which produce putrefac-
tion.
In presence of these opinions, so diverse, as to
the nature of the bacteria and their classification,
we will finish by saying with Cohn : —
" So long as the makers of microscopes do not
place at our disposal much higher powers, and, as
far as possible, without immersion, we will find
ourselves, in the domain of the bacteria, in the
situation of a traveller who wanders in an un-
known country at the hour of twilight, at the
moment when the tight of day no longer suffices
to enable him clearly to distinguish objects, and
when he is conscious that, notwithstanding all his
precautions, he is liable to lose his way."
PART FIRST.
MORPHOLOGY OF THE BACTERIA,
CHAPTER I.
ORGANIZATION OF THE BACTERIA.
WHEN bacteria develop in a liquid in a suffi-
cient quantity, they become visible to the naked
eye. They appear either as a slight cloud, or
gathered in little masses in the liquid, or forming
a pellicle upon its surface, or as a deposit upon the
walls of the vessel and upon the objects contained
in the liquid. However, we must hasten to say
with M. Cohn, that the fact of the absence of all
turbidity in a liquid does not exclude the possi-
bility of the presence of bacteria. In liquids more
dense than water (serum, lymph, etc.), when the
refractive power of these corpuscles is the same as
that of the liquid, their presence may not be
revealed to the naked eye. We will add that
sometimes their color serves to indicate their
presence in a liquid, although this color is often
very feeble, and can only be perceived when a
considerable thickness of the liquid is examined.
If we examine these clouds, these accumulations,
these deposits, with the microscope, we see that
28 MORPHOLOGY OF THE BACTERIA.
they are formed of a myriad of little bodies 'iso-
lated or grouped, globular or linear, gifted or not
with motion, sometimes colored. These variations
constitute so many characters which require to be
studied with some detail.
§ 1. BACTERIA IN GENERAL.
Form. — The bacteria, as understood to-day by
most botanists, when considered in their separate
state, are of two principal forms, — globular bod-
ies, or monads, and bodies more or less filiform, or
bacteria properly so called.
The globular bacteria comprise organisms round-
ed, ovoid, sometimes elongating themselves into a
tube (Warming). The Monas crepusculum of
Ehrenberg may be taken as a type. This form
includes also the Micrococcus of Hallier, the Mi-
crosporon of Klebs, the round forms of the Amy-
lobacter of M. Trecul, and perhaps the Microzyma
of M. Bechamp. We will see farther on that
these are very probably phases of development of
the spores of bacteria, properly so called.
The bacteria, not globular, present a greater
diversity of form ; they may be straight, undu-
lating, or twisted in a spiral.
The rectilinear bacteria are usually exactly
cylindrical throughout their whole extent ; and in
this case they form very short cylinders, as in the
Bacterium,Cohn, or cylinders of which the length
is several times as great as the thickness, as in
the Bacteridies (Bacillus ulna Cohn) ; others are
ORGANIZATION OF THE BACTERIA. 29
swollen in the middle, with their extremities
rounded, such as certain forms of Vibrio serpens
(Warming) ; others again are fusiform, swollen in
the middle and attenuated at the extremities, —
Bacterium fusiforme (Warming) ; rectilinear bac-
teria swollen at the two extremities are met
during the life of certain species, B. lineola and
B. termo, for example, above all when they are
transported to a more favorable medium : this
modification usually precedes segmentation ; final-
ly, one meets sometimes bacteria swollen at one
extremity only; the swollen part presents often
a clear point and sometimes an evident spore : we
shall see later the signification of this peculiarity.
With these claviform bacteria we may include the
Bacterium capitalum Dav., the Helobacteria of
Billroth, and certain Amylobacter, with heads of
the Ficus carica, etc. (Ch. Robin).
The undulating bacteria constitute the Vibrios
properly so called (V. rugula, serpens, etc.).
The spiral bacteria of which the turns are more
or less elongated are named Spirillum, Spiro-
chceta, etc.
Dimensions. — The dimensions of the bacteria
oscillate between the most variable limits, but in
a general way it may be said that they are the
smallest of all microscopic beings. Some of them
are situated at the extreme limit of our highest
magnifying powers; and their proportions, as to
30 MORPHOLOGY OF THE BACTERIA.
length and thickness, are comprised within the
limits of errors of observation.
The globular bacteria are the smallest, and the
dimensions of some species are so minute that
they cannot be measured directly.
The largest are the Spirillum, which attain a
length of y2^- of a millimetre. Between these two
extremes, there are all intermediary sizes possible.
The dimensions of some of the bacteria are given
below: —
Monas vinosa, 0.5 to 1 /-t, in diameter; length 3
to4|k
Bacterium termo, breadth 0.6 to 0.8 ^; length 2
to 3/4.
Vibrio lineola, breadth 0.5 to 1 p ; length 3 to 8 //,.
Bacillus ulna, „ 0.7 to 1 /z ; „ 5 to 8 /it.
B. anthracis, „ 1 to 2 //, ; ,,10 to 50 p.
Spirillumvolutans, „ 7 /z ; ,,10 to 40 JJL.
Several authors, considering exclusively this
character of dimensions, have divided the monera
and the bacteria according to their size. Thus
Hoffmann recognizes in addition to the monera,
only the microbacteria, the mesobacteria, and the
macrobacteria. In the same way Billroth classi-
fies the monads according to their dimensions into
micro, meso, mega coccos, and the bacteria into
micro, meso, mega bacteria. Finally, Klebs sep-
arates the Micrococcos from the Microsporines,
which do not differ from them except by their
smaller dimensions, both forms being able to pass
to the state of bacteria (rods).
ORGANIZATION OF THE BACTERIA. 31
Color. — The phenomena relating to the color
of bacteria have only recently been pointed out.
" But little attention has been given to the color
of the bacteria, regarded generally as colorless,"
said M. de Seynes in 1874 ; and recently M. de
Lanessan, " The bacteria are ordinarily quite color-
less." However, M. Cohn had already insisted
upon the globular bacteria chromogenes, or of pig-
mentary fermentation, and upon the colors pro-
duced by different monads, which have long since
been studied by microscopists.
Upon this subject, let us observe that the bac-
teria which are colored belong to two very dif-
ferent groups. First, colored organisms always
known as such, but which were not formerly in-
cluded with the bacteria, as the different monads,
which have become the Micrococcus prodigiosus,
cyaneus, aurantiacus,Cohn, etc. ; the second group
includes the bacteria properly so called, which
absorb the coloring matter of vegetables upon
which they are fixed as parasites, or of the media
in which they live. This is the case with the bac-
teria observed by M. de Seynes upon the Penicil-
lium glaucum, and perhaps with the Vibrio syn-
xanthus and sy?icyam^s,Ehrenb., which give to milk
a yellow or blue color according to the species.
We will return to this subject when we speak of
the nutrition of the bacteria.
As to the purple-colored monads, they have
been especially studied as early as 1838 by Dunal,
then by Morren and Ehrenberg, and in our own
day by Kay-Lankester, Cohn, Klein, and finally
32 MORPHOLOGY OF THE BACTERIA.
by Warming and Giard. They are found in va-
rious media — in sea- water, in hot sulphur springs,
in fresh water containing animal or vegetable mat-
ter in a state of putrefaction. They appear some-
times upon bread, meats, and in general upon
cooked food placed in a humid atmosphere. The
different colors which they present are red, yel-
low, orange, and blue. It is probably to anal-
ogous organisms that we must attribute the blue
color presented by pus under certain circum-
stances, the green and blue color studied by
M. Chalvet, and the orange-yellow, bright red,
and blue colors observed by C. Eberth in perspi-
ration.
In Norway, red bacteria appear in summer in
such masses that the borders of the sea are some-
times colored of an intense red (Warming).
Movement. — The bacteria are met in two dif-
ferent states. They are active or motionless ; but
it is now well settled for the greater number that
the same species may present itself sometimes in
a state of repose, sometimes in a state of move-
ment.
The movements of the bacteria are of two kinds,
— a movement of the corpuscle upon itself and a
movement of translation. The first is sometimes
nothing more than a molecular or brownien move-
ment, which occurs in the smallest forms. But at
other times it is more extended, and consists in a
movement of rotation round the axis, or a bend-
ing of the body. This flexibility is, above all,
ORGANIZATION OF THE BACTERIA. 33
observed in the long forms, the Bacillus, the V'ib-
rions, etc. As to the movement of translation,
it is very variable ; at one time slow, at another
rapid, it is in relation with the length and form
of the bacterium. M. Cohn has well described all
the modifications of movement in the following
lines : —
" Almost all the bacteria possess two different
modes of life, characterized by repose and by
movement.
" In certain conditions, they are excessively
mobile ; and when they swarm in a drop of
water, they present an attractive spectacle, sim-
ilar to that of a swarm of gnats, or an ant-hill.
The bacteria advance, swimming, then retreat
without turning about, or even describe circular
lines. At one time they advance with the ra-
pidity of an arrow, at another, they turn upon
themselves like a top ; sometimes they remain
motionless for a long time, and then dart off
like a flash. The long rod-bacteria twist their
bodies in swimming, sometimes slowly, sometimes
with address and agility, as if they tried to force
for themselves a passage through obstacles. It
is thus that the fish seeks its way through aquatic
plants. They remain sometimes quiet, as if to re-
pose an instant: suddenly the little rod commences
to oscillate, and then to swim briskly backwards,
to again throw itself forward some instants after.
All of these movements are accompanied by a
second movement analogous to that of a screw
which moves in a nut. When the vibrios" in the
3
34 MORPHOLOGY OF THE BACTERIA.
shape of a gimlet turn rapidly round their axis,
they produce a singular illusion : one would be-
lieve that they twisted like an eel, although they
are extremely rigid."
The causes of these movements have been sought,
at first, in the supposed animal nature of the bac-
teria, and the movements assimilated, consequently,
to voluntary movements ; but this opinion can no
longer be sustained, as similar movements are to
be seen in a great number of vegetable organisms,
such as the diatoms, the oscillatorise, the spores of
algae and some fungi, etc. They have also been
attributed to the existence of locomotor appen-
dices (Ehrenberg) ; but, although the cilia, denied
at first by most microscopists, have been seen since
in nearly all the bacteria, the botanists who have
best studied them, M. Warming, for example, rec-
ognize that it is scarcely probable that these or-
gans are the cause of their movements, for " one
meets some examples in which the body remains
motionless while the cilia are in violent agitation,
and others in which the body moves while the cilia
remain inert, or dragging behind."
The movements appear to depend rather upon
the nutrition, or respiration, and especially upon
the presence of oxygen (Cohn); indeed when this
gas is wanting the bacteria become motionless.
Immobility may also be produced by want of
nutriment, poisoning by different toxic substances,
(chloroform, iodine, etc.), dessication, etc.
The attempt has been made to use the charac-
ters derived from the existence or absence of
ORGANIZATION OF THE BACTERIA. 35
motion, and the form of the bacteria, in order to
classify them ; but what has just been said shows
clearly that these transitory phenomena cannot be
taken for generic or specific characters.
Structure. — It was for a long time believed that
the bacteria were constituted of amorphous masses
of protoplasm, or of solid rods. The researches of
Hoffmann have shown that they have a true cellu-
lar structure. We shall describe, then, succes-
sively, their membrane, the contents, and the cilia,
which may be considered as belonging to the pro-
toplasm.
Cell-membrane. — The extreme minuteness of
the bacteria usually prevents a direct demonstra-
tion of the cell-membrane, and the existence of
this envelope has not, heretofore, been clearly
demonstrated except by indirect proofs ; chemical
reactions, for example.
Thus Hoffmann verifies the existence of a cellu-
lar envelope when " the contents, which is a trans-
parent plasma, are partly coagulated, as sometimes
happens, or disappear, and are then replaced by
air which shows precisely the form of the normal
bacterian cell." Warming, also, has not been able
to see the membrane, " which only appears dis-
tinctly when a vacuole has formed just against the
periphery."
On the other hand, the action of chemical agents
upon bacteria proves that they have an envelope
of cellulose, which is colored by tincture of iodine ;
36 MORPHOLOGY OF THE BACTERIA.
is not destroyed by caustic potash, ammonia, or
even acids; and resists putrefaction for an ex-
ceedingly long time. In this respect, it resem-
bles the membrane of cellulose of vegetable cells
(Cohn).
We should add that Cohn claims to have suc-
ceeded with high powers in seeing directly the
cell-membrane. On the other hand, ^Yarming has
never succeeded in so doing. The last observer
remarks also that the resistance of bacteria to
acids, to alkalis, etc., does not seem to prove the
existence of a membrane, " inasmuch as this may
be the result of a particular condition of the
plasma, which in all the bacteria is of a more con-
sistent nature than in other plants."
Finally, the membrane may be, in certain bac-
teria, tender, flexible and susceptible of move-
ments of torsion. In others, it is rigid and
incapable of bending. Cohn thinks also that it
may swell and dissolve into mucilage, a fact which
would explain the origin of this substance in the
Zooglcea.
Protoplasm. — The contents of the cell is a
nitrogenous substance, generally colorless, more
highly refractive than water.
In the smallest species, this protoplasm appears
homogeneous ; but in the bacteria of medium size,
and above all in the large species, the contents of
the cell encloses portions more highly refractive,
vacuoles, special granules, and sometimes diverse
coloring matters.
ORGANIZATION OF THE BACTERIA. 37
Cohn first pointed out the movements of the
protoplasm, in which currents occur, above all in
the central portion, the peripheral portion remain-
ing homogeneous and motionless. The vacuoles
are also found in the central portion ; Warming,
however, who has observed them in Monas Okenii,
Vibrio rftgula, V. serpens and Spirillum undula
var. littoreum, has sometimes seen them in the mid-
dle of the plasma, at another near the exterior wall.
The granules which are seen in the protoplasm
were considered by Ehrenberg as stomachal vesi-
cles or ovules. They are of two sorts ; the one,
highly refractive and not bordered by a dark circle,
are considered by Warming as nothing more than
mere compact masses of protoplasm ; the second,
also highly refractive, but surrounded by a dark
circle, resemble drops of oil, and have been taken
for fat granules ; but the recent researches of
Cramer, Cohn, and Warming have proved that
some of them, at least, are formed of crystalline
sulphur. They are not soluble either in hydro-
chloric acid or in water, but they are dissolved in
absolute alcohol, in hot caustic potash and sulphite
of soda, in nitric acid and chlorate of potash at
ordinary temperatures, and in bisulphide of carbon,
when the membrane, which is permeable with dif-
ficulty, has been previously destroyed by sulphuric
acid. Although their small dimensions and great
refractive power prevent them from being dis-
tinguished with certainty as crystals of sulphur, as
they are doubly refractive to polarized light their
crystalline nature cannot be doubted.
38 MORPHOLOGY OF THE BACTERIA.
These globules of sulphur have been observed
in Monas Okenii, Bacterium sulphuratum, Ophi-
domonas, and the different species of Beggiatoa,
both in fresh water, in putrid sea- water, and in
thermal sulphur waters. It will be seen when we
speak of the physiology of these organisms what
their role is in the elimination of sulphui* and the
formation of sulphuretted hydrogen.
We have said, in speaking of the colored bac-
teria, that some borrow their color from the sur-
rounding medium, and that others, on the contrary,
have a color of their own. The protoplasm of the
latter contains a granular coloring matter, which
is ordinarily yellow, blue, or red. The red color-
ing matter is most common, and this has been best
studied, and appears to be the best known.
One of these colors which gives a pink tint
(peach color) to Bacterium rubescens, Ray-Lank.
( Clathrocystis roseopersicina, Cohn); Monas tnnosa,
Ehrb., M. OJcenii, Cohn ; M. gracilis, Warming ;
Rhabdomonas rosea, Cohn; M. Warmingii, Cohn;
Ophldomonas sanguinea, Ehrb. ; Merismopedia
littoralis, Rabenh. ; etc., has been studied by Ray-
Lankaster, who has given to it the name of bac-
terio-purpurine. It is insoluble in water, soluble
in alcohol, ether, carbolic acid, glycerine, and
fatty oils, — characteristics which make it resemble
chlorophyll. It has also a characteristic spectrum.
Other red coloring matters which appear to be
different have been found in Monas prodigiosa9
Ehrb.; Bacillus ruber, Cohn; and Micrococcus ful-
vus, Cohn. These should not be confounded with
ORGANIZATION OF THE BACTERIA. 39
the purple coloring matter of other algae, as that
of the Porphyridium cruentum, which comes from
a mixture of chlorophyll and of phycoerythrine.
The bacteria never contain chlorophyll.
In this connection, it is interesting to recall the
protoplasmic constitution of the Amylobacter of
Trecul. These organisms are, according to Yan
Tieghern, bacteria, to which he has given the name
of Bacillus Amylobacter, and which does not dif-
fer from B. subtilis, except by a specific character,
extremely transitory, — the presence of amorphous
starch, formed and stored in reserve during the
period of growth, to be again used later, and con-
sumed during the process of reproduction.
Cilia. — These appendages which were described
by Ehrenberg in the Bacterium trilocular have
not been seen since. To-day, recent researches
permit us to say that cilia exist without doubt in
all the true bacteria, — Bacillus, Bacterium, Spi-
rillum. They have been perceived in a great
number of forms, — Spirillum volutans, Sp. undula,
Vibrio rugula, Spiromonas Cohnii, Vibrio ser-
pens, and several species of Bacillus. It is only
in the smallest of the bacteria that it has hitherto
been impossible to demonstrate their presence.
They have, however, been recently seen by Dai-
linger and Drysdale in Bacterium termo. Warm-
ing has perceived as many as two or three on one
extremity in Ophidomonas sanguinea Spirillum
volutans var. robuslum, arid Vibrio rugula.
PLATE I.
Taken from " Monthly Microscopical Journal," of Sept. 1st, 1875.
FIG 1. — a. B. termo magnified with the same power as b, which
is a specimen of Spirillum volutans, showing flagella at each end.
FIG. 2. — B. termo, as seen with a power of about 600 diameters.
FIG. 3. — The same as seen with -^ and second eye-piece (3,700
diameters).
FIG. 4. — B. termo, seen with flagellum at one end, the light com-
ing in the direction of the arrow.
FIG. 5. — The same object when it moved at right angles to its
former position, the light coming from the same direction, causing
the sight of the flagellum to be lost.
FIG. 6 represents one B. termo which was in a still condition,
but one flagellum moving. The light came in the direction of the
arrow. When the end marked 2 b was in focus, a flagellum was
seen, but none at the end c. When the end marked 1 a was fo-
cused carefully, the flagellum at that end was seen, and lost at the
end d.
FIG. 7. — The true form of B. termo.
FIG. 8. — The form as shown by the " supplementary stage " il-
lumination before flagella were found, showing the pointed ter-
mination of the body at a, b.
PLATE 1 .
4'2 MORPHOLOGY OF THE BACTERIA.
were resolved into beads with the third and fourth eye-pieces. In like
manner the fine striae in Surirella gemma were instantly shown to be
beaded, with perfect and brilliant definition, with the second eye-piece.
Nacicula rhomboides and an extremely delicate specimen of Pleurosigma
attenuatum which had resisted everything below a ^th immersion, showed
beaded striae perfectly. We were therefore encouraged to try again to
discover flagella in the termo. Some of our specimens, nourished in
Cohn's nutritive fluid, were placed in a drop of distilled water, and put
upon the supplementary stage on an ordinary slide covered with the
thinnest cover. The utmost delicacy and tact in manipulation of the
light is the great desideratum ; but, with this, enough may be secured to
work with the fourth eye-piece. The light may be made to enter the
objective at almost every angle, but it is always projected in a direction
at right angles to the stage ; and the first thing we observed when the
objects were sufficiently slow in their movements, and at right angles to
the light, was that the ends of the termo, which we (and all other observers,
as far as we know) had taken for round, proved themselves to be conical,
terminating in a sharp point. The usual appearance of B. termo, as seen
with a magnification of about 600 diameters, is seen in Fig. 2 ; whilst the
same seen with a magnifying power of 3,700 diameters (sVth and second
eye-piece) is seen in Fig. 3, where a globular granule is seen in the end
of each half. But with the method above referred to, the best condi-
tions being secured, the two ends of the bacterium were distinctly pointed,
as seen at a b, Fig. 8, and after nearly five hours of incessant endeavor
a flagellum was distinctly seen at one end of each of two termos which
were moving slowly across the field. The discovery was not sudden and
transient, but lasted for at least twenty minutes. The exquisitely delicate
flagellum was lashing rapidly the whole time ; and one of its frequent
conditions is shown in Fig. 4, the arrow indicating the direction of the
light : but if the termo turned round at right angles, as in Fig. 5, all trace
of the flagellum was gone, showing that its discovery depended entirely,
all things being equal, upon its position in regard to the light.
" But this observation was made only by one of us, the other not being
present ; and in pursuance of our plan we determined to see it again,
convincing ourselves separately, and then together. After many hours
of labor, this wag accomplished ; and Fig. 6 shows one of two instances
which we both saw together at the same time and in the same instru-
ment. It was lying still, obliquely across the field, the light coming in
the direction of the arrow. Both ends were not perfectly in focus at the
same time, but in focusing the end marked 2 b (Fig. 6) the flagellum
was distinctly seen, and was seen also to coil and lash ; but no flagellum
was then seen at the end c of the same object ; but by bringing it into
delicate focus it presented the aspect seen at 1 a (Fig. 0), which really
represents the same object at the same time, only with the other end in
the focus, while the end marked d corresponding to 2 b of Fig. 6 was in
its turn slightly out of focus, and the flagellum lost to view. This ob-
servation, made together, was as satisfactory as could be desired ; and it
ORGANIZATION OF THE BACTERIA. 43
was thus demonstrated that there was a flagellum at both ends of the or-
dinary B. termo.
" It will of course be understood that it is by no means an easy matter
to secure the demonstration ; and whenever we repeat it, it must always
be with nearly the same amount of trouble and patience, although we
can now with the ordinary condenser detect the vortical action, both in
front and (occasionally) behind the termo, as we never did before. But
the demonstration of the ultimate structure of a fixed object — as for
instance Amphi pleura pellucida — must be looked upon as a matter of
great ease in comparison ; and that for many reasons, the foremost
being the motion and the minuteness of the object, the swift play of the
flagella, their similarity in optical properties to the fluid in which bacte-
ria live, the difficulty of retaining them in focus, and of getting them in
such a position in relation to the light as to make demonstration possible.
Of course, all this would be removed if dead bacteria would answer, but
they very rarely (indeed only once) have done so with us. The flagel-
lum needs to be in slow motion to properly show itself ; for even with
the more delicate and minute monads it is a difficult thing to show the
flagella in dead forms, since in the majority of cases they appear to be
attracted round the body of the creature."
§ 2. — OF THE DIFFERENT MODES OF GROUPING
OF THE BACTERIA.
The bacteria are fouDd in different media in
two states, — free, isolated (unicellular bacteria),
or united several together, either in chains, in
filaments, or in masses of greater or less extent,
and sometimes by the aid of a mucous substance
in which they are imbedded.
The free unicellular bacteria are found in the
Spirillum, Bacillus, Monas, etc. When they are
united, they are grouped in the following
modes : —
1. Form of a little chain: Torula, Leptothrix.
— The usual method of multiplication among the
bacteria is by fission (" scissiparite") ; each cor-
puscle divides transversely, and gives birth to two
44 MORPHOLOGY OF THE BACTERIA.
new individuals, which sometimes become sepa-
rated completely the one from the other, to form
unicellular bacteria, sometimes remain united; and
segmentation again occurring in each portion, a
chain is formed of articles more or less numerous.
When these chains are formed of spherical bac-
teria, they have been called torulce ; if they are
formed of filiform bacteria, they correspond to
leptothrix (Robin). The morphological difference
between the torula and the leptothrix consists in
the fact that in the first the articles are separated
by constrictions, while this is not the case in the
second. It is also to be remarked, according to
Cohn, that the microbacteria never take either
of these forms. Warming states, however, that
he has met the torula form in Bacterium lineola,
B. catenula, and B. termo (?).
Billroth has called these two forms of bacteria
streptococcos and streptobacteria. He has even
considered it necessary to create the words diplo-
coccos and diplobacteria for organisms constituted
only of two articles.
Z.^Foj^m of Zooglcea. — Generally, when bacte-
ria are rapidly multiplying, they remain grouped
in masses, swarms, or Zooylcea. In the latter con-
dition, they are closely pressed against each other
in the midst of a viscous substance, hyaline, ho-
mogeneous, colorless, and constituting masses
more or less diffused or definite, in irregular
globes, bunches, or tubes, swimming in the water
or near its surface. When the bacteria multiply
abundantly, the cells become removed from each
ORGANIZATION OF THE BACTERIA. 45
other, so as to leave between them greater inter-
vals. The masses sometimes attain a diameter of
several centimetres.
The gelatinous substance in which the bacteria
are included seems to be produced by a thicken-
ing and jellification of this cell-membrane, or by a
secretion from their protoplasm, but the latter
view seems more plausible than the former (De
Lanessan).
It is commonly the spherical bacteria (Micro-
coccus) and the microbacteria (Bacterium) which
are found in this state.
The filiform bacteria and the spirilla are never
found in gelatinous masses (Cohn). Kay-Lankes-
ter, however, claims to have met the Spirillum
tenue, in the form of zoogloea, and Klein the Spi-
rillum undula and rosaceum (Warming).
The form of Zoogloea , properly so called, gelat-
inous and thick, has never been found by Warm-
ing in infusions of sea-water.
According to the terminology of Billroth the
zooglcea are called gliacoccos and glidbacteria
(from yXi'a, mucus substance).
3. Form of My coder ma. — In certain cases, the
bacteria unite on the surface of the water, or of
the liquid in which they are developed, to form a
thick layer, a sort of membrane. This production
called mycoderma by Pasteur is a sort of zooglcea,
but differs from it by the absence of the interme-
diary mucous substance. The bacteria are, how-
ever, motionless, although living, since they come
to the surface to be in contact with oxygen, which
is necessary to them.
46 MORPHOLOGY OF THE BACTERIA.
The petalococcos and petalobacteria of Billroth
correspond with the mycoderma of Pasteur.
4. Swarms. — We have seen that the filiform
and spiral bacteria do not, usually, form zooglcea.
These microphytes are either disseminated and free,
or united in swarms. This formation may be seen,
for that matter, in all the bacteria, when, thanks
to abundant nourishment, they multiply rapidly
and gather together in considerable masses. They
are very active in these swarms, whilst in the
zooglcea the corpuscles are motionless, because of
the intermediary glairy substance.
Pulverulent precipitate. — When the nutritive
elements are exhausted in a liquid, the bacteria
cease to multiply, fall to the bottom of the recep-
tacle, and the liquid gradually becomes clear. The
deposit formed in this manner may acquire a thick-
ness very appreciable to the naked eye. The bac-
teria which form this precipitate are not dead, but
in a state of temporary repose ; and if a new sup-
ply of nutritive material is added to the liquid,
they are seen to multiply anew, until this has been
exhausted (Cohn).
PLATE n.
tfC> •'
^V * "' *•***/»* • - 1^
'tW
FIG. i.
FIG. 5.
PLATE II.
DIFFERENT MODES OF GROUPING.
Photo-micrographs by Dr. Sternberg.
FIG. 1. — Torula form of spherical bacteria (Micoderma aceli
Pasteur) from rotten banana, New Orleans, April, 1880. X 1000
diameters by Zeiss's ^ in. objective.
FIG. 2. — Zooyloea ramiqera from surface of foul gutter-water.
Baltimore, 1880. X 1000* diameters.
FIG. 3. — Zooglaaform of spherical bacteria developed in culture-
cell containing- blood of leper. X 600 diameters.
FIG. 4. — Mycoderma, from surface of foul gutter-water. New
Orleans, April, 1880. X 400 diameters by Beck's i in. objective.
FIG. 5. — Leptothrix chain of Bacilli (B. w?na°?) from putrid
blood of yellow-fever patient obtained post mortem. X 3000 diam-
eters. (Seep. 261).
CHAPTER II.
CLASSIFICATION OF THE BACTEKIA.
§ 1. — POSITION OF THE BACTERIA.
THE place of the bacteria in the scale of beings,
for a long time undetermined, demands to be
established with precision ; not only for the natu-
ralists, who only view the question from a system-
atic point of view, but above all for the biologists
who study the role of these organisms in the chem-
ical or pathological phenomena with which they
are associated. According to Ch. Robin, not to
define the animal or vegetable nature of these
organisms, " is for them as grave as it would be for
a chemist to leave undecided the question as to
whether it was nitrogen or hydrogen, urea or
stearine, which he had obtained from a tissue, or of
which he is following the combinations in certain
operations."
This determination is, to-day, possible ; and, if
there are still some differences of opinion among
naturalists as to the place of the bacteria among
the cryptogams, there is but one opinion as to
their vegetable nature.
It is surprising to see a savant like M. Pasteur
" not to pronounce positively upon the vegetable
CLASSIFICATION OF THE BACTERIA. 49 •
or animal nature of several of the ferments which
he has studied," and of which some belong to the
bacteria.
We shall first indicate rapidly the characters
which permit us, at first, to recognize certain spe-
cies of bacteria as organized beings, to determine
if they are animal or vegetable, and finally to
classify them either among the algae or among the
fungi.
Distinction of Bacteria from Inorganic Sub-
stances. — The question as to whether bacteria are
organized beings can only be raised in relation to
the smallest species, those Micrococci which are
scarcely perceptible with the highest powers ; the
organized nature of the other organisms of the
same group has never been questioned, even by
the earliest observers, who all, since Leeunhoeck,
have, without exception, taken them for animals
or vegetables. But the smallest forms of bacteria
may be confounded with various matters, with
organic particles, molecular granules, fat globules,
etc. " These productions, which are found in con-
siderable quantity in the liquids or in the tissues
of animal or vegetable origin, often resemble so
closely, in form, size, and grouping, the spherical
bacteria, that it is absolutely impossible to guard
one's self against confusion, unless the most mi-
nute precautions are taken in making the observa-
tions " (Cohn).
The detritus, the amorphous powder of precipi-
tated molecules of inorganic substances, even when
50 MORPHOLOGY OF THE BACTERIA.
they exhibit the brownien movement, are easily
enough distinguished from fificrococci by optical
signs, their angular form, their less refractive
power, and finally by their reaction with certain
chemical agents; above all if they are mineral
substances, crystalline bodies, etc.
It will not be the same with molecular granules
of organic nature. They have as common charac-
ters, their rounded form, their notable refractive
power, movements. Nevertheless, their form is
less regular, more angular, their color variable, their
refractive power always less. In doubtful cases,
Tiegel has given a method which enables us to dis-
tinguish them from Micrococci. It consists in
warming the glass slide which supports the cor-
puscles under examination ; if they are " Cbccos,"
they are seen to move in a manifest manner.
This does not occur in the case of molecular gran-
ules.
It is these productions which render it very
difficult to observe the phenomena which occur
during the coagulation of milk. The caseine sep-
arates in the form of extremely minute globules
"having a very rapid molecular movement. But
we may distinguish these from bacteria by the
use of liquor potassse, which dissolves the former
without attacking the latter.
As another example of pseudobacteria, I will
mention, after Cohn, the form which fibrine as-
sumes when it separates from the plasma of the
blood. It disposes itself in very slender filaments,
closely resembling filamentous bacteria.
CLASSIFICATION OF THE BACTERIA. 51
Fat globules, which are found of all sizes, are
often of the same dimensions as Micrococcus, and
are very difficult to distinguish from the latter.
The difference in refractive power is slight, and
the action of re-agents, such as ether, is not cer-
tain in mucilaginous solutions. Hiller, who has
paid especial attention to the means of recognizing
bacteria, divides them into two groups : —
A. The optical signs: comprising 1. The charac-
teristic vegetable form, rods, leptothrix, this he
recognizes as of little use, as in this case there is
no doubt; 2. The characteristic movements of the
monads; 3. The mode of growth and of multipli-
cation ; 4. The mode of junction of the granules.
B. The chemical signs : 1. False zooglcea become
softened and diffluent under the action of liq.
potassse, and are coagulated by the direct applica-
tion of alcohol ; 2. In sections of tissues, after an
hour of maceration in liq. potassse, diluted -^th,
the monads are colored brown by iodine, while fat
granules are not.
But, in truth, the method of cultivation, ex-
tolled by Cohn and Wolff, is the best means of
distinguishing the bacteria. " The distinction of
pseudobacteria," says the first of these authors,
" from veritable globular bacteria is a problem
which our microscopists cannot resolve, in every
case, with the desirable certainty. It is only by
a study of their mode of development that this
distinction can be made. The globules which di-
vide and develop in form of chains are organized
beings ; when this does not occur, we are dealing
with pseudobacteria."
52 MORPHOLOGY OF THE BACTERIA.
This is not, however, exactly the opinion of
Nageli, who seems to consider movement as the
surest distinctive characteristic.
" There are," he says, " but three distinctive
signs which enable us to recognize with some
certainty that granules under observation are or-
ganisms, — spontaneous movement, multiplication,
and equality of dimensions, united with regularity
of form.
"The most certain character is movement in
a straight or curved line, — a movement which
inorganic granules never present. One should
take care not to be deceived by movements
which are caused by currents in the liquid under
observation. Nor should one allow himself to be
deceived by the tremulous motion, called molecu-
lar movement, in which the granules do not really
change their position. These movements are seen
in most cells, and even in those of the Schizomy-
cetes, and inorganic bodies themselves present it.
" Multiplication is a character less important
than movement. When among granules some
are found united in pairs, it may be supposed
with probability that division and multiplication
are taking place. When rods are bent at an angle,
one may predict their division in two parts.
" Finally, as to size and form. Granules of dif-
ferent size and of a more or less irregular form
ought not to be considered as belonging to the
group of segmented fungi ; if, on the contrary,
the granules offer dimensions perfectly equal, and
a spherical or oval form, the distinction is more
CLASSIFICATION OF THE BACTERIA. 53
uncertain : they may belong to the schizomycetes
or be of inorganic nature."
Place of the bacteria among organized beings.
Distinction between animals and vegetables. — The
characters which serve to distinguish the inferior
animal organisms from the inferior vegetable or-
ganisms are of two orders, optical and chemical.
A. The optical characters are drawn from the
general form, the movements, and the mode of
reproduction.
The morphological characters have no value
except among the larger species of bacteria. If
we bring together a Spirillum and &Spindina,
Kiitz., their affinities will be apparent to every
one. It is not the same for the large species of
Bacillus, of which the relations with the Oscilla-
toria are evident. The rod form seems very spe-
cial, but it does not necessarily imply the vege-
table nature of the organisms which possess it.
Finally, the spherical bacteria, — Monas and Mi-
crococcus, — resemble entirely by their form some
infusorial animals.
Movement is not a more special character. It
is now well proved that it does not belong exclu-
sively to animals, and that it is met with in a cer-
tain number of the inferior vegetables.
In fact, the anatomical characters are not al-
ways absolutely reliable ; but it is from these
alone that Cohn first, then Davaine, have recog-
nized the bacteria as vegetables.
B. Chemical characters. Robin depends upon
54 MORPHOLOGY OF THE BACTERIA.
these characters to demonstrate the vegetable na-
ture of the bacteria. He takes for point of de-
parture the notions of general physiology as given
by De Blainville in the following points : —
1. We find in animals various elementary sub-
stances of the same kind as in plants, and re-
ciprocally.
2. The ternary compounds predominate., how-
ever, in plants ; and the quarternary, nitrogenized,
are more abundant, on the contrary, in animals.
3. In both, the fundamental cellular structure
is the same ; at least originally for the greater
number, and always in the most simple of organ-
ized beings, etc. . . .
" It results from this, then," continues M. Kobin,
" that so long as there is no digestive tube one
can only distinguish plants from animals by the
study of their elementary principles, and of the
chemical reactions which these exhibit in general ;
by the study, in particular, of the reactions which
the predominance of ternary cellulose principles
over all others gives to plants, and that of nitro-
genized principles in animals, at all periods of
their existence."
Starting from this basis, Robin made numerous
attempts to find in liquor ammonia, concentrated,
as prepared for use in laboratories, a reagent for
corpuscles of a vegetable nature. In effect, am-
monia dissolves the eggs, the embryos, of all ani-
mals, the bodies of all the inferior infusoria,
attacks the spermatozoa, etc., whilst it leaves ab-
solutely intact all the varieties of cellulose and
CLASSIFICATION OF THE BACTERIA. 55
the anatomical reproductive elements of plants,
whether it is used cold or boiling.
As to the other chemical characters praised
during recent years, we will content ourselves
with mentioning concentrated acetic acid, which
causes all animal tissues to become pale, whilst it
is without action on bacteria (Luckonvsky) ; io-
dine, and sulphuric acid (Letzerich), etc.
Hematoxyline (Luckonvsky) and fuchsin (Hoff-
mann) color the bacteria deeply. One ought, then,
no longer to give to the bacteria, as do some
recent authors, the names of microscopic ani-
malcules, — infusoria, microzoa, etc., and other
expressions without precision, or consecrating an
error.
Let us add that some naturalists of high re-
pute, Hackel for example, have created for these
minute beings, monera, protoplasts, flagellata, dia-
toms, etc., an intermediary kingdom between the
animal and vegetable, — the Protista.
Place of the Bacteria in the Vegetable Series. —
The vegetable nature of the bacteria once estab-
lished, it remains now to determine to what class
of vegetables they belong.
Are they algae, or are they fungi ? This is the
question which divides the naturalists.
It is true that it is to-day very difficult to find
a characteristic of these two classes of vegetables,
both having, in a general manner, identical forms,
similar reproductive apparatus, etc. ; and, if it is
impossible to confound a Basidiomycete with a
Floridese, for example, it is not the same when
56 MORPHOLOGY OF THE BACTERIA.
one studies the inferior species. The only char-
acter which appears general is the presence of
chlorophyll in the algae and its absence in the
fungi. But, if we adopt this distinctive character,
and apply it in all its rigor, we are obliged to
separate in the inferior algae some forms very
nearly related, and which do not differ from their
relations except in this particular. And this is ex-
actly what happens in the case of the bacteria.
In truth, the bacteria, although entirely with-
out chlorophyll, have numerous affinities as to
form, movement, etc., with the osciUatoriacece,
and, according as one or the other of these char-
acters have appeared to predominate, the bacteria
have been classed as algae or as fungi.
It is thus that Davaine, Rabenhorst, then Cohn,
struck above all by the resemblance of form, mode
of grouping, and of multiplication, have placed
the bacteria among the algae. Cohn insists, above
all, upon the affinities of the filiform bacteria with
the beggiatoa and the leptothrix ; of the micrococ-
cus, and of the bacterium, with the chroococcacece.
He at first placed them at the commencement of
this last series ; but we shall see further on that
in his last publications he has disseminated them
among the oscillatoriaceae and the chroococcaceae.
Robin and Nageli, on the other hand, insist
rather upon the affinities of the bacteria with the
yeast plants, which are incontestably fungi, and
they include them in this class.
Robin says expressly : " All the corpuscles de-
scribed under the name of Bacterium termo, B.
CLASSIFICATION OF THE BACTERIA. 57
punctum, etc.. Zooglcea, Micrococcus, and many
others, are vegetable cells, spores of fungi, of sev-
eral distinct species certainly; spores, or repro-
ductive bodies of the first order, derived one from
another, either by germination, fission, or from a
mycelium ; reproductive bodies, in a word, of the
order of those which Tulasne has arranged under
the name of conidia, etc."
Nageli establishes in the inferior fungi which
produce decompositions three very natural groups.
1. The Mucorini, or mould fungi ;
2. The Saccharomycetes, or budding fungi, which
produce the fermentation of wine, beer, etc. ;
3. The Schizomycetes, or fission fungi, which pro-
duce putrefactive processes. This last group is formed
of our bacteria (Micrococcus, Bacterium), etc.
Sachs solves the question by uniting the algae
and fungi in a single group, the thattophytes, in
which he establishes two series exactly parallel, —
one comprising the forms with chlorophyll ; the
other, the forms which are deprived of it, and
preserving in a transverse direction the morpho-
logical affinities of these organisms.
As this classification is yet but little known, we
think it best to give it in the following table : —
THALLOPHYTES.
Forms with chlorophyll. Forms without chlorophyll.
CL. 1. PEOTOPHYTES.
* A. Cyanophycese (Oscil- A*. Schizomycetes (Bac-
latoiiacese, etc.). teria).
B. Palmellaceae. B'. Saccharomycetes
(Ferments).
PLATE III.
Bacillus subtilis and spores of bacilli. Photo-micrographs by Dr.
Sternberg.
FIG. 1. — Spores of B. subtilis and micrococci, from surface
culture on gelatine and beef peptone. X 500 diameters.
FIG. 2. — Development of bacilli from spores, from culture ex-
periment with fish gelatine solution. X 1,500 diameters by Zeiss's
^ in. objective.
FIG. 3. — Spores of Bacillus developed in rotten potato, New
Orleans, April, 1880. X 1,500 by Zeiss's ^ in. objective. The
large cells are some species of Saccharomycete, which was also
present in the same specimen.
FIG. 4. — Bacillus (B. ulna} containing a single spore at one ex-
tremity ; from putrid blood (of yellow- fever patient) obtained post
mortem. X 3000 diameters.
FIG. 5. — Bacillus subtilis, from surface of beef -peptone culture-
solution. X 500 by Zeiss's £ in. objective (D. D., dry); Balti-
more, 1884.
PLATE in.
FIG. i
FIG. 2.
CLASSIFICATION OF THE BACTERIA. .59
CL. 2. ZYGOSPOREJE.
A. Volvocinese. A'. Myxomycetes.
B. Conjugueae and Dia- B'. Zygomycetes.
toms.
CL. 3. OOSPOREJE.
A. Sphseroplese.
B. Cceloplastese. Saprolegnise.
C. (Edogonise. Peronosporese.
CL. 4. CARPOSPORE.E.
A. Coleochsetese. A'. Ascomycetes.
B. Floridese. B'. GEcidiomycetes.
C. Characese. C'. Basidiomycetes.
Our preferences are for this last mode of classi-
fication, but obliged, in the description of species,
to follow the classification of Cohn, the most com-
plete which has been given hitherto, we must
abandon it for the present.
§ 2. — CLASSIFICATION ; GENERIC AND SPECIFIC
CHARACTERS.
The numerous classifications of the bacteria of
which we have given an abstract in the historical
part of this work, show how variable have been
the ideas of the microscopists as to the nature of
these organisms.
Before giving the most recent, those among
which we will have to choose, it is best to study
the characters upon which authors have depended
for grouping the bacteria in genera and species,
and to estimate the value of these characters.
60 • MORPHOLOGY OF THE BACTERIA.
1. Generic and specific characters. — These have
been drawn from the dimensions, form, movement
and evolution of the bacteria.
The size, which, according to Cohn, is the dom-
inating distinctive character, is often indetermi-
nable, even in employing the highest powers.
Besides, for a great number of neighboring forms,
the differences of measurement given as distinctive
are so slight that they cannot serve in practice.
Thus, according to Dujardin, the Bacterium termo
has a length of 1.7 /A, and iheJB.punctum of 1.7 to
0.6 JJL. Another difficulty presents itself when we
examine bacteria formed of several articles. Shall
we consider the length of a single article or of the
chain, which consists of a number of articles, a
number ordinarily variable ?
The form of the bacteria and their union in
colonies, also offer differences, which have been
utilized ; but do they depend upon differences truly
specific, or do they come from foreign influences,
from phases of development of the same organism?
Even when one uses these as distinctive specific
characters, the form is sometimes of little assist-
ance ; since if one refers to the descriptions of
Dujardin, the Bacterium termo will be found to have
a cylindrical body swollen in the middle, and the
B. punctum an elongated ovoid body.
As to movement, we have seen that the phenom-
ena of mobility or of immobility sometimes pre-
sent themselves in the same species, according to
age or changes in the medium.
We have left, the mode of development, the
CLASSIFICATION OF THE BACTERIA. 61
phenomena of reproduction by fission or by
spores, as the only character which can serve to
establish our natural genera; but, unfortunately,
this has only been ascertained for a small number
of bacteria, the Bacillus anthracis, for example.
The genera of bacteria cannot have the same
significance as among animals and superior vege-
tables ; they can only be established in accordance
with the most prominent characters, reserving the
feeble modifications of these generic forms as
specific characters.
Are there distinct, well-defined) species among
the Bacteria f
The microscopists have given the most diverse
opinions upon this subject. Miiller, Ehrenberg,
Dujardin, Davaine, have admitted the specific dis-
tinction of the numerous vibrioniens which they
have described. Davaine, however, raises some
doubts as to the absolute value of the species
established in his time. " Those which are de-
scribed to-day by the classifiers," he says, " ought
to be considered as the expression of types under
which are hidden a certain number of distinct
species."
Cohn dwells still more upon the impossibility,
in which we are to-day, of distinguishing with
certainty genera and species among the bacteria.
However, he is convinced that the bacteria are di-
vided into species as distinctly as the other plants
and inferior organisms. It is only the imperfection
of our means of observation which makes it impos-
sible to recognize these differences. This is above
62 MORPHOLOGY OF THE BACTERIA.
all true, he says, of the spirilla, which are not only
distinguished from the rod bacteria, properly so
called ; but which present in their species some
differences as constant as any well-defined species
of alga or of infusoria.
Hallier, Hoffmann, Billroth, Robin, Nageli, etc.,
consider the different forms of bacteria in a very
different fashion. According to them they are
not autonomous species, but phases of development
of one or of several species.
According to Hallier, we may see, a propos of
the polymorphism of the bacteria, the singular
transformations which he has obtained by their
cultivation.
-According to Billroth, the bacteria belong to a
single species of plants, the Coccobacteria septica,
with the exception of the Spirillum and Spirochceta,
in regard to which Billroth is not willing to give
an opinion. This view has been adopted by a
certain number of microscopists, and above all by
the pathologists, such as Frisch, Tiegel, etc.
Robin also admits the genetic relation of Micro-
coccuSj Vibrio, Bacterium and Leptothrix, but con-
siders them the distinct and successive phases in
the evolution of several species : 1st. Corpuscles
described under the name of Bacterium termo,
punctum, etc., Micrococcus ; 2d. Mycelial fila-
ments, Vibrio, etc. ; 3, Bacteria, Bacteridies, Micro-
bacteria, etc. ; 4th. Leptothrix and forms more
advanced.
The opinion of Nageli corresponds very nearly
with the preceding. " As much as I am con-
CLASSIFICATION OF THE BACTERIA. 63
vinced," he says, " that the schizomycetes cannot
be grouped in accordance with their action as fer-
ments and their exterior forms, and that altogether
too many species have been distinguished ; so, on
the other hand, it seems to me very improbable
that all the schizomycetes constitute a single natu-
ral species.
" I am rather inclined to suppose that there exists
among them a small number of species, which
have little in common with the genera and species
admitted to-day, and of which each runs through a
cycle of determined forms sufficiently numerous.
Each of the veritable species of schizomycetes is
not limited to presenting itself under the different
forms of Micrococcus, Bacterium, Vibrio, and Spi-
rillum, but can also show itself as the agent of
acidification of milk, of putrefaction, and as the
agent producing several maladies." However,
Nageli recognizes that it is necessary to distin-
guish these forms, notably those of Micrococcus,
Vibrio, Bacterium, and Spirillum, without, how-
ever, losing from view the fact that the organisms
thus classified have a very inconstant constitution,
and pass continually from one form to another.
Finally, other savants such as M. Pasteur, take
less account of the structural characters than of
the physiological functions, regarding as a partic-
ular species every form of bacterium .which is born
constantly in a determined medium, or which
causes a special kind of fermentation.
Nageli opposes to this view the following
objections. First, he has verified the presence, in
64 MORPHOLOGY OF THE BACTERIA.
the same decomposition, of several different forms
of schizomycetes. On the other hand, in decom-
positions quite different, we may observe schizo-
mycetes entirely similar as to their exterior form.
Finally, we may change the mode of action of a
schizomycete in subjecting it to a certain treat-
ment. One sees that it is truly difficult to form
an opinion as to the value of these species purely
physiological.
To sum up, the characters which may be used
in order to establish genera and species in the
group of the bacteria are of small number and of
very unequal value. Some, characters of form, of
dimension, of movement, etc., are often difficult to
determine, or have only a relative value ; others,
characters drawn from development and reproduc-
tion, are only known in so few species that they
cannot be made to serve as a basis of classifica-
tion.
One will not be surprised, then, to find that
there is no natural classification of the bacteria,
and that it is impossible for the naturalists to give
one. All those that can be established are pro-
visory, being only based upon the morphology of
these organisms. Following the example of all the
botanists, we will use an analogous classification,
but without wishing to prejudge in any particular
the genealogical relationship of the different or-
ganisms, which we shall consider as distinct gen-
era and species.
CLASSIFICATION OF THE BACTERIA. 65
§ 3. — CLASSIFICATION AND DESCRIPTION OF THE
GENERA AND SPECIES OF THE BACTERIA.
We have seen in the historical portion of this
work, a propos of the classifications which have
been given of the bacteria, that, in 1872, M. Cohn,
recognizing the numerous relations, absence of
chlorophyll, mode of nutrition, etc., which make
these organisms a natural family, divided them
into four tribes : —
1. The Spherobacteria, or spherical bacteria.
2. The Microbacteria, or B. in short rods.
3. The Desmobacteria, or B. in straight filaments.
4. The Spirobacteria, or B. in spiral filaments.
In the spherobacteria, Cohn has only adopted
one genus, the g. Micrococcus, of which the spe-
cies are divided into three series, — the pigmen-
tary M., or chrornogenes, the M. of fermentations,
or zymogenes, and the M. of contagious affections,
or pathogenes.
The microbacteria include only the genus Bac-
terium, with two species, B. termo, Dujardin, and
B. lineola, Cohn.
The desmobacteria comprehend the g. Bacillus
and Vibrio ; the first established by Cohn for the
rectilinear filaments is composed of the B. subtilis,
Cohn (with B. anthracis as a variety) and the B.
ulna, Cohn ; the second, characterized by undu-
lating filaments, is reduced to V. rugula and ser-
pens} Auct.
66 MORPHOLOGY OF THE BACTERIA.
Finally, the spiral filaments of the spirobacte-
ria characterize the gr. Spirillum and Spirochceta,
which might be united in a single genus compris-
ing Sp. plicatile, tenue, undula, and volutans.
Since then, Cohn, struck with the affinities
which each of the preceding genera presents with
several genera of oscillatoriacese and of chroococ-
ceae, from which the bacteria only differ by the
absence of chlorophyll, has established a class of
Schizophytes, which includes all the inferior vege-
table organisms, provided or not with chlorophyll,
multiplying by fission.
We give below the complete table : —
2. Classification of the Schizophytes, Cohn.
TRIBE 1. — GL^OGENES.
Cells free or united in glairy families by an intercellular substance.
A. Cells free or united by 2 or by 4 :
Cells spherical . . CHROOCOCCUS, Nag.
Cells cylindrical . SYNECHOCOCCUS, Nag.
B. Cells united in glairy families,
amorphous in state of
repose :
a. Cellular membrane, con
founded with the intercel-
lular substance :'
1. Cells without phyco-
chrome, very small :
Cells spherical . . MiCROCOCCUS, Hallier.
CLASSIFICATION OF THE BACTERIA. 67
Cells cjdindrical . BACTERIUM, Duj.
2. Cells with phyco-
chrome, larger :
Cells spherical . . APHANOCAPSA, Nag.
Cells cylindrical . APHANOTHECE, Nag.
I. Intercellular substance
formed of several mem-
branes enclosed one with- •
in the other :
Cells spherical . . GLCEOCAPSA, Kg.
Cells cylindrical . GLCEOTHECE, Nag.
C. Cells united in glairy fam-
ilies of definite form :
a. Families of a single layer
of cells disposed in plates :
1. Cells in fours form-
ing a plane surface . MERISMOPEDIA, Meyeii.
2. Cells without regular
arrangement, forming
a curved surface :
Cells spherical, fam-
ilies with reticu-
lated rupture . . CLATHROCYSTIS, Henfr.
Cells cylindrical, cu-
neiform, families
divided by con-
striction . . . CaSLOSPBLERITJM, Nag.
I Families with several lay-
ers of cells, united in spher-
ical corpuscles :
1. Number of cells de-
termined :
Cells spherical, col-
orless, arranged
in fours . . . SARCINA, Goods.
G8 MORPHOLOGY OF THE BACTERIA
Cells cylindrical, cu-
neiform, with phy-
cochrome, with-
out regular ar-
rangement . . GoMPHOSPH^EilA, Kg.
2. Number of cells very
great and indetermi-
nate :
Cells colorless, very
small .... Ascococcus, Billr.
Cells colored by
phycochrome
and larger . .
POLYCYSTIS, Kg.
COCCOCHLORIS, Spr.
POLYCOCCUS, Kg.
TRIBE 2. — NEMATOGENES.
Cells disposed in filaments.
A, Filaments not branched :
a. Filaments free or inter-
laced.
1. Filaments cylindrical,
colorless, articulations
not very distinct :
Filaments very slen-
der, short . . . BACILLUS, Cohn.
Filaments very fine,
long LEPTOTHRIX, Kg.
Filaments larger,
long .... BEGGIATOA, Trev.
2. Filaments cylindrical, \
with phycochrome,
articles well denned,
, OSCILLARIA, BOSC.
without cellular re- v
production . . .
HYPHEOTHRIX, Kg.
CLASSIFICATION OF THE BACTERIA. 69
3. Filaments cylindrical,
articulated, with co-
nidia :
Filaments colorless CRENOTHRIX, Colin.
Filaments with phy-
cochrome . . . CHAM^ESIPHON.
4. Filaments spiral
without phycochrome :
Filaments, short,
light, sinuous . VIBRIO, Ehr.
Filaments, short, spi-
ral, rigid . . . SPIRILLUM, Ehr.
Filaments, long, spi-
ral, flexible . . SPIROCH^TE, Ehr.
with phycochrome :
Filaments long, spi-
ral, flexible . . SPIRULINA, Link.
5. Filaments in chaplet :
Filaments, without
phycochrome . . STREPTOCOCCUS, Billr.
Filaments with phy- ) ANABJSNA, Bory.
cochroine . . . j SPERMOSIRA, Kg.
6. Filament flagelliform, .
slender MASTIGOTHRIX, etc.
b. Filaments united into glai-
ry families by an intercel-
lular substance :
1. Filaments cylindrical,
colorless MYCONOSTOC, Cohn.
2. Filaments cylindri-
cal, with phyco-
chrome
CHTHONOBLASTUS.
LlMNOCLIDE, Kg.
3. Filaments in chaplet . NOSTOC, etc.
4 Filaments flagelliform,
slender RIVULARIA, etc.
70 MORPHOLOGY OF THE BACTERIA.
B. Filaments with false ramifi-
cation :
1. Filaments cylindri- j CLADOTHRIX, Cohn.
cal, colorless . . ) STREPTOTHRIX, Cohri.
2. Filaments cylindri-
cal, with phyco-
. chrome . . .
CALOTHRIX, Ag.
SCYTONEMA, Ag.
3. Filament in chaplets . MERIZOMYRIA, Kg.
4. Filaments flagelli- J SCHIZOSIPHON) K
form.slender towards GEOCYC K
the extremity . . )
An inspection of this table shows that each of
the genera of the ancient group of the bacteria
has been placed beside some genus of oscillatori-
aceoe, which it resembles by its organization, —
Micrococcus and Bacterium, beside Aphanotkece
and Aphanocapsa ; Bacillus, beside Leptothrix
and Beggiatoa ; Vibrio and Spirillum, beside Spi-
rulina.
These affinities are undeniable, and the advan-
tages of such a classification are manifest ; but, in
a work like this, we cannot think of employing it.
We preserve, then, in a distinct group the schizo-
phytes deprived of chlorophyll, which may be
arranged in the four primary divisions of Cohn
with the exception of Sarcina, Ascococcus, Creno-
thrix, etc., and the other genera created recently
by this botanist.
Thus we will describe successively : —
1. The Spherobacteria of Cohn; and beside them
the different Monas recently studied, — the Micrococ-
CLASSIFICATION OF THE BACTERIA. 71
cus described by Hallier in several infectious mal-
adies.
2. The Microbacteria.
3. The Desmobacteria, including Bacillus, Lepto-
thrix, Beggiatoa, and Crenothrix.
4. The Spirobacteria, including the three genera,
Vibrio, Spirillum, and Spirochceta.
5. Finally, we will give some account of the Mer-
ismopedia, Sarcina, Ascococcus, Streptococcus, Myco~
nostoc, Cladothrix, and Streptothrix.
1. SPHEROBACTERIA, Cohn.
The spherical bacteria are characterized by their
rounded or oval form, their small size, often less
than 1 fji. They are ordinarily isolated, often in
pairs (diplococcus), sometimes in a chain of several
articles (streptococcus = torula of Cohn), the my-
cothrix of Hallier and Itzigsohn, or in the form of
zooglcea when they are young and actively multi-
plying, and that of mycoderma, when they are
gathered upon the surface of liquids. They have
no spontaneous movement, but a simple molecular
trepidation.
Functions : " The spherical bacteria are fer-
ments, not producing putrefaction, but substitu-
tions of another kind" (Cohn).
Obs. According to the facts observed by Koch,
Cohn, Pasteur, Toussaint, upon the development
of certain bacteria, it is very probable that some
at least of the spherobacteria are spores of Bacil-
lus or of other bacteria; at least, the micrococci
and these spores are identical in form and aspect.
72 MORPHOLOGY OF THE BACTERIA.
The spherobacteria include only the genus Mi-
crococcus.
g. Micrococcns, Cohn (Hallier emend. — Micro-
sphceria, Cohn. ante).
Cells colorless, or scarcely colored, very small,
globular or oval, forming by transverse division
filaments of two or several articles, in form of
chaplet, or united in numerous cellular families,
or in gelatinous masses, all deprived of move-
ment.
The species are divided into three physio-
logical groups : —
a. M. Chromogenes.
b. M. Zymogenes.
c. M. Pathogenes.
SECTION (A) : MICROCOCCUS CHROMOGENES.
The pigmentary bacteria grow in the state
of Zooglcea upon the surface of the substances
which furnish them with nutriment. They are
always alkaline ; all are avid of oxygen ; their
morphological characters are identical, and one
can only distinguish them by their different
coloring properties.
According to Cohn, they are veritable spe-
cies ; for 1. Their pigments offer the greatest
diversity as to chemical action and by spectro-
scopic analysis, etc. ; 2. Each species cultivated
in the most diverse media produces always the
same coloring matter.
CLASSIFICATION OF THE BACTERIA. 73
They are divided into two categories, accord-
ing as the pigment is soluble or not in water.
1. Coloring matter insoluble.
M. Prodigiosus, Cohn (Monas prodigiosa, Ehrb. ;
— Palmella prodigiosa, Mont. ; — Bacteridium
prodigiosum, Schrceter).
A red gelatinous mass, pink carmine, develop-
ing upon cooked alimentary substances placed
in damp air, never before cooking.
It has also been observed in red milk, at-
tributed incorrectly to lesions of the teats,
etc. (Cohn).
M. luteus, Cohn (Bacteridium luteum, Schroeter).
A yellow gelatinous mass studied by Schroeter
and Cohn upon potatoes.
2. Coloring matter, soluble.
M. aurantiacus, Cohn (Bacteridium auriantiacum,
Schrceter).
Little drops, or stains, more or less extended,
golden yelloio, cultivated by Schrceter, upon
slices of cooked potato; by Cohn, upon hard
white of egg.
M. chlorinus, Cohn.
A glairy yellowish-green pigment found upon
hard white of egg, not reddened by acids, but
loses its color.
M. cyaneus, Cohn (Bacteridium cyaneum, Schroe-
ter).
Pigment deep blue, observed by Schrceter
74 MORPHOLOGY OF THE BACTERIA.
upon cooked potato, and cultivated by Cohn in
nutritious solutions. This coloring matter is
reddened by acids, and restored to blue by al-
kalies, just as that which forms when lichens
are macerated in presence of ammonia.
M. violaceus, Cohn (Bacteridium violaceum, Schroe-
ter).
Violet-blue masses or glairy stains formed of
elliptical corpuscles larger than those of M.pro-
digiosus, observed first by Dr. Schneider, then
by Schrceter on cooked potato.
Later, Cohn has described the two following
new species (1876), which should be included in
this group :
M. Candidus, Cohn.
Stains and points ichite as snow, observed
upon slices of cooked potato.
M. fulvns, Cohn.
Little rust-colored drops, consisting of cells,
globular or united in pairs, in a tenacious inter-
cellular substance, diameter 1.5 /*, observed by
Eidam, then by Kirchner, upon horse dung.
It is also to the genus Micrococcus that we
must refer the little globular bacteria, gifted
with movement, found by Eberth in white, yel-
low, and red perspiration, and by Chalvet in the
pus on the edges of certain wounds, but which
should not be confounded with the blue color
produced by a Bacterium.
CLASSIFICATION OF THE BACTERIA. 75
SECTION (B): MICROCOCCUS ZYMOGENES.
Globular bacteria producing fermentations of
diverse nature.
M. crepusculum, Cohn (Monas crepusculum, Ehrb.).
Globular cells, colorless, developing in all in-
fusions of animal and vegetable matter under-
going decomposition.
M. ureae, Cohn.
Oval cells, isolated, diameter 1.5 \L (Pasteur),
1.2 to 2 p, (Cohn) or united by 2, 4, to 8 (to-
ruld), in a line, straight, curved, zigzag, or even
in cross form. In urine, of which it transforms
the urea into carbonate of ammonia (Pasteur).
A Torula which appears identical with the
preceding Micrococcus, produces the decomposi-
tion of hippuric acid into benzoic acid and gly-
collamine (Van Tieghem).
M. of -stringy wine, etc.
Globular cells of 2 ^ diameter, in chaplets,
found in stringy wine, perhaps identical with
the preceding (Pasteur).
A Torulacese quite similar is found in certain
fermentations of tartrate of ammonia and of
beer yeast, with or without the addition of car-
bonate of potash (Pasteur).
SECTION (c): MICROCOCCUS PATHOGENES.
Spherical bacteria found in affections of a con-
tagious nature.
76 MORPHOLOGY OF THE BACTERIA.
M. vaccinae, Cohn (Microsphcera Vaccince, Colin).
Very small micrococci, = 0.5/1 scarcely, iso-
lated or united in pairs in recent vaccine virus
and in the pus of variola pustules. By cultiva-
tion, chaplets of from two to eight cells may be
obtained, then masses containing sixteen to
thirty-two cells of 10 /x and more diameter.
The M. of vaccine virus and of variola are
identical, and Cohn regards them as different
races of the same species.
M. diphtheriticus, Cohn.
Granular cells, ovoid, measuring from 0.35 to
to 1.1 ft, isolated or more often united in twos
or in a chaplet of four to six cells ; sometimes
multiplying in colonies and extending them-
selves in all the diseased tissues, decomposing
and destroying them ((Ertel).
M. septicus, Cohn (Microsporon septicus, KlebsJ.
Little rounded cells, of 0.5 /x, motionless and
crowded in masses or united in chaplets, in the
secretion of wounds in cases of septicemia
(Klebs), in zooglcea in callous ulcers, in isolated
cells, united in pairs, or in chaplets in the se-
rum of epidemic puerperal fever (Waldyer), in
all the tissues, vessels, etc., in cases of pyemia
and septicemia.
M. bombycis, Cohn (Mycrozyma bombycis, Be-
champ).
Cells with a diameter of 1 ^ ordinarily united
in chaplets of two, three, four, five, or more, in
CLASSIFICATION OF THE BACTERIA. 77
the intestine of silkworms sick with " la flach-
crie " (Pebrine).
In a more recent work, Colin (Beitrage, 1875,
p. 201) gives them an oval form and a diameter
of 0.5 [M at the outside.
We omit in the present edition the various pathogenic
Micrococci described by Hallier, and introduce in place of
them several species (?) which have been studied by more
recent authors, and which seem to be better established.
(G. M. S.)
M. of erysipelas, Fehleisen.
Ver}' minute (smaller than the micrococci of vaccinia) ,
found in zoogloea masses in the lymphatics of the skin at
the margin of the zone of redness in extending erysipela-
tous inflammation.
M. of pneumonia (?), Friedlander.
Large oval micrococci, surrounded by a transparent
capsule, 1 n in length, in pairs, short chains or zooglcea
masses, in the sputum of croupous pneumonia during the
early stages of the disease.
M. of induced septicaemia in rabbits, Sternberg.
Oval micrococci, surrounded by a transparent aureole of
mucus ( ?) material, about 1 fi in length, and found solitarj',
in pairs, and in short chains, in the blood and sub-cutane-
ous oxlema of rabbits killed by the sub-cutaneous injection
of normal human saliva.
M. of fowl cholera, Pasteur.
Micrococci, 0.5 /A in diameter, mostl}' in pairs (figure 8)
in the blood and tissues of fowls affected with fowl
cholera.
78 MORPHOLOGY OF THE BACTERIA.
M. of swine plague (rouget ou mal rouge des pores) ,
Pasteur.
Said by Pasteur to closely resemble the microbe of fowl
cholera, but to be smaller and less easily seen. Klein
ascribes this disease to a bacillus.
M. of gonorrhoea (.?), Neisser.
Found in pairs or in sarcina-like groups of four in gon-
orrhoeal pus, invading the pus corpuscles, and the epithelial
cells from the urethra.
M. of infectious osteomyelitis (?).
Found by Becker in pus from unopened abscesses in five
cases of acute osteomyelitis. Not to be distinguished by
its morphological characters from the micrococcus found
in the pus of acute abscesses generally.
M. of progressive necrosis in mice, Koch.
Micrococci 0.5 ^ in diameter, in chains and zoogloea, in
necrotic tissues of mice injected with putrid fluids.
MONADS.
Beside the Spherobacteria are placed the Mon-
ads, not the organisms described under this name
by the older microscopists, comprising micro-
phytes, spores, and infusorial animals, but the
Monas as understood by botanists of the present
day. Thus limited, the Monads include also, be-
sides some microphytes related to the Sphero-
bacteria, and differing from them by their greater
dimensions, some organisms of doubtful affinities.
CLASSIFICATION OF THE BACTERIA. 79
As in the case of the Micrococd it is very
probable that the Monads are only the spores, or
lower forms of bacteria higher in the scale. Cohn
places the Monas vinosa of Ehrenberg with the
Clathrocystis roseopersicina, Cohn (Bacterium ru-
bescens, Ray-Lank.), considering it a spore of the
latter.
Monas vinosa, Ehrb.
Cells spherical, oval, regular, of 2.5 yu,, often united
in pairs, formed of a pink substance with granules of
a deeper color, having spontaneous movements, ffab.,
waters containing decomposing vegetable matters
(Ehrb. 1838, Ch. Morren 1841, Perty 1852, Cohn
1875).
M. Okenii, Ehrb.
Cells cylindrical ; average length 7 to 15 p (Cohn),
10 fj, (Ehrb.), sometimes from 60 to 80 p (Warming),
diameter 5 //, ; of a beautiful red color, having a rapid
gyratory movement, with a cilium at the posterior
extremity or two cilia at the two extremities. Hob.,
stagnant water (Ehrb. 1836, Eichwald, Weiss, Cohn,
etc.).
M. Warmingii, Cohn.
Cell cylindrical, pink, containing at its two rounded
extremities some deep-red granules; length 15 to
20 /z, width 8 p ; movement uncertain, having a vi-
bratile cilium. Hab., brackish water on the coast
of Norway (Warming).
M. gracilis, Warming.
Cells straight, cylindrical, pink, rounded at the
two extremities ; length 60 p, thickness 2 //, ; move-
ment slow. Hal.) fresh water.
80 MORPHOLOGY OF THE BACTERIA.
Ehdbdomonas rosea, Cohn.
Cells pale pink, isolated, fusiform ; eight times as
long as broad, having a length of 20 to 30 //,, and a
width of 3.8 to 5 fi; having a slow oscillatory move-
ment, the pink substance containing numerous gran-
ules of darker color and vacuoles. Hob., stagnant
water.
Ophidomonas sanguined, Ehrb.
Cells pale pink, spiral, rigid, movement active ;
thickness 3 /LI, length of one turn of the spiral, 9 to
12 //,. jETa6., brackenish waters of Denmark (Warm-
ing)-
Spiromonas Cohnii, Warming.
Cells spiral, flattened; 1J turn of spiral, diam. 1.2
to 3.5 /x, width 1.2 to 4 /i. Hob., coast of Denmark.
2. MICROBACTEKIA, Cohn.
Rod-bacteria, cells cylindrical, short, having spon-
taneous movement.
A single genus, — Bacterium.
g. Bacterium, Duj. emend.
Cells cylindrical or elliptical, free or united
in pairs during their division, rarely in fours,
never in chains (leptothrix or torula), sometimes
in zooglcea (differing from the Z. of spherical B.
by a more abundant and firmer intercellular
substance), having spontaneous movements, os-
cillatory and very active, especially in media
rich in alimentary material and in presence of
oxygen.
CLASSIFICATION OF THE BACTERIA. 81
We might, as in the Spherobacteria, divide
the rod-bacteria into three groups: 1. the bac-
teria of putrefaction, B. termo, B. litieola, and
their varieties ; 2. the Bacteria of the lactic and
acetic fermentations, etc. ; 3. Chromogenes, B.
of colored milk and pus.
B. termo, Ehrb. 1830, Duj. (Vibrio lineola, Ehrb.
ex. p. 1838; Monas termo, Miiller).
Cells cylindrical, slightly swollen in the middle,
isolated, sometimes united in pairs, two to five times
as long as wide; length 2 to 3 yu, thickness 0.6 to
1.8 /JL : movements oscillatory.
Appears at the end of a very short time in
all infusions of animal and vegetable substances ;
multiplies with rapidity in numerous zooglcea ;
then disappears as other species, to which it
serves as nutriment, are developed. According
to recent observations, this bacterium has cilia
(Dallinger, Drysdale, Warming). Warming has
also found it in the state of torula.
B. termo is the veritable agent, the first cause,
of putrefaction, it is the true ferment saprogene
(Cohn).
M. "Warming has. recently described two allied forms : —
B. griseum, c"ells larger, more rounded ; length 2.5 to 4 /x,
thickness 1.8 to 2.5 ^. In infusions of fresh and salt water.
B. littoreum, cells elliptical or elongated, slightly rounded ;
length 2 to Q fj., thickness 1 .2 to 2.4 p. Coasts of Denmark.
B. lineola, Cohn ( Vibrio lineola, Ehrb. ex p.,
Duj., Miiller, V. tremulans, Ehrb., Bacterium
triloculare, Ehrb).
82 MORPHOLOGY OF THE BACTERIA.
Cells cylindrical, straight, rarely a little twisted,
larger than the cells of B. termo, isolated or united
in pairs, sometimes in fours, never more ; length
3.8 to 5.25 /z, thickness attains 1.25 //, ; movements
like those of B. termo, but a little more active.
Is found in various vegetable and animal in-
fusions of fresh or salt water, often takes the
form of zooglcea containing motionless rods in
their mucus substance. Warming has met it
in the form of chains composed of eight to ten
cells (torula). Its protoplasm is dotted with re-
fractive granules.
It is not known whether B. lineola constitutes
a specific ferment (Cohn).
The B. fusiform, Warming, differs from the preceding by
the form of its body, which is attenuated at the two extrem-
ities ; length 2 to 5 /z, width 0.5 to 0.8 p ; plasma not punc-
tated.
Beside these species, which have been well
studied, may be placed the following, which
demand new investigations : —
B. punctum, Ehrb.
Elongated rods, oval, colorless, having slow
movements, oscillating, often united in pairs;
length 5.2 /*, thickness 1.7 /*,. Diverse infusions
of animal substances.
B. catenula, Duj.
Body filiform, cylindrical, often united in
three, four, or five ; length 3 to 4 /*, thickness
0.4 to 0.5 p.. In fetid infusions, in typhoid fe-
ver (Coze and Feltz).
CLASSIFICATION OF THE BACTERIA. 83
Vibrio lactic, Pasteur.
" Articles almost globular, very short, a little
swollen at the extremities ; length of an article,
1.6 /i, of a series, 50 /*,."
This vibrio seems to resemble B. catenula or
B. termo. It is developed, according to Pas-
teur, in sweetened liquids, where it causes the
formation of Jactic acid and the coagulation of
the casein of milk. According to other re-
searches, coagulation of casein results from the
influence of a soluble ferment (zymase), and not
from an organized ferment.
Acetic ferment (Mycoderma aceti, Pasteur, Ulvina
aceti, Ktg.).
" Articles short, constricted, two to three times as
long as broad ; length 1.5 /*, often united in long
chains, forming pellicles on the surface of a liquid."
This species is also very similar to the pre-
ceding. It must not be confounded with the
Mycoderma vini, which may develop in the
same media, but which is a fungus of the group
of Saccharomycetes.
The acid fermentation of beer seems to be
due to a form of Bacterium resembling B. termo
(Cohn), but a little larger than the type. Cohn
has found it in beer undergoing acid fermenta-
tion, beside oval saccharomyces, elliptical bac-
teria, having movement, often united in pairs,
rarely in fours, etc.
Vibrio tartaric right (Pasteur).
Bacteria similar to those of the lactic fermentation,
PLATE IV.
From " Pasteur's Studies on Fermentation." MacmiUan fr Co., London, 1879.
" The engraving represents the different dfseased ferments, together
with some cells of alcoholic yeast, to show the relative size of these
organisms."
FIG. 1 represents the ferments of turned beer, as it is called. These
are filaments, simple or articulated into chains of different size, and having
a diameter of about the thousandth part of a millimetre (about Yroirir
inch). Under a very high power they are seen to be composed of many
series of shorter filaments, immovable in their articulations, which are
scarcely visible.
In No. 2 are given the lactic ferments of wort and beer. These are
small, fine, and contracted in their middle. They- are generally detached,
but sometimes occur in chains of two or three. Their diameter is a little
greater than that of No. 1.
In No. 3 are given the ferments of putrid wort or beer. These are
mobile filaments, whose movements are more or less rapid, according to
the temperature. Their diameter varies, but is for the most part greater
than that of the filaments of Nos. 1 and 2. They generally appear at the
commencement of fermentation, when it is slow, and are almost invari-
ably the results of very defective working.
In No. 4 are given the ferments of viscous wort, and those of ropy
beer, which the French call Jilante. They form chaplets of nearly spher-
ical grains. These ferments rarely occur in wort, still less frequently in
beer.
No. 5 represents the ferments of pungent, sour beer, which possesses an
acetic odor. These ferments occur in the shape of chaplets, and consist
of the mycoderma aceti, which bears a close resemblance to lactic ferments
(No. 2), especially in the early stages of development. Their physiolog-
ical functions are widely different, in spite of this similarity.
The ferments given in No. 7 characterize beer of a peculiar acidity,
which reminds one more or less of unripe, acid fruit, with an odor sui generis.
These ferments occur in the form of grains which resemble little spheri-
cal points, placed two together or forming squares. They are generally
found with the filaments of No. 1, and are more to be feared than the
latter, which cause no very great deterioration in the quality of beer,
when alone. When No. 7 is present, by itself or with No. 1, the beer ac-
quires a sour taste and smell that render it detestable. We have met
with this ferment existing in beer unaccompanied by other ferments, and
have been convinced of its fatal effects.
No. 6 represents one of the deposits belonging to wort. This must
not be confounded with the deposits of diseased ferments. The latter
are always visibly organized, whilst the former is shapeless, although it
would not always be easy to decide between the two characters, if sev-
eral samples of both descriptions were not present. This shapeless de-
posit interferes with wort during its cooling. It is generally absent
from beer, because it remains in the backs or on the coolers, or it may
get entangled in the yeast during fermentation, and disappear with
it. Among the shapeless granules of No. 6 may be discerned little
spheres of different sizes and perfect regularity. These are balls of
resinous and coloring matter that are frequently found in old beer at the
bottom of bottles and casks. They resemble organized products, but
are nothing of the kind.
PLATE IV
CLASSIFICATION OF THE BACTERIA. 85
with globular articles, short ; diameter 1 yu, united in
chains of 50 jj,.
Decomposes racemic acid, causing the right
tartaric acid to disappear, and setting free left
tartaric acid.
MlCROBACTERIA CHROMOGENES.
B. xanthinum, Schroeter ( Vibrio synxanihus, Ehrb.).
" Bodies cylindrical, slightly flexible, formed of cor-
puscles rarely exceeding five in number ; length of
an article, 0.7 to 1 p. In tainted cow's milk, to which
it gives a yellow color."
B. syncyanum, Schroeter ( Vibrio syncyanus, Ehrb.).
This Bacterium, which has the same charac-
ters as the preceding, has been observed in sour
milk, to which it gives a blue color.
B. ozruginosum, Schroeter.
In greenish blue pus.
These B. chromogenes resemble entirely the
lactic vibrios, B. termo or catenula. According
to Robin, colored milk contains colorless vibrios,
and the coloration is due to an alga similar to
Leptomitus.
B. brumieum, Schroeter.
Rods in a brown coloring matter in infusions
of rotten corn.
Following the colored Microbacteria, I place
two species of Bacterium recently described by
Ray-Lankester and Warming.
B. rubescens, Ray-Lank., 1873.
Under this name Ray-Lankester has described
86 MORPHOLOGY OF THE BACTERIA.
some phases of development of Clathrocystis roseo-
persicina of Cohn. Now Cohn is inclined to regard
the Monas vinosa, Ehrb. as the wandering cells of
Clathrocystis. On the other hand Warming has de-
scribed his : —
B. sulfuratum, Warming, 1876, giving it for synonymes,
Monas vinosa, Ehrb.; M. erubescens, Ehrb.; M. Warm-
ingiii Cohn; Rhabdomonas rosea, Cohn. It follows,
then, that the Monas which we have described with
the Spherobacteria should be referred to a Bacterium
called sulphuratum by Warming, but which is also
identical with B. rubescens of Ray-Lankester.
3. DESMOBACTERIA.
Filiform bacteria, composed of elongated cylin-
drical articles, isolated, or in chains more or less
extended, resulting from transverse division. Un-
der this form they correspond to leptothrix, Auct.
(differing from torula in that the filaments are not
constricted at the point of junction of the articu-
lations) ; filaments sometimes united in swarms,
never in zooglaa. Movements and state of re-
pose alternating and depending upon the presence
or absence of oxygen, the reaction of the medium,
and other conditions unknown. Some forms never
exhibit movement. — Bacteridie of Davaine (Cohn).
We will only preserve in the Desmobacteria the
genus Bacillus, Cohn. The vibrios are rather al-
lied to Spirillum because of their undulating fila-
ments.
However, after the exposition of the different
species of Bacillus, we will say something of three
genera of colorless oscillatoriacece, which are nearly
CLASSIFICATION OF THE BACTERIA. 87
related to them, — the Leptothrix, Beggiatoa, and
'Crenothrix.
1. Fil. with indistinct articulations :
Fil. very slender, short .... BACILLUS.
Fil. very slender, long .... LEPTOTHRIX.
Fil. thick, broad BEGGIATOA.
2. Fil. articulated distinctly .... CRENOTHRIX.
The following account of the bacilli has been
prepared by the author of the present volume
from the descriptions given by Magnin in the first
edition, in connection with those of more recent
authors, and from his own observations : —
g. Bacillus, Cohn.
The bacilli are short rods, which may be joined
in leptothrix chains, or may grow into long fila-
ments, apparently homogeneous, but in which,
by the use of staining reagents, the protoplasm
is seen to be divided into cubical or slightly
elongated masses. Some species have flagella
and are motile at a certain period of their
life-history ; others are always motionless. They
multiply both by binary division and by the for-
mation of highly refractive endogenous spores,
which are spherical or oval.
B. subtilis, Cohn ( Vibrio suUilis, Ehrb. ; Ferment
lutyrique, Pasteur).
This is the common " hay-bacillus," a widely
distributed species. The elementary rods are
88 MORPHOLOGY OF THE BACTERIA.
from 2 to 6 /x in length, and about 2 //, in
thickness. The single rods and short chains
exhibit active movements. Upon the surface of
a culture-medium they grow into long motion-
less leptothrix filaments, and rapidly develop
spores. These are oval, highly refractive bodies,
of 1 to 2 p in length, and from .6 to 1 //, in thick-
ness. (See Plate III.)
B. amylobacter, Van Tieghem (Amylobacter, Uro-
cephalwn and Clostridium Trecul).
B. occurring, like the preceding, under various
forms, — in pointed cylindrical filaments of 6.6 to
26 jj, in length and 1.1 /A in thickness, or in form of
tadpole, with a spore in the terminal swelling, or of a
spindle, with a spore in the middle. In fact, it does
not differ from B. subtilis, except by the appearance
of starch in its protoplasm at the end of the period
of multiplication. These B. are sometimes endowed
with movement (Ny lander).
It develops in vegetable tissues, which fall
into putrefaction, spontaneously, according to
Trecul, or introduced from without by a mech-
anism still unknown. This is the essential agent
of vegetable putrefaction (Van Tieghem).
B. ulna, Cohn ( Vibrio bacillus, Ehrb.).
Filaments articulated, thick, and rigid, formed of
one, two to four articles, straight or broken in zigzag;
length of an article 10 /i, length of a filament of four
articles 42 ^ ; slow movements of rotation and of
progression.
CLASSIFICATION OF THE BACTERIA. 89
B. rnber, Cohn.
Long rods, isolated or united in two or four,
movement very active ; in a red mucous sub-
stance, vermilion, developed upon grains of rice.
Observed by Franck and Cohn. •
B. anthracis, Cohn.
Found in the blood, and especially in the
capillary blood-vessels, of animals affected with
anthrax. From 5 to 20 /x in length, and about
1 p, in thickness, straight or slightly curved,
truncated, motionless ; growing in culture-solu-
tions into long filaments, which are often twisted
into bundles. These filaments appear to be
homogeneous, but by the use of staining re-
agents the protoplasm is seen to be divided into
cubical masses contained in a hyaline sheath.
Oval spores are developed at intervals in these
filaments when they have free access to oxygen.
(See Plate VIII.)
B. tuberculosis, Koch.
Found in the sputum of phthisical patients,
in tubercle nodules wherever found, in caseating
scrofulous glands, in bovine tuberculosis, etc.
Extremely slender, somewhat flexible rods,
having a length of one-quarter to one-half the
diameter of a red blood-corpuscle (Koch), mo-
tionless, and scarcely discernible except when
stained ; often containing very minute spores.
(See Plate IX.)
90 MORPHOLOGY OF THE BACTERIA.
B. leprae, Hansen.
Found in the large cells of leprous nodules
of the skin and of internal organs. Extremely
slender rods, which in form and staining quali-
ties are said greatly to resemble the bacilli of
tuberculosis ; from 4 to 6 p. in length and having
pointed extremities. Shining oval spores have
been observed in the rods, and they are said
sometimes to be motile. (See Fig. 16, p. 332.)
B. of symptomatic anthrax (Charbon symptomat-
ique ; blackleg, quarter-evil).
Mobile rods, having rounded extremities,
somewhat shorter and broader than B. anthracis.
The rods sometimes form short chains, and fre-
quently contain an oval spore at one extremity.
(See Fig. 1, Plate VII.)
B. of malignant oedema, Koch ; vibrion septique,
Pasteur.
Rods with rounded ends, 3 to 5/t in length
and I/A in thickness, solitary or in leptothrix
chains; forming spores without free access of
oxygen — anaerobic. (See Fig. 2, Plate VII.)
B. of glanders, Shiitz and Loffler.
Extremely minute bacilli found in the nodules
of the nasal mucous membrane, and of internal
organs of horses dead from glanders.
CLASSIFICATION OF THE BACTERIA. 91
B. of septicaemia of mice, Koch.
Extremely minute bacilli .8 to 1 p, long, and
.1 to .2fM thick, solitary or in short chains; found
chiefly in the white blood-corpuscles of septicse-
mic mice. (See Fig. 19, p. 353.)
B. of cholera, Koch.
Found in the rice-water discharges of cholera
patients, and within the mucous membrane and
tubular glands of those dead of this disease.
The bacilli are described as comma-shaped, mo-
bile organisms, which occur in wavy masses, and
form characteristic colonies in gelatine cultures.
g. Leptothrix, Ktz.
The Leptothrix differ from Bacilli by their fila-
ments being very long, adherent, very slender, and
indistinctly articulated. Numerous species have been
described.
g. Beggiatoa, Trev.
Filaments very slender, surrounded by mucous
matter, rigid, having oscillatory movements. Proto-
plasm white, enclosing numerous granules, which
recent observations have demonstrated to be crystal-
line sulphur (Cramer, Cohn).
4. SPIROBACTERIA.
This tribe includes the bacteria with undulating
filaments, or filaments in spirals, more or less de-
92 MORPHOLOGY OF THE BACTERIA.
veloped, from the Vibrio rugula, which only pre-
sents a single curve in its centre, to certain species
of Spirillum which have numerous turns of the
spiral. In several species, cilia, or a flagellum, have
recently been observed.
We divide them into three genera : —
Fil. short, slightly sinuous . . . VIBRIO.
Fil. short, spiral, rigid .... SPIRILLUM.
Fil. long, spiral, flexible .... SPIROCHJETE.
g. Vibrio, Auct. emend.
Body filiform, more or less distinctly articu-
lated, always undulating, having serpentine
movements. This genus forms the transition
between the Desmobacteria and Spirillum"hom
which it cannot be separated " (Warming).
Fil. thick, with a single curve ... V. RUGULA.
Fil. slender, with several undulations . V. SERPENS.
V. rugula, Miiller (V. lineola, Duj. ex parte).
Filament presenting in its centre a single curva-
ture, feeble but distinct ; length 8 to 16 JJL. The
shortest are slightly curved (=6/1- Warming), the
larger, which may attain 17.6 /JL (Cohn), 85 p (Warm.),
are about to divide. Movements of rotation more or
less rapid around their longer axis ; of progression
forward, giving then the idea of a serpentine move-
ment: having a cilium (Warming).
V. rugula is commonly found in swarms, in
infusions, in deposits upon the teeth, in intes-
tinal matters (Leeuwenhoeck), in choleraic dis-
charges (Pouchet).
CLASSIFICATION OF THE BACTERIA. 93
V. serpens, Miiller.
Filament one half less in diameter than the pre-
ceding, rigid, annulate, having two or three regular
undulations, at least two m the shortest ; height of
one turn of the undulations 8 to 12 yu,, diameter 1 to
3 /z, total length 11 to 25 /-t, thickness 0.7 //, ; move-
ments analogous to those of B. subtilis ; having a cil-
ium (Warm.).
In numerous swarms in inf usions, river water,
etc.
g. SpirochsBte, Ehrb.
S. plicatilis, Ehrb.
Filament not extensible, twisted in a long helix,
flexible, the turns of the spiral near together ; suscep-
tible of twisting upon its axis and of an undulatory
movement ; total length 130 to 200 /z.
Rare species; in infusions, stagnant water,
sea- water, etc.
S. Obermeieri, Cohn.
Does not differ from the preceding, either in size,
conformation, or in its movements, but by its habitat
and physiological peculiarities.
In the blood of persons attacked by recurrent
fever (Obermeier, 1872, Weigert, Birch-Hirsch-
feld, etc.) during the period of access, never
during the remission.
S. gigantea, Wanning. Found upon the coasts of Den-
mark ; thickness of body, 3 p, height of spiral 25 /i, diam-
eter 7 to 9 /*.
94 MORPHOLOGY OF THE BACTERIA.
g. Spirillum, Ehrb.
Filament spiral, rigid; turns of spiral short
and regular.
S. tenue, Ehrb.
Filament slightly tortuous, three to four turns of
the spiral ; length and diameter of a single turn, 2 to
3 fi. When the filament has a turn and a half, it re-
sembles an n, ; the filaments of two to five turns have
a length of 4 to 15 /z, ; spiral movement very rapid.
In infusions, etc.
S. undula, Ehrb. (Vibrio prolifer, Ehrb.)
Filament larger, turns of the spiral wider apart
(from 3 to 5 /A) ; having usually one half a turn to
one full turn, rarely one and a half, two, or three ;
length 8 to 10 /*, breadth 5 /i, thickness of filament
1.3 jj, ; having a very rapid spiral movement.
Fetid animal and vegetable infusions and run-
ning water.
The S. rufum, Pertz, only differs from this by its reddish
color.
S. volutans, Ehrb.
Filament large and thick, turns of spiral regular,
well separated, and 13 /z in height ; number of turns
two, three, and three and a half, rarely six arjd seven ;
total length 25 to 30 /*, thickness 1.5 /x, breadth 6.6 //,;
movement sometimes rapid, sometimes motionless ;
a well-defined cilium, already seen by Ehrenberg
(Cohn, Warming).
This giant of the bacteria is found in vege-
table and animal infusions, in sea-water, and in
fresh water.
u.:* ••. 2.*. '/ •:•
PLATE V
W"
. • • . • '
Pi
£%£
•9
*..•:: *%:•/
lUi -•-•'' i-:''5-
* C'i ^V^
»t *• "- • • ••
PLATE V.
From " Microscopical Journal."
FIG. 1. — Micrococcus prodigiosus (Monas prodigiosa, Ehr.). Spherical
bacteria of the red pigment, aggregated in pairs and in fours ; the other
pigment bacteria are not distinguishable with the microscope from this
one.
FIG. 2. — Micrococcus vaccines. Spherical bacteria, from pock-lymph in
a state of growth, aggregated in short four to eight-jointed straight or
bent chains, and forming also irregular cell-masses.
FIG. 3. — Zoogloea-form of micrococcus, pellicles or mucous strata
characterized by granule-like closely set spherules.
FIG. 4. — Rosary chain (Torula-form) of Micrococcus urece, from the
urine.
FIG. 5. — Rosary-chain and yeast-like cell-masses from the white de-
posit of a solution of sugar of milk which had become sour.
FIG. 6. — Saccharomyces glutinis (Cryptococcus glutinis, Fersen.), a pullu-
lating yeast which forms beautiful rose-colored patches on cooked
potatoes.
FIG. 7. — Sarcina spec,* from the blood of a healthy man,** from the
surface of a hen's egg grown over with Micrococcus luteus, forming yel
low patches.
FIG. 8. — Bacterium termo, free motile form.
FIG. 9. — Zoogloea-form of Bacterium termo.
FIG. 10. — Bacterium-pellicle, formed by rod-shaped bacteria arranged
one against the other in a linear fashion, from the surface of sour beer.
FIG. 11. — Bacterium lineola, free motile form.
FIG. 12. — Zooglcea-form of B. lineola.
FIG. 13. — Motile filamentous Bacteria, with a spherical, or elliptical
highly refringent " head/' perhaps developed from gonidia.
FIG. 14. — Bacillus subtilis, short cylinders and longer, very flexible
motile filaments, some of which are in process of division.
FIG. 15. — Bacillus ulna, single segments and longer threads, some
breaking up into segments.
FIG. 16. — Vibrio rugula, single or in process of division.
FIG. 17. — Vibrio serpens, longer or shorter threads, some dividing into
bits, at * two threads entwined.
FIG. 18. — " Swarm " of V. serpens, th« threads felted.
FIG. 19. — Spirillum tenue, single and felted into " swarms."
FIG. 20. — Spirillum undula.
FIG. 21. — Spirillum vofutans* two spirals twisted around one another.
FIG. 22. — Spirochcete plicatilis.
All the figures were drawn by Dr. Ferdinand Cohn with the immersion
lens No. IX. of Hartnack Ocular III., representing a magnifying power
of 650 diameters.
96 MORPHOLOGY OF THE BACTERIA.
M. Warming has recently described three new species
found upon the coast of Denmark : —
Sp. violaceum, height 8 to 10 /*, diameter 1 to 1.5 /*, thick-
ness 3 to 4 p ; a cilium at each extremity.
Sp. Rosenbergii, height of helix 6 to 7.5 /i, thickness 1.5 to
2.6 p.
Sp. attenuatum, body very attenuated at the two extrem-
ities, without a cilium.
We give below some details concerning the
other colorless Schizophy tes : —
g. Sarcina, Goods.
The Sarcina, which it is useless to describe
here, can be considered as bacteria in which
the division occurs by two perpendicular par-
titions in such a manner that multiplication
takes place in two directions.
Sarcina is very nearly allied to Merismopedia,
from which it only differs by the absence of
chlorophyll ; its siliceous skeleton allies it with
the diatoms.
g. Ascococcus, Billr.
Cells hyaline, small, globular, closely united in
globular or oval families, irregularly lobed and lobu-
lated, surrounded by a thick gelatinous envelope,
cartilaginous, forming a soft membrane, flaky, easily
separating.
A. Billrothi, Cohn.
Families in masses of 20 to 160 /i, surrounded by a thick
membrane of 15 /*.
In a solution of tartaric acid exposed to the air.
g. Myconostoc, Cohn.
Filaments very slender, colorless, folded, rolled up
in a mucous substance, united in very small globules.
CLASSIFICATION OF THE BACTERIA. 97
M. gregarium^ Cohn.
Unique species found on the surface of a putrefying
infusion.
g. Cladothrix, Cohn.
Filaments in form of leptothrix, very slender, color-
less, not articulated, rigid or a little undulating, falsely
dichotomous.
Cl. dichotomy Cohn. In foul water,
g. Streptothriz, Cohn.
Filaments in form of leptothrix, very slender, color-
less, not articulated, straight or slightly spiral, a little
branched.
Str. Fcersteri, Cohn.
In concretions in the lachrymal canal of man.
PART SECOND.
PHYSIOLOGY OF THE BACTEEIA.
PAET SECOND.
PHYSIOLOGY OF THE BACTERIA.
CHAPTER I.
DEVELOPMENT OF THE BACTERIA.
THE bacteria are now known to us from a mor-
phological point of view : let us proceed to study
the life of these microscopic beings ; first, from
a general point of view, that is to say, by study-
ing their functions of nutrition and reproduction,
independently of the special characters impressed
upon these functions by certain media; then by
considering the relations which are established
between the bacteria and the particular media in
which they may be developed.
The bacteria are of all beings the most widely
diffused. We meet them everywhere, — in the
air, in water, upon the surface of solid bodies, in
the interior of plants and animals. If we expose
a transparent liquid containing traces of organic
substances, we find after a short time that it has
become clouded, and the microscope shows us that
it contains myriads of these beings.
What is the source of these organisms so widely
disseminated, and which develop so rapidly? This
DEVELOPMENT OF THE BACTERIA. 101
is the first question which presents itself, — a ques-
tion which has given rise to long discussions, in
the examination of which we shall only enter in
order to give a short historical statement.
§ 1. — ORIGIN OF THE BACTERIA.
The origin of the bacteria, as of all the other
inferior organisms, is conceived in three different
manners : —
1. For some, these organisms are produced by
heterogenesis ; that is to say, by creation outright
from mineral or organic substances (spontaneous
generation).
2. According to others, they come directly from
individuals like themselves, by one of the known
modes of generation, — fission, spores, etc.
3. Finally it is believed that they are derived
from organisms already existing, and are nothing
more than different states or phases of develop-
ment of known species, of which the life cycle is
not 'yet discovered.
We will examine the latter hypothesis, which
constitutes what is called polymorphism, when we
speak of the phenomena of reproduction.
As to the two first, we will content ourselves
with indicating the late works which have appeared
for and against each; insisting above all upon the
facts which relate to the proof of the presence of
bacteria or their germs in the air, water, and
liquids or tissues of the. human organism, — blood,
urine, etc.
102 PHYSIOLOGY OF THE BACTERIA.
Heter agenesis. — Since the experiments of Pou-
chet and of his pupils, and the arguments given
by MM. Trecul and Fremy, the last facts invoked
in favor of heterogenesis are due to MM. Onimus,
Servel, Bastian, etc.
M. Onimus contends that the " proto-organisms
may be born in media, protected against the air,
which contain albuminoid substances."
M. Martin sustains an analogous idea. Accord-
ing to him, the bacteria are derived from protein
granules. According to Neusch, bacteria are pro-
duced in the interior of animal or vegetable cells
without any lesion and without coming from the
air. To demonstrate this he plunges divers fruits
under water, in saline or acid liquids (phosphates,
sulphates, carbonate of potassa, etc.), and he finds
there bacteria ; but, according to him, these are
not living organisms, properly so called, but ab-
normal cellular vegetations.
M. Servel, decapitating some guinea-pigs, caused
the heads, the livers, and the kidneys to fall into
a solution of chromic acid, 1 to 100. At the end
of several days, the superficial parts were hard-
ened ; but the centre was softened, and filled with
bacteria.
The presence of bacteria in eggs has several
times been verified, and the heterogenists have
hastened to draw an argument from this fact in
favor of their theory. M. Gay on explains the ap-
pearance of these organisms in the eggs of birds
by their presence in the normal state in the
oviducts.
DEVELOPMENT OF THE BACTERIA. 103
Finally, Bastian, having succeeded in obtaining
bacteria in liquids which he believes deprived of
every germ, believes in their spontaneous genera-
tion. The following is a resume of his experiment :
Normal acid urine is brought to the boiling-
point, then a solution of potash (in sufficient quan-
tity to neutralize the volume of urine employed)
is also brought to the boiling-point ; after cooling,
the two liquids are mixed, and the whole placed
in an oven at 50°. At the end of two or three
days, bacteria are developed.
Pasteur points out three causes of error in the
experiment of Bastian : 1. The germs may come
from the urine ; 2. The germs may come from the
solution of potash; 3. The germs may be fur-
nished by the vessels employed in the experiment.
In support of this criticism, Pasteur has made some
similar experiments, guarding against these causes
of error, and has not obtained bacteria.
DISSEMINATION OF BACTERIA IN AIR AND WATER.
Air. — The experiment of Pasteur for gathering
atmospheric germs is well known. He fixes a
glass tube in an aperture made in a window-blind.
The extremity of the tube, which communicates
with the open air, is closed with a plug of cotton,
to the other extremity is attached an aspirator.
When the air has filtered through the cotton for
some hours, this is examined, and is found to be
filled with germs.
104 PHYSIOLOGY OF THE BACTERIA.
Before Pasteur, Ehrenberg and G. de Claubry
had already announced the presence in the air of
the eggs of infusoria. Robin had also recognized
that the atmosphere contains, in addition to all
sorts of debris, spores, pollen-grains, portions of
insects, and rarely the eggs of infusoria. More
recently Maddox and Cunningham, by the aid of
an aeroscope invented by the former, gathered
numerous microbes, as well as bacteroid particles.
Tyndall, by causing a ray of light to enter a dark-
ened chamber, has rendered visible all these mi-
nute corpuscles. His researches show that the
optical examination of air enables us to determine
in an exact manner the presence or absence of
germs.
Let us also mention the experiments recently
made by Miquel in the park of Montsouris. This
observer has found in the atmosphere a consider-
able number of germs. For the forms of which
the diameter exceeds 2 p, he has ascertained that
" the average number of microbes in the air is
feeble in winter and augments rapidly in spring,
etc. ; 2. That rain always diminishes the number
of these microbes; 3. That rain-water introduced
with the greatest precautions, into flasks with slen-
der curved necks, first heated to destroy germs,
rarely contains rotifers, etc., but always contains
bacteria."
En resumt, the existence of germs can be dem-
onstrated, 1, by direct research ; and 2, by cultiva-
tion. Direct research may be made by the optical
examination of the air (method of Tyndall), the
DEVELOPMENT OF THE BACTERIA. 105
microscopic examination of dust (method followed
by Marie-Davy, Tissandier), the examination of
particles obtained by filtration, by gathering germs
•with an aeroscope, by condensation of atmospheric
moisture upon refrigerating vases., etc. The culti-
vations consist in exposing to the air which is to
be examined some liquids in which all pre-existing
germs have been destroyed (Pasteur, Tyndall,
etc.). This method has shown that liquids exposed
in an atmosphere deprived of all germs does not
undergo putrefaction, but this occurs as soon as
the access of air not deprived of germs is per-
mitted (Tyndall).
All of these methods give concordant results;
deposits containing germs of various kinds are
always obtained. But this objection presents itself
to the mind : Do the bacteria obtained by cultiva-
tion exist in the atmosphere ? or do they come
from germs which have developed rapidly upon
finding a favorable medium ? From the experi-
ments of Cohn, Miquel, etc., it is known that the
atmosphere contains very few adult bacteria. Mi-
quel in a recent communication says, in effect, that
bacteria are rarely found in the air in a complete
state, but rather under the form of shining points,
difficult to distinguish directly one species from
another. Are not these brilliant points Micrococcif
In other terms, the air contains permanent spores,
organisms which, as we shall see in speaking of the
reproduction of the bacteria, develop at a certain
period of the existence of the adult forms, in their
interior, which escape from the sporogenous fila-
106 PHYSIOLOGY OF THE BACTERIA.
ment, are drawn into the air by the evaporation of
the liquid containing them, or, after dessication, by
the winds. These spores are the point of depart-
ure of epidemic foci, and their extreme lightness
explains how readily they are disseminated by the
winds.
Water. — Water contains considerable quantities
of bacteria and especially of germs. Their pres-
ence in atmospheric water is established by the
experiments of Lemaire and Gratiolet, — and after
them by more recent observers, — by means of con-
densers filled with ice, and placed in the fields and
for comparison in closed apartments. Rindfleisch
has since expressed the opinion that the vapor of
water does not contain spores or bacteria, and that
telluric waters alone contain them ; but Billroth,
Cohn, and others have proved that Kindfleisch was
too positive in his statement.
It is not surprising that telluric waters contain
such a quantity of bacteria that their existence is
admitted by all. The dust gathered upon the sur-
face of stones, of leaves, of fruits, etc., shows upon
microscopic examination an abundance of germs
(Mari£-Davy, Tissander) ; the washing of these
objects and of the soil by the rain transports them
into the rivers and from the rivers to the sea,
which contains considerable quantities of them.
Thus, a drop of water from the Seine, according
to Pasteur and Joubert, is always fecund, and may
give birth to several species of bacteria. The dis-
tilled water of laboratories also contains germs, and
DEVELOPMENT OF THE BACTERIA. 107
these of so small a diameter that they pass through
all filters.1 Cohn has proved that some are not
arrested by a super position of sixteen filters. The
only waters which do not contain them are those
drawn from the very source of a spring.
DISSEMINATION OF BACTERIA IN THE HUMAN
ORGANISM.
If bacteria are so generally disseminated in the
great external media, it is not surprising that they
are found on the surface of the human body and
in the interior of the organs in communication
with the exterior. But to account for their pres-
ence in the interior of organs we find ourselves in
presence of two hypotheses: one admitting the
spontaneous production of these organisms in the
interior of the tissues, the second explaining it
by the introduction through the membranes of the
germs of bacteria from without.
1 Having been directed by the National Board of Health to make
some experiments with a view to confirming or disproving the results of
Klebs and Crudelli, who claim to have found the germ of malarial fevers
in the atmosphere of the Pontine marshes near Rome (their Bacillus ma-
laria), I aspirated ten gallons of air on the edge of a swamp in the vicin-
ity of New Orleans, through 4 c.c. of distilled water. Upon examining
this water with the microscope on the following morning, I was surprised
to find a large number of actively moving bacteria and monads (Monas
lens). To make sure that these really came from the air, I examined my
distilled water, which had been standing in the laboratory for several
weeks (in a bottle, corked, but occasionally opened as distilled water was
required) and found the s-ame forms present in considerable numbers,
not so numerous, however, as in the water through which swamp air had
been drawn. As the germs were present in the distilled water, I presume
that the passing of air through it for several hours, and the organic
matter contained in it, favored the development and multiplication of
these micro-organisms. Subsequent experiments with freshly distilled
water gave very different results as to the number of organisms found
— G. M. S.
108 PHYSIOLOGY OF THE BACTERIA.
In truth, the cutaneous surfaces are penetrated
with difficulty by germs, although the hairs upon
the surface of the body serve to collect them.
The short hairs in the nares prevent, to some ex-
tent, the atmospheric germs from penetrating into
the bronchi, but this protection is not sufficient ;
and, notwithstanding the mucus of the nasal fossse
and of the pharynx, they may be found in the al-
veoli of the lungs, if we may believe Rindfleisch
and Eberth. Do the bacteria pass into the blood ?
They may be transported in food and drink into
the alimentary canal, where an elevated tempera-
ture, the presence of saliva, etc., favor their de-
velopment. On the other hand, the acid secretions
of the stomach, the bile, and the pancreatic juice
moderate, if they do not prevent, the multiplica-
tion of these organisms.
The presence of bacteria in normal blood and
urine, or their occasional entrance into these fluids,
are important questions, which have induced many
contradictory researches, but which are not yet
definitely settled.1
1 " If there is any organism in the blood of yellow fever demon-
strable by the highest powers of the microscope as at present perfected,
the photo-micrographs taken in Havana should show it. No such organ-
ism is shown in any preparation photographed immediately after collection. But
in certain specimens kept under observation in culture cells, hyphomy-
cetous fungi and spherical bacteria made their appearance after an inter-
val of from one to seven days. The appearance of these organisms was,
however, exceptional ; and in several specimens taken from the same
individual at the same time, it occurred that in one or two a certain fun-
gus made its appearance, and in others it did not. This fact shows that
the method employed cannot be depended upon for the exclusion of atmos-
pheric germs, but does not affect the value of the result in the consider-
able number of instances in which no development of organisms occurred
DEVELOPMENT OF THE BACTERIA. 109
Two kinds of researches have been undertaken
for the purpose of discovering germs in normal
blood. The direct method, or microscopic exam-
inatfon, has given results very much disputed.
The blood contains, indeed, a considerable number
of little granules, of which the nature is doubtful,
and which it is difficult to distinguish from Micro-
coccus. Thus, while Lu'ders asserts that normal
blood contains germs, or spores, which only await
a favorable alteration in the fluid in order to de-
velop themselves, Rindfleisch formally denies their
existence.
The indirect method, which consists in cultivat-
in culture cells in which blood, in a moist state was kept under daily
observation for a week or more.
" The method employed seemed the only one practicable for obtaining
blood from a large number of individuals without inflicting unwarrant-
able pain and disturbance upon the sick. It was as follows : One of the
patient's fingers was carefully washed with a wet towel (wet sometimes
with alcohol and at others with water), ancl a puncture was made just
back of the matrix of the nail with a small triangular-pointed trocar
from hypodermic syringe case. As quickly as possible a number of thin
glass covers were applied to the drop of blood which flowed. And these
were then inverted over shallow cells in clean glass slips, being attached
usually by a circle of white zinc cement. In dry preparations, which
are most suitable for photography, the small drop of blood was spread
upon the thin glass cover by means of the end of a glass slip.
u The thin glass covers were taken from a bottle of alcohol, and
cleaned immediately before using; and usually the glass slips were
heated shortly before applying the covers, for the purpose of destroying
any atmospheric germs which might have lodged upon them. These
precautions were not, however, sufficient to prevent the inoculation of
certain specimens by germs floating in the atmosphere (Penicillium and
micrococci) ; and in nearly every specimen the presence of epithelial cells,
and occasionally a fibre of cotton or linen, gave evidence that under the
circumstances such contamination was unavoidable. It is therefore be-
lieved that any organism developing in the blood of yellow-fever, or
of other diseases collected by the method described, or by any similar
method, can have no great significance, unless it is found to develop as
a rule (not occasionally) in the blood of patients suffering from the dia-
110 PHYSIOLOGY OF THE BACTERIA.
ing normal blood in flasks perfectly closed, has also
given some favorable results, such as those of
Hensen, Tiegel, Billroth, and Nedvedsky, and
some unfavorable results, as those of Lliders»and
Pasteur. According to Nedvedsky, the blood " con-
tains germs capable of undergoing in it, under
certain circumstances, an ulterior development :
these are the ffemococcos." If these germs do not
give birth, normally, to bacteria, it is because the
blood is as injurious to them as the most advanced
stages of putrefaction (Billroth). If this hypoth-
esis is true, it explains several embarrassing facts,
such as the existence of micrococci in the pus of
ease in question, and is proved by comparative tests not to develop in
the blood of healthy individuals, obtained at the same time and by the
same method.
" Tried by this test, it must be admitted that certain fungi and groups
of micrococci, shown in photographs taken from specimens of yellow-
fever blood collected at the military hospital and preserved in culture
cells, cannot reasonably be lupposed to be peculiar to or to have any
causal relation to this disease." — Preliminary Report of Havana Commis-
sion to National Board of Health.
In subsequent observations upon the blood of malarial fever, of
syphilis, and of leprosy, I have sometimes obtained a development of
micrococci in culture cells where all possible precautions as to the exclu-
sion of atmospheric germs had been taken, and in one case have seen
the development of PeniciUium in another of Sarcina. The last observa-
tion is, so far as I know unique, and I have still in my possession the
culture-slide containing numerous masses of Sarcina, presenting the
characteristic arrangement of the cells in fours. This slide was put up
at the bedside of a patient suffering from intermittent fever in the Char-
ity Hospital, New Orleans. Evtry precaution was taken to exclude at-
mospheric germs. The patient's finger was washed with absolute alcohol
just before making the puncture from which the little drop of blood \\as
obtained. The question as to whether in this and similar cases the
germs of the organism which develops come from the atmosphere or
pre-existed in the blood is one to which I propose to give special atten-
tion ; and, after further experiment, I shall discuss it in my report to the
National Board of Health. — G. M. S.
DEVELOPMENT OF THE BACTERIA. Ill
closed abcesses, in cysts, in urine drawn from the
bladder, etc.
§ 2. — NUTRITION AND RESPIRATION OF THE
BACTERIA.
The bacteria, being organisms composed of a
cell membrane of cellulose, and of protoplasmic
contents, deprived of chlorophyll, must receive
nutriment and respire in the same manner as all
the colorless vegetables and all the inferior animals
deprived of special apparatus, — that is to say, by
end osmotic absorption.
Although the media in which the bacteria de-
velop are various, yet, from the point of view of
the nutritive function, they act everywhere^ ac-
cording to the same laws. No matter in what
medium they live, they must have water, nitro-
gen, carbon, and oxygen, as well as certain min-
eral salts which enter, but in quantities exceedingly
minute, into the chemical constitution of all organ-
ized bodies.
Water. — This element is indispensable to the
active life and development of the bacteria. Dessi-
cation arrests completely the movements of those
which are mobile, and the functions of all the
bacteria in general ; but it does not kill them,
at least if it be not prolonged beyond a certain
time. The micrococci of different kinds of virus
are examples of the continued vitality of these
organisms after dessication for a considerable time.
112 PHYSIOLOGY OF THE BACTERIA.
The bacteria present in this respect numerous va-
riations according to the species and the period of
development which they have attained. In the
state of permanent spores, they are extremely ten-
acious of vitality. They resist for a long time
not only dessication, but a considerable elevation
of temperature.
Among the bacteria, some are developed in liq-
uids, — the greater number, — others upon damp
surfaces. The former can live in fresh water, sea-
water, thermal waters, and the liquids of animal
or vegetable organisms, etc. A surprising fact
is, that the composition, so different, of fresh and
sea water appears to have no influence upon the
bacteria. We find in both all the species, from
Bacterium termo to Spirillum volutans.
Nitrogen. — Pasteur has demonstrated that it is
not necessary that the nitrogen which is to serve as
nutriment to the bacteria should be in the form of
albumen, but that these organisms can take posses-
sion of it in the form of ammonia.
In fact, in Pasteur's solution, composed as fol-
lows : —
Distilled water 100.
Sugar candy 10.
Tartrate of ammonia .... 1.
Ashes of one gramme of yeast . 0.075.
the bacteria increase sometimes with such rapidity
that they interfere with the development of the
alcoholic ferment.
DEVELOPMENT OF THE BACTERIA. 113
Cohn. in order to better observe the phenomena
and to get rid of the moulds, which the cane-sugar
caused to develop too rapidly, employed the fol-
lowing culture-fluid : —
Distilled water .... 100.
Tartrate of ammonia . . 1.
Ashes of yeast .... 1.
Bacteria develop in this fluid wonderfully, which
proves that sugar is not indispensable to them.
One other solution often employed is that of
Mayer. It has the advantage of not requiring the
employment of ashes of yeast : —
Phosphate of potash ... 0.1 gramme.
Sulphate of magnesia ... 0.1 „
Tribasic phosphate of lime . 0.1 „
Distilled water 20 c.c.
Cohn adds to this 0.2 gr. tartrate of ammonia.
En resume, the bacteria can take nitrogen, which
they need in order to form their protoplasm, either
from albuminous compounds, which they decom-
pose, as in putrefaction, or in the form of am-
monia, or, perhaps, by borrowing it from nitric
acid, but this last source is not well established
(Conn),
Carbon. — In addition to the sources common
to other organisms, the bacteria can take this im-
portant element of their composition, under cer-
tain circumstances, from the organic acids. Thus,
when we cultivate bacteria in a solution containing
8
114 PHYSIOLOGY OF THE BACTERIA.
only tartrate of ammonia with a small quantity of
mineral salts (phosphoric acid, potash, sulphuric
acid, lime, and magnesia), they develop rapidly,
taking their carbon from the tartaric acid.
Cohn has endeavored to ascertain if other or-
ganic acids could be assimilated by the bacteria.
By making use of succinate of ammonia, or neutral
acetate of ammonia, he has been able to cultivate
these microphytes. Besides, as Pasteur had already
experimented with solutions containing laotates, and
in which bacteria had developed until the salt had
completely disappeared, we may admit that the
bacteria can assimilate the organic acids, — tartaric,
succinic, acetic, and lactic ; but tartaric acid seems
to furnish the best alimentary solution.
Other substances containing carbon are also as-
similated by the bacteria, — cane-sugar, milk-sugar,
glycerine, and even cellulose (according to Mit-
scherlich).
Cohn concludes, " that the bacteria multiply quite
normally, and in great quantity, whenever they
find the elements in solution which constitute
ashes, and that they can take the carbon which
they need from any organic substance containing
it, and their nitrogen from ammonia, urea, and
probably from nitric acid. The bacteria, then, re-
semble green plants, in that they assimilate nitro-
gen contained in their cells by taking it from
ammonia compounds, which animals cannot do.
They differ from green plants in that they cannot
draw their carbon from carbonic acid, and only
assimilate organic substances containing carbon,
DEVELOPMENT OF THE BACTERIA. 115
above all the hydrates of carbon and their deriv-
atives ; and in this respect they resemble animals."
Absorption. — How are these various substances
absorbed ? The observations of Grimm, Hoffmann,
de Seynes, etc., permit us to assure ourselves that
these organisms absorb by endosmosis the sub-
stances upon which they are nourished.
Grimm, upon examining with the microscope
some particles of lemon containing bacteria and
spores of algae, saw a certain number of the former
gather around a spore, and fix themselves to it
by one of their extremities. They did not pene-
trate it; but when they abandoned it, the spore
had diminished in volume, and lost a portion of its
contents, while the bacteria had taken a greenish
color.
Hoffmann has seen that these little organisms,
when placed in a solution of carmine or of fu-
schine, after a time are colored an intense red,
while the mucus surrounding them remains color-
less.
De Seynes, also, from his observations upon
the vibrios which accompanied some colored fila-
ments of Penicillium glaucitm, believes that bacte-
ria are susceptible of absorbing coloring matters
from vegetables and from animals with which they
are in contact.
Oxygen. — The role of oxygen in the life of the
bacteria has given rise to numerous controversies.
First, it seems a priori that the bacteria ought
116 PHYSIOLOGY OF THE BACTERIA.
to act like all other living beings, and to respire
like the other inferior organisms deprived of chlo-
rophyll — that is to say by absorbing oxygen and
eliminating carbonic acid. This is, indeed, the
opinion of a great number of botanists. But,
according to Pasteur, it is not so with the bacteria.
When we examine what occurs in putrefaction,
we find that at first certain species are developed
(Monas crepusculum, Bacterium termo, etc.), which
absorb all the oxygen dissolved in the liquid, and
come to the surface where they form a thick veil ;
after this, other species of vibrioniens appear,
which are developed in a medium entirely de-
prived of free oxygen, by borrowing this gas
from the fermentable matters contained in the
liquid. These chemical decompositions constitute
putrefaction.
The first of these organisms, regarding the na-
ture of which Pasteur has long been uncertain,
are aerobies : they live in contact with the air, and
have need of oxygen. The second, anaerobies,
not only have no need of oxygen, but are killed
by it.
These differences in the respiration of organ-
isms belonging to the same group are not admitted
by a great number of recent observers. Hoff-
mann, among others, says expressly : " These little
beings cannot live without air, I should say with-
out oxygen : if this gas is wanting, they cease to
move and do not multiply at all. If a drop of
liquid full of bacteria is placed upon a glass slip,
then covered by a piece of thin glass, the active
DEVELOPMENT OF THE BACTERIA. 117
bacteria will all approach gradually to the margins
of the cover; and it is there that at the end of
several days, after the successive death of the
greater number, some are still found endowed with
life and movement. If a similar preparation is at
the same time protected by an impermeable ce-
ment against dessication and against the introduc-
tion of atmospheric air, all movement among the
bacteria will cease at the end of two minutes, pro-
vided, however, that no air bubble has been im-
prisoned with the liquid."
The influence of oxygen upon the life and de-
velopment of bacteria is also very manifest in an
experiment recently made, and not yet published,
by Toussaint, who has been kind enough to com-
municate it to me.
In studying the development of the spores
of Bacillus anthracis in the moist chamber of
Ranvier, Toussaint has observed the following
curious facts, which offer a striking analogy to
those above mentioned, borrowed from Hoff-
mann. " The bacteria, which occupy the cen-
tral portion of the moist chamber and which
by reason of their situation receive very little
oxygen from the groove, are soon arrested in
their development ; while those which occupy the
borders are long and heaped up in immense num-
bers, those in the centre remain small, formed of
two, four, or five articles, which are easily sepa-
rated from each other; they soon cease to grow
and are not transformed into spores."
Cohn is also as explicit. " There is no doubt,"
118 PHYSIOLOGY OF THE BACTERIA.
he says, " that the complete development of Bacil-
lus, and above all reproduction by means of spores,
is only made under the influence of free access
of air."
We might explain the contradictory facts of
Pasteur by admitting, with Cohn, that the appear-
ance of different roles played by the aerobics
(Bacterium) and the anaerobies (Bacillus) is sim-
ply due to a veritable struggle for existence which
takes place between the microbacteria and the
desmobacteria.
ACTION OF VAKTOUS AGENTS UPON THE BACTERIA.
In this paragraph I shall pass in review the
action of temperature, of movement, and of va-
rious antiseptics.
Temperature. — It is very important to study
the manner in which bacteria comport themselves
under extreme variations of temperature. It is,
indeed, upon the results furnished by these re-
searches that a great part of the arguments op-
posed to the panspermatists by the heterogenists
are based.
We shall consider the influence upon bacteria
of moderate temperatures and of extremes above
and below zero.
Moderate temperatures — that is to say those
which are comprised between 25 and 40° (77 to
104° Fah.) — are generally favorable. The most
favorable has been found to be 35° (95° Fah.)
(Onimus).
DEVELOPMENT OF THE BACTERIA. 119
The degree of resistance to extreme tempera-
tures is very variable, according to the species.
Thus, according to Frisch, a temperature of 45 to
50° (113 to 122° Fah.) is sufficient to kill B. termo,
whilst 80° (176° Fah.) does not kill the " Bacteri-
dies " (Bacillus).
The permanent spores are especially remarkable
by the tolerance which they possess for high tem-
peratures. They have been subjected to 100°
(212° Fah.) (Schwann), 110° (Pasteur) and even
130° (Schrader) without losing their power of
germinating.
We must, however, recognize that the results
of the experimenters offer the greatest diversity,
the result, according to Cohn, of the difficulty of
obtaining an equable distribution of the heat in
the media, which are generally bad conductors.
Cohn has arrived at the following conclusions as
the result of numerous experiments made upon
the Bacillus of hay infusions : —
1. At a temperature of 45 to 50° (113 to 122°
Fah.) the Bacillus still multiplies rapidly, and
forms as usual membranes and spores, while the
other schizophytes existing in the infusion of
hay are at this temperature incapable of multi-
plication.
2. At a temperature of 50 to 55° (122 to 131°
Fah.) all reproduction and development of Bacillus
ceases. It neither forms pellicles or spores; the
filaments are killed, the spores, on the contrary,
preserve, for a longer time (for at least seventeen
hours) the property of germinating.
120 PHYSIOLOGY OF THE BACTERIA.
3. While infusions of hay are generally sterilized
by a temperature of 60° (140° Fah.) or more, pro-
longed during twenty-four hours, certain spores of
Bacillus seem able to endure a temperature of 70
to 80° (158 to 176° Fah.) during three or four
days without losing the power of germinating.
By some experiments made with refrigerating
mixtures, Cohn has ascertained that the bacteria
are not killed by very low temperatures, acting
even during several hours, — 18° for example
(0° Fah.). But they are benumbed at a tempera-
ture of 0° (32° Fah.) and probably at a temperature
a little higher, losing the power of movement and
of reproduction, and consequently their action as
ferments. They preserve, however, their capacity
to resume their activity at a more elevated tem-
perature.
Frisch has pushed the experiment still further
than Cohn. By the evaporation of carbonic acid,
he has produced as low a temperature as — 87 J
( — 123° Fah.) in liquids containing bacteria, with-
out destroying, the vitality of these organisms,
development having subsequently occurred of coc-
cos and of bacteria. Congelation, then, cannot
serve to destroy the organized ferments.
Let us add, however, that if the passage to ex-
treme temperatures is too sudden, there is then an
alteration (destruction ?) of these organisms (Schu-
macher).
Movement. — We would not have consecrated
a paragraph to the action of movement upon
DEVELOPMENT OF THE BACTERIA. 121
bacteria, if Crova had not recently asserted that
movements impressed upon a liquid containing
bacteria completely arrests their development.
This is an assertion in complete opposition to all
that we know of the physiology of these organ-
isms, and which it is difficult to reconcile with the
fact that bacteria may develop even in the torrent
of the circulation.
Compressed Air. — We have just seen the in-
fluence of air, and especially of oxygen, upon the
bacteria. When this agent is in a certain state of
tension, it acts in a different manner. M. Paul
Bert has proved that under a tension of twenty-
three to twenty-four atmospheres all the putrefac-
tive processes depending upon the development of
vibrios cease to occur. Since, the same savant
has found that the anatomical elements and even
the red blood globules are killed by oxygen.
These researches agree well enough with those of
Grossmann and Mayerhauser upon the life of
bacteria in gas. From their numerous experi-
ments it appears that, under the influence of oxy-
gen, there is an exaggeration of the activity of
the bacteria; but if the oxygen is under a pres-
sure of five to seven atmospheres, the bacteria live
from six to twenty hours, then die, and cannot be
resuscitated by atmospheric air.
Ozone causes a definite and almost instantaneous
arrest of movement.
122 PHYSIOLOGY OF THE BACTERIA.
Other gases studied by the same savants have
given the following results : —
Hydrogen at first causes an acceleration of
movement, which is maintained for several days ;
then movement becomes less active, and finally it
ceases altogether.
Carbonic Acid. — Contrary to the facts stated
by Pasteur, this agent was found to paralyze the
bacteria, and reduced them to complete immobility.
If the carbonic acid is displaced by oxygen, the
bacteria resume their activity.
Chloroform. — This substance, according to the
researches of Miintz, arrests the vital phenomena
of organized ferments. Miintz uses this charac-
ter in order to recognize the soluble ferments, upon
which it has no action.
Boracic Acid. — Since the labors of Dumas,
which have demonstrated that boracic acid kills
the inferior organisms by depriving them of their
oxygen, this substance has been employed in vari-
ous circumstances as an antiseptic.
Sulphate of Quinine. — The action of quinine,
either in the state of chlorhydrate or of sulphate,
is not yet well established. The experiments of
Binz, Manassein, Kroevitsch, Bochefontaine, etc.,
have, in truth, given contradictory results.
Carbolic Acid. — The experiments of Manas-
sein have demonstrated that ^th per cent of car-
DEVELOPMENT OF THE BACTERIA, 123
bolic acid is sufficient to prevent all development
of living beings. It is employed with success in
anthrax, in the treatment of wounds, etc.
§ 3. — REPRODUCTION OF THE BACTERIA.
It is well established that the bacteria can mul-
tiply by fission, and reproduce themselves also by
the formation of endogenous spores.
fission. — The multiplication by fission consists
in a transverse division of the cell. When a bac-
terium has attained nearly double its ordinary
length, we see, in the larger species, that the proto-
plasm becomes clearer in the central portion, and a
partition forms in the median line separating the
contained protoplasm into two portions. The par-
tition, at first very delicate, becomes thicker, di-
vides into two, and the two articles separate.
This phenomenon is produced more or less
quickly according to the nature of the medium,
its richness in nutritive material, the temperature,
etc. When the growth is rapid, the new cells form
more quickly than they separate, and are arranged
in chaplets. Very often we only find them in
this form, in strings of two to four cells coupled
together. In some forms the transverse division
is preceded by constriction near the middle of the
cell. Before the two new cells are separated, the
bacterium in this case presents the appearance of
a figure 8, and seems to be a simple cell swollen
at the two extremities.
124 PHYSIOLOGY OF THE BACTERIA.
Under other circumstances, and probably in con-
sequence of a mucus transformation of the walls
of the mother cells, the new bacteria are envel-
oped by a mass of glutinous substance. We have
described these masses under the name of Zo-
oglcea.
The conditions which favor multiplication by
fission are, a certain degree of temperature and
a sufficient quantity of nutritive material. The
higher the temperature, the more rapid is the
segmentation of the bacteria, the more rapid their
multiplication, — that is to say, up to a certain
limit, variable with the species and beyond which
the bacteria are destroyed.
The multiplication decreases when the tempera-
ture is lower, and ceases entirely in the vicinity
of 0° (32° Fah.).
The influence of richness of nutriment is well
seen in artificial cultivation. So long as the bacte-
ria find the necessary aliment, in sufficient quantity,
to form new protoplasm, they multiply with ac-
tivity ; but as soon as the organic matter is de-
voured, they cease to divide, fall to the bottom
of the vessel, where they accumulate, motionless,
and form a deposit more or less abundant.
The multiplication of the bacteria by binary fis-
sion has for result, if nothing occurs to interfere
with the most favorable conditions, the invasion
of the medium by an incredible number of these
little beings, of which we can only form an idea
by calculation.
" Let us suppose," says Cohn, " that a bacterium
DEVELOPMENT OF THE BACTERIA. 125
divides into two in the space of an hour, then in
four at the end of a second hour, then in eight
at the end of three hours, in twenty-four hours
the number will already amount to more than six-
teen millions and a half (16,777,220); at the end
of two days this bacterium will have multiplied
to the incredible number of 281,500,000,000; at
the end of three days it will have furnished forty-
seven trillions ; at the end of about a week, a
number which can only be represented by fifty-one
figures.
" In order to render these numbers more com-
prehensible, let us seek the volume and the weight
which may result from the multiplication of a
single bacterium. The individuals of the most
common species of rod-bacteria present the form
of a short cylinder having a diameter of a thou-
sandth of a millimeter, and in the vicinity of one five
hundredth of a millimetre in length. Let us rep-
resent to ourselves a cubic measure of a millimetre.
This measure would contain, according to what we
have just said, 633,000,000 of rod-bacteria with-
out leaving any empty space. Now, at the end
of twenty-four hours the bacteria coming from
a single rod would occupy the fortieth part of a
cubic millimeter; but at the end of the follow-
ing day they would fill a space equal to 442,570
of these cubes, or about a half a litre. Let us
admit that the space occupied by the sea is equal
to two-thirds of the terrestrial surface, and that
its mean depth is a mile, the capacity of the ocean
will be 928,000,000 of cubic miles. The multipli-
126 PHYSIOLOGY OF THE BACTERIA.
cation being continued with the same conditions,
the bacteria issuing from a single germ would fill
the ocean in five days."
Reproduction by Spores. — The multiplication
by fission, known to the earliest microscopists, has
been until recently the only mode of propagation
admitted by the authors. Thus M. de Lanessan,
in the excellent article which he has devoted to
the bacteria, says that the marvellous resources of
modern science have not yet permitted us to rec-
ognize any other mode of propagation for these
organisms.
However, M. Ch. Robin had already, in 1853,
indicated the presence in Leptothrix buccalis of
little round bodies, " which are perhaps spores."
Pasteur has since, in 1865, recognized that " the
vibrios of putrefaction and of butyric fermentation
present a sort of ovule, or ovoid corpuscle, which
refracts light strongly, either in the extremity
or in the body of the articles." Later, the same
savant, more explicitly, says clearly that these or-
ganisms have two modes of reproduction, — by
fission and by interior spores (" noyaux ").
Towards the same epoch, Hoffmann also pointed
out a reproduction by free cellular formation in
some bacteria. But we must come to the labors
of Cohn, Billroth, and Koch, in order to find pre-
cise observations in this regard.
The formation of spores has been observed
in Bacillus subtilis by Cohn, Bacillus anthracis
by Koch, and in Bacillus Amylobacter by Van
Tieghem.
PLATE vr
'ۥ
FIG. i.
FIG. 2.
FIG. 4.
r^-;Q 'O vO^i
. - io:5>o OoO - -
FIG. «;.
FK;. 3.
'.r. V '
PLATE VI.
FIG. 1. — Micrococci from bottom of culture-solution (rabbit-
bouillon) inoculated with blood of septicaemic rabbit, containing
the same micrococcus in active multiplication, as shown in Fig. 3.
Magnified 1000 diameters by Zeiss's •£$ in. horn. ol. im. objective.
Methyl -violet staining.
FIG. 2. — The same micrococcus cultivated in chicken-bouillon,
inoculated with human saliva. X 1000. Same objective and
staining.
FIG. 3. — The same micrococcus as found in the blood of a rab-
bit, inoculated with normal human saliva. (See p. 237.) X 1000
diameters; Zeiss's ^ in. objective.
FIG. 4. — Micrococci from culture-solution (chicken-bouillon)
inoculated with gonorrhceal pus. X 1000 diameters ; Zeiss's ^ in.
objective. Methyl-violet staining.
FIG. 5. — Micrococci from urine passed into a sterilized glass
vessel and allowed to stand five days, (covered with a watch-glass
and bell-glass; Lister's apparatus, Fig. 5, p. 176,) believed to be
identical with those shown in Fig. 4, and with Micrococcus urece,
Cohn. (See description on p. 75.) X 1000 diameters; Zeiss's
-£% in. objective. Aniline brown staining.
FIG. 6. — Micrococci from culture-solution (malt-extract,) in-
oculated with normal human saliva, probably identical with the
preceding; showing multiplication in two directions. X 1000, by
Zeiss's ^ in. objective. Aniline brown staining.
FIG. 7. — Micrococcus urece, from alkaline urine, showing for-
mation of " chaplets," — torula-chains, — by division in one direc-
tion only. X 1000, by Zeiss's ^ in. objective. Aniline brown
staining.
128 PHYSIOLOGY OF THE BACTERIA.
Cohn, who had in his first publications refused
to the bacteria the property of reproduction by
spores, thinking that the facts observed by Hoff-
mann related to different beings, has verified the
experiments of Koch upon the development of
B. anthraeis, and has himself demonstrated sim-
ilar phenomena in B. sublilis.
In culture experiments made with infusion of
hay, we see, at a certain moment, in the homo-
geneous filaments of the Bacilli very refractive
corpuscles making their appearance. Each of
them becomes a spore, oblong or in the form
of a short filament, highly refractive, and with
well-defined outlines. We find the spores ar-
ranged in a simple series in the filaments. As
soon as the formation of spores has terminated,
the filaments can generally no longer be distin-
guished, and one would say that the spores were
completely free in the mucus; but their linear
arrangement shows always that they are produced
in the interior of filaments. Little by little these
dissolve, being reduced to a fine powder ; and the
spores fall to the bottom of the liquid, where they
are found in abundance. The germination of the
spore does not seem to occur in the same medium;
but if we take a spore from the deposit formed in
an infusion of boiled hay, and transport it into a
new infusion, we see the spore swell up, and a short
tube form itself at one of its extremities : at this
moment it resembles a bacterium with a head.
Soon the very refractive body disappears, the tube
stretches out into a short rod of Bacillus, com-
DEVELOPMENT OF THE BACTERIA. 129
mences to move, and becomes jointed by trans-
verse division.
Koch, in cultivating the bacteria of charbon in
aqueous humor from the eye of the ox, has ob-
served some facts exactly similar, both as to pro-
duction of spores in linear series in the filaments
of Bacillus anthracis and as to the germination of
the spore and the birth of a new rod.
According to Van Tieghem, the development
of Amylobacter is as follows : " The development
of a Bacillus includes four successive periods. In
the first, the body, cylindrical and slender, recently
developed from a spore, stretches out rapidly,
and is partitioned ; the articles soon separate
(B. subtilis), or remain united in long filaments
(B. anthracis). This is the stage of growth and
multiplication, two things which at bottom are
but one.
"Secondly, the articles previously formed, having
ceased to elongate and divide, increase sensibly in
magnitude, becoming the seat of interior chemical
transformations ; and this increase in size operates
according to circumstances, in three different man-
ners, with some intermediate forms. Sometimes
it occurs uniformly throughout the length of the
article, which remains cylindrical ; sometimes it is
localized, either at one extremity, which is swollen
Iik3 a tadpole, or in the middle of the article,
which swells to a spindle shape. This is the stage
of enlargement, or of nutrition, solitary and si-
multaneous, which prepares the following state.
" In the third period or phase of reproduction
130 PHYSIOLOGY OF THE BACTERIA.
there is formed in each article so nourished a
spherical or ovoid spore> homogeneous, highly
refractive, having a dark outline. At the same
time, the protoplasm which occupies the rest of
the cavity disappears little by little, and is re-
placed by a hyaline liquid, which separates the
spore from the membrane; this dissolves in its
turn, and finally the spore is set at liberty. If the
article is swollen in tadpole shape, it is in the ter-
minal swelling that the spore has birth ; if it is
spindle-shaped, it is near the middle ; if it is cylin-
drical, it may be at any point whatever, but is
usually near one extremity. The spore when set
free germinates under favorable circumstances.
At a point where its circumference becomes pale,
it gives out a little tube slightly more slender
than itself, which elongates rapidly and divides.
This fourth period of development or germinative
phase brings us back to our point of departure."
Sporangia. — Finally, not only do the bacteria
develop spores in the interior of their filaments,
slightly modified in form, but we may also observe
the formation of a veritable sporangium contain-
ing many spores. The unpublished observations
of M. Touissant, Professor of Physiology in the
Veterinary School of Toulouse, give this result,
which he has kindly communicated to me.
In cultivating spores of the bacteria of charbon
in the serum of the blood of the dog, under the
microscope, in the warm chamber of Ranvier,
Toussaint has seen the filaments take a transverse
DEVELOPMENT OF THE BACTERIA. 131
diameter almost double the ordinary diameter,
then the protoplasm of the filament to gather
together at certain points, — a fact clearly made
out, as in the parts where the protoplasm was
wanting the bacteria had lost all refractive power.
Finally, at a later period the points occupied by
the condensed protoplasm augment considerably in
volume, and form some ovoid organs more or less
elongated, or swollen into a ball, or in the form
of a gourd at one extremity. In the interior of
these sporangia, from three to six spores afterward
form, clearly defined and highly refractive ; then,
finally, by breaking up of the membranous enve-
lope the spores become free.
Toussaint has also followed in the same appar-
atus — moist and warm chamber of Ranvier — the
mode of germination of the spores. The follow-
ing are the most important facts : —
The spores are at first highly refractive and
animated by brownien movements; at the end
of half an hour to an hour, at a temperature of
37 to 40°, in urine, aqueous humor, or serum, the
spores lose their refractive power, and their brown-
ien movements cease almost entirely; then the
spore assumes an aspect slightly granular, it be-
comes elongated in the direction of its greatest
diameter (they are oval). After two hours of culti-
vation, the bacterium has two or three times the
dimensions of the primitive spore ; the elongation
makes rapid progress, and four to six hours from
the commencement of the cultivation, some may
132 PHYSIOLOGY OF THE BACTERIA.
be found to occupy the entire field of the micro-
scope. From this moment the phenomena which
occur differ according to the conditions in which
the bacteria are placed. Upon the edge of the
air-groove in the moist chamber, the bacteria de-
velop very rapidly, forming an interlaced mass ;
and in sixteen to eighteen hours, spores may be
seen to appear in their interior, — above all, if the
preparation has been exposed to light. Often, in
this case, the transverse partitions of the filament
cannot be seen. If, on the contrary, the bacterium
has not been exposed to light, the spores are a
longer time in showing themselves (ten or twelve
hours more), and almost always division of the
filament precedes their formation. In that case,
a spore usually appears at each end of the seg-
ment in such a manner that the spores belonging
to two successive segments are nearer to each
other than those in the same segment. Often,
also, a spore aborts in a segment (Toussaint).
We have seen above, in speaking of the res-
piration of bacteria, that the same observer has
noted in the course of his experiments some phe-
nomena proving the evident influence of oxygen
upon the development of Bacillus. It is the same
for the formation of spores. And upon this point
Toussaint makes the very just remark that the
phenomena occur in a different manner in culture
experiments and in the human organism. In char-
bon, the bacteria never form spores. They remain
always relatively short, even in the points where
they form extra-vascular masses, and where conse-
DEVELOPMENT OF THE BACTERIA. 133
quently we cannot invoke the movements of the
liquid in order to explain their division. The
bacteria of charbon, then, take but little oxygen
from the tissues : they do not vegetate luxuriantly
in the organism; and certainly, if we judge by a
calculation necessarily approximative, their devel-
opment is seven or eight times less rapid than in
the strongly oxygenated serum of culture experi-
ments (Toussaint).
Polymorphism. — The spores of which we have
traced the genesis constitute those germs of which
the origin has for a long time been misunder-
stood,— those permanent spores or durable spores
(Dauersporen), thus called because of their re-
markable degree of resistance to temperature,
desiccation, and all the agents which kill adult
bacteria or arrest their development.
These " organs " are disseminated in great num-
bers in various media under the form of little
rounded corpuscles absolutely similar to the micro-
cocci from which it is absolutely impossible to
differentiate them. It is, indeed, very probable
that the greater part, if not all of these organisms,
are the spores of filiform bacteria.
In the impossibility of recognizing these forms
so nearly related, of referring them to such or
such a determined organism, the attempt has been
made to cultivate them, in order to follow their
development. We have just seen the results of
this cultivation for the Bacillus ; but, in the hands
of the greater number of experimenters, the re-
134 PHYSIOLOGY OF THE BACTERIA.
suits of such culture experiments are far from
being so certain. Not having succeeded in re-
moving them completely from the invasion of for-
eign germs, the greater number have seen the
most diverse forms develop themselves, and from
this have inferred the most remarkable transfor-
mations.
Thus, Hallier pretends to have observed the
transformation of Micrococcus into various fungi,
such as Mucors, Ustilago, etc. The M. of vaccinia
comes from Torula rufescens, which is itself a
phase of development of Ustilago carbo ; the M.
of human variola is derived from a fungus having
sporangia and pycnidia, related to Stemphylium
sporidesmium ; that of the variola of animals
from Cladosporium (Pleospora) herbarum ; the
M. of the blood of scarlatina belongs to the
g. Tilletia; those of glanders and of syphilis
from a Coniothecium, etc. In the same way Letz-
erich has referred the M. of diphtheria to another
Tilletia, the T. diphtkerica.
The transformation of bacteria into " levures "
(yeast fungi), and these into Penicillium, has been
admitted by Hallier, Trecul, and others. But the
researches of Brefeld and de Seynes have shown
us that this is far from being demonstrated ; in-
deed, in his numerous cultivations, de Seynes has
never been able to verify such an affiliation ; and
Nageli in his turn has never been able to obtain
a transformation of schizomycetes into budding
fungi.
It is the same as regards the transformation of
DEVELOPMENT OF THE BACTERIA. 135
bacteria into moulds and mildews. In some recent
cultivations of moulds, made with care, Nageli has
never observed the formation of schizomycetes,
and reciprocally. Are we not permitted to be-
lieve, now that we know of the formation of
sporangia among the bacteria, that the micro-
scopists who sustain a polymorphism so extended,
have taken these organs, of which they have not
been able to follow exactly the development, for
the sporangia of Mucorini? This explanation is
the more admissible as Trecul has seen the bac-
teria " swell up, and transform themselves sepa-
rately," a phenomenon quite identical to that ob-
served by Toussaint.
En resume. The only change of form well
demonstrated in the present state of science, and
the only one which can be compared to natural
polymorphism, such as it exists in a great number
of fungi, consists in the transformation of spores
into Bacteria, Bacteridia, Vibrios, etc., and in the
different modes of grouping that the cells of bac-
teria take in becoming zooglcea, mycoderma, lepto-
thrix, etc. To go further would be to lack pru-
dence and scientific criticism.
136 PHYSIOLOGY OF THE BACTERIA.
CHAPTER II.
DEVELOPMENT OF THE BACTEKIA IN
DIFFERENT MEDIA.
IN studying the conditions of life and of develop-
ment of bacteria in the different media, natural
and artificial, in which they are met, we will con-
sider the actions which they determine (or that
they accompany) as particular cases of their nutri-
tion and of their reproduction. We will con-
stantly take, then, their normal physiology as our
point of departure ; and we will try to explain in
this way the phenomena, so diverse, with which they
are associated, — fermentations, putrefactions, con-
tagion of infectious maladies, etc.
It is especially interesting to study the role of
bacteria in non-nitrogenized chemical media, where
they accompany the phenomena called fermenta-
tion, properly so called ; in nitrogenized media,
vegetable or animal, which they transform, as a
result of special fermentations, which constitute
putrefaction ; in the human organism, where they
accompany frequently, if not always, the develop-
ment of certain affections having special charac-
ters. This will be the object of so many para-
graphs
THE BACTERIA IN DIFFERENT MEDIA. 137
§ 1. — HOLE OF BACTERIA IN FERMENTATIONS.
We say that a liquid is fermenting whenever
modifications occur in its chemical constitution, as
a result of the nutrition of organized beings.
Two kinds of fermentation are commonly distin-
guished. In the first group (false fermentations)
are arranged those which are produced by soluble
quarternary substances (diastase, soluble ferments)
secreted by living cells, from which they may be
separated in order to study their action upon fer-
mentable liquids. This action is comparable to that
of certain mineral acids, which operate in the same
manner, either by the breaking up of molecules
with addition of water or by the phenomena of
hydration. Veritable chemical reagents, when
these substances are once precipitated from their
solutions, purified and dried, they preserve their
properties indefinitely. A sufficient elevation of tem-
perature seems to destroy the edifice of their mol-
ecule ; for they lose all their specific power after
having been subjected to a temperature more or less
elevated, but always inferior to 100° (212° Fah.).
In the second group (true fermentations) are
joined all the phenomena of chemical modifica-
tion which appear intimately united to the devel-
opment of inferior organisms, — algse or fungi
(figured ferments). Compressed oxygen by kill-
ing these ferments, and chloroform by suspending
their vital functions, arrest the progress of these
fermentations, while the same agents do not mod-
138 PHYSIOLOGY OF THE BACTERIA.
ify at all the action of soluble ferments. Accord-
ing to Duinas, borax has, on the contrary, the
property of entirely destroying the activity of
soluble ferments without absolutely preventing
certain true fermentations, — for example, the al-
coholic fermentation of glucose. We will see fur-
ther on that this property of borax has been
utilized in the treatment of catarrh of the blad-
der and of certain virulent affections.
Although at first view these two groups of phe-
nomena seem very different, they may, however,
be compared the one with the other. Without
speaking of the ammoniacal fermentation of urine,
which, as we shall shortly see, may be arranged in
either of these groups, we may admit that the only
difference between these two series of chemical
modifications consists in the fact that in one case
the true fermentations being the last term in the
interior nutrition of the cell have their seat in
the interior of the cell itself ; while in the other
the first terms of nutrition are always extra-cellu-
lar phenomena, having for effect, as Cl. Bernard
has shown, to render assimilable or diffusible in the
interior of the organism the aliment necessary to
the development of every organized being (trans-
formation of starch into glucose, of sugar into
glucose, emulsion of fats, liquefaction of albumi-
noid substances).
The study, from a chemical point of view, of
these phenomena of nutrition, of these fermenta-
tions, since such is their name, has not yet made
much progress, and it would be difficult to make a
rational classification of them in the present state
THE BACTERIA IN DIFFERENT MEDIA. 139
of our knowledge. I will not then seek to clas-
sify them, but will content myself with describ-
ing them successively, commencing with the best
known. I shall only speak of the fermentations
caused by the development of bacteria, leaving,
consequently, the fermentation which has been
best studied, — the alcoholic. I adopt the follow-
ing order : —
1. Acetic fermentation of alcohol.
2. Ammoniacal fermentation of urine.
3. Lactic, viscous, and butyric fermentations of sugar.
4. Putrefaction, or nitrification.
Acetic fermentation. — The transformation of
wine into vinegar is a phenomenon long known
and utilized. From a chemical point of view, this
transformation is due to oxydation of the alcohol.
The following formula represents this reaction : —
C2H6O + O2 = C2H4O2 + H2O.
The agent of this oxydation is a micro-organism
called Mycoderma aceti. It belongs to the group
of the microbacteria, and we have already given
the botanical description of it (page 83) ; but its
development presents some interesting peculiar-
ities which we think it proper to indicate in the
language of M. Duclaux : —
" These little beings reproduce themselves with
such rapidity that by placing an imperceptible germ
upon the surface of a liquid contained in a vat
having a surface of one square metre, we may
see it covered, in from twenty-four to forty-eight
hours, with a uniform velvety veil. If we suppose
140 PHYSIOLOGY OF THE BACTERIA.
that there are three thousand cells in a square mil-
limetre, which is below the truth, this will give
for the vat three hundred milliards of cells pro-
duced in a very short time."
" The Mycodermi aceti is not always the same.
Usually it forms upon the surface of a liquid a
soft-looking veil, smooth at first, then wrinkled,
which is with difficulty submerged and moistened.
If a glass rod is plunged into the liquid, it pierces
this veil ; and when it is withdrawn, a portion re-
mains attached to the rod ; aaid the opening made
immediately disappears, being occupied by the veil
which seems never to have room enough in which
to extend itself. In some unpublished experi-
ments I have frequently observed another form of
veil, dryer, finer, and sometimes showing prismatic
colors. This veil does not wrinkle, but is covered
with crossed undulations, having sharp edges,
which recall the surface of a honeycomb. Sowed
upon the surface of various liquids, it reproduces
itself identically, and it is difficult not to consider
it a different form of the preceding. Finally, I
have also met a species of mycoderma producing
well-developed veils, but having scarcely any acet-
ifying power, and reproducing itself with this
character."
"It is difficult to distinguish these forms the one
from the other, by the microscope, because of their
minuteness. We may, however, say that the second
which I have described is sensibly smaller than
the first, and the third more attenuated than either
of the others. However, the differences are feeble."
This veil is called the mother of vinegar. The
THE BACTERIA IN DIFFERENT MEDIA. 141
liquid in which this mycoderma is cultivated should
be a little acid, containing one-half per cent of
acetic acid, for example. Under these conditions
the Mycoderma vini (a species of Saccharomycete),
the formation of which should be avoided, finds
conditions unfavorable to its existence. Indeed,
this second organism, commonly called flowers of
wine, has an action quite different from that of
the Mycoderma aceti. It consumes the alcohol
entirely, transforming it into water and carbonic
acid : it also consumes the acetic acid. We must
sow the M. aceti, if we do not wish to see the M.
vini develop in its place, as the germs of the latter
seem more widely diffused in the air.
In order that the acetification may occur, the
oxygen of the air is necessary. Once submerged,
the M. aceti develops, but no longer produces
acetic acid. It is even probable that it consumes
the acetic acid already formed, reducing it to the
state of water and carbonic acid. It is the same
when, developing upon the surface, it has trans-
formed all the alcohol. " In effect, it is not then
arrested in its work ; and without changing form
or mode of action, it carries the oxygen of the air
to the acetic acid which it has produced, transform-
ing it into carbonic acid and water. If we add some
alcohol to the liquid, the phenomena change : the
acid is respected, and the alcohol is transformed
anew into acetic acid " (Duclaux). According to
the experiments of Mayer, the maximum of aceti-
fying power is obtained between 20° and 30° (68°
to 86° Fah.), and this power is lost below 10° (50°
Fah.) and above 35° (95° Fah.).
142 PHYSIOLOGY OF THE BACTERIA.
Ammoniacal Fermentation of Urine. — When
urine is freely exposed to the air, we perceive at
the end of a short time that it has become strongly
ammoniacal. The urea is transformed into carbon-
ate of ammonia by the addition of water : —
CO(NH2)2 + H20 = CO2 + 2NH3.
Miiller suspected that the deposit of altered
urine, of which Jacquemart had already recognized
the particular activity, was an organized ferment,
but this was only an induction drawn from the
analogy with beer yeast. Pasteur showed that
this sediment is formed of a mass of spherical
globules, united in chaplets, which he considers the
agent of ammoniacal fermentation. These glob-
ules are Micrococcus urece, Cohn, which we have
already described (page 75).
This bacterium lives in the interior of the liquid,
and not on the surface like the Mycoderma aceti.
Acidity is an obstacle to its development ; alkalin-
ity, on the contrary, favors it within certain limits.
Van Tieghem has even seen the fermentation con-
tinue until the liquid contained thirteen per cent
of carbonate of ammonia.
What is the mechanism of this fermentation ?
M. Musculus has shown that we may obtain
from altered urine a soluble ferment upon adding
to it highly-concentrated alcohol : a precipitate is
formed, which may be filtered and dried. This
precipitate, not at all organized, transforms urea
into carbonate of ammonia. A temperature of
80° (176° Fah.) destroys it. This diastase appears,
THE BACTERIA IN DIFFERENT MEDIA. 143
then, to be a secretion of the Micrococcus urece ;
and perhaps the role of the bacteria is limited, in
the phenomena of fermentation, to the formation of
this secretion alone. The ammoniacal transforma-
tion of urine would consequently enter into the
group of fermentations by the varieties of diastase.
According to Arnold Hiller, if carbolic acid be
added to urine, it does not become alkaline ; on
the contrary, the acidity is even augmented, and
that notwithstanding a considerable number of
bacteria which develop in it. Has the carbolic
acid killed the Micrococcus urece, leaving the field
free to other organisms capable of living in an
acid medium, and of producing other transforma-
tions of the constituents of the urine ? In the
•memoir which we here cite, the author, resuscitat-
ing the ancient opinion of Liebig, wishes to dem-
onstrate that the decomposition of dead organic
matters, and putrefaction in general, are phenom-
ena purely chemical, — these decompositions being
determined by the presence of organic substances,
themselves undergoing transformations.
We will not stop to consider these views, long
since refuted : the experiments upon which they
are founded are easily criticised. It is sufficient
for me to say that they are in formal opposition
with all the observations contained in modern
works upon this question.
It is especially in relation to ammoniacal fer-
mentation that the question of spontaneous gen-
eration has been discussed. We have already
seen the results arrived at, and will not return to
144 PHYSIOLOGY OF THE BACTERIA.
this subject. Let us, however, mention before
closing an interesting work by MM. Cazeneuve
and Livon, in which are reported some experiments
which prove that urine never ferments in a healthy
bladder.
Lactic, Butyric, and Viscous Fermentations of
Sugars. — Saccharine liquids, left to themselves,
are susceptible of divers fermentations, which may
occur separately or simultaneously. Those which
have been best studied are three, — the lactic, the
butyric, and the viscous fermentations. We will
describe them successively.
1. Lactic Fermentation. — Under the probable
influence of a bacterium (ferment lactique of Pas-
teur) glucose and the substances susceptible of
furnishing it, such as mannite, malic acid, etc., are
transformed into lactic acid.
From a chemical point of view, there is in this
nothing more than a molecular change, lactic acid
having the same composition as glucose.
Taken in mass, the lactic ferment resembles
beer-yeast ; its consistence is, however, a little more
viscous, and its color more gray. But under the
microscope, the aspect is very different, as we have
seen in describing Bacterium lineola.
An interesting point concerning this fermenta-
tion is the action of acids upon the bacteria which
produce it (presumably). As soon as the medium
becomes acid, even by the lactic acid produced, the
transformation is arrested. It resumes its course,
if chalk or carbonate of soda is added to the
liquid.
THE BACTERIA IN DIFFERENT MEDIA. 145
The most suitable temperature seems to be 35°
(95° Fah.).
We know but little about this fermentation.
" It merits, however, to be better studied. It
is this which causes the spontaneous coagulation
of milk : sugar of milk is transformed into lactic
acid, which coagulates the caseine. We often see it
occur in beef juice or in sour starch water; it must
play a part in the formation of sour krout, and
intervenes very certainly, and perhaps more than
the alcoholic fermentation, in the preparation of
bread. Finally, it very easily invades beer, which
of our domestic drinks is most exposed, because of
its slight acidity, to become the seat of this fer-
mentation. All of these facts render it interest-
ing, so much the more as it is rarely exempt from
complication, and is frequently accompanied, for
example, by a commencement of butyric fermenta-
tion, far more disagreeable in its products " (Du-
el aux).
2. Butyric Fermentation. — This is, in fact, al-
ways preceded by a lactic transformation, and it is
by an ulterior modification that the lactic acid
produces the butyric acid. The organism which
accompanies it is a bacterium very nearly allied
to Bacillus subtilis, Cohn.
The reaction represented by the phenomena,
from a chemical point of view, is the follow-
ing:—
2CSH6O3 = C4H8O2
lactic ac. butyric ac.
146 PHYSIOLOGY OF THE BACTERIA.
According to Pasteur the butyric ferment be-
longs to his class of anaerobies.
This fermentation resembles putrefaction in a
great many particulars. Indeed some authors in-
clude it under the same head.
3. Viscous Fermentation. — Wines often change
so that they contain a mucilaginous substance and
mannite. This viscous matter has the same com-
position as gum or dextrine (C6H1005) ; at the
same time it disengages carbonic acid.
In the fermenting liquid, we find an organism
which is not yet sufficiently studied. " There are
chaplets of little spherical bodies, of which the di-
ameter varies sensibly, according to the kind of
wine attacked by this malady (Pasteur).
Pasteur has proposed the following formula : —
25(C12H22O11) + 25H2O = 12(C12H20O10) +
gum.
24(C6HI4O6) + 12C02 + 12H2O.
mannite.
which represents the phenomena well enough as it
usually occurs. There is produced in the vicinity
of 51.09 of mannite and 45.5 of gum for one hun-
dred parts of sugar. But sometimes the gum ex-
ceeds the mannite in quantity. In this case,
according to Pasteur, we can always verify in the
liquid the presence of a larger ferment of a differ-
ent nature ; and the same author adds that, per-
haps, in this case the increased production of gum
results from the presence of this second ferment,
which transforms the sugar only into gum, without
THE BACTERIA IX DIFFERENT MEDIA. 147
any correlative formation of mannite. But this
ferment has never been isolated. M. Monoyer has
explained the variation in the proportion of gum
in another manner (see his thesis for the doctorate
in medicine. urg, 1862).
"White wines are more subject than red wines to
this fermentation, called graisse des vi?is. Accord-
ing to M. Francois, the absence of tannin in the
white wines is the cause of this disease, and it
may be prevented by adding this substance. This
remedy is even very highly appreciated in cham-
pagne, according to Pasteur. What is the exact
action of the tannin upon the gummy ferment ?
The only means of knowing is by cultivating this
ferment in a state of purity and treating it with
this agent.
We have united together the lactic, butyric, and
viscous ferments, because all three manifest them-
selves in the same liquids, — wines, beer, sweetened
water, etc. ; and because they have for effect the
transformation of glucose. We ought to say a
word here of some other inferior organisms, per-
haps bacteria, observed also in the same liquids,
but which have not been as well studied. Not
only are they not known systematically, but we
do not know precisely what is their chemical ac-
tion upon the elements of the medium which
nourishes them. I shall only enumerate them.
1. Ferment of Turned Beer (Pasteur). — -'-These
are rods or filaments, simple or articulated into
chains of variable length, of about 1 p. diameter.
148 PHYSIOLOGY OF THE BACTERIA.
A high power shows them divided into a series of
shorter rods, scarcely born, not yet mobile at the
articulations, which are scarcely indicated."
2. Micrococcus of a beer, having a particular
acidity, distinct from that of beer pique, having
an acetic odor. " It consists of grains resembling
little spherical points jointed by pairs or in fours
square " (Pasteur), etc.
§ 2. — HOLE OF THE BACTERIA IN PUTREFACTION
AND NITRIFICATION.
While in the fermentations which we have just
passed rapidly in review, we have always been
able to study, at least summarily, the chemical
action of the different organisms, we are now
about to find ourselves in presence of phenomena
far more complex. We will have to consider a
great number of these vegetables at work, without
its being possible to assign to each its role, or to
say what is its function. The agent of the nitric
fermentation has not as yet even been seen, and it
is only by analogy that we class this nitrification
with the true fermentations.
It is not only because of the obscurity which
still exists in regard to a great number of peculiar-
ities of these two phenomena, that we have united
them in the same study. From the point of view
of the circulation upon the surface of our globe
of the elements essential to the constitution of
organisms, they play an analogous role, although
opposite the one to the other.
THE BACTERIA IN DIFFERENT MEDIA. 149
Let us consider, for example, nitrogen in plants.
This element, of which the atmosphere is the res-
ervoir, does not enter directly into combination, as
does oxygen, with the other elements which with
it are to constitute the immediate principles of the
tissues. The chemical properties of nitrogen may
be characterized in two words, — great resistance
to entering into combination when it is free, and
great facility, on the contrary, in passing from one
combination to another when once it has associated
itself with other elements.
The circulation of nitrogen in a state of com-
bination upon the surface of the globe is also an
interesting question of general physics, as well as
the circulation of carbonic acid, of water, and of
the air.
Let us seek to sketch the march of this cir-
culation.
Whence comes the ammonia which is found in
the sea, in the clouds which come to us from equa-
torial regions, in the dust of the air ? The only
known source is the fermentation of organic mat-
ters out of reach of the oxygen of the air. It is
to this sort of fermentation that we owe the for-
mation of peat and the immense masses of com-
bustible minerals which have formed during nearly
all the geological periods. We see this sort of fer-
mentation develop itself when we expose an or-
ganic liquid to the air, but. only in the inferior
part of the liquid, the oxygen which is dissolved
near the surface being arrested in the superficial
zone, where a very different fermentation occurs.
150 PHYSIOLOGY OF THE BACTERIA.
The latter is essentially oxidizing ; the material is
almost completely burnt, forming water and car-
bonic acid ; at the inferior part, on the contrary, a
reduction is produced so energetic that hydrogen
is disengaged. The metallic sulphates are there
transformed into sulphites, and even crystals of
sulphur are sometimes found (see the history of
the Beggiatoa, page 91).
We see then the source of the ammonia, which,
distributed upon the soil by the winds and the rains,
becomes a powerful fertilizer. Now, vegetables do
not absorb nitrogen under the form of ammonia, but
under the form of nitric acid. How is this transform-
ation of ammonia into nitric acid effected ? The
observations of Erdmann, Mensel, and T. Phipson
show that in the phenomena of destructive putre-
faction, nitric acid, far from being produced, is on
the contrary reduced to the state of nitrous acid ;
on the other hand, Th. Schloesing and A. Miintz
conclude from their experiments that in the pu-
trefactions essentially oxidizing produced by Peni-
cillum glaucum, Aspergillus niger, Mucor mucedo,
etc., there is no formation of nitric acid. But,
according to these authors, nitrification is a spe-
cial phenomenon which takes place in every soil
sufficiently loose to permit a free circulation of air,
and of which the agent is a micro-organism. This
organism has not yet been perceived, it is true ;
and it is evident that it would be difficult to seek
and observe, because of its peculiar situation.
But the action of chloroform upon nitrification
tends to prove that the agent of this process is
THE BACTERIA IN DIFFERENT MEDIA. 151
truly an organized ferment. Indeed, chloroform,
this anaesthetic, suspends nitrification, and seems
even to kill the ferment.
Leaving, then, this phenomenon, but little
known, we may distinguish in the agents of pu-
trefaction, or more generally of fermentation, two
groups of micro-organisms, — one oxidizing, the
other reducing.
The first are observed upon the surface of
liquids undergoing putrefaction. We may distin-
guish a great number of forms, — Bacterium termo,
Monas crepusculum, Spirillum, etc. We ought
also to include Mycoderma aceti, which, like the
others, vegetates on the surface of liquids, and
a great number of organisms of which we cannot
speak here.
The second are met, on the contrary, in the
interior of liquids or of fermentable bodies ; they
are analogous to the butyric and lactic ferments,
and perhaps to the other agents of diseases of
wine and beer previously enumerated.
En resume, the little beings which we have been
considering have an important role: they cause
the return of dead organic matter to the atmos-
phere and to water.
"Without them, organic matter, even exposed
to the air, would not be destroyed or would be
transformed with extreme slowness, in consequence
of a slow combustion produced by oxygen. With
them, on the contrary, its destruction takes a
rapid march and becomes complete. If, then, the
equilibrium is maintained between living nature
152 PHYSIOLOGY OF THE BACTERIA.
and dead nature, if the air has always the same
composition, if the waters are always equally fer-
tilizing, it is thanks to the infinitely minute agents
of fermentation and putrefaction" (Duclaux).
But the role of bacteria is not limited to this.
" They invade also the living organism," says Du-
claux, " and bring in their attack this double char-
acter of infinite smallness in the apparent means
and powerful destructive energy in the results.
From this source come diseases of which medicine,
not long since, did not know the cause, and which
she only commences to refer to their veritable
origin. For those who are au courant with the
first steps which she has made in this new line of
research, with the fecundity of her first glimpses,
with the richness of her first results, it is not
doubtful that she will soon succeed in demonstrat-
ing the parasitic nature of the gravest epidemic
maladies "
PART THIRD.
TECHNOLOGY.
PART FOURTH.
GERMICIDES AND ANTISEPTICS.
PART FIFTH.
BACTERIA IN INFECTIOUS DISEASES.
PART SIXTH.
BACTERIA IN SURGICAL LESIONS.
BY DR. G. M. STERNBERG.
PART THIRD.
TECHNOLOGY.
OWING to their minute size and the difficulties at-
tending their study, the Bacteria received but
little attention from naturalists prior to the dis-
covery by Davaine of the anthrax bacillus (Com-
municated to the French Academy of Sciences in
1863).
Since this date, very great progress has been
made in 'our knowledge of these minute plants;
and this progress has been due, to a consider-
able extent, to the labors of physicians rather
than to those of botanists, who, as a rule, have
been inclined to make light of the importance
attached to this and subsequent discoveries re-
lating to the presence of parasitic micro-organ-
isms in the blood or tissues of man and the lower
animals while suffering from certain infectious dis-
eases. We are greatly indebted, however, to the
German botanists, Cohn and Nageli ; and to the
distinguished French chemist Pasteur must be
awarded the foremost place among those who have
contributed to our knowledge in this direction.
156 TECHNOLOGY OF BACTERIA.
As in other branches of science, progress has to
a great extent been dependent upon improvements
in technique. These relate especially to methods
of cultivation, and to the staining, mounting and
photographing of bacterial organisms.
The object of the present chapter is to give as
concise an account as possible of the technology
as at present perfected, and as employed by the
most successful modern investigators.
§ 1. — METHODS OF CULTIVATION.
For the solution of many problems relating to
the life-histories and physiological functions of the
various species of Bacteria, it is essential that
a " pure culture " be obtained and maintained
through successive generations by the inoculation
of fresh portions of a suitable culture-medium.
Evidently this requires not only pure stock to
commence with, but also a culture-medium free
from living organisms — sterilized, — and the ex-
clusion of floating atmospheric germs.
Methods of Obtaining Pure Stock. — Various meth-
ods have been devised for the purpose of isolating
a single species when mingled, as is commonly the
case, with many others. Lister proposed to ac-
complish this by diluting the material containing
a number of distinct species — e. g. a drop of
human saliva or of broken-down beef tea which
has been freely exposed to the air — with a steril-
METHODS OF CULTIVATION. 157
ized fluid until there shall be an average of less
than one living germ to each drop of fluid. %If
now we inoculate numerous separate portions of a
sterilized culture-medium with a single drop, each,
of this diluted stock, it is evident that some por-
tions may receive no living seed, others may have
germs of two or more species, and others may
chance to have one or more germs of a single
species. In the latter case, the multiplication of
these germs under conditions which excluded the
possibility of contamination from without would
give us a pure culture of this particular species.
So far as the writer is aware this method has not
been employed, except in a limited number of
experiments made by Lister himself in order to
demonstrate its feasibility. No doubt it may be
successfully employed, but it would involve a
great expenditure of time, and success would
probably be the exception and failure the rule,
owing to the difficulty of estimating the exact
amount of dilution required in the first instance,
and because of the element of chance, which is an
essential feature of the method.
The same result is accomplished more expedi-
tiously by the method of Koch, the essential fea-
ture of which consists in using a solid sub-stratum
as the culture-medium, upon which the mixed
micro-organisms are distributed. A sufficient quan-
tity of gelatine (3 to 5 per cent.) is added to a
suitable culture, -fluid to cause the mixture to jellify
when cooled. While still warm, this gelatine cul-
158 TECHNOLOGY OF BACTERIA.
ture-fluid is poured upon glass slides, to which it
adheres when cool in the form of a semi-solid
layer. Upon this the mixed bacteria are dis-
tributed by means of a needle, the point of which
is lightly drawn across the surface, after having
been charged with seed by dipping it into the
stock-solution a biological analysis of which is
desired — e. g. broken-down urine or beef tea.
The different micro-organisms are distributed by
this method along the track of the needle, and the
subsequent multiplication of each germ in situ,
when the slide has been left for a day or two in
the culture-oven, produces a little collection of the
particular species to which it belongs, which may
be recognized under the microscope or even by
the naked eye.
A pure culture is obtained by inoculating a
sterilized culture-fluid with seed, transferred with
due precautions, from one of these little masses
formed along the track of the needle.
Another method which suggests itself, and will
doubtless be found useful in certain cases, depends
upon the difference as to reproductive activity
manifested by different species of bacteria, and
upon the fact that a culture-medium, or conditions
as to temperature, favorable for the development
of one species may not be for another. By taking
advantage of these physiological peculiarities we
may succeed in excluding all but a single form,
by one or more culture experiments, notwithstand-
ing the fact that our stock was impure at the
METHODS OF CULTIVATION. 159
outset. It is evident that if one species multiplies
more promptly and rapidly than the others which
are associated with it, it will soon be present in
excess in a culture-fluid inoculated with the com-
mingled species, and that by using this stock to
start a second culture before other forms have
time to multiply, repeating the operation if neces-
sary through a series of cultures, we shall at last
exclude all except the single species which has
taken precedence by virtue of its rapid multipli-
cation.
In the same way we may take advantage of
conditions relating to the composition of the cul-
ture medium, and to the temperature at which it
is maintained after inoculation with impure stock.
When the conditions are most favorable for the
development of a particular species, it is evident
that this will take precedence over others with
which it is associated. And it may happen that
conditions extremely favorable for one are entirely
unsuited for other species which, accordingly, do
not multiply at all.
We have examples of this in the experiments
which have been made upon living animals, which
may be considered culture-experiments, in which
the blood of the animal serves as a culture-fluid,
and in which the temperature maintained is neces-
sarily that of the species used in the experiment.
Thus in the form of septicaemia in the mouse,
which has been studied by Koch, a drop of putrid
blood " containing bacteria of the most diverse
160 TECHNOLOGY OF BACTERIA.
forms irregularly mixed together," injected be-
neath the skin of the animal, gives rise to an
infective disease characterized by, and dependent
upon, the presence of a multitude of minute ba-
cilli in the blood and tissues. In this case, it is
evident that the conditions are favorable for the
multiplication of this species, and not for the
others associated with it in the drop of putrid
blood introduced into the living culture-apparatus.
This experiment enables us to secure a pure cul-
ture of this particular bacillus; for the smallest
quantity of blood taken from the vessels of the
animal, immediately after its death, contains it in
abundance, and may be used to inoculate a steril-
ized culture-fluid. In the same way, if we inocu-
late a rabbit with a drop of human saliva, which
contains a variety of bacteria, one species only
multiplies freely and invades the blood of the ani-
mal, producing a fatal infectious disease. This is
a micrococcus of oval form and having peculiar
characters. (Fig. 3, Plate VI.) By introducing a
little of the blood of a rabbit, just dead as the
result of such an inoculation, into a sterilized cul-
ture-fluid, we obtain a pure-culture of this micro-
coccus, which may be maintained indefinitely
through successive generations from culture-tube
to culture-tube, or from rabbit to rabbit, thus show-
ing that this micrococcus is a distinct species, as
it "breeds true."
Having obtained pure stock by one of the
methods mentioned, success hi cultivating the spe-
METHODS OF CULTIVATION. 161
cies contained in it will depend upon the use of a
suitable culture-medium, and the maintenance of
favorable conditions as to temperature and a suf-
ficient supply of oxygen, if required.
Natural Culture-Fluids. — The natural culture-
fluids which are available for use are blood, milk,
urine, and aqueous humor from the eye of one of
the lower animals.
All of these have been used, and all may be
obtained in a pure state from the living animal by
adopting proper precautions.
Blood. — The observations of numerous experi-
menters prove that the circulating fluid in healthy
animals is free from all bacterial organisms. To
obtain a supply for experimental purposes it must
be drawn directly from the vessels into a sterilized
receptacle. This may be accomplished by means
of a glass tube drawn out at each end to form a
capillary tube, hermetically sealed at each extrem-
ity and thoroughly sterilized by heat. Such a
tube is to be filled by exposing a superficial vein
of sufficient size, and introducing one of the ca-
pillary extremities within the vessel through a
very small orifice made through its walls. The*
end of the tube is to be broken off within the
vessel, after which the outer end may also be
broken, to allow the contained air to escape as the
tube fills with blood. This will not be necessary,
however, if a partial vacuum has been formed by
11
162 TECHNOLOGY OF BACTERIA.
sealing the capillary extremities in the flame of an
alcohol lamp while the tube was still quite hot.
Both extremities are sealed as expeditiously as
'possible as soon as the tube is withdrawn from the
vessel. It is evident that to obtain a larger quan-
tity of blood, a flask having two necks bent at a
right angle and drawn out to form capillary tubes
may be substituted for the simple straight glass
tube. (See Fig. 1.)
Fig 1.
The color of the blood, due to the presence of
the red corpuscles, and the fact that these ele-
ments, after a time, form a granular debris which
might interfere with the recognition of minute
micrococci, are objections to the use of this
fluid in culture experiments. Blood-serum, how-
ever, is free from these objections, and is a valua-
ble culture-medium. This may be obtained from
a flask, like that shown in Fig. 1, by transferring
the serum, after it has separated from the clot, to
"small culture-flasks like those described on page
176 (Fig. 5), by the method there detailed. To
accomplish this, one of the arms of the larger
flask is broken off to admit the capillary extrem-
ity of the smaller one. By skilful manipulation
a number of these may be filled with transparent
METHODS OF CULTIVATION. 163
serum with but little chance of contamination by
floating atmospheric germs.
Blood-serum obtained without these special pre-
cautions may also be used by resorting to the
method of Koch for sterilizing it subsequently to
its separation from the clot. This is accomplished
by introducing it into test-tubes from which at-
mospheric germs are excluded by a plug of cotton,
or into hermetically sealed culture-flasks, like those
described on page 176, and exposing it for an hour
daily to a temperature of 58° C. (136.4° Fahr.) for
a period of six days. This method insures the de-
struction of living germs contained in the blood-
serum without coagulating the albumen, which
would destroy its value as a culture-fluid. If a
solid culture-medium is desired, the blood-serum
is subsequently subjected to a temperature of
65° C. (149° Fahr.) for several hours. A solid,
transparent, jelly is produced by this method,
which is the material upon which Koch cultivated
the tubercle bacillus in his experiments relating to
tuberculosis.
Milk. — The experiments of Lister, Roberts and
Cheyne have demonstrated that milk, as it exists
in the udder of the cow, is free from the germs
of fermentation or putrefaction, and may be pre-
served indefinitely without undergoing change, if
proper precautions are taken to introduce it into
sterilized flasks without contamination by organ-
isms detached from the external surface of the
164 TECHNOLOGY OF BACTERIA.
body of the animal or by floating atmospheric
germs. It is difficult to accomplish this, however,
and in practice it will be found that inilk, although
a suitable culture-fluid for various organisms, is not
commonly available, owing to the difficulty of ob-
taining it from its source free from contamination,
and to the fact that it is a difficult fluid to
sterilize.
Urim. — Pasteur, Lister, the present writer, and
several other experimenters have succeeded in
obtaining urine, directly from the bladder, free
from bacterial contamination, and which, conse-
quently, did not undergo any change from being
kept, although exposed freely to the air — filtered
— and to a temperature suitable for inducing the
different forms of fermentation which this fluid
undergoes when no precautions are taken to ex-
clude the micro-organisms to which these changes
are due.
In man, and doubtless in the lower animals also,
the orifice of the urethral canal is constantly in-
fested with bacteria of different species, whereas
the deeper portion of the canal and the bladder
are quite free from them. This is proved by
microscopical examination, and by the fact that
urine free from bacteria may be obtained by
taking the precaution to destroy those located in
the vicinity of the meatus urinarius by means of
a suitable disinfectant.
The writer has on several occasions repeated
METHODS OF CULTIVATION. 165
with success the experiment of Lister, the essen-
tial feature of which is the thorough cleansing
and disinfection of the urethral canal by means
of a solution of carbolic acid (5 per cent). The
glans should also be washed with the same solu-
tion ; after which the urine is passed into a glass
flask or test-tube which has been sterilized by
heat. This is at once closed with a plug of
cotton.
Urine has been extensively used as a culture-
fluid, and is well suited for the development of
many species of bacteria; and especially for the
micrococcus, which has been shown by Pasteur to
be the cause of the alkaline fermentation which
ordinarily occurs in this fluid during warm weath-
er, within a few hours after its escape from the
bladder. It must be remembered, however, that
decomposition of urea into carbonate of ammonia
is also effected by heat, and that, consequently,
the composition and reaction of this fluid is
changed by boiling. For this reason its sterili-
zation by heat is objectionable for certain experi-
ments, and it will be necessary to obtain it from
the bladder free from bacterial contamination, by
the expedient above mentioned (method of Lis-
ter), or by means of a sterilized catheter attached
to a germ-proof receptacle, as recommended by
Pasteur.
Aqueous humor, obtained from the eye of one of
the lower animals, recently dead, is a sterile albu-
166 TECHNOLOGY OF BACTERIA.
minous fluid which has been utilized, especially by
the earlier investigators, as a culture-medium. The
method of operation has commonly been to place
a drop of this fluid, obtained from the eye through
a sterilized canula, upon a perfectly clean cover-
glass, and to invert this over a shallow glass cell
the margin of which has been wet with olive oil,
or with a liquid cement of some kind. This
serves to attach the cover and to exclude atmos-
pheric organisms. The drop of fluid is inoculated
by means of a needle, the point of which has been
dipped into the stock-solution containing the par-
ticular organism which it is proposed to culti-
vate.
This method is especially useful when the de-
velopment of an organism is to be studied by
continuous observation ; for the slide supporting a
culture-cell made in this way may be placed upon
the stage of the microscope, and bacteria in the
drop of fluid may be observed with high powers
through the thin glass cover. This method does
not, however, offer as perfect security as regards
the exclusion of extraneous organisms as is desira-
ble, and it has generally been abandoned for the
methods to be described later, in which a consid-
erable quantity of fluid, enclosed in a germ-proof
receptacle, is used. In this case a microscopical
examination of .the contained organisms requires
that a small portion of the culture-fluid be with-
drawn from the culture-flask, and continuous ob-
servation would be impracticable.
METHODS OF CULTIVATION. 167
Artificial Culture- Fluids. — The culture -fluids
which have been most extensively used in in-
vestigations relating to the physiology and life-
histories of the various species of bacteria are
infusions of animal and vegetable substances, such
as beef, mutton, chicken, fish, gelatine, turnip,
potato, cucumber, hay, malt, etc., etc. These in-
fusions, as a rule, do not require to be very con-
centrated, and they should be as transparent as
possible, as the slightest opacity from suspended
particles, albuminoid or inorganic, may interfere
with the detection by the naked eye of changes
in the fluid due to the development of bacteria,
and with the recognition of these organisms upon
microscopical examination. It sometimes occurs
that an infusion of beef or of chicken, which has
been carefully filtered and is quite transparent,
becomes opalescent from the coagulation of a
minute quantity of albuminoid material as the
result of the operation of sterilization. I have
found this opalescence difficult to remove by fil-
tration. It is objectionable, but could hardly be
mistaken for the opalescence, or milky opacity,
which results from the breaking-down of an infu-
sion of this kind, and with due care the experi-
menter is not likely to be deceived, especially if
he retains a portion of the sterilized fluid for
comparison with that used in his culture experi-
ments.
Nitrogen, which is an essential element of the
protoplasm of bacterial organisms, is supplied by
168 TECHNOLOGY OF BACTERIA.
the albumen of animal or vegetable origin which
remains in solution in the above-mentioned cul-
ture-media. But this element can also be appro-
priated when present in the form of ammonia, or
of one of the salts of ammonia in combination
with a vegetable acid.
Culture -fluids may therefore be made which are
suitable for the development of numerous species
of bacteria, by adding to distilled water a small
quantity of a salt of ammonia, together with cer-
tain mineral salts, as in the formula of Mayer,
given on page 113. Pasteur's solution contains
ten per cent, of sugar candy and a fraction of one
per cent, of ashes of yeast. (See p. 112.)
Sterilization of Culture-Fluids. — Heat is the agent
most available for the sterilization of culture-fluids,
as chemical reagents which would accomplish the
same result would also, by their presence in the
fluid, prevent the development of organisms intro-
duced for the purpose of cultivation. It would
doubtless be possible to sterilize a fluid by means
of a chemical reagent — a mineral acid for exam-
ple— and subsequently to neutralize the germicide
agent — e. g. by lime or magnesia. But in prac-
tice it will be found that no other method is likely
to give as satisfactory results as that commonly
employed ; which consists in subjecting the fluid,
enclosed in a germ-proof receptacle, to a tempera-
ture which insures the destruction of the vitality
of contained organisms.
METHODS OF CULTIVATION. 169
The earlier experimenters assumed that a boiling
temperature must be fatal to the minute organisms
developed in organic infusions; and this false as-
sumption furnished a foundation for the belief,
entertained by some of them, that bacteria might
appear in such fluids by heterogenesis. The as-
sumption has been proved to be false by the
experiments of Pasteur, of Tyndall and of many
others, and it is now known that the reproductive
spores, of endogenous formation, which are devel-
oped in certain species, may resist a temperature
considerably above the boiling-point of water.
(See p. 119.) The writer, while conducting a se-
ries of experiments in the biological laboratory of
Johns Hopkins University, during the summer
of 1881, was greatly troubled by the fact that the
laboratory was infected by the spores of a species
of bacillus, which developed in little islands on the
surface of his culture-fluids, even when they had
been boiled for an hour or more. To destroy the
spores of this bacillus, it was necessary to resort to
the use of a bath of paraffine, or of concentrated
salt-solution, by means of which a temperature of
105° C. was secured. This temperature, main-
tained for half an hour to an hour, proved effec-
tual in the destruction of these ubiquitous spores.
Prolonged boiling will doubtless destroy the vi-
tality of the most refractory spores ; but the exact
time which is required to secure success in every
case has not been determined. In practice, it will
be found best to keep on the safe side, as the loss
170 TECHNOLOGY OF BACTERIA.
of time and material which results from imperfect
sterilization is annoying, and mistakes may arise
from a false confidence in the success of the opera-
tion. To avoid these, it is always best to test
culture-fluids in the culture-oven for several
days before using them for any experiment.
The maintenance of a boiling temperature at
intervals for a day or two is more effectual than
the same amount of continuous boiling. Pasteur
has shown that an alkaline fluid is more difficult to
sterilize than one having an acid reaction. The
vitality of bacteria in active growth is destroyed
by a comparatively low temperature. Thus Chau-
veau has recently made the statement (C. E. Ac.
des Sc., t. XCIV. p. 1694), that the anthrax bacil-
lus is killed (in blood) by exposure for nine or ten
minutes to a temperature of 54° (129.2° Fahr.).
According to Fnsch, B. termo is killed by a tem-
perature of 45° to 50° (113° to 122° Fahr.) — time
of exposure not given. The writer has fixed the
thermal death-point of the micrococcus of induced
septicaemia in the rabbit at 60° (140° Fahr.), the
time of exposure being ten minutes; that of Mi-
crococcus ureae was found to be the same.
The method adopted by Koch for the ^teriliza-
tion of blood-serum for his experiments with the tu-
bercle bacillus has already been mentioned (p. 163).
This method depends for success upon the fact that
the temperature employed, 58°, is sufficient to de-
stroy growing bacteria, and that in the intervals
between the daily heating for one hour the spores
METHODS OF CULTIVATION. 171
have an opportunity to germinate, and are killed
by the subsequent heating. The writer has not
been successful in sterilizing milk by this method,
and has recently lost the greater portion of a batch
of tubes containing blood-serum, carefully treated
according to Koch's directions, from the develop-
ment of Penicillium glaiicum upon the surface of the
jellified serum. The spores of this fungus were
evidently very abundant in the laboratory at the
• time the serum was introduced into these tubes,
which had been well sterilized by heat and were
thoroughly protected by cotton wadding tied over
the mouth of each, with the additional precaution
of covering this with a piece of sheet-caoutchouc
secured by a rubber band. No doubt the unusual
abundance of the spores of Penicillium was due to
the disturbance of the dust upon a lot of books
which were taken down from an upper shelf by
my assistants, shortly before the blood-serum was
decanted and introduced into the culture- tubes.
According to Pasteur, the spores of Penicillium
and other common mucedines are not destroyed
by a temperature of 120 to 125° C (248-257° F.),
in tlie absence of moisture.
Culture Tubes and Flasks. — Glass tubes or flasks
are iised as germ-proof receptacles for the steril-
ized culture-fluids mentioned. Ordinary test-tubes
are commonly employed, and are useful for many
purposes. They should be thoroughly heated in
an oven, or in the flame of an alcohol lamp, just
172 TECHNOLOGY OF BACTERIA.
before the fluid is introduced, to destroy all germs
adhering to their inner surface. The culture-fluid
may be sterilized before or after its introduction
into these tubes. In the former case, the opera-
tion must be performed expeditiously, in as pure
an atmosphere as possible ; and the mouth of the
tube is to be closed at once with a plug of cotton-
wool. It is evident that this method admits of the
entrance of floating atmospheric germs while the
tubes are being filled, and, therefore, that a certain
proportion are likely to break down. The per-
centage of failures will depend upon the skill of
the operator and upon the purity of the atmos-
phere in which the operation is performed. The
liability to failure from contamination by floating
germs is not, however, as great as is commonly
imagined; and experience proves that contact with
instruments or surfaces — e. g. the lip of the vessel
from which the culture-fluid is poured — which are
not perfectly pure, is a more frequent cause of the
breaking-down of the culture-fluid.
Sterilization of the culture-fluid after its intro-
duction into the tubes, offers greater security, and
the following method of manipulation is recom-
mended : Test-tubes, or wide-mouthed bottles
having a capacity of half an ounce or more, are
washed clean, and the mouth of each is covered
with several layers of cotton-wadding. This is
secured in position by means of a strong linen
thread, or a piece of copper wire, tied about the
neck. The wide-mouthed bottles have the advan-
METHODS OF CULTIVATION. 173
tage of being less fragile, and of standing without
support. They are especially useful for receiving
a solid culture-medium, such as gelatine solution
or jellified blood-serum, as the surface exposed is
greater than when test-tubes are employed. The
only disadvantage attending the use of bottles is
their liability to break when heated in a water-
bath ; but this will not happen when Koch's meth-
od of sterilization at a low temperature.(140° Fahr.)
is employed. The tubes, or wide-mouthed bottles,
are next placed in an oven and subjected for an
hour or more to as high a temperature as the cot-
ton caps will bear without being scorched — about
300° Fahr. They are then cooled, and the culture-
fluid is introduced, without removing the protec-
tive cotton-cap, through a little funnel having a
long and sharp-pointed neck, which is pushed
through the layers of cotton-wadding, either di-
rectly or after making a small orifice with a sharp-
pointed instrument. Usually but one or two
drachms of fluid will be required in each tube.
This must be sterilized by heat, after its introduc-
tion to the culture- tube, unless it is introduced
directly from a germ-proof flask with a slender
neck, such as the writer recommends for the pres-
ervation of culture-fluids in bulk (Fig. 5, p. 177).
In this case, the slender neck of the flask is passed
through the flame of an alcohol lamp, to destroy
germs which may have settled upon its outer sur-
face ; and the hermetically sealed extremity is
broken off with forceps which have also been
174
TECHNOLOGY OF BACTERIA.
recently heated. The flask is then inverted, and
the capillary neck is passed through the opening
in the protective cap of a culture-tube. A suf-
ficient quantity of fluid is then transferred by the
application of gentle heat to the base of the in-
verted flask. (See Fig. 2.) Care must be taken
not to wet the protective cotton with
the culture-fluid ; and immediately
. after this has been introduced, the ori-
fice in the cotton wadding is closed
by placing two more layers of the
same material over those which had
previously been secured to the neck
of the bottle or tube. This outer
protective layer may be conveniently
secured in position by means of a
rubber band which admits of its be-
ing quickly removed for the purpose
Fig- 2> of introducing the bacteria which it
is proposed to cultivate, or of extracting a drop of
fluid for microscopical examination. This is ac-
complished by means of a capillary tube which has
been sterilized by heat just before it is used, and
which is introduced through the small opening in
the inner layers of the cotton cap. When tubes
or bottles prepared in this way are set aside for a
considerable time, or when the free admission of
oxygen to the interior is not considered necessary,
it is well to cover the cotton cap with a piece of
thin sheet-caoutchouc, secured by means of a rub-
ber band. This serves to protect the cotton cap
METHODS OF CULTIVATION. 175
from dust, and the contained fluid is less liable to
contamination when the outer layer of cotton-
wadding is removed for any purpose. It is well
to carbolize the cotton-wadding used for the outer
protective cap, as recommended by Lister. This is
done by soaking it in a solution of one part of crys-
tallized carbolic acid in one hundred parts of anhy-
drous ether, after which it is allowed to dry.
Lister has shown that organic infusions may be
kept indefinitely, without undergoing change, in a
wine-glass covered first with a watch-glass, and
then with a glass shade as shown in Fig. 3. The
apparatus, as arranged in the figure, is purified by
being introduced into a hot oven ; and after it has
cooled, the sterilized fluid is introduced from a
large, double-necked stock-bottle, seen in Fig. 4.
To do this, the cotton cap is removed from the
nozzle of the stock-bottle, and the half of a rubber
ball, having an opening in the centre, is attached to
its extremity. This rubber hemisphere, which has
been previously sterilized by soaking it in a strong
solution of carbolic acid, serves the purpose of
covering the mouth of the wine-glass when the
glass cover — watch-glass — is removed.
Culture-Flasks used ly the Author. — The writer
described, in a paper read at the meeting of the
American Association for the Advancement of
Science, in August, 1881, a method of conducting
culture-experiments which he has found extremely
satisfactory, and which has the advantage of as-
176
TECHNOLOGY OF BACTERIA.
Fig. 3.
a, wine-glass ; b, glass cover
(watch-glass) ; c, bell-glass, sup-
ported by a square glass plate.
suring the greatest possible security from contam-
ination by atmospheric germs.
The culture-flasks employed
contain from one to four fluid
drachms. " They are made
from glass-tubing of three or
four tenths inch diameter, and
those which the writer has
used in his numerous experi-
ments have all been home-
made. It is easier to make
new flasks than to clean old ones, and they are
thrown away after being once used. Bellows, op-
erated by the foot, and a flame of considerable size
— gas is preferable — will be required by one who
proposes to construct these little flasks for himself.
After a little practice, they are rapidly made ; but
as a large number are re-
quired, the time and labor
expended in their prepara-
tion is no slight matter. . . .
After blowing a bulb at the
extremity of a long glass
tube, of the diameter men-
tioned, this is provided with
a slender neck, drawn out
in the flame, and the end of
Flg 4- this is hermetically sealed.
(See Fig. 5.) Thus one little flask after another
is made from the same piece of tubing, until this
becomes too short for further use.
METHODS OF CULTIVATION. 177
" To introduce a culture-liquid into one of these
little flasks, heat the bulb slightly, break off the
sealed extremity of the tube and plunge
it beneath the surface of the liquid (see
Fig. 6). The quantity which enters will
of course depend upon the heat em-
ployed, and the consequent rarefaction
of the enclosed air. Ordinarily the bulb
is filled to about one third of its capacity
with the culture-liquid, leaving it two
thirds full of air, for the use of the micro-
scopic plants which are to be cultivated
in it.
" It is best not to trust to the sterilization of the
culture-liquid previously to its introduction into
the flasks ; for, however great the precautions
taken, many failures would be sure to occur, as
the result of contammation by atmospheric germs
during the time occupied in the manipulations.
Sterilization is therefore ef-
fected by heat after the fluid
has been introduced and the
neck of the flask hermetically
sealed in the flame of an alco-
hol lamp.
" This may be accomplished
by boiling for an hour in a
bath of paraffine or of concen-
trated salt solution, by which ng.8.
a temperature considerably above that of boiling
water is secured. The writer is in the habit of
12
178 TECHNOLOGY OF BACTERIA.
preparing a considerable number of these flasks at
one time, and leaving them, in a suitable vessel
filled with water, for twenty-four hours or longer
upon the kitchen stove. Here the water-bath is
kept boiling at intervals, and the contents of the
flasks can scarcely fail of being subjected to a tem-
perature of 212° Fahr. for eight or ten hours.
When the time is less than this, failures in sterili-
zation are likely to occur, and it is always best to
keep on the safe side. The flasks are next placed
in a culture-oven for two or three days, at a tem-
perature of 35 to 38° (95 to 100° Fahr.), to test
the success of the previous operation, — steriliza-
tion. If at the end of this time the contents re-
main transparent, and no film — mycoderma — has
formed upon the surface of the liquid, the flasks
may be put aside for future use, and can be pre-
served indefinitely.
" To inoculate the liquid contained in one of
these little flasks with organisms from any source,
the end of the tube is first heated, to destroy germs
attached to the exterior ; the extremity is then
broken off with sterilized — by heat — forceps ;
the bulb is very gently heated so as to force out
a little air ; and the open extremity is plunged
into the liquid containing the organism to be cul-
tivated. The smallest quantity of this is suffi-
cient, and as soon as the inoculation is effected,
the end of the tube is again sealed in the flame
of an alcohol lamp. A little experience will en-
able the operator to inoculate one tube from an-
METHODS OF CULTIVATION. 179
other; to introduce a minute quantity of blood
containing organisms directly from the veins of a
living animal; to withdraw a small quantity of
fluid from the flask for microscopical examination,
etc., without any danger of contamination by at-
mospheric germs." 1
A larger flask than those above described, hav-
ing its neck drawn out in the same way, will be
found the most satisfactory receptacle in which
to preserve a quantity of stock solution from
which to fill the smaller flasks as required. It is
well not to attempt to preserve too great a quan-
tity of the various organic infusions used in ex-
perimental work of this kind, in a single flask;
as there is greater danger of the breaking down,
and consequent loss, of the stock, when a ves-
sel is frequently opened for the purpose of
withdrawing a portion of its contents. It is best
therefore to use a number of flasks of moderate
size, rather than a single large one. There is
always a saving of time and labor, when extensive
experiments are contemplated, in preparing a
considerable quantity of the various culture-fluids
at one time, so that there may be a sufficient
stock on hand in the laboratory to enable the
experimenter to proceed without delay with any
series of experiments he may have in view. The
writer keeps constantly on hand a supply of the
little flasks already described, charged with ster-
1 Extract from a paper by the Author on " The Germicide Value of
certain Therapeutic Agents." The American Journal of the Medical
Sciences, No. CLXX., n. a., pp. 321-343.
180 TECHNOLOGY OF BACTERIA.
ilized urine, beef- tea, chicken bouillon, hay infusion,
Colm's fluid, etc., and would recommend others who
may be inclined to pursue experimental investiga-
tions relating to the bacteria to provide them-
selves in the same way. For a reserved supply
of these and other culture-fluids, flasks containing
from two to four fluid ounces will be found of a
convenient size. The necks of these flasks are to
be drawn out in a powerful flame, so as to form
a slender tube the extremity of which can be
easily fused in the flame of an alcohol lamp, and
which is long enough to permit of its being
broken off at the end and resealed several times.
The fluid is introduced into these flasks exactly
as directed for the smaller ones, viz., by apply-
ing heat to the body of the flask, so as to rarefy
the enclosed air, and plunging the extremity of
the slender neck of the flask, inverted, beneath
the surface of the fluid contained in a suitable
vessel. These flasks are to be hermetically sealed
and sterilized exactly as was directed for the
smaller ones. Each flask should have attached
to it a label showing the character of its contents
and the date of sterilization.
Culture- Oven. — As culture experiments are com-
monly conducted at a constant temperature, it is
necessary to have a receptacle for the culture-
tubes and flasks which can be heated artificially
to any desired point, the temperature being regu-
lated by a thermostat.
METHODS OF CULTIVATION. 181
A rectangular copper vessel, having double
walls to contain water, enclosing an air-chamber,
will be found most suitable for this purpose. When
the space between the double walls is filled, the
air-chamber is surrounded with water on all sides,
except that through which access to it is ob-
tained. This side is closed by a swinging or
sliding door. If the oven is of considerable size,
it is well to have one or more adjustable shelves
in the interior, upon which tubes and flasks may
be placed, as well as upon the floor. A suitable
aperture at the top admits the thermostat to the
water-bath, and another aperture serves for the
introduction of more water when required. A
third aperture, through the centre of the upper
side of the oven, leads to the air-chamber, and ad-
mits of the introduction of a thermometer, the in-
dex of which can be read outside while the bulb is
inside of the oven. In a well-equipped laboratory
several of these culture-ovens will be required, as
experiments conducted at different temperatures
will often be under way at the same time.
The most convenient way of heating an oven
of this kind is by the use of gas and of a Bunsen
or other burner, which insures the complete com-
bustion of the carbon. When gas is used, the
thermostat described below, well known in chemi-
cal laboratories, may be employed.
Thermostat for Gas (Fig. 7). — The elongated
glass bulb a contains a certain quantity of mer-
182
TECHNOLOGY OF BACTERIA.
cury below, and air above. When the air is ex-
panded by heat, the mercury rises through the
tube c, which passes
through the perforated
cork d, and flows into the
space above this cork.
The tube e is connected
by a piece of rubber tub-
ing with a gas-jet, and
the gas continues to pass
through the tube f to the
Bunsen burner, unless
arrested by the rising of
the mercury, which acts
as a valve to close the
lower extremity of the
tube e. This tube is ad-
justable through the cork
j, and it is evident that
the temperature at which
Fi«- 7- the gas supply is shut off
will depend upon the position of its lower extrem-
ity. A minute aperture in the side of the tube
e permits a small quantity of gasx to flow to the
burner, so that the flame may not be entirely ex-
tinguished when the extremity of this tube is
closed by the rising of the mercury. There is dan-
ger, however, when but a small amount of gas is
admitted to a Bunsen burner that the flame may
be extinguished by currents of air. It will there-
fore be found best, in practice, to close this aper-
METHODS OF CULTIVATION.
183
ture, and to have a small constant jet of gas at
the side of the burner, in a position to relight the
gas coming through the thermostat to the burner
when the valve is opened by the falling of the
mercury. The gas for this side jet does not pass
through the burner or the thermostat.
When the experimenter is so situated that he
cannot obtain a supply of gas, the problem of
regulating temperature is not
quite so simple; but the result
may be accomplished by the use
of a magneto-electric thermostat
invented by the writer some years
since.
The regulating thermometer,
Fig. 8, may be made as in the
thermostat just described; but,
instead of a tube conveying
gas, the mercury, when it rises
through the tube c to the space
above the cork d, meets at a cer-
tain point — adjustable — the in-
sulated platinum wires e and /,
completing an electric circuit. A
constant battery is required, —
a single cup is sufficient, — and
an electro-magnet, the lever of
which is made, by some simple
contrivance, to cut down the flame of the kero-
sene or alcohol lamp used as a source of heat.
This electro-magnetic regulator may also be
a
Fig. 8.
184 TECHNOLOGY OF BACTERIA.
used with gas, when great accuracy is required,
by employing the valve shown in Fig. 9, which
was invented by the writer
for this purpose several
years since.
The bent tube a is con-
nected with the gas supply
by a piece of rubber tubing.
The upright arm of this tube is enclosed in a larger
tube by having an outlet e, which is connected
with the burner. The upper end of this larger
tube is closed by means of a piece of sheet-rubber,
and when this is depressed by means of the lever c,
the flow of gas through the valve is arrested. The
lever c has attached to it the armature d, and is
operated by an electro-magnet under the control of
the regulating thermometer. To prevent the flame
at the burner from being entirely extinguished
every time the valve is closed, a small aperture o
is made in the upright arm of the bent tube a.
§ 2. THE EECOGNITION OF BACTERIA. — The
breaking down of a culture-fluid, either as the re-
sult of inoculation or of accidental contamination,
may commonly be recognized by the naked eye.
The fluid, previously transparent, may become
opalescent or milky in appearance, from the pres-
ence of a multitude of bacteria distributed through
it ; or we may observe a pellicle upon the surface,
while the fluid below remains transparent ; or,
if some time has elapsed, the micro-organisms,
THE RECOGNITION OF BACTERIA. 185
having exhausted the pabulum necessary for their
development, may have settled to the bottom,
where they form a white pulverulent precipitate,
while the fluid above is transparent. In the lat-
ter case, a milky appearance is produced by shak-
ing the tube so as to distribute the organisms
throughout the fluid.
There is usually no difficulty in recognizing, by
means of the microscope, the minute unicellular
plants to which this change in our culture-fluid is
due. But for this purpose it will often be neces-
sary to use comparatively high powers, — e. g., a
good one- tenth inch objective, — and to resort
to the use of staining reagents. For information
relating to the optical and chemical tests by which
bacteria are to be distinguished from inorganic
substances, and from albuminous or fatty granules,
etc., the reader is referred to Part First of the
present volume, which treats of their morphology,
and especially to the remarks in the second chap-
ter, pages 49-53.
Motile bacteria are at once recognized as living
organisms ; but care must be taken not to mistake
movement due to currents in the fluid, or the
molecular motion — brownien — which minute par-
ticles undergo when suspended in a fluid, for a
vital movement. This is to be distinguished by
the fact that the movements are vibratory, and do
not result in a change in the location or relative
position of the moving particles. Bacteria which
have exactly the same refractive index as the
186 TECHNOLOGY OF BACTERIA.
fluid in which they are immersed, are invisible ;
but if endowed with active movement, they may
be detected by the disturbance they cause among
motionless objects which happen to lie in their
course. Thus the septic vibrio of Pasteur is so
slender and transparent as to be almost invisible ;
but when present in the blood of a septicaemic rab-
bit, its vigorous serpentine movements are marked
by a displacement of the blood globules, which it
moves as a serpent moves the grass in which it is
concealed. This septic vibrio I have found in the
blood of rabbits, victims of my experiments in
New Orleans during the summer of 1880.
The use of staining reagents is indispensable
for the recognition of these extremely transparent
or extremely minute species. Their value has
recently been demonstrated by Koch, in a most
striking manner, by the discovery of a specific
bacillus in the lungs and sputum of patients suf-
fering with pulmonary consumption, which had
escaped the observation of pathologists and mi-
croscopists up to the time of his announcement
of its presence and peculiar color-reaction.
§ 3. STAINING BACTERIA. — By far the most use-
ful staining reagents are the aniline dyes, first rec-
ommended by Weigert. Previously to the intro-
duction of this method, hasmatoxylin had been
used to some extent, but did not give very satis-
factory results, as " it does not stain rod-shaped
bacteria at all, and only colors the spherical so
STAINING BACTERIA. 187
slightly as to prevent their certain recognition
when isolated" (Koch). The aniline colors most
used are the methyl- violet, aniline-brown, fuchsin,
and methyl-blue.
An aqueous solution of methyl-violet is perhaps
the most generally useful staining fluid ; and in
the violet ink sold by the stationers we have a
solution ready made, which answers every pur-
pose. It usually requires to be filtered. The
mode of operating is as follows : The fluid con-
taining the bacteria to be stained is spread in as
thin a layer as possible, and allowed to dry, upon
a thin glass cover. The drying may be hastened
by passing the cover-glass, held in forceps, through
the flame of an alcohol lamp. A drop or two of
the staining-fluid is then poured upon the cover-
glass, and after being left a short time is washed
away by a gentle stream of water, or by agitating
the cover in a glass of clean water. Usually one
or two minutes is sufficient time to ensure the
staining of the bacteria attached to the cover.
For immediate examination, it is now only neces-
sary to place the cover on a glass slide over a
little drop of distilled water. It is better, how-
ever, to support the margin of the cover by means
of a circle of white zinc cement, turned in the
centre of the slide. This prevents the bacteria
from being detached by contact with the slide. If
the object is to make a permanent preparation, a
drop of some preservative fluid is placed in the
shallow cell formed by the circle of cement. A
188 TECHNOLOGY OF BACTERIA.
saturated* solution of acetate of potash, or a weak
solution of carbolic acid (one per cent), or camphor
water, may be used for this purpose. The surplus
fluid is removed with blotting paper, and another
circle of cement is turned about the margin of the
cover to hermetically seal the cell. Permanent
preparations may also be made by mounting in
Canada balsam. In this case, the cover-glass is
allowed to dry after staining, and may be treated
with alcohol and oil of cloves, although this is
usually unnecessary ; and too long an exposure to
the action of these agents is likely to remove the
color from the bacteria.
To demonstrate the presence of bacteria in the
tissues, the following method, devised by Weigert,
is strongly recommended by Koch : —
" The objects for examination are first hardened in
alcohol. The sections made from these are allowed to
lie for a considerable time in a pretty strong watery
solution of methyl- violet. They are then treated with
dilute acetic acid, the water removed by alcohol, cleared
up in oil of cloves, and mounted in Canada balsam. . . .
" This is of course only a general outline of the
method ; for the individual tissues, and more especially
the different forms of bacteria, show so great a variety
of result from such treatment that it would be impos-
sible to lay down rules which would be universal and
which would apply to every case. For many objects
fuchsin is best adapted ; for others the methyl colors
are more suitable. Among these latter there exists
such a difference in the staining power that the sec-
tions must lie in one solution only a few minutes, in
another several hours. . .
STAINING BACTERIA. 189
" The strength of the acetic acid solution is not of
much consequence. The best solution is one contain-
ing only a small percentage of the acid, and it is well
not to allow it to act too long. The other manipula-
tions, such as the removal of water, clearing up, and
mounting, are exactly the same as in the preparation
of other microscopic specimens. One must avoid leav-
ing the sections too long in alcohol or oil of cloves;
otherwise the staining material will be washed out by
these fluids." l
The method above described brings to view the
larger forms of bacteria which may be distributed
through the tissues ; but, according to Koch, the
smaller forms may not be distinguished, although
deeply stained, and require for their demonstra-
tion a special form of illuminating apparatus,
which brings out the " color picture/' while de-
tails of structure are to a great extent lost (L c.
p. 27). The illuminating apparatus of Abbe, made
by Zeiss of Jena, is strongly recommended by the
author quoted, and will doubtless be found an
important aid in difficult investigations of the
nature indicated. For ordinary work, however,
a good achromatic condenser will furnish the
necessary illumination, and it will be found that
a good one-sixth or one-tenth inch objective an-
swers very well for this purpose.
In order to render the number and distribution
of the bacteria in an organ more evident, Koch
1 Traumatic Infective Diseases, English translation, p. 23. London,
1880.
190 TECHNOLOGY OF BACTERIA.
recommends the following method. After stain-
ing with an aniline color, soak the sections in a
weak solution of carbonate of potash, instead of
acetic acid. By this means the animal tissues,
including nuclei and plasma cells, lose their color,
while the bacteria alone remain stained. .
Staining the Tubercle- Bacillus. — The following
method was first recommended by Koch: One
cubic centimetre of a concentrated alcoholic solu-
tion of methyl-blue is added to two hundred
cubic centimetres of distilled water, and well
shaken ; then add, under continuous shaking, two
tenths cubic centimetres of a ten per cent solution
of caustic potash. The cover-glasses upon which
tuberculous sputum has been spread and dried,
or thin sections of a tuberculous lung, etc., are
left in this solution for twenty -four hours. If the
solution is heated in a water-bath at 40° C., the
staining will be effected in much less time, — half
an hour to an hour. The preparation is next
treated with a concentrated aqueous solution of
visuvin, which should be filtered just before it is
used. After one or two minutes this is washed
off with distilled water.
The visuvin solution discharges the blue color
from the cells, nuclei and tissue elements gener-
ally, giving them a brown color, while the tuber-
cle-bacilli retain their blue color and are readily
recognized.
STAINING BACTERIA. 191
Baumgarten' s Method. — In this method the spu-
tum dried upon a cover-glass is moistened with a
very dilute solution of potash, — one or two drops
of a thirty-three per cent solution in a small
watch-glass filled with distilled water. According
to Baumgarten the bacilli may now be seen with
a power of 400 to 500 diameters. The film of
sputum is then allowed to dry, and the cover-
glass is passed two or three times through the flame
of an alcohol lamp, after which it is treated with
an aqueous solution of one of the aniline colors.
Baumgarten asserts that by this treatment the
decomposition bacteria are deeply colored, while
the tubercle-bacilli remain absolutely colorless.
EhrlicJis Method. — This method is considered
by Koch a decided improvement upon his own,
and has been employed with success by numerous
observers in various parts of the world, especially
for the examination of sputum. This is spread
upon a cover-glass in as thin a layer as possible ;
and, in order to fix the albumen, the cover-glass
is passed through the flame of a lamp three or
four times, or kept at a temperature of 100 to
110° C. for an hour. The staining solution is pre-
pared as follows : About five parts of pure aniline
(" aniline oil ") are added to one hundred parts of
distilled water, well shaken, and filtered through
a moistened filter. A saturated alcoholic solution
of fuchsin, methyl-violet, or gentian-violet, is
added to this mixture, drop by drop, until pre-
192 TECHNOLOGY OF7 BACTERIA.
cipitation commences. The cover-glass is allowed
to float upon this mixture, which may be con-
veniently prepared in a watch-glass, for fifteen
minutes to half an hour ; the side upon whicR
the sputum has been spread is, of course, placed
in contact with the staining fluid. The cover is
then washed for a few seconds in a strong solu-
tion of nitric acid (one part of the commercial
acid to two parts of distilled water). After this
it must be thoroughly washed in pure water.
By this process the stain is removed from every-
thing but the tubercle bacilli, which retain the
color imparted to them by the first operation.
The ground-substance may now be stained so as
to give a strong contrast with the bacilli ; brown
if the bacilli are violet, or blue if they have been
stained red with fuchsin.
Gibbs Method. — The following method of stain-
ing the tubercle-bacillus is recommended by Dr.
Gibbs, of King's College, London : —
" The great advantage consists in doing away with
the use of nitric acid. The stain is made as follows :
Take of rosanilin hydrochloride two grammes, methyl
blue one gramme ; 'rub them up in a glass mortar. Then
dissolve aniline oil 3 c. c. in rectified spirit 15 c. c. ; add
the spirit slowly to the stains until all is dissolved, then
slowly add distilled water 15 c. c. ; keep in a stoppered
bottle. To use the stain: The sputum having been
dried on the cover-glass in the usual manner, a few
drops of the stain are poured into a test-tube and
STAGING BACTERIA. 193
warmed ; as soon as steam arises, pour into a watch-
glass, and place* the caver-glass on the stain. Allow it
to remain for four or five minutes, then wash in methy-
lated spirit until no more color comes away; drain thor-
oughly and dry, either in the air or over a spirit-lamp.
Mount in. Canada balsam. The whole process, after the
sputum is dried, need not take more than six or seven
minutes. This process is also valuable for sections of
tissue containing bacilli, as they can be doubly stained
without the least trouble. I have not tried to do this
against time, but have merely placed the sections in the
stain and allowed them to remain for some hours, and
then transferred them to methylated spirit, where they
have been left as long as the color came out. In this
way beautiful specimens have been made, without the
shrinking which always occurs in the nitric acid pro-
cess." — Lancet, May 5, 1883.
Cheyne recommends the Weigert-Ehrlich stain-
ing solution. The formula is : of a filtered watery
solution of aniline one hundred parts, of a satur-
ated alcoholic solution of the basic aniline dye
(methyl-violet, gentian-violet, fuchsin, etc.,) eleven
parts ; mix and filter. Rapid staining is obtained
by warming the solution. The specimens are then
decolorized by immersion in nitric acid (one part
in two of water), and stained in a suitable contrast
color. Very delicate sections are apt to be injured
by immersion in the nitric acid." Tn this case, after
staining them in the Weigert-Ehrlich fuchsin so-
lution, they may be washed in distilled water, im-
mersed in alcohol for a moment, and then placed
in the following contrast stain for one or two
13
194 TECHNOLOGY OF BACTERIA.
hours : distilled water 100 c. c., saturated alcoholic
solution of methyl blue 20 ID. c., formic acid 10
minims.
According to Koch the bacillus of leprosy has
the same color reaction as the tubercle-bacillus,
while all other bacteria known to him differ from
these in that the color imparted by one of the
aniline dyes is discharged by visuvin and by nitric
acid, used as above directed.
The tubercle-bacilli stained by any of the meth-
ods given are likely to fade after a time, especially
when mounted in fluid, e. g., glycerine or water.
§ 4. PHOTOGRAPHING BACTERIA. — Bacteria are
prepared for photography as above directed ; that
is, a thin film of the material containing them is
attached to a cover-glass by drying, stained, and
mounted over a shallow cell containing fluid, or in
balsam. For the larger forms methyl-violet is a
suitable stain for this purpose; but a color less
transparent for the actinic rays, such as aniline-
brown or visuvin, will be required for the smaller
species.
The writer has given an account of the technique
of photo-micrography in another work, to which
the reader desiring fuller information is referred.1
It is but fair to say that satisfactory results can
only be obtained by the expenditure of a consid-
erable amount of time and money, as the work
1 Photo-Micrographs and How to make them. James R. Osgood &
Co., Boston, 1883.
PHOTOGRAPHING BACTERIA. 195
must be done with high powers, and the technical
difficulties to be overcome are by no means incon-
siderable. The illustrations in the present volume
may be taken as fair samples of what may be ac-
complished, and it will be found easier to criticise
these than to improve upon them. Koch says, in
his " Traumatic Infective Diseases " : —
"In a former paper I expressed the wish that ob-
servers would photograph pathogenic bacteria, in order
that representations of tl\em might be as true to nature
as possible. I thus felt bound to photograph the bac-
teria discovered in the animal tissues in traumatic infec-
tive diseases, and I have not spared trouble in the
attempt. The smallest, and in fact the most interesting,
bacteria, however, can only be made visible in animal
tissues by staining them, and by thus gaining the ad-
vantage of color. But in this case the photographer
has to deal with the same difficulties as are experienced
in photographing colored objects, e. g., colored tapestry.
These have, as is well known, been overcome by the
use of colored collodion. This led me to use the same
method for photographing stained bacteria ; and I have
in fact succeeded, by the use of eosin-collodion, and by
shutting off portions of the spectrum by colored glasses,
in obtaining photographs of bacteria which had been
stained with blue and red aniline dyes. Nevertheless,
from the long exposure required and the unavoidable
vibrations of the apparatus, the picture does not have
sharpness of outline sufficient to enable it to be of use
as a substitute for a drawing, or indeed even as evi-
dence of what one sees. For the present, therefore,
I must abstain from publishing photographic repre-
sentations."
196 TECHNOLOGY OF BACTERIA.
The difficulty of obtaining satisfactory photo-
micrographs of the smallest micro-organisms is
illustrated in Figures 3 and 6, Plate XL These
represent the best results which the writer has
been able to attain from a large number of trials
in photographing the tubercle-bacillus. In Fig. 3
there are six of these bacilli, included within an
epitheloid cell, from a specimen of the sputum of
a tuberculous patient. The specimen is well stained
with fuchsin by Ehrlich's method ; and under the
microscope the outlines of the cell, with its nucleus
and the deeply-stained bacilli, are seen very dis-
tinctly. But in the attempt to photograph this
object it was found to be impossible to bring all
of the bacilli into focus at the same time ; so that,
while two bacilli are seen with tolerable distinct-
ness, the others, being a little out of focus, can
scarcely be distinguished. Fig. 6 represents the
best result I have been able to obtain in photo-
graphing a single bacillus from the same source,
stained in the same way, — with fuchsin. A close
inspection will show that this bacillus is formed
of a chain of four oval spores. When it is re-
membered that this is magnified 1,000 diameters,
and has been stained and mounted secundum artem,
it will not appear surprising that this minute ba-
cillus escaped observation for so long a time.1
1 In remodelling the plates for the second edition of this work, the
photo-micrographs above referred to have been omitted, and we give in
place of them a reproduction of some of Koch's beautiful illustrations
(chromo-lithographs, Plate IX.), which will no doubt be found more
satisfactory.
COLLECTION OF BACTERIA. 197
§ 5. COLLECTION OF ATMOSPHERIC BACTERIA. —
Fully developed bacteria are rarely found in the
atmosphere; but we have ample evidence that the
spores, or " germs," of numerous species are con-
stantly present, in association with the reproductive
elements of plants higher in the scale, and espe-
cially of the Mucorini and other microscopic fungi.
Considerable attention has been given to the
study of atmospheric organisms with reference to
the question of their possible connection with the
epidemic prevalence of certain diseases. This is
not a proper place to give a summary of the results
attained ; but the general statement may be made,
that these have not been of a definite character,
and that up to the present time no one has suc-
ceeded in demonstrating, in infected atmospheres,
the presence of any specific forms of bacteria
which were clearly connected with the deleterious
effects produced in man or the lower animals by
the respiration of such atmospheres. This line of
investigation, however, has by no means been ex-
hausted ; and the careful and systematic study of
atmospheric organisms in different localities, at
different seasons, and under various circumstances
as to sanitary conditions, is greatly to be desired.
Any one who may be inclined to enter this field
of investigation will do well to make himself
familiar with what has already been done, and
especially with the work of Maddox and Cunning-
ham of England, and of Miquel of Paris. The
last-named observer has given much time to the
198 TECHNOLOGY OF BACTERIA.
enumeration of atmospheric bacteria. He finds,
as might have been expected, that they are more
abundant during the summer months; and that
they are less numerous immediately after a heavy
rain, which has the effect of purifying the atmos-
phere, by washing out suspended particles.
Kain-water will always be found fertile in germs ;
and it is evident that when collected with care it
represents the bacterial flora of the atmosphere at
the time of its fall. We may therefore study this
by means of culture-experiments, in which a variety
of sterilized organic infusions are inoculated with
one or more drops of rain-water which has just
fallen. It is necessary to use many different
culture-fluids, because various organisms require
special media for their development.
Again, we may expose our sterilized organic in-
fusions to the air, and thus permit them to become
fertilized by the deposition of air-borne germs, the
development of which is subsequently studied as
they germinate upon the surface, or in the interior,
of these infusions.
Solid culture-media are especially useful for this
mode of investigation, and we may employ organic
infusions to which three to five per cent of gelatine
has been added, as recommended by Koch ; and
also a variety of cooked alimentary substances,
such as moist bread, slices of boiled potato, turnip,
onion, etc., various fruits (cooked or uncooked),
meats of different kinds, etc. Upon the surface
of these, if they are kept moist, and are placed in
COLLECTION OF ATMOSPHERIC BACTERIA. 199
a culture -oven, maintained at a suitable tempera-
ture, little colonies of various organisms will form
from the germination of spores deposited from the
atmosphere. These will soon be recognized by the
naked eye, and different species may often be dis-
tinguished by peculiarities as to growth, color, etc.
It must be remembered that the microbes found
in the atmosphere, so far as we now know, are
accidentally present, and have originated else-
where; i. e.y in decomposing material of organic
origin from the surface of the earth. But, while
we have no evidence that any known species finds
the pabulum necessary for its development in the
atmosphere, yet there is nothing improbable in
the supposition that this may be true, and that
there are species of bacteria which find in the at-
mosphere all of the conditions necessary for their
rapid multiplication. We know that plants much
higher in the scale, which are merely attached to
others for support, — epiphytes, — derive their sus-
tenance directly from the atmosphere ; and it is
easy to believe that, under exceptional circum-
stances as to the presence of organic matter and
moisture, especially in tropical climates, or during
the summer months in more northern latitudes,
some of these minute microscopic plants may also
multiply abundantly while suspended in the atmos-
phere.
To judge of the relative abundance of special
forms of bacteria in the atmosphere, it will be
necessary to resort to direct microscopic examina-
200 TECHNOLOGY OF BACTERIA.
tion of the dust deposited upon exposed surfaces,
or of the suspended particles collected by means
of an aeroscope.
Various forms of aeroscope have been devised,
the object of all being to cause a current of air to
pass through a small aperture against a glass slide,
the centre of which has been smeared with glycer-
ine or some other viscid material, which serves to
retain suspended particles. In the apparatus of
Maddox, which was used by Cunningham in India,
and a modification of which is employed by Miquel,
a metal cone is made to face the wind by means
of a weather-vane to which it is attached. A small
aperture at the apex of the cone permits the con-
centrated current of air to project itself against
a glass slide, smeared with glycerine, which is
properly supported at a short distance back of this
orifice. In the apparatus used by Klebs and
Tomasi-Crudeli, in their investigations in the vicin-
ity of Rome, a current of air is produced by a
revolving " fan-wheel " moved by clock-work. The
writer, in his investigations in Havana in 1879,
and in New Orleans in 1880, used a water-aspirator,
by means of which a measured quantity of air was
caused to flow in a given time, through a small
aperture, and to impinge upon a glass slide smeared
with glycerine. Any one of these methods will
answer the purpose ; but the apparatus of Maddox
seems to be the simplest, and has yielded very
satisfactory results.
Instead of collecting the suspended organisms
ATTENUATION OF VIRUS. 201
by means of a drop of glycerine attached to a
glass slide, Pasteur has proposed to collect them
by passing a current of air through a glass tube
containing a loosely-packed filter of gun-cotton.
This is subsequently dissolved in ether, and, upon
evaporation of the ether, the particulate atmos-
pheric impurities are found in the film of collodion
remaining.
Examination of Water. — The bacterial flora of
water from any source may be studied by the
method already referred to in speaking of rain-
water ; viz., by using a small quantity to inoculate
a variety of sterilized organic infusions, and ob-
serving the development of the various micro-
organisms which make their appearance as the
result of this procedure.
Dr. Angus Smith of Manchester has recently
given a favorable account of results obtained by
the gelatine method proposed by Koch. Pure fish-
gelatine is added to the water to be tested, in
sufficient quantity to form a gelatinous mass. If
the water is pure, this remains for a long time un-
altered ; but, if impure from the presence of living
organisms, the gelatine becomes liquefied in the
vicinity of these, and little bubbles are formed, at
the bottom of which the bacteria will be found.
§ 6. ATTENUATION OF VIRUS. — Various methods
of producing physiological varieties of pathogenic
bacteria, to be used in protective inoculations, have
202 TECHNOLOGY OF BACTERIA.
been proposed since Pasteur first announced (1880)
that the microbe of fowl-cholera could be modified,
by special treatment, in such a manner that it no
longer produced a fatal form of the disease ; and
that fowls inoculated with this " attenuated virus "
were subsequently protected against the disease,
resisting inoculation with the most potent virus.
Method of Pasteur. — Pasteur found that the
poison of fowl-cholera was most virulent when ob-
tained from fowls which had died from a chronic
form of the disease, and that this virus could be
cultivated in chicken-bouillon for many successive
generations without any diminution of its potency,
if the interval between two successive inoculations
was not greater than two months. But when a
greater interval than this was allowed to elapse,
the disease produced by inoculation was of a less
serious character, and fewer deaths occurred. This
diminution of virulence became more marked in
proportion to the length of time during which a
culture-solution containing the microbe remained
exposed to the action of the atmosphere, and at
last all virulence was lost, as a result of the death
of the parasite. That this result is due to contact
with the oxygen of the air is shown by the fact
that virus enclosed in sealed tubes does not undergo
this modification, but retains its full virulence for
many months. According to Pasteur, the various
degrees of modification of virulence produced by
prolonged exposure to oxygen are preserved by
ATTENUATION OF VIRUS. 203
the cultivation, at short intervals, of the different
grades of " attenuated virus."
Subsequent experiments with the virus of an-
thrax (charbon) gave similar results ; and, under the
direction of Pasjieur, extensive protective inocula-
tions have been practised in France with attenu-
ated virus prepared by this method.
The time of exposure to oxygen is less for the
anthrax bacillus than is required in the case of the
micrococcus of fowl-cholera ; and it is necessary
to cultivate the bacillus in such a way as to pre-
vent the development of spores, as these retain
their virulence unchanged for many years. This
is accomplished by cultivating the bacillus at a
temperature of 42° to 43° C., at which point no
spores are developed, the organism multiplying by
fission only. Contact with the atmosphere for a
month destroys entirely the vitality of the bacillus
in such a culture, and in eight days it loses its
deadly properties, — the temperature being main-
tained at the point mentioned. During this time
the virus passes through successive degrees of at-
tenuation. It is possible to restore the mitigated
virus to its full activity by inoculating a guinea-
pig one day old^ which is killed by the operation,
and using the blood of this animal to inoculate a
second ; and so on. After repeating this operation
several times, the poison is said by Pasteur to re-
gain its full vigor, and to be fatal to a sheep. In
the same way the attenuated virus of fowl-cholera
may be restored to full vigor by inoculating a
204 TECHNOLOGY OF BACTERIA.
small bird, — sparrow or canary, — to which it is
fatal. After several successive inoculations from
bird to bird, the virus resumes its original activity.
Method of Toussaint. — The effect produced upon
pathogenic organisms by prolonged exposure to
oxygen, Toussaint proposes to produce more ex-
peditiously, by subjecting them for a short time to
a temperature a little less than is required for the
complete destruction of vitality.
According to Chauveau, this is best accomplished,
in the case of Bacillus anthrads, by exposure for
eighteen minutes to a temperature of 50° C. Ex-
posure to this temperature for twenty minutes is
said to kill the bacillus ; while " heating for eighteen
minutes produces an excellent attenuated virus for
vaccination."
A first vaccination with feeble virus (heated to
50° for fifteen minutes), and a second inoculation,
at the end of fifteen days, with a strong virus (blood
heated to 50° for nine or ten minutes), preserves
sheep from the effects of subsequent inoculations
with virus of full strength. The heating must be
in small tubes, not more than 1 mm. in diameter ;
and at the end of the time fixed these must be
quickly withdrawn from the hot bath and plunged
into cold water.
The blood of a guinea-pig which has just died
from anthrax, at the end of thirty-six to forty-eight
hours from the time of inoculation, is said to be a
good active virus upon which to operate by this
ATTENUATION OF VIKUS. 205
method. The attenuated virus, when used to in-
oculate a culture-fluid, develops more or less
rapidly, according to the degree of attenuation.
Bacilli heated for the longest time, and those sub-
jected to the highest temperature, are the longest
in showing signs of development.
MetJwd of CJiauveau. — Chauveau has attempted
to test experimentally the question whether sus-
ceptible animals might not resist infection by a
small number of active bacilli, and acquire im-
munity as the result of such inoculation. His
results were favorable to the view that this is true
as regards anthrax, at least ; and Salmon has since
adduced satisfactory evidence that it also applies
to fowl-cholera. The method adopted by Chau-
veau consisted in diluting infected blood from the
guinea-pig until a cubic centimetre of the mixture
contains, as nearly as can be computed, the num-
ber of bacilli desired. A given quantity of this
fluid was injected into the jugular vein of a sheep.
Sheep of native French breeds were invariably
killed when the number of bacilli introduced into
the circulation was about one thousand. In an
experiment in which two hundred and fifty bacilli
were injected into each of five sheep, all with-
stood the dose, and four showed immunity when
reinoculated at the end of six weeks. Immunity
against symptomatic anthrax was also procured by
the same procedure. Salmon, who has tested this
method in fowl-cholera, has arrived at the follow-
ing conclusions : —
206 TECHNOLOGY OF BACTERIA.
" First. — A single disease-germ cannot produce this
extremely virulent disease ; it cannot even multiply
sufficiently to produce the local irritation at the point
of inoculation. When a quantity of virus was intro-
duced into the tissues, which should have contained at
least twelve germs, there was no effect, either general
or local ; but by increasing this one third, with the same
birds, the local irritation appeared.
" Second. — It is apparent that the local resistance to
the germs fails, while the constitutional resistance may
still be perfect, and that in this case there may be a
local multiplication of the organisms for two or three
weeks without any disturbance of the general health.
" Third. — That this local multiplication of the virus
is sufficient to grant a very complete immunity from the
effects of such virus in the future." 1
Method by Intravenous Injection. — In sympto-
matic anthrax, it has been found by Arloing,
Cornevin, and Thomas, that intravenous injection
of the virus produces in the calf, the sheep, and the
goat only a slight indisposition, lasting for two or
three days; and that subsequently the tumors
characteristic of this disease are not developed as
the result of inoculation in the muscles with the
bacterium to which the disease is ascribed.
Attenuation of Virus ly Chemical Reagents. — The
attenuation of virulence which results from ex-
posure to oxygen (method of Pasteur), or to an
elevated temperature (method of Toussaint), seems
to depend upon diminished reproductive activity
i The Med. Record, April 7, 1833, p. 371.
ATTENUATION OF VIRUS. 207
of the pathogenic organism. Evidently the tis-
sues of a susceptible animal are able to resist the
invasion of a limited number of active germs (di-
lution of virus), and of a still greater number of
those which are less active as a result of the
treatment referred to.
The writer has obtained evidence, in the course
of his experiments relating to the comparative
value of disinfectants, which goes to show that
certain chemical reagents, also, may modify the
virulence of pathogenic bacteria in a similar man-
ner. In these experiments, the blood of a rabbit
recently dead from induced septicaemia was the
virulent fluid used as a test. The pathogenic or-
ganism in this case is a micrococcus, which is
found in normal human saliva. In the published
report of these experiments the following state-
ment is made : —
" The most important source of error, however, and
one which must be kept in view in future experiments,
is the fact that a protective influence has been shown to
result from the injection of virus, the virulence of which
has been modified, without being entirely destroyed, by
the agent used as a disinfectant." l
Sodium hyposulphite and alcohol were the chem-
ical reagents which produced the result noted in
these experiments ; but it seems probable that a
variety of antiseptic substances will be found to
be equally effective, when used in the proper pro-
1 Studies from the Biological Laboratory, Johns Hopkins University,
Vol. II. No. 2, p. 205.
208 TECHNOLOGY OF BACTERIA.
portion. Subsequent experiments have shown that
neither of these agents is capable of destroying
the vitality of the septic micrococcus in the pro-
portion used (one per cent of sodium hyposulphite
and one part of ninety-five per cent alcohol to
three parts of virus), and that both have a re-
straining influence upon the development of this
organism in culture-fluids.
PAET FOURTH.
GERMICIDES AND ANTISEPTICS.
A KNOWLEDGE of the vital resistance of the
various species of bacteria to the action of differ-
ent chemical reagents is important from several
points of view. First, such information has an
important bearing upon elementary biological
problems, which are best studied in these simple
unicellular plants; second, practical sanitation, and
the preservation of various food-products, depend
to a considerable extent upon the proper use of
germicides and antiseptic's; and, third, modern
therapeutics has been largely influenced by the
indications which this knowledge seems to furnish
for the treatment of infectious diseases and surgi-
cal injuries.
By a germicide agent we mean one which has
the power to destroy the vitality of the various
species of bacteria known to us, including those
disease-germs which have been demonstrated,
such as the anthrax bacillus, the bacterium of
symptomatic anthrax, the micrococcus of fowl-
cholera, that of septicaemia in the rabbit, etc.
H
210 GERMICIDES AND ANTISEPTICS.
Germicides are also antiseptics, as the bacteria of
putrefaction are killed by them as well as those
mentioned. They may also arrest putrefactive
decomposition in quantities less than are required
to completely destroy putrefactive organisms.
But an antiseptic is not necessarily a germicide ;
for experiment proves that certain substances ar-
rest putrefaction which have not the power to kill
the bacteria to which this is due. This they do
by arresting the vital activity — multiplication —
of the germs of putrefaction, or by so changing
the nutritive pabulum required for the develop-
ment of these germs that they are unable to
appropriate it to their use.
If it were proven that the infectious character
of every kind of infective material depended upon
the presence of a specific living germ, as has been
shown to be true in the case of certain kinds of
infective material, germicide and disinfectant would
be synonymous terms. Although this has not
been proved, it is a significant fact that all of the
disinfectants of established value have been shown
by laboratory experiments to be potent germi-
cides.
The antiseptic value of a substance is readily
determined by a series of experiments in which it
is added in various proportions to putrescible or-
ganic substances, and observing if, under favorable
conditions as to temperature and moisture, putre-
faction is arrested or prevented.
Some observers have made arrest of motion in
GERMICIDES AND ANTISEPTICS. - 211
the motile bacteria a test of germicide power.
But it is evident that this is unreliable, and the
only safe test is failure to multiply, under favora-
ble conditions, in a suitable culture-fluid. This
test requires care in its application, as contamina-
tion of the culture-fluid by other organisms than
those which have been subjected to the action of
the germicide agent would give a misleading
result.
The method adopted by the writer in a series of
experiments, the results of which are published in
the " American Journal of the Medical Sciences,"
April, 1883, is very satisfactory and reliable. This
consists in the use of the little culture-flasks, con-
taining a sterilized organic infusion, prepared as
directed on p. 176 of the present volume.
The bacteria which serve as a test are subjected
to the action of the germicide in a small glass
tube, previously sterilized by heat; and, after a
given time, which in the experiments referred to
was two hours, the fluid in the culture-flask is in-
oculated with a minute drop of fluid from the tube
containing the test-organisms. The culture-flask
is then placed in the oven, at a temperature of
98°- 100° Fahr. At the end of twenty-four to
forty-eight hours, inspection of the little flask will
show in a very definite manner whether the ger-
micide has been effectual or not : for the fluid
will remain unchanged and transparent if the test-
organisms were killed by the germicide agent ; or,
in case of failure, will have broken down, and will
212 GERMICIDES AND ANTISEPTICS.
present an opalescent or milky appearance, from
the abundant development which has taken place
as the result of inoculation.
When a pathogenic organism is used to test
the germicide power of chemical substances, we
may inoculate living animals instead of sterilized
culture-fluids. In this case, failure to produce the
characteristic symptoms of the disease is, of course,
to be taken as evidence that the vitality of the
pathogenic germs was destroyed before inocula-
tion. The most available organisms for such ex-
periments, in the present state of science, are the
bacillus of anthrax, the micrococcus of fowl-chol-
era, the bacterium of symptomatic anthrax, and
the micrococcus of induced septicaemia in the
rabbit.
In a series of experiments made by the writer
in 1881, the last-named organism, as found in the
blood of a rabbit recently dead, served as the test.
The results were on the whole quite satisfactory
and definite ; but there are certain sources of error
connected with this method which should be borne
in mind. First. The test-organistn may be modi-
fied as regards reproductive activity without being
killed ; and, in this case, a modified form of dis-
ease may result from the inoculation, of so mild
a character as to escape observation. Second. An
animal which has suffered this modified form of
disease, enjoys protection, more or less perfect,
from future attacks, and if used for a subsequent
experiment may, by its immunity from the effects
GERMICIDES AND ANTISEPTICS. 213
of the pathogenic test-organism, give rise to the
mistaken assumption that this had been destroyed
by the action of the germicide agent to which it
had been subjected.
Vaccine virus has also been used by the writer,
and by other experimenters, to test the compara-
tive value of disinfectants. The method consists
in dividing a certain quantity of virus from the
same source into two parts, and subjecting one
portion to the action of the agent to be tested,
while the other is reserved to prove the reliability
of the material used. A negative result from vac-
cination with the disinfected virus, and a positive
result from that not disinfected, is evidence of the
power of the disinfectant used to destroy the in-
fective virulence of the material. The experiment
must of course be made upon unvaccinated chil-
dren, and it is best to make it in duplicate, two
punctures being made upon one arm with the
disinfected virus, and two in the other with that
not disinfected.
A complete resume of the experiments which
have been made to determine the value of anti-
septics and disinfectants would require more space
than can be given to this subject in the present
volume. Nor can the results obtained by different
methods be brought together in tabular form ; for
discrepancies exist, due to various circumstances,
and an extended discussion would be required to
reconcile these, or to determine which were en-
titled to the greatest consideration. These dis-
214 GERMICIDES AND ANTISEPTICS.
crepancies arise from the following circumstances :
(a) The different bacteria which have been used
as test-organisms differ within certain limits as
regards vital resistance to the action of germicide
agents. A like difference may occur in a particu-
lar species (b) as the result of the presence or
absence of reproductive spores ; (c) because of dif-
ferent conditions relating to the physical character
of the material containing the germs; e.g., solid
or fluid, coagulated masses, etc; (d) from a differ-
ence in the reaction of the media in which they
are contained ; (e) from a difference in the time of
exposure to the action of the reagent.
The list which follows is arranged, for con-
venience, in alphabetical order. The writer has
given his own results the precedence ; and, as his
experiments were made -with special care by a
method which offers the greatest possible security
against error, he believes that they will be found,
in the main, to be trustworthy. The letter S,
enclosed in brackets, will be used to designate
these ; while results obtained from other sources
will be followed by the name of the experimenter
who has reported them.
In the author's experiments, unless otherwise
stated in the text, the time of exposure to the
action of the germicide agent was two hours. The
septic micrococcus, frequently referred to below
as one of the test-organisms employed, is from
the blood of a rabbit recently dead, as the result
of inoculation with human saliva ; and, when
GERMICIDES AND ANTISEPTICS. 215
" septicsemic blood" is spoken of, the blood of a
rabbit which has fallen a victim to this form of
septicaemia is meant. (Consult bibliography for
titles of papers by the writer relating to this form
of induced septicaemia in the rabbit.)
Acetic Acid. — This has the lowest preventive
power in Group II. — the Organic Acids (Dougall).
AlcoJwl ranks low as a germicide, but is not with-
out value as an antiseptic. Exposure to ninety-
five per cent alcohol for forty-eight hours did not
kill the bacteria in broken-down beef- tea (old
stock). The septic micrococcus was destroyed by
two hours' exposure to a twenty-four per cent
solution. The micrococcus of gonorrhoeal pus
required a forty per cent solution (S).
"Pure or camphorated alcohol is largely used
by surgeons in France to wash their instruments,
but is evidently capable of giving only an illusory
safety against morbid germs. . . . When saturated
with camphor, alcohol does not destroy the virus
of symptomatic anthrax" (Arloing, Cornevin, and
Thomas). In the proportion of 1: 1.5, it destroys
the bacteria which cause the acid fermentation of
milk (Molke). 1: 1.18 destroys the bacteria of
broken-down beef-tea, and 1 : 20 prevents the de-
velopment of these bacteria in sterilized beef-
infusion (de la Croix). The micrococcus of pus
multiplies freely in a culture-fluid containing five
per cent of alcohol, but fails to multiply in a so-
lution containing ten per cent. Exposure for half
an hour to alcohol in the proportion of twelve per
216 GERMICIDES AND ANTISEPTICS.
cent did not destroy the virulence of septic blood,
which was injected into a rabbit with a fatal result.
Twice this amount, however, proved effectual (S).
Aluminium Acetate. — The development of bac-
teria in pease-infusion is prevented by 1 : 5,250
(Kiihn). The development of bacteria in un-
boiled beef-infusion was prevented by 1: 6,310;
and the bacteria of broken-down beef-tea were
destroyed by 1: 478, while 1: 584 failed (de la
Croix).
Aluminium Chloride. — " Group III. — Salts of
the Alkaline Earths. Here chloride of aluminium
is highest. . . . Were it not for the extremely
high preventive point (1: 2,000) of this salt in the
hay column, this group would occupy a compara-
tively subordinate position" (Dougall).
Ammonia does not destroy the virus of sympto-
matic anthrax (Arloing, Cornevin, and Thomas) ;
or the spores of the anthrax bacillus (Koch).
Aromatic Products of Decomposition. — Bauman first
showed that phenol is developed in albuminous
fluids during the process of putrefaction ; and Sal-
kowski found, in 1875, that old putrid fluids have
antiseptic properties. Wernich has studied this
subject, and finds that the aromatic products of
decomposition, — skatol, phenyl, propionic acid, in-
dol, kresol, phenyl acetic acid, and phenol, — arrest
putrefaction, when present in organic infusions in
small quantities, in the order named.
Arscnimis Acid. — One per cent destroys spores
of bacilli in ten days (Koch).
GERMICIDES AND ANTISEPTICS. 217
Benzoic Acid. — One part in 2,000 retards the
development of spores (Koch). One part in 1,439
prevents development of bacteria in unboiled meat-
infusion ; 1: 2,010 does not. The bacteria of broken-
down beef-tea are destroyed by 1: 77, while 1:
121 failed (de la Croix). In Group II. — the
Organic Acids — benzoic has the highest prevent-
ive power (Dougall.)
Boric Acid in saturated aqueous solution (four
per cent) failed to destroy the three test-organisms
employed in the writer's experiments. But it pre-
vented the development of the M. of pus in the
proportion of 1 : 200 ; of the M. of septicaemia in
1 : 400, and of B. termo in 1 to 800. This differ-
ence, as regards ability to multiply in the presence
of boric acid, accounts for the fact that micrococci
have been observed to be present in the pus of
wounds treated antiseptically with this substance,
although no evidence of putrefaction could be dis-
covered. A two per cent solution destroyed the
virulence of septicsemic blood ; but, in view of the
fact that twice this amount did not kill the micro-
coccus to which this virulence is due, it is evident
that the result obtained in inoculation experiments
upon rabbits was due to the restraining — anti-
septic— power of the reagent, and can not be
taken as evidence of germicide power (S). The
activity of fresh virus of symptomatic anthrax
was destroyed by boric acid, one in five (twenty per
cent) the time of exposure being forty-eight
hours (Arloing, Cornevin, and Thomas). One part
218 GERMICIDES AND ANTISEPTICS.
in 133 prevented the development of bacteria in
tobacco-infusion, while 1 : 200 failed (Bucholtz).
One part in 58 prevented the development of bac-
teria in a vegetable infusion (peas), while 1 : 81
failed ; 1 : 101 failed to preserve a solution of egg-
albumen (Kiihn). A five per cent solution was
found by Koch to be inert, the test being the
anthrax bacillus.
Bromine. — The spores of bacilli are killed by a
two per cent aqueous solution of bromine. In the
form of vapor this agent is superior, as regards
rapidity of action, to chlorine and iodine (Koch).
Bromine vapor is the most active agent for the
destruction of the virus of symptomatic anthrax
(Arloing, Cornevin, and Thomas). It destroys the
ferment of sour milk (Bacterium lactis) in the pro-
portion of 1 : 348 (Molke). The bacteria of broken-
down beef-tea are destroyed by 1 : 336 ; and the
development of bacteria in unboiled meat-infusion
is prevented by 1 : 5597 (de la Croix).
Camphor does not destroy the infective proper-
ties of vaccine except when it is exposed for at
least a week in an air-chamber saturated with the
volatile oil (Braid wood and Vacher). Alcohol sat-
urated with camphor has no action upon the fresh
virus of symptomatic anthrax (Arloing, Cornevin,
and Thomas). One part to 2,500 retards the de-
velopment of anthrax spores (Koch).
Carbonic Acid. — Of five experimental vaccina-
tions with lymph subjected to this gas, three
succeeded (Braidwood and Vacher).
GERMICIDES AND ANTISEPTICS. 219
Carbonic Oxide. — Vaccine lymph may endure at
least twenty-four hours' exposure to carbonic ox-
ide without losing its specific properties (Braid-
wood and Vacher). This gas has no effect upon
bacteria, which readily develop in it (Hamlet).
Carbolic Arid, in the proportion of one to two
hundred, destroys B. termo and the septic micro-
coccus in active growth, while 1 : 25 failed to de-
stroy the bacteria in broken-down beef- tea (old
stock) ; the micrococcus of pus was destroyed by
1 : 225. The development of all of these organ-
isms was prevented by the presence in a culture-
fluid of 0.2 per cent = 1 : 500 (S). The micro-
coccus of swine plague multiplies abundantly in
urine containing 1 per cent of carbolic acid, while
the micrococcus of fowl-cholera is destroyed by
six hours' exposure to a 1 per cent solution (Sal-
mon). A 2 per cent solution destroys the bacte-
rium of symptomatic anthrax (dried virus), the
time of exposure being forty-eight hours (Ar-
loing, Cornevin, and Thomas). The multiplica-
tion of bacteria in urine is not prevented by
1 : 100 (Haberkorn). In egg-albumen develop-
ment of bacteria is prevented by 1 : 200 (Kiihn).
One part to 502 prevents the development of
bacteria in unboiled meat-infusion; but the bac-
teria in broken-down beef-tea are not destroyed
by a 10 per cent solution (de la Croix). A 5 per
cent solution required two days to arrest the
developing power of the spores of Bacillus anthmris,
while a 1 per cent solution destroyed the bacilli
220 GERMICIDES AND ANTISEPTICS.
themselves in two minutes. A solution of 1 : 850
prevented the multiplication of these bacilli in a
suitable culture-medium. Carbolic acid in solu-
tion, in oil or in alcohol, is without effect upon
the spores of B. anthracis, which germinated after
being immersed 110 days and 70 days, respec-
tively, in a 5 per cent solution in oil and in alco-
hol (Koch). The same author found that car-
bolic acid vapor, at 75° C., for two hours, failed
to destroy anthrax spores. Chemical combina-
tions with other substances were less efficacious
than the pure acid. A 5 per cent solution of zinc
sulpho-carbolate destroyed anthrax spores in five
days ; a 5 per cent solution of sodium phenate, in
ten days, merely reduced their power of develop,
ment, while sodium sulpho-carbolate failed to do
this within the same time.
Chloral Hydrate failed to kill the micrococcus of
pus in the proportion of 10 per cent, but was
successful in the proportion of 20 per cent (S).
Chloroform. — A comparatively brief exposure to
chloroform vapor entirely sterilizes vaccine lymph
(Braid wood and Vacher). Chloroform has no effect
upon the fresh virus of symptomatic anthrax
(Arloing, Cornevin, and Thomas). Chloroform is
inert as regards the destruction of the spores of
the anthrax bacillus (Koch). The development
of bacteria in unboiled beef-infusion is prevented
by 1 : 103 ; but 1 : 1.22 failed to destroy the bac-
teria of broken-down beef-tea (de la Croix).
Chlorine.— Ex-p. No. 37, Jan. 27, 1880.— Four
GERMICIDES AND ANTISEPTICS. 221
children were vaccinated with virus from ivory
points which had been exposed for six hours to an
atmosphere containing one half per cent of chlo-
rine (produced by the action of hydrochloric acid
on the peroxide of manganese, and collected over
warm water) ; also with four points, from the same
lot, not disinfected. Result : Vaccination was un-
successful in every case with the disinfected points,
and successful with those not disinfected (S).
Chlorine destroys the fresh virus of symptomatic
anthrax, but is powerless against that which has
been dried (Arloing, Cornevin, and Thomas).
Chlorine is classed with bromine, iodine, and
corrosive sublimate, as one of the most relia-
ble agents for destroying the spores of anthrax
(Koch). Development of bacteria in unboiled
beef-infusion is prevented by the presence of one
part in 15,606, and the bacteria of broken-down
beef-tea are destroyed by 1 : 1,061 (de la Croix).
Chromic Acid, in the proportion of 1 : 1000. de-
stroys the virulence of septicsemic blood (S). The
development of anthrax spores is prevented by
1 : 5000 ; but chromic acid and its salts are ineffi-
cient for the destruction of these spores (Koch).
Chromic acid was found to have a preventive
power surpassing all others, its average being
1 : 2,200, while that of carbolic acid is only 1 : 226
(Dougall).
Citric Acid, in the proportion of 12 per cent,
proved fatal to the micrococcus of pus, while 10
per cent failed (S).
222 GERMICIDES AND ANTISEPTICS.
Creosote, in the proportion of 1 : 200, is fatal to
the micrococcus of pus (S).
Cupric Sulphate destroys the virulence of septi-
csemic blood in the proportion of 1 : 400 (S). The
activity of dried virus of symptomatic anthrax is
destroyed by a 20 per cent solution — time of
exposure forty-eight hours (Arloing, Cornevin, and
Thomas). The metallic salts, from their showing
the highest average preventive power, form
Group I. Sulphate of copper here has not only
the highest individual average, but its three pre-
ventive points, in the three solutions, are very
much higher than those of any other substance
in the group (Dougall).
Ether does not destroy the spores of bacilli after
thirty days' exposure (Koch). A brief exposure to
the vapor of ether destroys the infective power of
vaccine lymph (Braid wood and Vacher).
Eucalyptol retards the development of the spores
of bacilli in the proportion of 1 : 2,500 (Koch). In
the proportion of 1 : 205, the development of bac-
teria in unboiled meat-infusion is prevented. The
bacteria in broken-down beef-tea are not destroyed
by 1 : 14 (de la Croix).
Ferric Sulphate. — A saturated solution of this
salt did not kill any of the test-organisms, and the
use of this agent as a disinfectant would evidently
be a serious error. It has, however, a decided
value as an antiseptic, having prevented the de-
velopment of all of the test-organisms in the pro-
portion of 1 : 200. Although not fatal to the
GERMICIDES AND ANTISEPTICS. 223
septic micrococcus in the proportion of 16 per
cent, it prevents the development of septicaemia
in the rabbit, after inoculation with septic blood
to which it has been added, in the proportion
of 1 : 400 (S). Exposure to a 20 per cent solution
for forty-eight hours did not destroy the virus
of symptomatic anthrax (Arloing, Cornevin, and
Thomas).
Fcrri Chloridi Tinct. — A 4 per cent solution was
fatal to the two species of Micrococcus^ but failed to
kill B. tcrmo. The micrococci were not destroyed
by a 2 per cent solution (S).
Glycerine, in the proportion of 12.5 per cent,
destroyed the virulence of septicaemic blood, but
failed at 10 per cent (S). Glycerine has no action
upon the fresh virus of symptomatic anthrax
(Arloing, Cornevin, and Thomas) ; and is inert as
regards the spores of bacilli (Koch).
Heat. — The thermal death-point of the micro-
coccus of septicaemia (induced septicaemia in the
rabbit) is 140° Fahr. (60° C.), the time of ex-
posure being ten minutes ; that of the micrococ-
cus of gonorrhoeal pus (believed to be identical
with M. ureae, Cohn), is the same (S). The
micrococcus of fowl-cholera is destroyed by expo-
sure for fifteen minutes to a temperature of 132°
Fahr. (Salmon). Nine or ten minutes' exposure
to a temperature of 54° C. is sufficient to com-
pletely kill the bacilli in anthrax blood (Chau-
veau). Cohn has assigned 55° C. as the highest
point at which bacteria studied by him have lived
and developed. Van Tieghem says that this tern-
224 GERMICIDES AND ANTISEPTICS.
'perature is -fatal to most of these organisms; but
he has studied a bacillus which is able to multiply
and form spores in a culture-fluid at a tempera-
ture as high as 74° C., but which ceased to mul-
tiply at 77°. Miquel had previously reported the
existence, in the water of the Seine, of an im-
mobile filamentous Bacillus, whch supports a tem-
perature of 70° C., and which he has cultivated at
this temperature in a neutral meakinfusion. This
Bacillus was killed by a temperature of 71° to 72°
C. The spores of B. subtilis resist for several hours
a temperature of 100° C. (212° Fahr). The time
required to kill these spores varies according to the
nature of the liquid. In yeast-water, and in hay-
infusion, they can resist a boiling temperature for
five hours ; while in distilled water they are killed
after two or three hours. A temperature of
115° C. kills them very quickly (Chamberland).
Desiccated septic blood does not lose its virulence
at the end of forty days ; or by being heated to
100° for from three to twenty-four hours, and the
contained bacteria are capable of multiplication
after such exposure (Lebeden0).
Hydrochloric Acid, in the proportion of 1 : 200,
destroys the virulence of septicasmic blood (S).
Hydrochloric acid gas destroys the contagion of
vaccine (Braid wood and Vacher). A 2 per cent
solution of muriatic acid kills the spores of the
anthrax bacillus in ten days, while the develop-
ment of these spores is prevented by 1 : 1,700
(Koch).
GERMICIDES AND ANTISEPTICS. 22 5
*
Hydrogen. — Bacteria may develop in an atmos-
phere of hydrogen (Hamlet).
Iodine (in aqueous solution with potassium
iodide) destroys the septic micrococcus in the
proportion of 1 : 1,000 ; the micrococcus of pus
and B. tenno in 1 : 500. It prevents the develop-
ment of these organisms when present in a culture-
solution in the proportion of 1 : 4,000 (S). The
development of bacteria in tobacco-infusion is
prevented by 1 : 5,714 (Bucholz); in boiled beef-
infusion, 1 : 2,010; in unboiled, 1:10,020 (de la
Croix). One part in 1,000 destroys the bacteria
which produce the acid fermentation of milk
(Molke) ; and 1 : 410 the bacteria of broken-down
beef-tea (de la Croix).
Mercuric Bichloride. — All experimenters agree in
placing this in the front rank as a germicide and
antiseptic agent. One part in 40,000 prevents
the development of the septic micrococcus, and
but little less is required in the case of the micro-
coccus of gonorrhoeal pus and of B. termo. To
destroy the vitality of bacteria in broken-down
beef-tea (old stock) required 1 : 10,000, while the
above-mentioned micrococci were killed by 1 : 20,-
000 (S). The activity of the virus of sympto-
matic anthrax (dried virus) is destroyed by 1: 5,000
(Arloing, Cornevin, and Thomas). The bacteria
of broken-down beef-infusion are destroyed by 1 :
6,500, and their development in beef-tea prevented
by 1 : 10,250 (de la Croix). One part in 20,000
prevents the development of bacteria in sterilized
15
226 GERMICIDES 'AND ANTISEPTICS.
tobacco-infusion (Bucholz). One part in 1,000
destroys the spores of Bacillus anthracis in ten
minutes (Koch).
Nitric Acid in the proportion of 1 : 400 destroys
the virulence of septicaemic blood — time of con-
tact, half an hour (S).
Nitrous Acid. — Exp. No. 36, Jan. 22, 1880.-
Three children were vaccinated with ivory points
which had been exposed for six hours to an at-
mosphere containing one per cent of nitrous acid
gas (generated by pouring nitric acid on copper
filings, and collected over mercury). Result: Vac-
cination was unsuccessful in each case, with
disinfected points, and successful with the non-
disinfected points from the same lot (S).
Oil of Mustard, in the proportion of 1 : 33,000,
prevents the development of the spores of bacilli
(Koch.) The development of bacteria in unboiled
beef-tea is prevented by 1 : 3,353 ; and 1 : 40 de-
stroys the vitality of bacteria in broken-down beef-
tea (de la Croix).
Oil of Turpentine destroys the spores of bacilli
in five days, and retards their development in the
proportion of 1 : 75,000 (Koch). Turpentine has
no action upon the virus of symptomatic anthrax
(Arloing, Cornevin, and Thomas).
Osmic Acid, in one per cent solution, destroys
the spores of bacilli in one day (Koch).
Oxalic Acid, in saturated solution, destroyed the
virulence of the fresh virus of symptomatic an-
thrax, but had no effect upon dried virus (Arloing,
Cornevin, and Thomas).
GERMICIDES AND ANTISEPTICS. 227
Ozone impairs, and, if maintained long in con-
tact, destroys the activity of vaccine lymph (Braid-
wood and Vacher). All germs suspended in the
air, capable of developing in solutions of yeast
from beer, are killed by ozone (Chappuis).
Oxygen. — The experiments of Pasteur upon the
attenuation of virus show that long exposure to
the oxygen of the atmosphere reduces the repro-
ductive activity of the micrococcus of fowl-cholera
and of the anthrax bacillus, and that after a time
the vitality of these organisms is destroyed. The
spores of the anthrax bacillus are, however, un-
affected by prolonged exposure. Out of twelve
experimental vaccinations with vaccine exposed to
oxygen (time of .exposure one to seven days), but
one was successful, and in this case there is reason
to believe that the exposure was imperfect (Braid-
wood and Vacher).
Picric Add prevents the development of the
spores of bacilli in the proportion of 1 : 5,000
(Koch). The development of bacteria in beef-
infusion is prevented by 1 : 2,005, and the bacteria
of broken-down beef-tea are destroyed by 1 : 100
(de la Croix).
Potash. — Caustic potash in the proportion of
two per cent was fatal to the micrococcus of sep-
ticaemia in one experiment, and failed in another ;
eight per cent failed to kill the micrococcus of pus,
while ten per cent was successful ; ten per cent
failed to destroy the bacteria in broken-down beef-
tea, and twenty per cent was successful (S). " Caus-
228 GERMICIDES AND ANTISEPTICS.
tic potash has the minimum of preventive power,
— 1 : 10. Such a mixture is highly caustic ; still
it was necessary to use it of such strength as at
1 : 25 vibriones and bacteria were abundant "
(Dougall).
Potassium Arsenite (Fowler's solution of) failed
to destroy the micrococcus of pus in the proportion
of forty per cent. According to Koch, arsenite
of potash prevents the development of anthrax
spores in the proportion of 1 : 10,000.
Potassium Chlorate in the proportion of four per
cent does not destroy the virulence of septicsemic
blood (S). " Chlorate of potassium, so much used
as a gargle in stomatitis, diphtheria, etc., where it
is held to act by destroying certain fungi or germs
of specific poison, has not only no preventive
power, but actually accelerates decomposition "
(Dougall).
Potassium Iodide gave no evidence of germicide
power ; exposure to the action of a saturated solu-
tion did not prevent the development of the bac-
teria of broken-down beef-tea (S).
Potassium Nitrate failed in 4 per cent solution to
destroy the virulence of septicsemic blood (S).
Potassium Permanganate. — A 2 per cent solution
destroys the virulence of septicoemic blood. The
micrococcus of pus is destroyed by 1 : 800 (S). A
5 per .cent solution destroys the fresh virus of
symptomatic anthrax, but has no effect upon the
dried virus (Arloing, Cornevin, and Thomas). One
per cent will not destroy the spores of anthrax.
GERMICIDES AND ANTISEPTICS. 229
but in the proportion of 1 : 3,000 their develop-
ment is retarded (Koch). One part in three hun-
dred prevents the development of bacteria in
unboiled beef-infusion ; and one part in thirty-
five kills the bacteria of broken-down beef-tea (de
la Croix).
Pyrogallic Acid. — A solution of one or two per
cent prevents, for some months, the development
of odors and of microscopic organisms ; a solu-
tion of 2.5 per cent removes the odor from fluids
in a state of putrefaction, and destroys bacteria
(Bovet).
Pyroligneous Acid destroys the spores of the An-
thrax bacillus in two days (Koch).
Quinine. — A 10 per cent solution of sulphate of
quinine has no action upon the bacterium of symp-
tomatic anthrax (Arloing, Cornevin, and Thomas).
One per cent of quinine, dissolved with muriatic acid,
destroys the spores of bacilli after ten days' ex-
posure (Koch). The development of bacteria in
a culture-fluid inoculated with a drop of turbid
fluid from malarial soil is prevented by a solution
of muriate of quinine of 1 : 900. From 1 : 1,000
to 1 : 1,500 non-putrid development begins. In a
gelatine-culture from malarial soil no development
occurred in solutions containing 1 : 1,500 ; non-
putrid development occurred from 1 : 2,000 up to
1 : 3,000 ; and the development was accompanied
by putrefaction when less than 1 : 9,000 was used
(Ceri).
Salicylic Acid. — In the writer's experiments, this
230 GERMICIDES AND ANTISEPTICS.
reagent was dissolved by means of sodium bibo-
rate, which, by itself, in saturated solution, has no
germicide power. A two per cent solution was
found to destroy the micrococcus of pus and B.
termo in active growth ; 4 per cent failed to destroy
the bacteria in broken-down beef-tea (old stock).
In the proportion of 1 : 200, this solution prevented
the development of the micrococcus mentioned ;
in 1 : 800, that of B. termo; and the septic micro-
coccus in 1 : 400. But the antiseptic power exhib-
ited by these figures does not differ from that
obtained by the use of the solvent employed when
used alone. The virus of symptomatic anthrax is
destroyed by forty-eight hours' exposure to a solu-
tion of salicylic acid of 1 : 1,000, and by saturated
salicylic alcohol (Arloing, Cornevin, and Thomas).
Salicylic acid dissolved in oil and in alcohol, in 5 per
cent solution, does not destroy the spores of the
anthrax bacillus (Koch). 1 : 200 destroys the bac-
teria of sour milk (Molke). 1 : 343 killed the
bacteria of beef-tea, and 1 : 1,121 prevented the de-
velopment of bacteria in unboiled meat-infusion
exposed to the air (de la Croix). The bacteria
of tobacco-infusion were destroyed by 1 : 362,
and their multiplication prevented by 1 : 932
(Bucholz). 1 : 724 prevented the development
of bacteria in a vegetable infusion, and 1 : 1,000
in a solution of egg-albumen (Kiihn).
Soda. — Caustic soda destroys the virulence of
septicaemic blood in the proportion of 1 : 400 (S).
A one-in-five solution of soda destroys the virus
GERMICIDES AND ANTISEPTICS. 231
of symptomatic anthrax when fresh, but has no
effect upon dried virus (Arloing, Cornevin, and
Thomas).
Sodium Biborate. — The results obtained with
this salt correspond, in the writer's experiments,
with those given by boric acid. The virulence of
septic blood, as shown by inoculation of rabbits,
was destroyed by 2.5 per cent, while 1.25 per cent
failed. That this is not due to germicide power
is shown by the fact that a saturated solution
does not kill the septic micrococcus, as proved by
culture-experiments. It also failed with B. termo
and the M. of pus. The multiplication of all of
these organisms was, however, prevented by the
presence of 1 : 200 in a culture -fluid, and B. termo
failed to multiply in the presence of 1 : 400 (S).
A 20 per cent solution does not destroy the viru-
lence of the virus of symptomatic anthrax, as
proved by inoculation experiments (Arloing,
Cornevin, and Thomas). In the proportion of
1 : 107, the development of bacteria in unboiled
beef-infusion is prevented, while 1 : 161 failed.
1 : 12 failed to kill the bacteria in broken down
beef-tea (de la Croix).
Sodium Chloride, in 5 per cent solution, failed
to destroy the virulence of septicaemic blood (S).
Common salt ranks low as a preventive (Dougall).
It is well known that meat may become putrid in
a weak solution of brine, but the extended use of
salt as a preservative agent demonstrates its anti-
septic power, when used in a sufficiently strong
232 GERMICIDES AND ANTISEFIICS.
solution. It is doubtful, however, whether infec-
tious disease germs (spores) would be destroyed
by the most concentrated solution. " A saturated
solution of cloride of sodium did not destroy the
virus of symptomatic anthrax in forty-eight hours'
contact" (Arloing, Cornevin, and Thomas).
Sodium Hyposulphite. — This salt, in the writer's
experiments, gave no evidence whatever of germi-
cide power. In saturated solution it failed to kill
the bacteria in broken-down beef-tea, and the M.
of pus was not destroyed by exposure for two
hours to a thirty-two per cent solution. Nor was
the development of the last-named organism pre-
vented by the presence of this salt in a culture-
solution in the proportion of eight per cent (S).
Exposure for forty-eight hours to a fifty per cent
solution does not destroy the virus of symptomatic
anthrax (Arloing, Cornevin, and Thomas). Chloride
of lime, hard soap, chloral um, and common salt
are low preventives. The hyposulphite, borate, and
sulphate of soda are useless as such (Dougall).
Sodium Sulphite. — The results obtained corre-
spond with those reported in the case of sodium
hyposulphite (S.)
Sodium Salicylate failed to destroy any of the test-
organisms used in the writer's experiments, in the
proportion of four per cent. But the virulence of
septicsemic blood was destroyed by 1.25 per cent ;
it must therefore have a restraining influence upon
the development of the septic micrococcus, and
doubtless upon other forms of bacteria also.
GERMICIDES AND ANTISEPTICS. 233
Sulphuric Acid destroys B. termo and the two
species of micrococcus experimented upon in the
proportion of 1 : 200 ; but a four per cent solution
failed to destroy the bacteria in broken-down beef-
tea (old stock), doubtless because of the presence
of reproductive spores. The multiplication of the
bacteria mentioned was prevented by the presence
of this acid in a culture-solution, in the proportion
of 1 : 800 (S). One part in 3,353 prevented the
development of bacteria in unboiled meat-infusion,
and 1 : 72 destroyed the bacteria of broken-down
beef- tea (de la Croix). One part in 161 destroyed
bacteria developed in tobacco-infusion (Bucholz).
Sulphurous Acid. — Exp. No. 35, Jan. 15, 1880.
— Five children were vaccinated from ivory points
which had been exposed for six hours to an atmos-
phere (dry) containing one per cent of sulphur
dioxide (collected over mercury), and with five
other points, from the same lot, not disinfected.
Result : Vaccination was unsuccessful in each case
with the disinfected points, and successful with
those not disinfected (S). In four experiments in
which <3ry vaccine was exposed to the fumes of
sulphurous acid, for ten minutes, its infecting
power was destroyed (Baxter). Sulphurous acid
has no influence upon the bacteria of symptomatic
anthrax (Arloing, Cornevin, and Thomas). It is
powerless against the spores of the anthrax bacillus
(Koch). In the proportion of 1 : 12,649, the de-
velopment of bacteria in uncooked beef-infusion is
prevented, and in 1 : 135 it destroys the vitality
234 GERMICIDES AND ANTISEPTICS.
of the bacteria of broken-down beef-tea (de la
Croix).
Sulphuretted Hydrogen. — Bacteria develop read-
ily in the presence of sulphuretted hydrogen
(Hamlet).
Tannic Acid, in the proportion of one per cent,
destroys the virulence of septic blood (S). A one-
in-five solution of tannic acid has no effect upon
the virus of symptomatic anthrax (Arloing, Corne-
vin, and Thomas). A five per cent solution does
not kill the spores of anthrax (Koch).
Thymol dissolved in alcohol destroys the virulence
of septicaemic blood (time of exposure half an
hour), in the proportion of 1 : 400 (S). Thymol
retards the development of anthrax spores in the
proportion of 1 : 80,000 (Koch). One part in 200
kills the bacteria of tobacco-infusion (Bucholz) ;
one part in 50 the sour-milk ferment (Molke) ;
and one in 20 the bacteria of broken-down beef-
tea (de la Croix). The development of bacteria
in unboiled beef-infusion is prevented by 1 : 1,340
(de la Croix), and in Pasteur's fluid by 1 : 2,000
(Bucholz).
Zinc Chloride destroys the micrococcus of gon-
orrhceal pus in the proportion of two per cent ;
the septic micrococcus failed to multiply after ex-
posure to one part in 200 (S). A five per cent
solution failed within a month to weaken the de-
veloping power of splenic fever spores (Koch).
Liquor zinci chloridi (Squibbs) failed to kill the
micrococcus of pus, in the proportion of eight per
cent (S).
GERMICIDES AND ANTISEPTICS. 235
Zinc Sulphate, in the proportion of twenty per
cent, does not kill the micrococcus of pus ; but in
the proportion of 1.25 per cent, it destroys the
virulence of septicaemic blood. This is no doubt
due to restraining power, and cannot be taken as
evidence that the vitality of the septic micrococcus
was destroyed (S).
PART FIFTH.
BACTERIA IN INFECTIOUS DISEASES.
No more important question has ever engaged
the attention of physicians, of sanitarians, or of
biologists, than that which relates to the role of
the bacteria in infectious diseases. The practical
results of etiological studies, so far as the preven-
tion and cure of disease are concerned, are likely
to be much greater than those which have been
gained by the study of pathological anatomy; and, if
the time ever comes, as now seems not improbable,
when we can say with confidence, infectious diseases
are parasitic diseases, medicine will have established
itself upon a scientific foundation. But this gener-
alization, which some physicians think is justified,
even now, by the experimental evidence which has
been so rapidly accumulating during the past de-
cade, would, in the opinion of the writer, be prem-
ature in the present state of science. And, for the
present, it seems wiser to encourage additional
researches rather than to attempt to generalize
from the data at hand. For much of the evidence
offered in favor of this view is open to question ;
BACTERIA IX INFECTIOUS DISEASES. 237
and even where we do not doubt the scientific
accuracy of an observer, we may differ from him
as to the interpretation of the facts which he has
recorded. Those who have had the most experi-
ence in this difficult field of investigation, are
commonly the most critical and exacting with
reference to the alleged discoveries of others.
And it is now generally admitted that the only
satisfactory proof that a certain micro-organism
bears a causal relation to a disease with which it
is associated is that which is obtained by a series
of culture experiments, in which the organism is
completely isolated from the non-living constitu-
ents of the infective material containing it, and
in the production of the disease in question by
inoculation experiments with such a " pure-cul-
ture." The unimpeachable nature of this proof,
when the experiment is properly made and fre-
quently repeated with the same result, is made
apparent in the following quotation from a paper
by the writer relating to " a fatal form of septi-
caemia in the rabbit." l
" In my previous paper I related a series of experi-
ments commenced July 6th, to which I must refer the
reader as properly introducing the following : -
" The culture-fluid (No. 6) used in Experiment No. 3
(July 26th) was laid aside in an hermetically-sealed
culture-flask until September 12th, when a minute drop
was used to inoculate sterilized bouillon in culture-tube
No. 7, This, placed in a culture-oven at 100° Fahr. for
twenty-four hours, became clouded, and upon micro-
i Med. Times, Phila., Nov. 4th, 1882, p. 81.
238 BACTERIA IN INFECTIOUS DISEASES.
scopical examination proved to be pervaded with the
identical micrococcus heretofore described and photo-
graphed (See Fig. 2, Plate IX.). A drop of culture
No. 7 was in like manner used to inoculate culture No.
8, and the next day, this being also pervaded by the
micrococcus, was used in the following experiment : —
" Exp. No. 4. — September 14th. — Injected ten
minims of culture No. 8 into a full-grown rabbit. Result :
This animal died at 9 A. M. September 15th, and a micro-
scopical examination made at once demonstrated the
presence of the micrococcus in great numbers in the
blood and in effused serum in the sub-cutaneous connec-
tive tissue.
u Remarks. — This experiment shows that the micro-
coccus retained its vitality and its full virulence at the
end of six weeks, and, very conclusively, that the viru-
lence of the culture-fluid is due to the presence of the
micrococcus, and not to a hypothetical chemical virus
found in the first instance in human saliva and subse-
quently in the blood of a rabbit inoculated with this
fluid. For the benefit of those who have not calculated
the degree of dilution which such a hypothetical chemi-
cal virus would undergo in such a series of culture ex-
periments, I submit the following simple calculation : -
"My culture-tubes contain about a fluidrachm of
sterilized bouillon. The amount of blood introduced
into culture No. 1, as seed, was considerably less than a
minim ; but for convenience I will suppose that one
minim is used each time to start a new culture, — that is,
the original material is diluted 60 times in the first cul-
ture, 3,600 times in the second, 216,000 times in the
third, and in the eighth culture it will be present in the
proportion of one part in 1,679,611,600,000,000. Yet a
few minims of this eighth culture possesses all the viru-
lence of the first.
BACTERIA IN INFECTIOUS DISEASES. 239
" Look at it from another point of view. The few
minims of culture-fluid introduced beneath the skin of
a rabbit contain a micrococcus presenting definite mor-
phological characters. The blood of the animal which
falls a victim to experimental inoculation with this fluid
is filled within forty-eight hours with the same micro-
organism in numbers far exceeding the normal histo-
logical elements, — red and white corpuscles ; yet some
very conservative physicians still claim that the invading
parasite is without import, a mere epi-phenomenon,
while the infinitesimal portion of a hypothetical chemi-
cal virus is credited with this malignant potency."
When, in addition to this, we remember that
potent chemical poisons, especially when injected
subcutaneously, act promptly, and that their poi-
sonous effect bears a relation to the dose in which
tbey are administered, whereas a rabbit subjected
to an experimental inoculation with septic blood,
or with a culture-fluid remotely inoculated with
this material, shows no signs of ill-health for many
hours, — eighteen hours or more, — and that it is
only when sufficient time has elapsed to permit of
the abundant development of the micrococcus that
serious symptoms are developed, we shall see that
but one conclusion can be drawn as regards the
role of the micrococcus.
It is by experimental evidence of tbis nature
that Koch, Pasteur, and many others have demon-
strated beyond question that the disease known as
anthrax is produced by a parasitic micro-organism,
— the Bacillus anthrads ; that the last-named in-
vestigator has established the etiological role of the
240 BACTERIA IN INFECTIOUS DISEASES.
micrococcus of fowl-cholera ; and that Koch has
proved that a form of induced septicaemia in mice,
which he has especially studied, is due to a minute
bacillus.
It has been suggested that the parasitic micro-
organism in these diseases is, perhaps, only a second-
ary cause, being merely a carrier of the non-living
ferment, which is the special poison of the disease.
This hypothesis, also, is excluded by inoculation
experiments with a pure-culture, sufficiently re-
moved from the natural infective material. For
the organisms introduced into culture No. 1, as
seed, disappear as quickly from successive cultures
as does the non-living material with which they are
associated, and we may very soon leave them out
of the account, although each successive culture-
fluid is invaded throughout by their numerous
progeny.
Having determined for a certain infectious dis-
ease that its transmissibility depends upon the
presence in the infective material of a living micro-
organism, the question naturally arises as to the
modus operandi of this parasite. Does it produce
death by appropriating something from the vital
fluid, or from the tissues invaded by it, — e. g., oxy-
gen, which is essential for the maintenance of vital
processes in the living animal ? Or does it, at the
same time that it appropriates material for its own
nutrition, evolve some poisonous chemical product
which is the immediate cause of the morbid pheno-
mena in the infected animal ? Or does ii, produce
BACTERIA IN INFECTIOUS DISEASES. 241
death by the mechanical effects which result from
its presence in such vast numbers, i. e., by blocking
up the capillaries and the formation of emboli ?
There can be little doubt that, in these acute
infectious diseases, the parasite injures its host in
all three of the ways indicated, and that a fatal
result is to be ascribed to the three causes men-
tioned conjointly.
A most difficult and important question in con-
nection with these diseases is that which relates to
the rationale of the immunity produced by protec-
tive inoculations practised by one of the methods
described in PART FOURTH of the present volume.
In these protective vaccinations, the virus used is
either greatly diluted or is modified as regards the
reproductive activity of the parasite by exposure
to oxygen, by heat, or by certain chemical re-
agents. A susceptible animal, when inoculated
with virus " attenuated " by one of these methods,
does not succumb to the attacks of the parasite,
but, after experiencing a mild form of the disease,
recovers, and is subsequently protected from the
effects of full doses of unmodified virus.
This recovery after inoculation with attenuated
virus is more easy to understand than is the subse-
quent protection. There is evidently some pro-
vision of nature by which invading organisms may
be disposed of when they do not multiply too
quickly, but which fails when they have very
great reproductive activity, and when the con-
ditions within the living animal are extremely
16
242 BACTERIA IN INFECTIOUS DISEASES.
favorable to their development. These conditions
doubtless relate mainly to the composition and
temperature of the culture-medium — i.e., of the
blood of the animal — and consequently vary in
different species of animals. But that the compo-
sition of the blood should be changed materially
and permanently in the same animal, as a result
of the mild form of disease which follows pro-
tective inoculation, it is difficult to believe. Yet
this is the explanation given by Pasteur of the
immunity afforded by such inoculations. This
change is supposed to consist in the removal of
some material essential for the nutrition of the
microbe, which is exhausted during the attack,
and never reproduced. This view is sustained
in the following language : —
" It is the life of a parasite in the interior of the body
which produces the malady commonly called 4 cholera
des poulesj and which causes death. From the moment
when this culture (i. e., the multiplication of the para-
site) is no longer possible in the fowl, the sickness can-
not appear. The fowls are then in the constitutional
state of fowls not subject to be attacked by the disease.
These last are as if vaccinated from birth for this mal-
ady, because the foetal evolution has not introduced into
their bodies the material necessary to support the life of
the microbe ; or these nutritive materials have disap-
peared at an early age.
" Certainly one should not be surprised that there
may be constitutions sometimes susceptible and some-
times rebellious to inoculation — that is to say, to the
cultivation of a certain virus, when, as I have an-
BACTERIA IN INFECTIOUS DISEASES. 243
nounced in my first note, one sees a preparation of beer
yeast made exactly like one from the muscles of fowls
(bouillon) to show itself absolutely uusuited for the
cultivation of the parasite of fowl cholera, while it is
admirably adapted to the cultivation of a multitude of
microscopic species, notably to the bacteride charbon-
neuse (Bacillus anthracis) .
" The explanation to which these facts conduct us, as
well of the constitutional resistance of some individuals,
as of the immunit}7 produced by protective inoculations,
is only natural when w,e consider that every culture, in
general, modifies the medium in which it is effected ;
a modification of the soil when it relates to ordinary
plants; a modification of plants and animals when it
relates to their parasites ; a modification of our culture
liquids when it relates to mucedines, vibrioniem, or
ferments.
44 These modifications are manifested and character-
ized by the circumstance that new cultivations of the
same species in these media become promptly difficult
or impossible. If we sow chicken-bouillon with the mi-
crobe of fowl-cholera, and, after three or four days,
filter the liquid in order to remove all trace of the
microbe, and subsequently sow anew in the filtered
liquid this parasite, it will be found quite powerless to
resume the most feeble development. The liquid, which
is perfectly limpid after being filtered, retains its limpid-
ity indefinitely.
" How can we fail to believe that by cultivation in the
fowl of the attenuated virus, we place its body in
the state of this filtered liquid, which can no longer
cultivate the microbe ? The comparison can be pushed
still further ; for, if we filter the bouillon containing the
microbe in full development, not on the fourth day of
culture, but on the second, the filtered liquid will still
244 BACTERIA IN INFECTIOUS DISEASES.
be able to support the development of the microbe,
although with less energy than at the outset. \Ve
comprehend, then, that after a cultivation of the modi-
fied (attenue) microbe in the body of the fowl, we may
not have removed from all parts of its body the aliment
of the microbe. That which remains will permit, then,
a new culture, but in a more restricted measure.
** This is the effect of a first inoculation ; subsequent
inoculations will remove progressively all the material
necessary for the development of the parasite.
" Is this the only possible explanation of the phenom-
enon ? No ; we may admit the possibility that the
development of the microbe, in place of removing or
destroying certain matters in the bodies of the fowls,
adds, on the contrary, something which is an obstacle to
the future development of this microbe. The history
of the life of inferior beings authorizes such a supposi-
tion. The excretions resulting from vital processes
may arrest vital processes of the same nature. In cer-
tain fermentations we see antiseptic products make
their appearance during, and as a result of, the fermen-
tation, which put an end to the active life of the fer-
ments, and arrest the fermentations long before they
are completed. In the cultivation of our microbe, pro-
ducts may have been formed the presence of which,
possibly, may explain the protection following inocula-
tion.
" Our artificial cultures permit us to test the truth of
this hypothesis. Let us prepare an artificial culture
of the microbe, and after having evaporated it, in vacuo,
without heat, let us bring it back to its original volume
by means of fresh chicken bouillon. If the extract con-
tains a poison for the life of the microbe, and if this is
the cause of its failure to multiply in the filtered
liquid, the new liquid should remain sterile. Now this
BACTERIA IN INFECTIOUS DISEASES. 245
is not the case. We cannot, then, believe that during
the life of the parasite certain substances are produced
which are capable of arresting its ulterior develop-
ment." — (Comptes rendus Acad. des Sc., XC. pp. 952-
958.)
It is a little surprising that after disproving, by
the experimental method, the hypothesis last men-
tioned, which had been proposed by a member of
the French Academy in explanation of the phe-
nomenon in question, Pasteur did not, in accord-
ance with his usual custom, attempt to establish
his own hypothesis upon a firm foundation by an
experiment which at once suggests itself. If a
fowl which is protected against cholera, or an
animal which is protected against anthrax, owes
this protection to the fact that a certain material
which is required for the development of the
microbe of fowl-cholera, or for the anthrax bacil-
lus, has been exhausted in the course of the modi-
fied form of the disease to which immunity is due,
then the flesh of such an animal, made into bouillon,
should not constitute a proper culture-medium for
the organisms in question. The writer ventures
to predict that the result of such an experiment
would not be favorable to Pasteur's hypothesis,
and that it will be found that the micrococcus of
fowl-cholera can be cultivated in bouillon made from
the flesh of a protected animal, and that the bacil-
lus of anthrax may multiply freely in the blood, or
in an infusion of the flesh, of an animal which,
before it was killed for the experiment, possessed
246 BACTERIA IN INFECTIOUS DISEASES.
immunity against the disease anthrax. The writer
long since proposed to himself to make the experi-
ment, but has not yet been able to do so. The
matter is mentioned here in the hope that some
one more favorably situated for pursuing experi-
mental work will consider it of sufficient impor-
tance to induce him to test it in the manner
indicated. In the meantime I take the liberty of
quoting, from a paper published in 1881, certain
extracts in which my reasons are given for doubt-
ing the correctness of the hypothesis of Pasteur,
and in which another explanation is offered : —
" Let us see where this hypothesis leads us. In the
first place, we must have a material of small-pox, and a
material of measles, and a material of scarlet fever, etc.,
etc. Then we must admit that each of these different
materials has been formed in the system and stored up
for these emergencies, — attacks of the diseases in ques-
tion, — for we can scarcely conceive that they were all
packed away in the germ-cell of the mother and the
sperm-cell of the father of each susceptible individual.
If, then, these peculiar materials have been formed and
stored up during the development of the individual,
how are we to account for the fact that no new produc-
tion takes place after an attack of any one of the dis-
eases in question ?
" Again, how shall we account for the fact that the
amount of material which would nourish the small-pox
germ, to the extent of producing a case of confluent
small-pox may be exhausted by the action of the atten-
uated virus (germ) introduced by vaccination? Pas-
teur's comparison of a fowl protected by inoculation
with the microbe of fowl-cholera, with a culture-fluid in
BACTERIA IN INFECTIOUS DISEASES. 247
which the growth of a particular organism has exhausted
the pabulum necessary for the development of additional
organisms of the same kind, does not seem to me to be a
just one, as in the latter case we have a limited supply
of nutriment, while in the former we have new supplies
constantly provided of the material — food — from which
the whole body, including the hypothetical subsfance
essential to the development of the disease-germ, was
built up prior to the attack. Besides this, we have a
constant provision for the elimination of effete and
useless products.
44 This hypothesis, then, requires the formation in the
human body, and the retention up to a certain time, of
a variety of materials, which, so far as we can see, serve
no purpose except to nourish the germs of various spe-
cific diseases, and which, having served this purpose, are
not again formed in the same system, subjected to simi-
lar external conditions, and supplied with the same kind
of nutriment.
44 The difficulties into which this hypothesis leads
certainly justify us in looking further for an explanation
of the phenomenon in question. This explanation is, I
believe, to be found in the peculiar properties of the
protoplasm, which is the essential frame-work of every
living organism. The properties referred to are : the
tolerance which living protoplasm may acquire to cer-
tain agents which, in the first instance, have an inju-
rious or even fatal influence upon its vital activity, and
the property which it possesses of transmitting its pecu-
liar qualities, inherent or acquired, through numerous
generations, to its offshoots or progeny.
44 Protoplasm is the essential living portion of the cel-
lular elements of animal and vegetable tissues; but as
our microscopical analysis of the tissues has not gone
beyond the cells of which they are composed, and is not
248 BACTERIA IN INFECTIOUS DISEASES.
likely to reveal to us the complicated molecular struc-
ture of the protoplasm upon which, possibly, the proper-
ties under consideration depend, it will be best, for the
present, to limit ourselves to a consideration of the living
cells of the body. These cells are the direct descend-
ants of pre-existing cells, and may all be traced back to
the s*perm-cell and germ-cell of the parents. Now, the
view which I am endeavoring to elucidate is, that dur-
ing a non-fatal attack of one of the specific diseases, the
cellular elements implicated, which do not succumb to
the destructive influence of the poison, acquire a tol-
erance to this poison which is transmissible to their
progeny, and which is the reason of the exemption
which the individual enjoys from future attacks of the
same disease.
" The known facts in regard to the hereditary trans-
mission, by cells, of acquired properties, make it easy to
believe in the transmission of such a tolerance as we
imagine to be acquired during the attack ; and if it is
shown by analogy that there is nothing improbable in
the hypothesis that such a tolerance is acquired, we shall
have a rational explanation, not of heredity and the
mysterious properties of protoplasm, but of the partic-
ular result under consideration. The transmission of
acquired properties is shown in the budding and graft-
ing of choice fruits and flowers, produced by cultiva-
tion, upon the wild stock from which they originated.
The acquired properties are transmitted indefinitely;
and the same sap which on one twig nourishes a sour
crab-apple, on another one of the same branch is elab-
orated into a delicious pippin. . .
" The tolerance to narcotics — opium and tobacco,
and to corrosive poisons — arsenic, which results from a
gradual increase of dose, may be cited as an example of
acquired tnli-rance by living protoplasm to poisons,
BACTERIA IN INFECTIOUS DISEASES. 249
which at the outset would have been fatal in much
smaller doses.
" The immunity which an individual enjoys from any
particular disease must be looked upon as a power of
resistance possessed by the cellular elements of those
tissues of his body which would yield to the influence
of the poison in the case of an unprotected person. . . .
The resistance of living matter to certain destructive
influences is a property depending upon vitality. Thus,
living protoplasm resists the action of the bacteria of
putrefaction, while dead protoplasm quickly undergoes
putrefactive changes." — Am. J. of the Med. Sciences,
April, 1881, p. 375.
The hypothesis of Pasteur would account for
the fact that one individual suffers a severe attack
and another a mild attack of an infectious disease,
after being subjected to the influence of the poison
under identical circumstances, by the supposition
that the pabulum required for the development of
this particular poison is more abundant in the body
of one individual than in the other. The expla-
nation which seems to us more satisfactory, is that
tbe vital resistance offered by the cellular elements
in tbe bodies of these two individuals was not the
same for this poison. It is well known that in
conditions of lowered vitality, resulting from star-
vation, profuse discharges, or any other cause, the
power to resist disease-poisons is greatly dimin-
ished, and, consequently, that the susceptibility of
the same individual differs at different times.
From our point of view, the blood, as it is found
within the vessels of a living animal, is not simply
250 BACTERIA IN INFECTIOUS DISEASES.
a culture-fluid maintained at a fixed temperature ;
but, under these circumstances, is a tissue, the
histological elements of which present a certain
vital resistance to pathogenic organisms which may
be introduced into the circulation.
If we add a small quantity of a culture-fluid
containing the bacteria of putrefaction to the blood
of an animal, withdrawn from the circulation into
a proper receptacle, and maintained in a culture-
oven at blood-heat, we will find that these bacteria
multiply abundantly, and evidence of putrefactive
decomposition will soon be perceived. But, if we
inject a like quantity of the culture-fluid with its
contained bacteria into the circulation of a living
animal, not only does no increase and no putrefac-
tive change occur, but the bacteria introduced
quickly disappear, and at the end of an hour or
two the most careful microscopical examination
will not reveal the presence of a single bacterium.
This difference we ascribe to the vital properties
of the fluid as contained in the vessels of a living
animal ; and it seems probable that the little
masses of protoplasm known as white blood cor-
puscles are the essential histological elements of
the fluid, so far as any manifestation of vitality is
concerned.
The writer has elsewhere suggested that the
disappearance of the bacteria from the circulation,
in the experiment above referred to, may be
effected by the white corpuscles, which, it is well
known, pick up, after the manner of amoebae, any
BACTERIA IN INFECTIOUS DISEASES.
particles, organic or inorganic, which come in their
way. And it requires no great stretch of credulity
to believe that they may, like an amoeba, digest
and assimilate the protoplasm of the captured bac-
terium, thus putting an end to the possibility of its
doing any harm.
In the case of a pathogenic organism we may
imagine that, when captured in this way, it may
share a like fate if the captor is not paralyzed by
some potent poison evolved by it, or overwhelmed
by its superior vigor and rapid multiplication. In
the latter event, the active career of our conser-
vative white corpuscle would be quickly termin-
ated, and its protoplasm would serve as food for
the enemy. It is evident that in a contest of this
kind the balance of power would depend upon cir-
cumstances relating to the inherited vital charac-
teristics of the invading parasite and of the in-
vaded leucocyte.
That different pathogenic organisms of the same
species may differ as to their power to overcome
the vital resistance of living animals is amply
proved by experiment. We have examples of this
in the attenuated virus of anthrax and of fowl-
cholera. These physiological varieties, as Pasteur
calls them, may be produced at will by one of the
methods heretofore referred to. They differ from
the unmodified virus in vital activity, and this is
especially manifested in their diminished reproduc-
tive power.
In the great laboratory of nature, like causes
252 BACTERIA IN INFECTIOUS DISEASES.
must produce similar results; and there can be
little doubt that physiological varieties, or breeds,
of the different species of bacteria are constantly
being produced and destroyed by the operation of
natural causes. Under the influence of a favorable
temperature and of abundant pabulum, these mi-
nute plants multiply abundantly ; and, in accord-
ance with the laws of natural selection, there must
be a constant tendency among them to develop
those characters which are most favorable to their
preservation, — e. g., a capacity for rapid multi-
plication, and to adapt themselves to their envi-
ronment.
If we suppose that under certain circumstances
the conditions relating to environment approach
those which would be found within the body of a
living animal, we can easily understand how a
micro-organism, which has adapted itself to these
conditions, may become a pathogenic organism,
when by any chance it is introduced into the cir-
culation of such an animal. The culture-fluid —
blood — and temperature being favorable, it is only
a question of superiority by vital resistance on the
one hand, or by reproductive activity on the
other.
That harmless species of bacteria may develop
pathogenic properties in the manner indicated,
seems extremely probable ; and we should a priori
expect that such a result would occur more
frequently in the tropics, where the elevated
temperature and abundance of organic pabulum
BACTERIA IN INFECTIOUS DISEASES. 253
furnish the favorable conditions required. In this
way we may, perhaps, explain the origin of epi-
demics of pestilential diseases, such as yellow fever
and cholera. If these diseases do not, at the pres-
ent day, originate in the manner indicated, they
at all events have their permanent abiding place
in tropical countries. Although the specific germs
of these diseases have not been demonstrated,
there is strong reason for believing that they re-
sult from the direct or indirect action of living
ferments. For there is abundant evidence to
prove that the specific poisons to which they are
due may multiply indefinitely external to the bodies of
the sick. Such multiplication is a property of liv-
ing matter only. Moreover, the conditions which
favor this multiplication — an elevated tempera-
ture and the presence of decomposing organic
material — are exactly the conditions required for
the development of low organisms.
The experimental transformation of the harm-
less hay-bacillus (B. subtilis) into the deadly Ba-
cillus anihracis has been claimed by Buchner and
by Xageli ; and Prof. Greenfield claims to have
transformed, by a series of culture experiments,
the anthrax bacillus into a harmless form not dis-
tinguishable from the hay bacillus. Koch insists,
however, that these are distinct species, and the
weight of evidence seems to be in favor of this
view. However this may be, it is beyond ques-
tion that the anthrax bacillus may undergo a re-
markable modification as regards virulence; and
254 BACTERIA IN INFECTIOUS DISEASES.
Pasteur asserts that this virulence may be restored
by inoculating guinea-pigs but a day old, which
succumb to this attenuated virus, although those
which are five or six days old are proof agains it.
After several successive inoculations, older guinea-
pigs are killed, and after a time the virus becomes
sufficiently potent to destroy a full-grown animal.
Finally it regains its full activity, and will kill a
sheep.
The form of induced septicaemia in the rabbit,
which has been especially studied by the writer
(see p. 355), furnishes a good example of an in-
fectious disease resulting in one species of animal
from the introduction into its body of a micro-
organism which is harmless for other species.
This organism — a micrococcus — is commonly
found in normal human saliva, where it is asso-
ciated with various other species. Experiments
thus far made indicate that there are various
physiological varieties (breeds) of this micrococ-
cus, varying in pathogenic power ; for the saliva
of different individuals differs in virulence. This
may be accounted for by the fact that the con-
ditions are not identical. The human mouth is a
culture-apparatus in which the conditions are ex-
tremely favorable for the development of these
minute plants; the secretions from the salivary
glands afford a constant supply of pabulum, and
the temperature is maintained at a fixed point.
But the flow of saliva is more abundant in some
persons than in others; and the presence of de-
BACTERIA IN INFECTIOUS DISEASES. 2 -JO
cayed teeth and of organic material, from neglect
of the tooth-brush, may favor the development of
putrefactive bacteria, which are fatal to the spe-
cies of micrococcus which produces septicaemia in
rabbits. Differences in habit as to the expectora-
tion of the saliva or retaining it in the oral cavity,
and as to breathing through the nose or through
the mouth, will also constitute differences in the
environment of the micrococcus which can scarcely
fail to have an influence upon its physiological
characters. When the flow of saliva is rapid, and
it is not long retained in the mouth, it is evident
that an organism which multiplies rapidly will
have the advantage of one which multiplies slowly
and may survive where the other would quickly
disappear. There will also be a constant ten-
dency to develop still further this capacity for
rapid multiplication, which no doubt is an impor-
tant, if not the essential, factor in giving to a
micro-organism pathogenic power. The impor-
tance of this factor will be appreciated when we
remember that one method by which nature limits
the power for mischief of putrefactive bacteria
injected into the tissues is by a conservative
inflammatory process, which builds a wall about
the invading parasites, and confines their depreda-
tions within the narrow limits of an abscess. In
the disease produced by inoculation with saliva, or
with a culture-fluid containing the micrococcus
under consideration, owing perhaps to the rapid
development of the micrococcus, no such limiting
256 BACTERIA IN INFECTIOUS DISEASES.
wall of inflammatory exudation is established ;
and we find the subcutaneous connective tissue
diffusely infiltrated with serum which swarms
with the parasite.
The failure to restrict the inroads of the para-
site may not be due alone to its power of rapid
multiplication. It is not improbable that some
poison is produced, during its active growth, which
lowers the vital resistance of the tissues and pre-
vents the occurrence of conservative adhesive in-
flammation. And it may be that the true expla-
nation of the immunity afforded by a mild attack
of an infectious germ-disease is to be found in an
acquired tolerance to the action of a chemical poi-
son produced by the micro-organism, and conse-
quent ability to bring the resources of nature to
bear to restrict invasion by the parasite.
In the infectious disease known as hospital gan-
grene, circumstances relating to the origin, nature,
and treatment of the malady make it seem ex-
tremely probable that some species of bacterium,
ordinarily harmless, develops pathogenic proper-
ties as the result of an unusually favorable environ-
ment, and becomes the infecting agent, which, by
invading the enfeebled tissues, causes the rapidly
extending necrosis which is characteristic of this
frightful malady. This disease is developed de novo
in the surgical wards of hospitals, where numerous
patients, with profusely discharging wounds, are
brought together. Like its congeners, erysipelas
;iiid puerperal fever, it is prevented by cleanliness
BACTERIA IN INFECTIOUS DISEASES. 207
and antiseptic treatment. Its progress cannot,
however, be arrested by ordinary antiseptic appli-
cations ; for the pathogenic organism (hypothetical
as yet) invades the tissues to a certain depth, and
its destruction requires something more than a
superficial germicide action, — e. g., bromine, nitric
acid, the hot iron.
Diphtheria, also, is a disease in which there seems
to be good reason for believing that the different
degrees of virulence are due to circumstances re-
lating to the genealogy of the infecting organism,
as well as to the resisting power of the infected
individual ; and that, as in anthrax and in fowl-
cholera, physiological varieties of the pathogenic
micrococcus, to which this disease is probably due,
may be developed by special conditions relating to
its environment, either in the fauces of an infected
individual or external to the human body.
It is not alone by invading the blood or tissues
that bacteria exhibit pathogenic power. Chemical
products evolved during their vital activity, ex-
ternal to the body, or in abscesses and suppurating
wounds, or in the alimentary canal, may doubtless
be absorbed and exercise an injurious effect upon
the animal economy. Indeed, we have experi-
mental evidence that most potent poisons are pro-
duced during the putrefactive decomposition of
organic matter. The poisons, resembling the vege-
table alkaloids in their reactions, called ptomaines
by Selmi, who first obtained them from a cadaver,
are fatal' to animals in extremely minute doses.
17
258 BACTERIA IN INFECTIOUS DISEASES.
These ptomaines have also been obtained by Gau-
tier from putrid blood and from the normal secre-
tions of healthy persons, — saliva, urine, blood,
etc.
The soluble poison, sepsin, which has been
shown by the researches of Bergmann, Panum,
Burdon Sanderson, and others, to exist in putrid
blood is fatal to animals when administered in a
sufficient dose, which, however, is very small.
According to Koch five drops of blood, which has
not putrefied too long, is sufficient to kill a mouse
within a short time. After receiving an injection
of this kind the symptoms of poisoning are de-
veloped immediately r, and the animal dies in from
four to eight hours.
" In such a case the greater part of the fluid injected
is found in the subcutaneous cellular tissue of the back
in much the same condition as before it was injected.
It contains bacteria of the most diverse forms, irregularly
mixed together, and as numerous as when examined
before injection. No inflammation can be observed in
the neighborhood of the place of injection. The inter-
nal organs are also unaltered. If blood taken from the
right auricle be introduced into another mouse, no effect
is produced. Bacteria cannot be found in any of the
internal organs or in the blood of the heart.
" An infective disease has therefore not been produced
as the result of the injection. On the other hand, there
can be no doubt that the death of the animal was due
to the soluble poison, sepsin.
" This supposition is confirmed by the fact' that when
BACTERIA IN INFECTIOUS DISEASES. 259
less fluid is introduced into the animal the symptoms of
poisoning which follow are less marked, and are quite
absent when one or at most two drops have been in-
jected." l
On the other hand, the infectious disease which
results in certain cases from a similar inoculation
produces death only at the end of forty to sixty
hours, and is attended with definite pathological
lesions and the presence of a minute bacillus in
the blood and tissues of the infected animal. A
very small quantity (e. g., one-tenth of a drop) of
the fluid of the subcutaneous oedema, or of blood
from the heart of such an animal, is sufficient to
infect another, and Koch has fully demonstrated
the infectious nature of the disease by a series of
seventeen successive inoculations. He says : " It
is sufficient, in order to bring about the death of
the animal in about fifty hours, to pass the point
of a small scalpel, which has been in contact with
the infected blood, over a small wound in the skin."
This distinction between septic toxaemia and in-
fectious septicaemia, which has been established by
the experimental researches of Koch, Pasteur, and
many others, is opposed to the results reported by
Rosenberger of Wurzburg, who claims to have
demonstrated that the various forms of septic
micro-organisms appear in the body of an animal
which has been subjected to experimental inocula-
tion, not because like organisms have been intro-
1 Traumatic Infectious Diseases, Sydenham Society's translation,
London, 1880, p. 35.
260 BACTERIA IN INFECTIOUS DISEASES.
duced as seed, but as a result of the introduction
of a chemical poison which causes organisms pre-
viously present in the body of the animal to make
their appearance in the blood, etc.
That the injection of sepsin favors the develop-
ment of bacteria introduced at the same time is
very probable, and we cannot help believing that
Kosenberger has unwittingly introduced living
bacteria with his cooked septic blood and serum,
notwithstanding the precautions which he claims
to have taken. This view is supported by the ex-
periments of Zuelzer and Sonnenschein, who,
finding a resemblance between the physiological
effects of sepsin and of atropia, injected two to
five centigrammes of neutral sulphate of atropia
at the same time with a culture-solution contain-
ing bacteria. Fatal septicaemia was found to re-
sult from these inoculations, while the bacteria
injected alone did no harm.
The subcutaneous injection of other potent poi-
sons has been found to be followed by local necro-
sis and rapidly developed putrefactive changes ;
but there is reason to believe th&t in these in-
stances, also, the putrefactive germs are intro-
duced simultaneously with the chemical poison, or
find their way through the inoculation wound from
the exterior, rather than to suppose that they are
developed within the body of the animal. For
the observations and experiments of numerous
investigators are opposed to the belief that bacte-
ria are habitually present in the blood and tissues
BACTERIA IN INFECTIOUS DISEASES. 261
of living animals. They are known to infest the
alimentary canal, and it is probable that the small-
est portion of hair or epithelium detached from
the surface of the body of any one of the lower
animals would fertilize a culture-solution ; but
blood drawn from the veins with proper precau-
tions does not fertilize a sterilized culture-solution.
Koch sa3^s (/. c.) " I have on many occasions exam-
ined normal blood and normal tissues by means
which prevent the possibility of overlooking bac-
teria, or of confounding them with granular masses
of equal size; and I have never, in a single in-
stance, found organisms. / hare, therefore, come to
the conclusion ihat bacteria do not occur in the Hood, nor
in the tissues of the hcatthy living body, either of man or
of the lower animals."
As an example of the development of putre-
faction, as a result of inoculation by a chemical
virus, we may refer to the recent experiments of
Weir Mitchell, and Reichert, " On the Venom of
Serpents." These gentlemen find that venom
contains three proteids. One of these, venom
peptone, is not poisonous as a venom, but its in-
jection into the breast of a pigeon gives rise to
remarkable local effects. A lump forms, and with-
in forty-eight hours a gangrenous cavity is pro-
duced, from which putrefactive odors are given off.
That putrefaction here, as elsewhere, is produced
by the bacteria of putrefaction, there can be no
doubt ; for no known proteid is capable of pro-
ducing putrefactive changes in a sterilized organic
262 BACTERIA IN INFECTIOUS DISEASES.
fluid ; and that the bacteria of putrefaction were
introduced from without, is likewise altogether
probable, inasmuch as we have no account of
special precautions having been taken to exclude
these ubiquitous organisms, and in view of what
has just been said as to their absence from the
blood and tissues of healthy animals.
Panum found that a putrid solution boiled for
eleven hours still produces symptoms of putrid
poisoning, and that when such a fluid is evapo-
rated to dryness, and the residue extracted, first
with alcohol and then with water, the alcoholic
extract does not produce the symptoms, while the
watery extract does. There can be little doubt
that the watery extract injected contained living
bacterial germs, not from the putrid fluid operated
upon, but in the water used for making the ex-
tract (cold), in the syringe used for injecting it, or
possibly carried from the surface of the body of
the animal by the point of the needle used in
making the injection. According to this explana-
tion, germs introduced in the way indicated would
multiply and produce putrefactive decomposition
because the vitality of the tissues was reduced or
destroyed by the chemical poison; whereas if intro-
duced alone, even in vastly greater numbers, they
could do no harm, owing to the vital resistance of
the tissues. The writer has frequently injected
culture-fluids containing the bacteria of putrefac-
tion beneath the skin of a rabbit, without serious
result. But the smallest drop of fluid containing
BACTERIA IN INFECTIOUS DISEASES. 263
the oval micrococcus, which produces infectious
septicaemia in rabbits, produces a fatal result with-
in forty-eight hours ; and the virulence of blood,
or of a culture-fluid containing this micrococcus or
the anthrax bacillus (without spores), is destroyed
by exposure for ten minutes to a temperature of
140* Fahr.? whereas sepsin, the ptomaines, and
serpent virus — venom glohiline — all withstand a
boiling temperature.
In the pages which follow, the writer proposes
to pass in review the infectious diseases which,
upon evidence more or less convincing, have been
supposed to depend upon the invasion of the in-
fected animal by a parasitic micro-organism. The
limits of the present volume will, however, only
admit of a brief resume of the observations and
experimental evidence bearing upon this suppo-
sition, for each disease in the list ; and the reader
who desires fuller information, is referred to the
copious bibliography appended. For convenience
of reference, the diseases are arranged alphabeti-
cally.
PLATE VII.
FIG. 1. — Blood of guinea-pig dead of symptomatic anthrax.
Blood-corpuscles, and between them several bacilli. X 700. (From
The Practitioner, London, June, 1884, p. 426. Klein.)
FIG. 2. — Blood of guinea-pig dead of Koch's malignant oedema.
1. red blood discs ; 2. white corpuscles ; 3. single bacilli ; 4. chain
of long bacilli ; 5. leptothrix. X 700. (From The Practitioner,
London, June, 1884, p. 424. Klein.)
FIG. 3. — Spirochcete Obc.rmeieri. X 700. (From a photo-micro-
graph by Koch.)
FIG. 4. — Bacilli from the pericardial serum of a corpse, ob-
tained three days after death, in summer. X 700. (From a photo-
micrograph by Koch.)
PLATE Vll.
Fijf.l
Fitf 2
'
ANTHRAX. 265
INFECTIOUS DISEASES WHICH HAVE BEEN AS-
CRIBED TO THE PRESENCE OF BACTERIA.
ANTHRAX ; Charbon, Fr., Mtttzbrcmd, Ger. —
This is an infectious disease of animals which may
be transmitted to man by inoculation. This occurs,
occasionally, from the bite of an insect (fly) which
has been feeding upon the carcass of an infected
animal ; and also from accidental inoculation while
handling hides, wool, etc., taken from the victims
of anthrax.
The herbivora are most susceptible to anthrax ;
and in certain parts of Europe the annual losses
from this disease, among the herds and flocks of
the farmers, are very considerable.
The susceptibility of the carnivora to this and
other forms of septicaemia is very much less than
that of the herbivora. This difference is probably
due to natural selection ; for the bodies of herbiv-
orous animals, dead from anthrax, have doubtless
been devoured by the carnivora from the earliest
times (anthrax was known to the Greek and Koman
physicians) ; and, although inoculation is not liable
to occur through the uninjured mucous membrane
of the mouth, or of the intestine, it could scarcely
fail to occur as a result of wounds inflicted by the
teeth and claws of the contestants for the infected
266 BACTERIA IN INFECTIOUS DISEASES.
prey. An individual difference in susceptibility to
the poison, and the survival of the fittest, would
in time be very sure to produce a race immunity.
This view is not, however, sustained by the ex-
periments of Prof. Feser upon rats. In these
experiments it was found that rats fed on flesh
do not contract anthrax, but that the same rats
when restricted to a vegetable diet fall victims
to the disease after inoculation with anthrax
fluids.
The immunity of fowls has been proved by
Pasteur to be a question of temperature. Accord-
ing to Chauveau, multiplication of the bacillus in
culture-fluids ceases at 43°. This is but little above
the normal temperature of the fowl. If, however,
the temperature is reduced two or three degrees
by immersing the lower part of its body in cold
water, the fowl becomes susceptible and dies as
the result of inoculation with a fluid containing
the bacillus.
The anthrax bacillus is said to have been ob-
served by Pollender in the blood of cattle as early
as 1849, and by Davaine in 1850. But the etio-
logical importance of the parasite was first recog-
nized by the last named observer, and was affirmed
in a series of communications to the French
Academy, made in 1863 and 1864. The experi-
ments of Davaine established the fact of the
presence of rod-shaped bacteria in the blood of
animals attacked with charbon, and that a healthy
animal into which a small quantity of this blood is
ANTHRAX. 267
injected quickly succumbs to the disease, its blood
also being invaded by the parasite.
The view that the infectious properties of an-
thrax blood depend upon the presence of this
parasite was strongly contested, and since Da-
vaine's first experimental inoculations, a host of
investigators have entered the field. The question
is admitted by all to be of the greatest importance,
and has been most thoroughly investigated by the
experimental method, every point made by those
in favor of the parasitic-germ theory having been
stoutly contested by conservative opponents. The
literature of the subject, although so recent, is
very voluminous; and the fact that the anthrax
bacillus is the essential infectious element in an-
thrax blood, and that the disease anthrax is due to
the multiplication of this parasite in the body of
an infected animal, has been established in the
face of the most exacting scientific criticism.
Klebs first showed that anthrax blood loses its
infectious properties after filtration, while the fil-
trate is virulent ; but as other solid elements
(fibrine and globules) were retained as well as the
bacilli, this was not accepted as proof that the
latter were the essential infectious particles.
This proof has been furnished by inoculation
experiments with pure-cultures of the anthrax
bacillus, which have now been made by numerous
experimenters in various parts of the world. By
successive cultures, in which a small amount of
material is used to inoculate a considerable quan-
268 BACTERIA IN INFECTIOUS DISEASES.
tity of the culture-fluid, we soon exclude all non-
living particles, and soluble substances as well,
contained in the material introduced as seed into
culture No. 1 (see remarks on p. 238).
In such a series, which has been carried as far
as the one-hundredth successive culture (Pasteur),
the virulence of the last culture-fluid is as great as
that of the first ; and, as the culture-fluid itself is
innocuous, this virulence can be ascribed only to
the living bacilli contained in it, which are the
direct descendants of those present in the minute
drop of anthrax blood used to inoculate culture
No. 1.
Experiments of this kind are conclusive as to
the essential etiological role of the anthrax bacil-
lus, but they do not, of course, explain its modus
operandi. Pasteur has shown that the bacillus is
aerobic, — i.e., that its development depends upon
the presence of oxygen, — and there can be no
doubt that, during its rapid multiplication in the
blood of a living animal, it deprives this fluid of
its oxygen, and also of other constituents required
for its own nutrition. The deprivation of oxygen
is shown by the symptoms, — dyspnoea, cyanosis,
depressed temperature, and finally death, with all
the symptoms of asphyxia. It also acts mechan-
ically, by blocking up the capillaries, and pro-
ducing emboli and hemorrhagic extravasation in
various parts of the body. In addition to this, we
have evidence that, as in other forms of septicae-
mia, a potent chemical poison is produced as a re-
ANTHRAX. 269
suit of vital processes connected with the nutrition
of the bacillus. Paul Bert has been able to isolate
a poison, diffusible in liquid, which kills in twelve
hours. This he accomplished by destroying the
bacillus in a fluid containing it by means of com-
pressed oxygen. Toussaint, also, by injecting fil-
tered anthrax blood, obtained evidence of the
presence in it of a poison which, in his experi-
ments, produced only a local inflammation, with-
out any noticeable constitutional symptoms.
The discovery, which we owe to Koch, that,
under favorable conditions, the anthrax bacillus,
either in culture-fluids or in the body of a dead
animal, develops refrangant, endogenous spores,
which have great resisting power against heat and
chemical reagents, and may be preserved for years
without loss of vitality, has enabled us to account,
in a most satisfactory manner, for certain facts
which previously seemed to be irreconcilable with
a belief in the parasitic-germ theory. Thus Bert
treated anthrax blood, which he had received from
Alfort, with three times its volume of absolute
alcohol, then washed the coagulum in alcohol, and
dried it in vacuo. This material, mixed with water
and again precipitated by alcohol, proved to be
virulent when injected into guinea-pigs. Even
after remaining for five months immersed in alco-
hol, this virus had not lost its potency.
These facts were explained by Pasteur, and, in a
subsequent communication, Bert himself explained
the mystery. Further experiments had convinced
270 BACTERIA IN INFECTIOUS DISEASES.
him that virulent fluids containing anthrax rods
did not resist either alcohol or compressed oxy-
gen, and that it was only when reproductive spores
were present that the ftakes of material precipi-
tated by alcohol gave evidence of virulence. Upon
microscopical examination these shining spores
were detected in the flakes in question, and their
continued vitality after the treatment indicated
was proved by their germination in a culture-
fluid.
The anthrax rods are killed by ten minutes' ex-
posure to a temperature of 54° C. (129°. 2 Fahr.),
by desiccation, and by putrefaction of the fluid con-
taining them, in the absence of oxygen ; but the
resting-spores resist prolonged boiling (Pasteur),
and are not injuriously affected by desiccation or
by putrefaction. Spores are not formed in the
rods as they are found in the body of a living
animal; but after death, under favorable circum-
stances, these rods grow into filaments in the in-
terior of which shining oval bodies are developed,
which are the spores in question. Thus the car-
cass of a dead animal may become a storehouse of
anthrax seed, which may for many years after its
death infect pastures in which the animal was
buried. But no development of spores occurs in
the absence of oxygen ; and under these circum-
stances the rods quickly disintegrate and disap-
pear. This is shown by enclosing in a tightly
corked bottle blood from an animal recently dead.
Putrefactive decomposition soon takes place, but
ANTHRAX. 271
the blood loses its virulence, and neither rods nor
spores can be discovered in it after a few days.
According to Ewart, when cultivated upon a
warm stage in albuminous fluids, the anthrax rods
become motile within a few hours, and exhibit al-
ternations of motion and quiescence. This does
not correspond with the observations of Koch, and
is probably a mistake. Magnin, on page 88 of the
present volume, in giving the specific characters
of B. anthracis, states that it is always motionless.
If the temperature is maintained at about 33° C.
(91.4° Fahr.) the rods soon grow into long homo-
geneous filaments, which in the course of four or
five hours may reach a length many times greater
(50-100 times) than the original bacilli. These
are often twisted and interlaced in the culture-
fluid. A little later the filaments, which were at
first hyaline, are seen to consist of a distinct
sheath and a central cylinder of protoplasm, which
soon undergoes segmentation, each segment being
about the length of the original rods. The spores
are formed by a consolidation of the protoplasm
of one of these segments into an oval mass, which
is subsequently set free by rupture of the cellular
envelope, or by its granular disintegration. The
oval shining spores after their escape present the
appearance of being enclosed in a gelatinous en-
velope, which according to Koch, is developed
into a new rod when germination takes place.
Other observers (Ewart, Cohn) assert that the
central protoplasm is developed into a new rod,
PLATE VIII.
Bacillus Anthracis.
FIG. 1. — Anthrax bacillis in spleen-pulp of rabbit, just dead
from an experimental inoculation made two days previously. The
spherical bodies are splenic corpuscles. Stained with Bismark
brown. X 250 diameters.
FIG. 2. — Anthrax bacillis in liver of the same rabbit ; same
staining and amplification.
FIG. 3. — Spore-bearing filament of B. anthracis, from culture in
chicken bouillon. Scattered spores, and fragments of filaments
which had broken up without producing spores, are also seen.
X 500 diameters. Methyl-violet staining.
FIG. 4. — B. anthracis in culture-solution (beef-peptone) in-
oculated twelve hours previously with material shown in Fig. 1
(spleen-pulp containing rods). X 250 diameters. Bismark brown
staining.
FIG. 5. — B. anthracis in glomerulus of kidney of same rabbit as
furnished material for Figs. 1 and 2. X 250 diameters. Bismark
brown staining.
PLATE vm.
V *Ws'»>'J^
'''•Jh£&<m£f*4i
FIG. i.
FIG. 2,
FIG. 3.
FIG. 4.
FIG. 5.
ANTHRAX. 273
and that the envelope is used up during its
growth.
At 35° C. (95° Fahr.) spores make their ap-
pearance at the end of twenty-four hours. At a
lower temperature (28° C.) the growth of the rods
into filaments takes place more slowly, and the
formation of spores is not completed in less than
thirty-six to forty-eight hours. At 42° to 43° C.
the rods grow and multiply by fission, but spores
are no longer formed. No development occurs
at temperatures below 12° C. (53.6° Fahr.). In
Fig. 3, Plate VIII., a spore-bearing filament is
seen in the centre of the field, while scattered
about are liberated spores and detached segments
of the filaments. The amplification is 500 diame-
ters, and the specimen is from a culture made
in chicken bouillon.
A statement relating to the source of the ma-
terial which furnished specimens for my photo-
micrographs, Plate VIII., may not be uninterest-
ing, as illustrating the facts already given.
While pursuing certain experimental inquiries
in the biological laboratory of Johns Hopkins
University during the summer of 1881, Professor
Martin placed in my hands a small tube just re-
ceived by him from Dr. Burdon-Sanderson, of
London. In a letter accompanying this, Burdon-
Sanderson says: "I send you the material I
started from in the last experiments I made upon
the subject (anthrax). It was then five years
old, and consequently is now seven or eight. I
274 BACTERIA IN INFECTIOUS DISEASES.
have no doubt that you will find that if worked
up with salt-solution and injected into a mouse,
you will have the spleen — after from twenty-four
to thirty-six hours — enlarged and infiltrated with
Bacillus." This scientific prediction was fulfilled
to the letter. The tube only contained a fraction
of a grain of dried blood. This was rubbed up
with a little salt-solution in accordance with the
directions given, and a few minims of the solution
injected beneath the skin of a recently-captured
mouse. The animal died in a little less than
thirty-six hours, and its liver and spleen contained
an abundance of bacilli.
A portion of the spleen of this animal was
placed in a culture-cell with a little chicken bouil-
lon, and kept for twenty-four hours in the cul-
ture-oven, at a temperature of 100° Fahr. The
following day the culture-fluid was found to con-
tain a luxuriant growth of filaments, many of
which contained shining oval spores. A fragment
of the spleen of the mouse was used to inoculate
a small quantity of blood from a healthy rabbit,
drawn directly into a sterilized tube. The an-
thrax bacillus multiplied abundantly in this blood,
growing into long filaments and forming spores,
as in the culture in chicken bouillon. On the loth,
two minims of this blood-culture were injected
into a small rabbit, and a still smaller quantity into
another mouse. The mouse died on the following
day, and the rabbit on the IGth. Upon post-
mortem examination an abundance of bacilli were
ANTHRAX. 275
found in the blood, liver, and spleen of both these
animals. My only object being to obtain a stock
of anthrax virus, and material from which to make
some photo-micrographs of Bacillus anthracis, the
experiments were not pursued any further at
this time. Some dried blood was preserved, how-
ever, and recently after an interval of three years,
this was used to inoculate a rabbit, which died
on the second day after, and furnished the mate-
rial for the photo-micrographs in Plate VIII.
These have been made with a comparatively low
power in order to show the enormous number of
bacilli in the tissues.
If we were without satisfactory experimental
evidence that the Bacillus anthracis is the cause of
the disease anthrax, we could scarcely suppose any
longer that its presence in this disease is without
import, a mere epi-phenomenon, in the face of
such evidence as that given by Koch in the
following extract from his work on " Traumatic
Infective diseases" (Sydenham Society's transla-
tion) : —
" Although I had often previously examined the
blood of animals suffering from anthrax, and had thus
formed a high estimate as to the number of bacilli pres-
ent in the body of an anthracic animal, yet I was quite
surprised when I saw for the first time sections and por-
tions of organs stained in this way [in methyl-violet,
with carbonate of potash, see p. 187J, as e.g. the in-
testinal mucous membrane and the iris of a rabbit.
When magnified fifty diameters, such a preparation
276 BACTERIA IN INFECTIOUS DISEASES.
presents, at the first glance, an appearance as if a blue
coloring matter had been injected into the vessels.
Each intestinal villus is permeated by an exceedingly
delicate blue net-work ; in the mucous membrane of
the stomach all the capillary net-work surrounding the
gastric glands is stained blue ; in the ciliary processes
each projection is injected, and a spiral vessel stained of
a dark blue color leads from thence to the iris, and
breaks up into a fine blue net-work with loops directed
towards the edge of the iris. The liver and lungs, and
the glandular structures, such as the pancreas and sali-
vary glands, are completely permeated by the same
blue capillary net-work. Indeed there is no orpin
which is not more or less injected with the blue mass.
It is, however, very striking that this injection is only
present in the capillary vessels. All the larger vessels,
even the arteries and veins of an intestinal villus, are
either not stained at all or have but a light blue streak
in their interior, and that only here and there. When
magnified 250 times one can see that the blue capillary
net-work is composed of numerous delicate rods, and
when a power of 700 diameters is used, it is found that
the apparent injection is nothing more or less than the
Bacillus anthraciSi stained dark blue, and present in in-
credible numbers in the whole capillary system. In the
other vessels, especially in the larger ones, often only a
single bacillus may be met with at long intervals, or
they may bs quite absent. Here, therefore, we have a
striking proof of how little value are conclusions drawn
in traumatic infective diseases from the examination of
a drop of blood taken from a blood-vessel by chance ;
for 'one might well take a drop of blood from the heart
and find no micro-organisms in it, or one might readily
overlook the few which might be present, and that
although the capillary system abounds in these."
ANTHRAX. 277
The results obtained by Pasteur in his experi-
ments relating to protective inoculations against
anthrax, have been of the highest importance, and
many persons have been led to share in the san-
guine expectation of the distinguished French
chemist, that not only in this disease, but in the
infectious diseases generally, protective inocula-
tions may eventually be successfully practised.
The various methods of effecting " attenuation of
virus " have been described in PART THIRD of the
present volume.
Pasteur recommends, in anthrax, a double inoc-
ulation, first with a greatly mitigated virus, pre-
mier vacci'n, and subsequently with a more potent
virus, denxieme vaccin. Whether in practice it will
be found wise to resort to protective inoculations
rather than to attempt to stamp out the disease
by the destruction of infected animals and other
vigorous preventive measures, is open to question.
As Klein has pointed out, the method of Pasteur
involves a multiplication of the poison, which may
add to the danger of extensive losses occurring
among herds and flocks which have not been pro-
tected. Moreover, there is a certain mortality
from the application of the method, and we have
not yet learned how durable the protection may
be. While, therefore, we accord full honor to
Pasteur for his valuable contributions to science in
connection with this interesting subject, we must
admit that, as a practical measure of protection,
the method is still under trial. Koch is not at all
278 BACTERIA IN INFECTIOUS DISEASES.
sanguine as to the possibility of extending the ap-
plication of the method to other infectious diseases,
and points out that even in anthrax no general
law of immunity has been established; as several
observers (Lceffler, Gotti, Guilebeau, and Klein)
have shown that no such immunity is obtained in
the case of guinea-pigs, rats, mice, and rabbits,
and that thus far only sheep and cattle have been
proved to acquire immunity from inoculations
with attenuated virus.
An interesting question, which has not yet been
definitely decided by experiment, relates to the
possible protection of an animal which has suffered
an attack of one form of septicaemia — e.g., an-
thrax— from the other allied forms. Certainly
the infectious septicaemia of rabbits, due to a mi-
crococcus, which the writer has especially studied,
bears a strong resemblance, in many particulars,
to anthrax, and the same may be said of the form
of septicaemia in mice, due to a minute bacillus,
which has been described by Koch. The question
is whether an animal which has recovered from a
modified form of one of these diseases will not be
protected from the others. If so, it is extremely
probable that protection results from tolerance to
the chemical poison evolved during the growth ot
the micro-organism, and consequent ability on the
part of the tissues to withstand the attacks of the
parasite, rather than to the using up of some ma-
terial in the body of the animal which is essential
for the development of the microbe. In this case
ANTHRAX. 279
the chemists are likely to find that the poison
present in the blood of animals suffering from
these different forms of septicaemia is the same,
although the microbes differ. According to Pas-
teur " there are as many different forms of septi-
caemia as there are different vibrios." l And in a
letter to his confrere, Dumas, he says : " Numerous
experiments have shown me that cultivation of
the bacteride (Bacillus anthracis) in a medium ex-
hausted by the microbe of fowl-cholera, although
real, is retarded, not abundant, and difficult. Con-
trary to the provisions which I have just recalled,
it may be, then, that fowls vaccinated for cholera
are refractory to charbon, which is due to a para-
site of quite a different nature. Such is precisely
the unexpected result which I have obtained in
some experiments not yet sufficiently numerous
to prove the fact."
In a later communication,2 Pasteur says : " It
may be considered as established : First. That
chickens are refractory to charbon. Second. That
chickens, when refrigerated, easily contract char-
bon. Third. That chickens in which charbon is
established by a lowering of temperature, may be
completely cured by warming them."
According to Arloing, Cornevin, and Thomas,
immunity from anthrax does not protect from the
disease which they have studied and call symp-
tomatic anthrax ; nor does immunity from the latter
disease afford protection against the former.
1 Charbon and septicaemia. Comptes rendus LXXXV.
2 Comptes rendus LXXXVII., p. 47.
280 BACTERIA IN INFECTIOUS DISEASES.
An important question, which has received the
attention of several investigators, relates to the
possibility of the passage of the bacillus from
the circulation of a pregnant female, through the
placenta, to the foetus in utero. It is well known
that the placenta does not permit of the pas-
sage of blood-corpuscles, and experimenters very
justly reasoned that if the blood of the foetus of
' an animal which has succumbed to an attack of
anthrax is free from bacilli while the mother's
blood contains them, inoculation experiments
with this blood should furnish strong evidence for
or against the germ theory.
The observations of Brauell, of Davaine, and
of Bollinger, were all in accord as to the absence
of the bacilli from the blood, and its non-virulent
character. But, more recently, Strauss and Cham-
berland have shown that there are some excep-
tions to this rule, and that occasionally the foetal
blood contains a few bacilli. This was proved by
culture experiments, and when the bacilli were
present the blood was found to be virulent, when
injected in sufficient quantity.
SYMPTOMATIC ANTHRAX ; Clwrlon tympiomaUque.
— This disease, according to Arloing, Cornevin,
and Thomas, is characterized by the presence
of a microbe which has distinct morphological
characters, and which differs essentially from the
anthrax bacillus. It is shorter and broader than
B. anil i - rounded at the extremities, is ex-
SYMPTOMATIC ANTHRAX. 281
tremely mobile, and is nearly always provided at
one extremity with a refractive spore. Sometimes
the rod is very long and has a spore at each ex-
tremity. It may happen that the microbe is only
distinguished by this spore, as the rod has nearly
the same refractive index as the fluid in which it
is found. The writer would remark, en passant ',
that he has observed bacilli which answer very
well to this description, in putrid blood, and es-
pecially in a specimen of blood sent to him from
Havana, which had become putrid en route. This
was obtained from a yellow-fever patient, post
mortem. Photo-micrographs were made of this
organism, and heliotype reproductions of these are
seen in Fig. 5, Plate II., and' Fig. 4, Plate III.
These bacilli are endowed with active motion,
have rounded extremities, and very commonly
contain a highly refractive spore at one end, as
seen in Fig. 2.
According to the authors named, symptomatic
anthrax occurs especially in young cattle, of six
months to four years, and in lambs. It is charac-
terized by. loss of appetite, debility, and lameness
due to the development of a tumor. Wherever
situated, this tumor is irregular in form, and ex-
tends in every direction with astonishing rapidity.
In eight to ten hours it attains an enormous de-
velopment. At first homogeneous and extremely
painful, the tumor becomes, little by little, insen-
sible in the centre and crepitates on pressure.
All of the tissues forming this tumor are black
282 BACTERIA IN INFECTIOUS DISEASES.
and friable. When incised, bright red blood es-
capes, in the earlier stage of development, later
a liquid resembling venous blood, and at last a
frothy serum. The tumor may be deeply buried
in the muscles, and may then escape observation.
Death usually occurs within 36 to 48 hours after
the appearance of the first symptoms. The dis-
ease is always fatal. After death the body rap-
idly becomes inflated by an accumulation of gas
in the abdomen, in the veins, and in the cellular
tissue. One or more bloody tumors are found
among the muscles, which, when incised, present
a characteristic black color, are very friable, and
infiltrated with gas. The digestive organs are
usually entirely healthy, and the liver and spleen
are normal in appearance although they contain
the microbe in abundance.
Symptomatic anthrax is not readily communi-
cated by small amounts of virus. In a few cases
only have successful inoculations been made with
the pulp of diseased glands in small quantity.
But larger amounts of the infectious material
produce the characteristic tumors. In suscepti-
ble animals a few drops of blood, or muscle pulp,
forced into the cellular tissue produces fatal re-
sults. Intra-venous injections of as much as 2.6
c.c. of the pulp from a tumor are tolerated by the
calf, sheep, and goat. A mild sickness results
from such an injection, and in rare cases death
occurs. The guinea-pig is susceptible, but the
rabbit is not. The microbe is -said to present
SYMPTOMATIC ANTHRAX. 283
different characters in the blood, in the tumors
among the muscles, and in the effused serum in
the connective tissue.
Immunity is said to result from intra-venous
injection of material containing the microbe.
Subsequent sub-cutaneous injection of pulp from
a tumor produces no results in these animals.
The value of this method has been tested by ex-
periments upon 244 animals, made under the
authority of the French Government. The re-
sults of intra-venous injection differ with the
amount of virus employed. When the quantity
is very small, general disturbances are produced
which disappear in two or three days, leaving the
subject immune. When the dose is considerable,
fatal symptomatic anthrax is produced. The ex-
perimenters suppose that in non-fatal intra-venous
injections the bacterium multiplies in the blood,
but is prevented by the endothelium of the vessels
from entering the connective tissue.
Filtration experiments show that the poison is
particulate, and the authors quoted claim to have
proved that the bacterium described by them is
the veritable cause of the disease. The experi-
ments recently made by the same authors to de-
termine the comparative value of disinfectants
for the destruction of this virus,, seem to support
their deductions as to the essential etiological role
of the microbe.
The preservation of virulence after exposure
to sulphurous acid, to alcohol saturated with cam-
284 BACTERIA IN INFECTIOUS DISEASES.
phor, etc., is accounted for by the presence of
spores. This corresponds with Koch's results as
to the resisting power of the spores of Bacillus
anthrads, which, it will be remembered, are not
found in the bacilli as they occur in the blood
and tissues of a living animal. The superior
resisting power, as regards retention of virulence,
of the fluids of symptomatic anthrax to an ele-
vated temperature is also, no doubt, due to the
presence of spores. In a recent series of experi-
ments Arloing, Cornevin, and Thomas have deter-
mined the thermal death-point of these spores.
Fresh virus lost all pathogenic power when heated
for two hours at 80° C., or by subjection to a boil-
ing temperature for twenty minutes. An attenu-
ated virus of different degrees of power could be
produced by subjecting the material to a temper-
ature lower than that which destroyed it entirely.
Thymol and oil of eucalyptus were capable of
attenuating the virus in forty-eight hours, without
destroying the vitality of the microbes.
In symptomatic anthrax, contrary to the usual
rule in anthrax, the foetal blood is virulent, and con-
tains the bacteria to which this virulence is ascribed.
CEREBRO-SPINAL MENINGITIS. — Leyden reports
the finding of "oval micrococci, in great numbers,
occurring both singly and in chains," in recent
lymph obtained by a hypodermic syringe from
beneath the pia mater of the spinal cord in a
sporadic case of this disease.
CEREBRO-SPINAL MENINGITIS. 285
CHOLERA. — Epidemiologists find it necessary
to assume the existence of a living germ in order
to explain in a satisfactory manner the origin and
epidemic extension of this disease. Evidently the
materies morU is capable of self-multiplication ex-
ternal to the human body ; and this multiplication
is conditioned by circumstances of the same kind
as those which influence the development of the
lowest organisms, — heat, moisture, and the pres-
ence of organic material to serve as nutritive
pabulum for the hypothetical germ.
Various attempts have been made to find the
cholera germ in infected atmospheres and in the
discharges of cholera patients, but thus far no
satisfactory results have been attained.
Since the above was written, Koch has an-
nounced the discovery of a bacillus believed by
him to be the much-sought cholera " germ." This
is a comma-shaped, mobile, micro-organism which
is found in the rice-water discharges of cholera
patients, and in the intestines of those dead of the
disease. When death occurs during the stage of
reaction the bacilli are not found in the contents
of the bowel, but within the mucous membrane
and in the tubular glands. Extended researches
made in Egypt, and more recently in France,
have shown the uniform presence of this bacillus
in cases of true Asiatic cholera, and its absence
from the discharges of patients suffering from sim-
ple diarrhoea, dysentery, and other intestinal dis-
orders. The bacillus forms characteristic colonies
286 BACTERIA IN INFECTIOUS DISEASES.
in gelatine cultures and causes liquefaction of the
culture medium. Efforts to inoculate the lower
animals have not been successful. Nor are they
likely to be; for several experimenters (Magen-
die, Meyer, Lindsay) had previously demonstrated
the insusceptibility of various animals, by intro-
ducing material from the stools of cholera patients
into the stomach, veins, and sub-cutaneous tissue,
with a negative result.
ERYSIPELAS. — The infectious nature of erysip-
elas has been abundantly demonstrated, both by
clinical and experimental evidence. The trans-
mission of vaccinal erysipelas from one child to
several others, and the communication of the dis-
ease by instruments previously used in dressing
erysipelatous wounds, has been noted by physi-
cians. Orth has also shown, by a series of twenty-
three experiments, that the disease may be com-
municated by inoculation from man to the lower
animals.
Numerous observers — Hiiter, Nepveu, Wilde,
Orth, Wahlberg, and others — have noted the
presence of micrococci in the inflamed tissues, and
especially in the oedema of erysipelas.
Fehleisen has recently given strong experi-
mental evidence in favor of the pathogenic role
of these micrococci. Not only has he demon-
strated their presence in every case of erysipelas
examined by him (13 cases), but he has succeeded
in cultivating them, and has successfully inocu-
lated men and animals with the cultivated micro-
ERYSIPELAS. 287
organisms. The micrococci were very numerous
in bits of skin excised from the diseased surface
in cases of erysipelas, and were commonly ar-
ranged in chains. They were never found in the
blood-vessels, and were most numerous in recently
affected parts ; here they invaded the superficial
layer of the corium and the sub-cutaneous adipose
tissue, filling the lymphatics and the lymph-
spaces. Fehleisen succeeded in cultivating these
micrococci by placing bits of excised skin upon
the surface of a jellified solution of gelatine.
Here they produced by their abundant multipli-
cation a whitish film, which was easily detached,
and was composed entirely of the organisms.
Nine rabbits were inoculated, and in eight a
characteristic erysipelatous rash was developed
after 36 to 48 hours. This was attended with
febrile disturbance at the outset. In a few days
the disease ran its course and the animals, without
exception, recovered. The inoculations were upon
the ear, both with micrococci taken directly from
a patient, and with cultivated organisms. The
disease extended from the point of inoculation to
the root of the ear, and thence to the head and
neck.
In one case the ear was amputated during the
height of the disease, and the presence of micro-
cocci demonstrated in the lymphatics of the af-
fected part.
Fehleisen also inoculated the pure, and culti-
vated, organisms upon man, with a successful
288 BACTERIA IN INFECTIOUS DISEASES.
result in six out of seven cases. The period of
incubation was from fifteen to sixty hours, after
which rigors, followed by fever, occurred ; and the
typical erysipelatous rash developed itself, and
ran the usual course.
CHOLERA OF FOWLS, cholera des poules. — Pas-
teur has furnished satisfactory experimental evi-
dence that this infectious disease of the domestic
fowl is due to a micrococcus, which he has culti-
vated for successive generations in bouillon made
from the flesh of a chicken ; but which does not
multiply in yeast-water, a culture-medium well
suited for the development of many species of
bacteria.
Inoculation of healthy fowls with a pure culture
of this micrococcus gives rise to the disease ; but
not invariably, as a marked difference in suscepti-
bility exists in different individuals. Out of eighty
fowls inoculated by Salmon, six recovered, twenty-
five were not visibly affected, and forty-nine died.
One attack protects from subsequent attacks,
and protective inoculations may be practised with
"attenuated virus " prepared by Pasteur's method,
— long exposure to oxygen.
The most potent virus is that obtained from a
fowl which dies from a chronic form of the disease.
In these cases, "the fowl, after having been very
sick, grows thinner and thinner, and resists death
for several weeks or months. When it perishes,
which occurs shortly after the parasite, located
CHOLERA OF FOWLS. 289
previously in certain organs, has passed into the
blood and increases there, we observe that what-
ever, may have been the original virulence of the
virus at the time of inoculation, that taken from
the blood of the dead fowl has a considerable viru-
lence and kills ordinarily ten times out of ten,
twenty out of twenty." When an interval of
three to eight months is allowed to elapse between
successive cultures, the virulence is modified more
or less according to the length of time. But each
degree of attenuation may be preserved through
a series of cultivations made at short intervals
(Pasteur). It is necessary to cultivate the micro-
coccus in contact with the air as it is aerobic. In
Salmon's experiments it was observed to form a
mycoderma upon the surface of the culture-fluid.
The last-named observer states that the micro-
cocci are not abundant in the blood of a fowl,
drawn from a vein during life, but that they are
more abundant in blood taken from the body after
death. Putrefaction destroys the potency of viru-
lent fluids. The thermal death-point of the micro-
coccus has been fixed by Salmon as somewhere
between 124° and 140° Fahr. Of three fowls in-
oculated with virulent blood heated to 124° for
fifteen minutes, two died ; while two fowls inocu-
lated with blood that had been heated to 140° for
the same time, remained in good health ; one was
subsequently proved to be susceptible by inocula-
1 Comptes rendus XCL, p. 375.
19
290 BACTERIA IN INFECTIOUS DISEASES.
tion with active virus, but the other resisted such
inoculation.
This corresponds very closely with the thermal
death-point of the micrococcus of septicaemia in
the rabbit, and the micrococcus of pus, as deter-
mined by the writer, and is strong evidence in
support of the view that the virulence of the fluid
containing it depends upon the vitality of the
micro-organism. The resistance to various chemi-
cal reagents, as determined by Salmon, also cor-
responds very closely with results obtained by the
writer in similar experiments with the micrococ-
cus of induced septicaemia in the rabbit. These
two species of Micrococcus, however, have distinct
physiological properties, as the writer has proved
the innocuousness of the oval micrococcus of septi-
caemia in the rabbit when injected into the muscles
of fowls. Pasteur finds no difference, morphologi-
cally, between the organism which produces the
"new disease" described by him (see p. 365), and
that which produces choUra des poules. He also
found that this micrococcus of induced septicaemia
in the rabbit does not produce the slightest ill-
effect when injected into fowls. Toussaint has
claimed that fowl-cholera and acute septicaemia in
animals, produced by the injection of the blood of
animals dead with cholera, or of animal matters
more or less putrid, are identical diseases and due
to the same parasite. He says : " Since the ex-
periments of Coze and Feltz in 1866, of Davaine,
Vulpian, Bouley, etc., and the labors of the Ger-
DIPHTHERIA. 291
man savants, it is demonstrated that certain ani-
mal matters undergoing putrefaction, inoculated
under the skin of the rabbit and of some other
animals, produces, after several inoculations, a
malady, rapidly fatal, inoculable with extremely
minute quantities, and which reproduces itself in-
definitely. The presence of a parasite in septi-
caemia which presents this character, has been
sustained, then denied. ... I can truly say, after
several series of experiments comprising more than
two hundred and fifty cases, that in the malady of
rapid form which kills the rabbit in ten to twenty
hours, and which is inoculated so easily into birds,
there exists a microbe of well-determined form and
properties, of which the action is always identi-
cal, which is that which Pasteur has so perfectly
studied, and of which I have already demonstrated
the presence in chicken cholera," l
DIPHTHERIA. — The presence of micro-organisms,
and especially of micrococci in diphtheritic exuda-
tions, has been observed by numerous investiga-
tors, and was a priori to have been expected,
inasmuch as the healthy human mouth is con-
stantly infested with micrococci and other forms
of bacteria. Oertel says : u They were discovered
as far back as 1868, by Buhl, Hueter, and myself,
in false membranes, the blood, and the tissues ; in
like manner they were demonstrated by Von Rech-
linghausen, Wassiloff, Waldeyer, Klebs, Eberth,
Heiberg, and others, in the most different organs
1 Comptes rendus XCL, p. 302.
292 BACTERIA IN INFECTIOUS DISEASES.
and tissues/' 1 The author quoted is very positive
as to the etiological role of these micrococci, and
agrees with Eberth in the statement, "Without
micrococci there can be no diphtheria." The Micrococ-
cus diphtheria, Oertel, is described as follows, in a
later work : 2 "It has an oval form, with a length
of 1-1. 5 n, and a breadth of 0.3 /* ; larger indi-
viduals, found nearer the surface, being 4.2 /* long,
and 1.1 /x broad. Where the individuals are more
scattered, they occur mostly in pairs, rarely a
number connected into a torula-like chain. When
present in masses, the cells lie so close together
that it is difficult to determine whether they are
connected or not. They are then imbedded in a
gelatinous envelope, and thus combined in masses
into a colony." 3
The inoculability of the disease has been proved
by experiments upon animals ; and filtration
experiments (Eberth) show that the infectious
element in diphtheritic exudation is participate.
Klebs, who has the credit of first resorting to the
method of " fractional cultivations," claims to have
produced diphtheria in animals by inoculating them
with pure-cultures of the micrococcus, and to have
subsequently recognized the parasite in their blood
and tissues.
According to Ewart and Simpson, the patho-
genic organism of diphtheria is a minute spore
1 Cyclopaedia of the Practice of Medicine, Ziemssen, Vol. I. p. 690.
2 Zur Aetiologie der Infectionskrankhciten, 1881.
8 Quoted from Journal Roy. Mic. Soc. Ser. II., Vol. IL p. 88.
DIPHTHERIA.
293
Fig. 10.
Copied from a photo-micrograph ; amplification 1000 diameters
which develops into long slender bacilli upon the
surface of the tonsils, etc., when for any reason
they are denuded of their superficial epithelium.
The writer, while pursuing certain experimental
investigations in Baltimore (1881) received, from
Dr. H. C. Wood, material from the fauces of
patients suffering from diphtheria, and also from
scarlet fever patients, and made photo-micrographs
of the micro-organisms found in the various speci-
mens.
In the specimens marked " scarlet fever mate-
rial," slender filaments, containing endogenous
spores, were found, which correspond with those
described by the writers named as peculiar to diph-
theria. (See Fig. 10.)
Letzerich differs from other German observers
294 BACTERIA IN INFECTIOUS DISEASES.
in regarding a true fungus, of the hyphomycetous
family, as the specific contagion of diphtheria.1
In the same " scarlet fever material," above
referred to, the mycelium of a hyphomycetous
fungus was found (Fig. 10), and also groups of
spherical bodies which seemed to be the spores of
a fungus of this nature (Fig. 11).
Numerous micrococci were
found in the specimens
marked " diphtheritic mate-
rial, Ludington," which did
not differ morphologically
from those which the writer
had previously cultivated and
photographed from normal
Flg n- human saliva. (See Fig. 1,
Copied from a photo-micrograph ; Plofo VT ^
amplification 1000 diameters.
It is apparent from what
has been said that the micrococci, bacilli (Ewart),
and fungi (Letzerich), which have been supposed
to be the cause of diphtheria, present no mor-
phological characters by which they can be dis-
tinguished from similar organisms which are
found in the mouth and fauces of patients suf-
fering from another disease in which the throat
is involved — scarlet fever, and of healthy indi-
viduals— at least so far as the micrococci are
concerned.
Morphological identity cannot, however, be
taken as proof of physiological identity, and
1 Kinnicutt in Supplement to Ziemssen's Cyclopaedia, p. 82.
DIPHTHERIA. 295
indeed we have ample evidence that certain or-
ganisms demonstrated to have pathogenic proper-
ties do not differ in form from others known to be
harmless.
The elaborate and carefully conducted inves-
tigations of Wood and Formad, made under the
auspices of the National Board of Health, give
support to the view that the micrococcus found by
them in diphtheritic exudations is the infectious
agent in this disease.
In an editorial in the "Medical Times" (April
22, 1882), Dr. Wood says :-
" A number of experiments were made upon the
effect of boiling the membrane, and it was found that if
the heat were maintained for only four or five minutes
the contagious power was not always destroyed, but
that when the boiling was continued for fifteen minutes
or longer, inoculation with the virus always failed to
produce any local or general effects. Culture experi-
ments with this innocuous virus showed that the boil-
ing had killed the micrococci, which entirely refused to
grow. It is scarcely necessary to point out the con-
firmation this lends to the belief that the micrococci are
the materies morbi. . . .
"A number of cultures were also made, and inocula-
tions with the liquid practised. In six or eight in-
stances the second, third, or fifth generation of cultured
plants caused the death of the rabbit. In all these
cases micrococci were abundant in the blood and inter-
nal organs. In some animals the local exudations were
marked, and resembled those of diphtheria ; but in other
rabbits the local symptoms were only slight swelling
and infiltration of the surrounding tissues with serous
296 BACTERIA IN INFECTIOUS DISEASES.
liquid containing an abundance of micrococci." [It
must be remembered that the injection of normal human
saliva into rabbits produces similar results.]
Wood and Formad give the following summary
statement of the conclusions reached by them as
a result of their experimental investigation, in
their final report, which has only recently been
published, although it was sent to the National
Board of Health in September, 1882 : —
" Micrococci are an essential part of the diphtheritic
process, being always found locally at the seat of
inflammation, and, when blood-poisoning develops, also
in the blood, attacking and destroying the white blood-
corpuscles, forming emboli in the kidneys, spleen, and
other organs. . . . The micrococci of diphtheria do not
differ, so far as observed, from the micrococci of furred
tongue, etc., except in their tendency to grow in culture-
fluids. . . . The theory of the disease, which we would
deduce from these facts, is that the micrococcus which
causes the diphtheria is not a specific organism different
from that common to healthy and inflamed throats, but
is an active state of that organism ; that certain cir-
cumstances outside% of the human body are capable of
throwing this common micrococcus into the condition
NOTE. — We remark that the fact mentioned on page 205, with refer-
ence to the failure of four or five minutes' boiling to destroy the conta-
gious power of diphtheritic membrane, in some instances, is opposed to
the view that the micrococcus found in it is the contagious principle ;
for the thermal death-point of this micrococcus is only 140° Fnlir., as
determined by the writer's experiments (see page 223). It may In •, how-
ever, that the masses used in the experiments in which the contagious
power was not destroyed were not penetrated by the heat, during this
short exposure, and that micrococci in the interior of the mate-rial
escaped destruction for this reason.
DISEASE PRODUCED BY BACILLI 297
of active growth, and engendering an epidemic of
diphtheria."
Several observers have noted the occurrence of
an infectious disease among fowls, attended with
the formation of false membrane in the trachea,
which is supposed by some to be identical with
diphtheria in man.
Nicati has successfully inoculated various ani-
mals with the false membrane, and states that the
outbreak among fowls studied by him coincided
with an increase of diphtheria among the inhabi-
tants in the vicinity.
DISEASE PRODUCED BY BACILLI. — Abstract of
a paper by J. Cossar Ewart, M. D., Professor of
Natural History, University of Edinburgh : —
" About the end of March of this year, a new form
of fever made its appearance in Aberdeen. The fever
began with the usual symptoms ; there was well-marked
rigor ; then a sense of coldness for some hours, accom-
panied with great depression ; the pulse was rapid, and
the temperature increased in some cases to 105° Fahr.
In the worst cases there was delirium. One of the most
characteristic symptoms was an affection of the deep
cervical glands near the angle of the jaw ; the glands
enlarged ; there was a feeling of fulness about the
throat, congestion of the tonsils, and pain along the
course of the lymphatics of the side of the neck affected.
In from twenty-four to forty-eight hours the fever sub-
sided, leaving the patient in a state of great exhaustion.
In most cases there was a relapse, which corresponded
exactly with the first attack, with the difference that
another set of glands and lymphatics was affected.
298 BACTERIA IN INFECTIOUS DISEASES.
" After this relapse, there was again apparent recov-
ery, and then a second relapse ; in some cases there
were as many as six relapses occurring regularly eveiy
second day. In nearly all the cases, recovery was slow ;
and, in some, abscesses formed near the angle of the
jaw, and in the region of the jaw. In three cases
the disease proved fatal.
44 When an inquiry was instituted, it was found that
over three hundred individuals had suffered from this
disease, and that all the sufferers had been using milk
from the same dairy. A sample of milk secured for
examination, when the epidemic was at its height, was
found to contain numerous micrococci, spores of fungi,
and spores which resembled those of Bacillus anthracis,
— the organism which is associated with splenic fever.
When cultivated, the spores germinated, first into ex-
ceedingly delicate bacilli, and then into spore-bearing
filaments. On inoculating rats with the milk contain-
ing the spores, death followed in from eighteen to
twenty-four hours. The tissues of the rats, especially
in the region of the neck, were infiltrated with bacilli,
which, on cultivation, developed into spore-bearing fila-
ments. Inoculation proved both bacilli and spores to
be as virulent as the original spores found in the milk.
Confirmatory evidence of the relation of the bacillus to
the disease was obtained by the examination of pus from
an abscess over the angle of the jaw of one of the suffer-
ers. This pus contained spores and bacilli similar to
those found in, or developed from, the milk. Rats in-
oculated with a minute quantity of the pus, suffered
and died in the same way as the rats infected with the
milk, and the milk cultivations. Further investigations
proved that the organisms had been added to the milk
along with water. . . .
"Experiments, after the methods employed by Bur-
GLANDERS. 299
don-Sanderson, Pasteur, Greenfield, and Buchner,
showed (1) that this bacillus could not be converted
into the hay bacillus (B. subtilis) ; (2) that the cultiva-
tions became gradually less active until they were quite
innocuous ; (3) that, when filaments were kept for a
time at a temperature which prevented the formation of
spores, the virulence became attenuated, and ultimately
disappeared." — British Med. Journal, Nov. 4th, 1882.
FATAL EPIDEMIC AMONG FISH CAUSED BY BAC-
TERIA.— Dr. Ogle gives an account of an epidemic
among the perch in Lake Geneva, studied by Farel
and Du Plessis. The fish became sluggish, suffered
from a bilious diarrhoea, and the anterior part of
the head and body was injected with blood. The
intestines were distended with a transparent fluid
containing myriads of bacteria. The blood was
diffluent, and contained " bacteria and vibrios "
while the fish was still living. Experiments
proved that the disease was not communicable to
batrachia or to warm-blooded animals.
Professor Huxley has given an interesting ac-
count of an infectious disease of the salmon, which
is apparently produced by a Saprolegnia identical
with that which infests the bodies of dead insects.
GLANDERS. — The discovery of the parasite of
glanders has recently been announced by Schutz
and Loeffler, who have pursued an experimental
investigation relating to the etiology of this infec-
tious disease of the horse, in Koch's laboratory in
Berlin. The parasite is said to be a bacillus re-
sembling that of tuberculosis. It is found in the
300 BACTERIA IN INFECTIOUS DISEASES.
tubercles which are characteristic of the disease.
The culture-medium employed was sterilized serum
from the blood of the horse or of the sheep. This
was inoculated with a bit cut from one of the
tumors, due precautions being taken to prevent
accidental contamination. The bacillus multiplied
abundantly in the course of a few days. Animals
of various species were inoculated with pure-cul-
tures, and were found to differ as to susceptibility.
As a rule, ulcers occurred at the point of inocula-
tion, in rabbits, guinea-pigs, mice, etc., which had
an indurated base, and the lymphatic glands in
the vicinity of these were tumefied and indurated.
When the dose was large, inflammation of the tes-
ticles, ovaries, and other organs, was liable to occur.
Some of the animals died in the course of a few
days. In these, bacilli were found which could be
propagated by cultivation, but which were smaller
than those found in the original material.
Two horses were inoculated successfully, and one
died at the end of fourteen days. Both exhibited
characteristic symptoms of the disease.
In a case of acquired glanders in man, recently
studied by Wassilieff, bacilli, resembling those de-
scribed by the authors quoted, were found in the
nasal secretion, in blood, and in pus from pustules.
They were especially abundant in the unripe pus-
tules, and nearly all contained four to six spores.
Evidence of the inoculability of glanders from
the horse to the rabbit, and from the rabbit to the
ass, has also been presented by Galtier, in a com-
munication to the French Academy of Sciences.
GONORRHOEA. 301
This author states, however, that it is not trans-
mitted with certainty, so that the rabbit cannot be
used as a test in doubtful cases, inasmuch as posi-
tive results alone are of value. In successful cases
the lesions resemble those of purulent infection,
and caseous deposits form at the point of inocula-
tion. It is only exceptionally that lesions are
found in the lungs and nasal mucous membrane.
GONORRHOEA. — The constant presence of micro-
cocci in the pus of specific urethretis has now been
verified by numerous observers. Neisser of Bres-
lau is said to have first observed them, and in a
paper published in 1879 he advances evidence in
favor of the belief that they are the cause of the
specific virulence of the fluid in which they are
found. According to this author and to Weiss
(1880), these micrococci are found in gonorrhoeal
pus from the male urethra, and in that from the
female vagina, in blenorrhcea neanotorum, and in
gonorrhoeal ophthalmia. On the other hand, Neisser
failed to find them in pus from other sources —
chancres, bubo, etc. Weiss also confirms Neisser
in this, and states that they are not present in the
secretions of simple urethretis. Eecently this
subject has been investigated in a painstaking
manner by Mr. A. S. Keyser (medical student in
the University of Maryland). His observations
fully confirm Neisser as to the constant presence
of the " gonococcus " in specific purulent dis-
charges, and its absence from non-specific pus
from various sources.
302 BACTERIA IN INFECTIOUS DISEASES.
Neisser claims that this micrococcus has distinct
morphological characters, and describes it as fol-
lows : The micrococcus, at first round, becomes
oval, and then divides transversely, forming a
pair. The individual members of this pair are
soon separated from each other by a slight inter-
val, and each becomes oval and divides at right
angles to the first line of division, thus forming a
group of four. These groups are seen in the in-
terior of the pus cells, and in some cases they are
so numerous that the cells are completely filled
with them, and resemble very closely the plasma
cells which have been described by Ehrlich (see
Figs. 12 and 13).
The writer is able to confirm Neisser, as to
the presence of these micrococci in gonorrhoea!
pus, and as regards the correctness of his descrip-
tion of their morphological characters and mode
of grouping — in pairs of oval elements and in
fours as a result of transverse division in two
directions. But his observations have not led him
to the conclusion that these morphological char-
acters are peculiar to the micrococcus of gonor-
rhoeal pus (consult bibliography for titles of his
papers upon this subject). Thus in Fig. G, Plate
VI., we have a photographic representation of a
micrococcus of the same dimensions, and which
multiplies in the same manner, which I have fre-
quently found in normal human saliva, commonly
attached to the surface of (or imbedded in the
interior of?) an epithelial cell, where it forms
GONORRHCEA. 303
little groups, as seen in the figure, exactly re-
sembling those found in the cells of gonorrhceal
pus. The photo-micrograph was made from a
specimen obtained by cultivating the organisms
found in normal saliva in an acid solution of malt
extract. In my paper published in Vol. II, No. 2,
of i(> Studies from the Biological Laboratory, Johns
Hopkins University " (Bacteria in Healthy Indi-
viduals), this micrococcus was incorrectly de-
scribed as a species of Sarcim, as " division by two
perpendicular partitions in such a manner that
multiplication takes place in two directions " is
given as a distinctive character of this genus (see
p. 96 of the present volume).
It is well known, from the observations of
numerous microscopists, that pus from various
sources — e. g., acute abscesses, surgical injuries,
etc. — contains micrococci.
Ogsten has given much attention to the study
of these, and in his report on " Micro-organisms in
Surgical Diseases," he gives figures of micrococci
which resemble very closely, if they are not iden-
tical with, the "gonococri" of Neisser. In his de-
scription of these he says : —
"In the chain-form, division occurred in only one
direction, through a plane midway between two given
poles, so that a pair of cocci growing formed a chain
of four ; this grew into a chain of eight. ... In the
grouped form, fission took place in any direction, a sin-
gle coccus seemingly dividing into two, three, or four
cocci, and a continuance of this forming the groups.
Many of the masses had evidently been produced by
304
BACTERIA IN INFECTIOUS DISEASES.
Fig. 12.
Pus cell invaded by micrococci, Ogsten. X 2600 diameters.
pairs being first formed, each of which again formed
pairs, and so on. ... In some cases, unusually large
oval cocci existed, chiefly in pairs. . . . Sufficient evi-
dence was not obtained to decide whether these differ-
ent appearances indicated different species of micrococci ;
but the constancy with which chains produced only
chains, and groups only groups, in the experiments that
fall to be detailed subsequently, rather favored the
suspicion of their being so."
The invasion of a pus cell by micrococci is
shown in Fig. 12, which is copied from the plate
accompanying Ogsten's report. When due allow-
GONORRHOEA.
305
Fig. 13.
From gonorrhoea! pas. Copied from a photo-micro-
graph. X 1000 diameters.
ance is made for
the difference in
amplification, it
must be admitted
that the resem-
blance is very
striking to the pus
cell, from gonor-
rhoeal pus, filled
with micrococci,
which is seen in
the centre of Fig.
13, which is copied
from a photo-mi-
crograph made by the writer.
In a recent series of experiments relating to the
comparative value of disinfectants, the writer had
under daily observation, for several weeks, pure
cultures of the micrococcus of gonorrhceal pus, and
of the micrococcus from pus contained in an acute
abscess (whitlow). Many successive generations
of these micro-organisms were cultivated in the
little hermetically-sealed flasks described on p. 176.
Culture No. 1, in one series, was obtained by inoc-
ulating the sterilized bouillon in such a flask with a
minute drop of gonorrhoeal pus at the moment of
its escape from the meatus iinnarius. In the other
series, a minute drop of pus from a deep-seated
abscess was used in like manner to inoculate cul-
ture No. 1 at the moment of its escape from a
deep incision. No difference was detected in the
20
306 BACTERIA IN INFECTIOUS DISEASES.
morphological characters, or in the behavior in a
culture-fluid, between the micrococci from these
two sources. In both cases multiplication oc-
curred sometimes in one direction, forming a
linear series, — torula-form, — and sometimes in
two directions, forming groups of four. Some-
times a group of three would be seen, in which
one large oval micrococcus was faced by two
smaller ones, which evidently had resulted from
the transverse division of one member of a pair
of oval elements.
My observations show that the microscopic
plants under consideration vary considerably as to
size in the same culture-fluid ; and indifferent media
they present marked differences hi this respect.
The individual cocci in a group, like that in Fig. 5,
Plate VI. may be seen, by close inspection, to
vary considerably in size. The grouping, also,
depends, to some extent, at least, upon whether
they are favorably situated for vigorous growth,
or otherwise. When in a limited quantity of
culture-fluid the pabulum required for their de-
velopment is exhausted, they settle to the bot-
tom, where they are found in little masses, or
as a pulverulent precipitate ; and the associa-
tion into chains or groups of four is no longer
observed.
The claim, then, made by Neisser, " that there
is present in the purulent discharge of gonorrhoea,
whether from urethra, vagina, or conjunctiva, a
micrococcus not found in other pus, distinguished
GONORRHCEA. 307
by its size, shape, and mode of reproduction"1
does not seem to the writer to be sustained.
My own observations, however, agree with those
of Neisser as to the constant presence of oval
micrococci, mostly arranged in groups of two and
four, in the pus of gonorrhoea — invading the pus
cells — and I have failed to observe this arrange-
ment in pus from other sources, although I have
seen it in micrococci infesting the shed epithelium
present in normal saliva. The observations of Dr.
Ogsten have, however, been far more extended
than my own, and he records the fact that, in a
certain proportion of the specimens of pus, from
acute abscesses and other sources, which he ex-
amined, this mode of grouping was seen, although
the chain-form was more common. He says : — ,
"In some cases, unusually large cocci existed, chiefly
in pairs. For the most part these varieties existed in
separate abscesses, but it frequently occurred that an
abscess contained both chains and groups. Out of sixty-
four abscesses where this point was specially noted,
seventeen contained chains only, thirty-one groups only,
and sixteen both forms, or only pairs."
In this, as in other infectious diseases, the only
satisfactory evidence that the micro-organisms
present in the virulent material are the infec-
tious agents, is to be derived from inoculation
experiments with a pure-culture. Unfortunately
for science, but not for the animals, the lower
1 Belfield, in his Cartwright Lectures. The Medical Record, Vol.
XXIII. No. 10, p. 253.
308 BACTERIA IN INFECTIOUS DISEASES.
animals commonly used in experimental studies
of this nature are not susceptible to inoculations
in the urethra, the vagina, or the conjunct! val
sac, with the most virulent gonorrhceal pus. This
fact is established by the experiments of several
independent observers, and has been verified by
the writer as regards the dog, the rabbit, and the
guinea-pig.
" Ktfnigstein has made frequent inoculation experi-
ments with the secretions of blenorrhoea neonatorum.
This was smeared into the eyes of dogs and rabbits;
and in some cases after so doing the eye was sewn up.
Here all results were negative, even those made on
puppies which were still sucking. In speaking of the
microscopic examination of the secretions, Konigstein
confirms Neisser's discovery, but does not agree with him
in considering the diplococci as characteristic of a gonor-
rhosal inflammation of a mucous membrane" (Quoted
from Keyser, italics by writer.)
Eklund also finds that the "gonococci" of Neisser
are uniformly present, but he decidedly rejects the
opinion that they constitute in an exclusive sense
the microbes of blennorrhagia, since he has dis-
covered organisms precisely similar in cases of
acute and chronic ulceration of the bowels and
lungs, and also of ulcerative stomatitis. In fact,
he regards these gonococci (to use his own ex-
pression) as a sort of pathological " sappers and
miners." But Dr. Eklund has also discovered in
pus and the superficial exudations of the inflamed
urethral mucous membrane an entirely new spe-
GONORRHCEA. 309
cies of parasite, which he denominates ediophyton
didi/odes. This, like all similar microbes, is prop-
agated by the rapid and simultaneous extension
of a vast network of mycelium-filaments into the
glands, the lacunae, and the ultimate cellules of
the affected structure.
It will be seen from the above that Dr. Belfield
is not quite right in his assertion that " The re-
ports have been, with one exception, unanimous
in corroborating Neisser's assertion in all its de-
tails" (Cartwright Lectures, /. c. p. 253). More-
over, it may be questioned whether in the array
of names presented there may not be some who
have not given sufficient attention to the study of
bacterial organisms to give much weight to their
assertion that the^ "gonococcm " of Neisser presents
distinct morphological characters.
Krause also found that rabbits, cats, and mice
were insusceptible ; but, in the case of four new-
born rabbits, successful results were obtained by
inoculations on the conjunctiva with material
from a pure culture.
Not having the original memoir of this author
at hand, the writer does not feel justified in offer-
ing an opinion as to the scientific value of the
results recorded. But it must be conceded that
the exactions of science demand (a) that rabbits
of the same age be inoculated in the same man-
ner with pus from other sources — not virulent;
(b) that the experiment be successfully repeated ;
and (c) that the virulent nature of the inflamma-
310 BACTERIA IX INFECTIOUS DISEASES.
tion produced be proved by successive inoculations
on the conjunctivas of a series of young rabbits.
In 1880 " Bokai cultivated the cocci from secretions
of (a) an acute conjunctival blenorrhcea which was a
few days old ; (6) an acute conjunctival blenorrhoea of
the second week; (e) acute gonorrhoea of the first,
second, and third weeks. Bokai does not describe his
exact method of cultivation, but contents himself with
saying, that it was done in such a way as to preclude
the presence of other organisms. Each of his culture-
fluids after two or three weeks was swarming with micro-
cocci, which were in every way identical with those
described by Neisser. With these cultivated micrococci
infection experiments were made on the human ure-
thral mucous membrane. Six students, whose self-
sacrifice in the interest of science is ever to be com-
mended, offered themselves as subjects of experiment.
In three cases an acute urethral gonorrhoea witli all
the well-known symptoms was caused." (Quoted from
Keyser.)
The fact that no details are given as to the
method of cultivation, and that the experimenter
is not known as an expert in investigations of this
kind, leaves ground for doubt as to whether pure
cultures were used in this experiment ; and there
is also room for the ungenerous suspicion that the
three victims may have contracted the disease in
the usual way. Moreover, the statement that the
culture-fluids were swarming with micrococci after
two or three weeks is contrary to the ivsults ob-
tained in a large number of experiments made by
the writer. In every instance the micrococci mul-
GONOKRHCEA. 311
tiplied abundantly in a culture-fluid during the
first twenty-four hours after it was inoculated with
gonorrhoeal pus. But after forty-eight hours all
development ceased, in consequence of the pabu-
lum being exhausted, and the micrococci fell to
the bottom of the flask.
" In September, 1882, Bockhart published his experi-
ment- in inoculating the gonococci on the sound human
urethra! mucous membrane. His description leaves noth-
ing to be desired in point of clearness. The subject of
the experiment was a forty-six-year-old paralytic, com-
pletely anaesthetic, whose death was expected daily.
The material used for infection consisted of gonococci
grown in fresh infusion of gelatine through four gen-
erations.
" The urethra of the person experimented upon was
previously perfectly sound. Forty-eight hours after in-
jection there appeared at the meatus urinarius a slight
redness, and on pressure a small quantity of mucous se-
cretion could be obtained. The symptoms increased,
and on the sixth day a typical gonorrhoea was formed,
which increased in severity up to the twelfth day, when
the man died. During the whole time the characteristic
gonococci were found in the abundant secretions."
(Quoted from Keyser.)
The criticism which the writer feels called upon
to make in this case, which is thought by Keyser
to be very convincing, is that a series of four suc-
cessive cultures is not sufficient to insure the ex-
clusion of the original material when the cultivation
is conducted upon a solid substratum. As multiplica-
tion only occurs upon the surface of the culture-
312 BACTERIA IN INFECTIOUS DISEASES.
medium, the material used to inoculate culture
No. 1 is not diluted in a series of cultures, as in
the method described on page 238, and we have
no longer the astonishing array of figures there
given to show the practical exclusion of a hypo-
thetical, non-living virus. When we consider that
material from the surface of culture No. 1 is trans-
ferred to the surface of culture No. 2, and so on,
we must admit the possibility that some of the
original material may have been transferred to
culture No. 4.
This source of error was excluded in the follow-
ing experiments : —
" The pus, from which the cultures used in these
experiments were started, was taken from cases [of
gonorrhoea in the male] in the acute stage of the dis-
ease, and which had not been subjected to any local
treatment.
"Uxp.No.4 (July, 1882). — Made by Dr. Hirsch-
felcler with material furnished by the writer. A cul-
ture fluid, fifteenth, containing the micrococcus of
gonorrhceal pus, was introduced into the urethrse of
three patients in the city and county hospital, upon
small wads of cotton which were thoroughly moistened
with the fluid, and left in situ for fifteen minutes.
"Case 1. — J. D. has been in bed for about nine
months ; caries of the vertebrae.
^Case 2. — J. B., colored; syphilitic paralysis.
"Case 3. — D. M., in bed some time; aneurism of
the abdominal aorta. The result was entirely nega-
tive.
"Exp. No. 5 (August, 1882).— A fresh culture, four-
teenth, from another, and recent, case was introduced
GONORRHOEA. 313
in the same manner into the urethra of J. D., subject of
previous experiment. Result negative.
kt Exp. No. 6 (August, 1883). — A fresh culture, thir-
teenth, was introduced into the urethra of W. B.
Result negative. . . .
" Exp. No. 15 (October 5th, 1882). — A pure culture
of the micrococcus of gonorrhoeal pus (the thirtieth cul-
ture, or above), was introduced into the urethrse of two
healthy men [G. M. S. and V. D.], by means of
pledgets of cotton wool soaked in the fluid, which were
left in situ for fifteen minutes. Result entirely nega-
tive."
A somewhat extended account has been given
of these experiments relating to the etiology of
gonorrhoea, because it is deemed a matter of great
scientific importance to determine, in a definite
manner, the relation of the micrococcus, demon-
strated to be constantly present, to the infective
virulence of the material containing it. It is evi-
dent that if a single infectious disease is shown to
be independent of all micro-organisms, no general-
ization in favor of the parasitic-germ theory will be
possible, and the etiology of each infectious disease
must be worked out separately by the experimental
method.
In the disease under consideration, it is evident
that the contradictory results reported call for
further investigation ; and, notwithstanding the
negative results which have attended his own
experimental inoculations, and the fact that the
" gotwcoccus " of Neisser has not distinctive mor-
phological characters, the writer will be very ready
314 BACTERIA IN INFECTIOUS DISEASES.
to admit the essential etiological role of this micro-
coccus whenever it is demonstrated that a pure
culture introduced into the urethra of man, or into
the conjunctival sac of young rabbits, is followed
by a specific inflammation, as shown by the viru-
lent character of the purulent discharge which
attends it.
HYDROPHOBIA. — That illustrious men are not
always infallible, is shown by the error into which
Pasteur fell in ascribing to a micrococcus com-
monly found in human saliva, the power of pro-
ducing hydrophobia. The experiments which led
to this conclusion, which was communicated to the
French Academy in 1881,1 were made with the
saliva of a child, five years of age, which died from
hydrophobia in one of the hospitals of Paris, De-
cember llth, 1880. This child had been bitten in
the face, a month previously, by a mad dog. Four
hours after death, a little buccal mucus, gathered
by means of a brush, was injected into two rabbits.
These rabbits were found dead December 13th.
Other rabbits were inoculated with the blood of
these, and death occurred even more rapidly.
Successive inoculations, repeated many times,
gave the same result. The rabbits showed at
the autopsy the same lesions. (These will be de-
scribed in the account given of induced septicaemia
in the rabbit, p. 359.)
According to Pasteur, death is produced by
1 Comptes rendus, XCII. p. 159.
HYDROPHOBIA. 315
the injection of blood or of saliva, and the blood
of the animal inoculated contains a microscopic
organism having very curious properties. Dogs
inoculated with the " new disease " fall sick im-
mediately, and usually die in a few days, without
manifesting any of the true symptoms of hydro-
phobia. Rabbits inoculated from mad dogs have
a variable period of incubation, so that the disease
in question cannot be identical with hydrophobia.
Pasteur, then, did not commit the error of de-
scribing this "new disease" as hydrophobia, but
he made the erroneous assumption that the saliva
of the child was virulent because it had died of
hydrophobia, whereas the writer has shown that
the same infectious disease results from the injec-
tion into the subcutaneous connective tissue of
rabbits of normal human saliva. This fact was
first disclosed by an experimental injection of
0.5 c.c. of my own saliva, made in New Orleans,
La., September 29th, 1880, nearly three months
prior to the death of the child from which Pasteur
obtained saliva for his experiments ; and my first
experiments in New Orleans were followed by
many others made in Philadelphia during the
month of January, 1881, and in Baltimore during
the months of June and July of the same year.
Pasteur soon became convinced that the microbe
of his " new disease " had nothing to do with
hydrophobia, and he has recently1 communicated
additional flicts of the greatest importance bearing
l Comptes rendus, XCV. pp. 1187-1192.
316 BACTERIA IN INFECTIOUS DISEASES.
upon the etiology of this disease. These facts he
has summarized as follows : —
"I. The silent (la rage mue) and furious forms of
rabies proceed from the same virus. Indeed, we have
found experimentally that one form may give rise to the
other.
"II. Nothing is more varied than the symptoms of
rabies. Each case has, so to speak, its own peculiar
symptoms, the special characters of which, there is
reason to believe, depend upon the particular part of
the nervous system, of the brain, or of the spinal mar-
row, where the virus locates itself and multiplies.
" III. The virus is associated in the saliva of a rabid
animal with various microbes ; and this saliva may
cause death, by inoculation, in three different ways:: —
" By the new microbe which we have made known
under the name of the microbe of saliva;
" By the excessive development of pus ;
" By rabies.
" IV. The medulla oblongata of a person, or of one
of the lower animals, dead from rabies, is always vir-
ulent.
" V. The virus of rabies is not only found in the me-
dulla oblongata, but also in the entire brain or a portion
thereof.
" It is also found localized in the spinal marrow, and
often in every portion of it.
" The virulence of the spinal marrow is quite equal
to that of the medulla oblongata or of the brain ; and
this is true of the inferior as well as of the superior
portions.
"So long as the brain and spinal marrow are not
invaded by putrefaction this virulence persists. At a
temperature of about 12° C. we have been able to pre-
INTERMITTENT FEVER. 317
serve the virulence of the brain of a rabid animal for
three weeks.
44 VI. In order to produce rabies with certainty and
rapidity, it is necessary to inoculate the surface of the
brain, in the cavity of the arachnoid, by means of
trephining.
44 The same result is obtained by introducing the
virus directly into the blood.
44 These methods of inoculation frequently give rise to
the disease at the end of six, eight, or ten days.
44 VII. Rabies communicated by introducing the virus
into the blood very often presents characters quite dif-
ferent from those of furious rabies, resulting from a bite
or from inoculation upon the surface of the brain, and
it is probable that many cases of silent rabies have
escaped observation. In the cases which may be denom-
inated medullary, prompt paralyses are frequent, furor
is often absent, and the rabid barkings are rare ; on the
contrary, the itching is sometimes terrible.
44 The details of our experiments lead us to believe
that, in the method by intravenous injection, the spinal
marrow is first attacked ; that is to say, that the virus
first fixes itself and multiplies in this locality."
INTERMITTENT FEVER. — The limits of the pres-
ent volume do not admit of an extended account
of the experimental evidence which has been ad-
vanced in favor of the parasitic-germ theory as
regards the etiology of the malarial fevers. The
fact that the malarial poison is evolved under cir-
cumstances which favor the development of low
organisms, and that its production has been pretty
definitely proved to be associated with the decom-
position of organic material of vegetable ori-
318 BACTERIA IN INFECTIOUS DISEASES.
gin — which has been proved to depend upon
the presence of bacterial organisms, has led many
physicians confidently to anticipate that a malarial
germ would be found in the bodies of those suffer-
ing from malarial poisoning ; and since the demon-
stration of the anthrax bacillus, and the spirillum
of relapsing fever, it seems to have been rather
hastily assumed that all disease germs are to be
sought especially in the blood. In intermittent
fever, however, it would seem, a priori, that the
hypothetical parasite would not be likely to find a
suitable culture-medium in the blood of a living
animal ; (a) because its normal habitat is in
swamps, where its development is associated with
the decomposition of vegetable matter ; and
(£) because, so far as we know, parasitic micro-
organisms, which multiply freely in the blood of
living animals, produce infectious diseases com-
municable from one individual to another, whereas
we have no evidence that this ever occurs in the
paludal fevers. Conditions more nearly approach-
ing those which favor the development of the
poison external to the body may, however, be
found in the alimentary canal, and we may sup-
pose that the germ locates itself here. Or we
may admit the possibility that its action is re-
stricted to the production of a volatile chemical
poison which is evolved as a result of its vital
activity in the localities where it abounds external
to the body; and that this infects the atmosphere
in the vicinity, and produces malarial poisoning in
INTERMITTENT FEVER. 319
those who respire this atmosphere. But this is
speculation, and cannot stand before the results
of exact experiments. Let us then briefly review
these results, or at least those which have been
most recently reported, and seem most worthy of
attention.
Passing by the researches of Salisbury and other
claimants to the honor of having discovered the
malarial parasite, we come at once to the investi-
gations of Klebs and Tommasi-Crudeli, made in
the vicinity of Rome, and as a result of which
they announced in 1879 the discovery of the
Bacillus malarice.
The evidence in favor of this discovery is stated
so concisely in an editorial in " The Medical
News " l that the writer takes the liberty of
quoting from this for his present purpose : —
" These observers found in the earth of malarial dis-
tricts, in Italy, numerous shining oval and mobile spores,
.95 of a micro-millimetre in the longer diameter. They
were able to cultivate these spores in the animal body
as well as in culture experiments, and the animals in-
fected by them exhibited not only the clinical course of
malarial disease as seen in man, but also the post mortem
appearances ; while the bacillus was also found in the
blood of such animals, taken after death. The spores
develop in the animal body, as well as in culture-experi-
ments, into long threads, which are at first homogeneous,
but later divide, while new spores develop in the interior
of the segments. The position of the spores, which are
i Philadelphia, January 13th, 1883, Vol. XLII. No. 2, p. 41.
320
BACTERIA IN INFECTIOUS DISEASES.
found either at the poles, or in the middle of the seg-
ment, serves as a mark of distinction between this and
other pathological bacilli.
u Following Klebs and
Tommasi-Crudeli, Mar-
chiafava and Cuboni, in
Italy,1 studied the blood
of men ill with malaria.
In this they found spores
and bacilli which they
declared to be identical
with those described by
the former. The spores
included in the white
blood - corpuscles were
Bacillus malaria in blood drawn during Sometimes SO numerous
life from the spleen of a person suffering
from malarial fever. (From Cuboni and
Marchiafava, in Klebs' Archiv, etc., 1881.)
N. B. These bacilli were found in one case
only.
Fig. 14.
as to seem to fill them
completely. Similar stud-
ies on malarial patients
by Lanzi, and again by
Peroncito, led to the same conclusions.
" Succeeding these, Marchand published in Virchow's
4 Archiv ' 2 some observations really made in 1876,
whence he concluded that there exists in the blood, in
the cold stage of intermittent fever, mobile arid flex-
ible rods, presenting slight swellings at their ends, and
sometimes also at the middle. These end-swellings he
thought also might be of the nature of spores.
" More recent still are the elaborate experiments of
Professor Ceri, of Camerino, Italy, published in the
'Archiv fur experimentelle Pathologic.'3 These con-
1 Archiv fur experimentelle Pathologic, Vol. XIII.
2 Vol. LX XX VIII. p. 104, April, 1882.
« Vols. XV. and XVI. 1882.
INTERMITTENT FEVER. 321
sisted of culture-experiments with organisms found in
malarial and other soils, of experiments on animals, and
culture-experiments with quinine. They resulted in
proving that the spores could be cultivated, — Ceri
applying the term natural germs to those found in the
atmosphere and soil, and artificial germs to those which
result from their culture ; that animals could be infected
by their injection into the blood, though to a less degree
by the cultivated than by the natural germs, the former
growing weaker in successive generations ; and that
the infecting properties could be retarded by the appli-
cation of heat to culture-fluids, and the introduction of
quinine into them, certain degrees of the former and
strengths (1 : 800) of the latter making the culture
of the spores impossible, and arresting the putrid fer-
mentation induced by them. The practical application
of these facts is self-evident.
" Finally the opportunity has recently been present-
ed to Dr. Franz Ziehl to test these results clinically l
in three typical cases of malaria, in all of which the
spleen was enlarged. In all three the bacilli above de-
scribed were found in the blood taken from any part of
the body by the prick of a needle, and examined in the
fresh state, or dried in a thin layer upon a cover-glass,
by simply passing the latter over a flame. These have
been preserved by Dr. Ziehl for three months without
undergoing any change.
44 The bacilli thus observed were of different lengths,
but usually were from one-fourth to the entire diameter
of a red corpuscle. The majority of those measured
were about 4 micro-millimetres long and .7 broad. Their
ends were swollen and roundish."
The evidence as here stated certainly seems very
1 Deutsche medizinische Wochenschrift, Nov. 25, 1882.
21
322
BACTERIA IN INFECTIOUS DISEASES.
Fig 15
complete, and the writer
freely admits that the nega-
tive results which he report-
ed after an attempt to repeat
the experiments of Klebs and
Tommasi-Crudeli, made under
the auspices of the National
Board of Health in New Or-
l™™> du™8 tllG Slimmer of
1880. CattDOt be given
°
The Bacilli malaria as seen
in blood obtained from a pa-
tient seized with intermittent m
fever, taken during the chill. WClght aS OppOSed to
-^ ,
But the
(From Tommasi-Crudeli.)
.
positive statements.
fact that no confirmation has yet come from Eng-
lish or American sources during the time which
has elapsed since the discovery of Klebs and
Tommasi-Crudeli was announced, constitutes nega-
tive evidence of a much stronger character. The
Bacillus malaria, according to all accounts, should
be much easier to recognize than Koch's bacillus of
tuberculosis, which has already been seen by numer-
ous physicians in nearly every large city in this
country and in Europe. But who on this side of
the Atlantic has seen the Bacillus malariw? Yet
malarial fevers are widespread, and a microscope
is to be found in nearly every physician's office.
The writer has searched faithfully for this bacillus
in the blood of patients in the Charity Hospital,
New Orleans, selected for him by Professor Bemiss
as well-marked cases of malarial fever, but admits
that he has not sought it in blood from the spleen,
or in that drawn during a chill, except in two or
INTERMITTENT FEVER, 323
three instances. He is therefore anxious to make
more extended researches whenever the opportu-
nity may offer, and will not fail to report promptly
any future observations more in correspondence
with those of the German and Italian investigators
named.
In the report of the experimental investigation
referred to, the following summary statement is
made : —
" Among the organisms found upon the surface of
swamp-mud, near New Orleans, and in the gutters
within the city limits, are some which closely resemble,
and perhaps are identical with, the Bacillus malarice of
Klebs and Tommasi-Crudeli ; but there is no satisfactory
evidence that these or any of the other bacterial organ-
isms found in such situations, when injected beneath the
skin of a rabbit, give rise to a malarial fever correspond-
ing with the ordinary paludal fevers to which man is
subject.
44 The evidence upon which Klebs and Tommasi-Cru-
deli have based their claim of the discovery of a Bacillus
malarice cannot be accepted as sufficient ; («) because
in their experiments and in my own the temperature
curve in the rabbits experimented upon has in no case
exhibited a marked and distinctive paroxysmal char-
acter; (£>) because healthy rabbits sometimes exhibit
diurnal variations of temperature (resulting apparently
from changes in the external temperature) as marked
as those shown in their charts ; (c) because changes in
the spleen such as they describe are not evidence of
death from malarial fever, inasmuch as similar changes
occur in the spleens of rabbits d,ead from septicjemia
produced by the subcutaneous injection of human saliva;
324 BACTERIA IN INFECTIOUS DISEASES.
(dT) because the presence of dark-colored pigment in the
spleen of a rabbit cannot be taken as evidence of death
from malarial fever, inasmuch as this is frequently found
in the spleens of septicsemic rabbits.
" While, however, the evidence upon which Klebs
and Tommasi-Crudeli have based their claim to a dis-
covery is not satisfactory, and their conclusions are
shown not to be well founded, there is nothing in my
researches to indicate that the so-called Bacillus malarice,
or some other of the minute organisms associated with
it, is not the active agent in the causation of malarial
fevers in man. On the other hand, there are many cir-
cumstances in favor of the hypothesis that the etiology
of these fevers is connected, directly or indirectly, with
the presence of these organisms or their germs in the
air and water of malarial localities."
It will be seen that I am not able to agree with
the editorial above quoted in the statement, that
"the animals infected by them" — i. e., the spores
of Bacillus malarice — " exhibited not only the
clinical course of malarial disease as seen in man,
but also the post mortem appearances. " On the
other hand, I do not find in the temperature-charts
published by Klebs and Tommasi-Crudeli in their
original report, and copied by me in my report
referred to, satisfactory evidence of the production
of a fever characterized by regularly recurring
paroxysms, like the ordinary paludal fevers in
man ; nor do I consider the post mortem appear-
ances sufficiently characteristic to warrant the infer-
ence that these animals died of a fever identical
with the malarial fevers to which the human race
INTERMITTENT FEVER. 325
is so subject ; especially in view of the fact, that
infection did not occur in the natural way, that the
rabbit is very subject to various forms of septi-
caemia, and that prior to these experiments no evi-
dence had ever been presented to show that the
rabbit -experiences any harm from respiring an
atmosphere charged with malaria.
Professor Ceri, however, claims to have produced
in rabbits intense febrile paroxysms of a decidedly
intermittent type, and continuing for a long period, by
the hypodermic injection of artificially cultured
malarial soil exposed for ten days to a temperature
of 35° to 40° C.
This is a very definite statement, and, if sup-
ported by temperature-charts showing the fact,
would have great weight.
In a recent report (March 18, 1883) to the
Italian Minister of Agriculture, Tommasi-Crudeli
refers to the production of intermittent (?) fevers
in the lower animals by the subcutaneous injection
of the blood of malarial-fever patients, and states
that he made extensive preparations to continue
his experiments in this direction during the year
1882 ; but he was unable to carry out his inten-
tion for the reason that not a single case of perni-
cious fever was received during that period into
the Koman hospitals.1
Here, then, we have a confession which makes it
evident that the pernicious fever, ascribed to malaria,
1 Quoted from a paper in the Med. Record of August 18, 1883, by Dr.
C. P. Russell.
326 BACTERIA IN INFECTIOUS DISEASES.
by the author referred to, differs from ordinary
malarial fevers — intermittents and remittents —
which also prevail in Italy, in the essential par-
ticular that it is an infectious disease, and may be
transmitted to the lower animals ; as well as in the
fact that it is a continued rather than a paroxysmal
fever.
The writer has long suspected that the continued
pernicious fevers of the Roman Campagna, and of
other parts of Italy, differ essentially from the or-
dinary intermittents and remittents of this country,
and that, while there is undoubtedly a malarial
element, in a certain proportion of the cases at
least, there is another etiological factor to which
the continued and pernicious form of development
manifested by the morbid phenomena must be
ascribed. We know that malaria may be associ-
ated with the specific poisons of typhoid and of
yellow fevers in such a way as to produce atypical
forms of these diseases, and it seems not impro-
bable that the Roman fever is in truth one of these
mixed or hybrid forms of disease. In this case
the bacillus of Klebs and Tommasi-Crudeli, if it
has any etiological import, is probably the factor
to which the continued and pernicious form of this
fever must be ascribed, rather than the malarial
germ, which the authors named had undertaken
to discover.
Professor Ceri's experiments relating to the
germicide power of quinine are extremely impor-
tant and interesting. But it is well to remember
INTERMITTENT FEVER. 327
that, if a dose of ten grains passed at once into
the blood of an adult weighing one hundred and
sixty pounds, the proportion which it would bear
to the whole mass of blood in the body (estimated
at twenty pounds) would be only 1 : 11,520; whereas
Professor Ceri's experiments lead him to the con-
clusion, " that the muriate of quinine in the pro-
portion of 1 : 800 prevents the development of any
infectious germs." 1
The preventive power for the Bacillus maZartce,
however, was found to be greater than this, and in
a series of eighteen experiments in which culture-
solutions were infected " with a drop of blood [con-
taining the Bacillus malarias] of a rabbit into which
had been injected cultures of malarial soil, the
development continued absent up to 1 : 2,000, and
at 1 : 2.250 it was aseptic. The Bacillus malarias
did not develop in the fertile cultures, which con-
tained only vibriones."
The writer is not disposed to underestimate the
value of these researches, but in a spirit of scien-
tific conservatism would remark as follows : —
First. — Fowler's solution of arsenic also cures
intermittent fever; and the germicide power of
this remedy is practically nil, as determined by the
writer in a series of experiments in which the
micrococcus of pus served as a test-organism. In
the proportion of forty per cent it failed to kill
this organism. Its power of restricting the devel-
1 Quoted from translation by Hugo Engel in " The Medical Times,"
Philadelphia, Dec. 16, 1882, p. 198.
328 BACTERIA IN INFECTIOUS DISEASES.
opment of the Bacillus malarice should be tested
as a check on the conclusions which may be too
hastily drawn from Professor Ceri's experiments
with quinine.
Second. — It is not impossible that the pernicious
malarial fevers of Italy may differ essentially from
the ordinary remittents and intermittents of this
country, and that their continued form is due to a
septic complication, which may result from invasion
of the blood by a pathogenic organism peculiar to
that country or to the tropical and semi-tropical
regions where pernicious fevers are most prevalent.
Third. — Fat-granules are found in the white
corpuscles of the blood of yellow fever, — which
disease resembles the pernicious malarial fevers in
many particulars, — which bear so strong a resem-
blance to the spores of bacilli that a mistake might
easily be made.1 (See p. 425.) Several of the
observers named found spores " included in the
white blood-corpuscles, which were sometimes so
numerous as to seem to fill them completely."
Fourth. — No great significance can be attached
to the finding of bacterial organisms post morion
in the blood and tissues, especially in warm cli-
mates, unless the examination is made intntcdmldf/
after death. And even then we must admit the
possibility that such organisms may migrate from
the intestine, where they are always present in
abundance, during the last hours of life, when the
circulation is feeble, and the vital resistance of the
1 Compare Fig. 3, Plate X., and Fig. 3, Plate III.
INTERMITTENT FEVER. 329
cells intervening between the lumen of the intes-
tine and of its capillary vessels is very feeble, or
quite lost.
Finally. — The writer's observations lead him to
be suspicious as regards the pathogenic role of or-
ganisms in the blood, which are few in number and
require diligent search for their demonstration.
And the possibilities of accidental contamination
are so great, when a drop of blood is drawn from
the body of a patient with the greatest possible
precautions, that the finding of a rod or of a
sphere supposed to be a bacillus or a micrococcus
requires verification by the finding of at least
several more rods or spheres of the same kind in
the same specimen ; and by the use of staining
reagents and the test of cultivation.
A more recent discovery than the Bacillus mala-
rice of Klebs and Tommasi-Crudeli is the Oscillaria
malaria* of Laveran (1881). This discovery is also
confirmed by Richard. The first-named author
says : —
" There exist in the blood of patients attacked with
malarial fever pigmented parasitic elements, which pre-
sent themselves under three principal aspects. . . .
" The parasitic elements are only found in the blood
of patients sick with malarial fever, and they disappear
when quinine is administered.
" They are of the same nature as the pigmented
bodies which exist in great numbers in the vessels and
organs of patients dead with pernicious fever, and which
have heretofore been described as melanotic leuco-
cytes."
330 BACTERIA IN INFECTIOUS DISEASES.
These parasites are described as being some-
what smaller than the leucocytes of the blood,
as sometimes resting and sometimes exhibiting
amoeboid movements, and as sometimes having
three or four long, motile filaments attached,
which are very difficult to see except when they
are in motion. They contain pigment granules,
commonly arranged in a circle. Richard states
that the malarial parasite of Laveran invades the
red blood-corpuscles, where it is first seen as a
minute round spot upon the circumference. In
other corpuscles it is larger, and about the margin
is seen a circle of black nodules. In others still
the parasite has reached such a size that only a
narrow, transparent zone remains between its
circumference and the cell-wall of the red corpus-
cle, and no trace of the haemoglobin remains.
The oscillaria is, however, still surrounded by a
ring of black nodules. The parasite now escapes
into the blood-serum. The motile filaments de-
scribed by Laveran are also referred to by Rich-
ard, who states that in some cases they alone
perforate the cell-wall of the red corpuscle, which
is moved about in a peculiar manner by their
oscillations.
The presence of these parasites was demon-
strated in the blood of every case . of malarial
fever observed by Richard, and frequently they
were very numerous.
We shall not attempt to estimate the scientific
value of these observations, but would remark
LEPROSY. 331
that Laveran and Richard, in the.ir researches,
seem not to have encountered the Bacillus malarice,
although the announcement of its discovery had
been made two years prior to the date of their
investigations, and should have prepared them to
find it if present in the blood of malarial cases
studied by them.
LEPROSY. — In 1879 Hansen, in a report to the
Medical Society of Christiania (Norway), stated
that he had " often, indeed generally, found, when
seeking for them in leprous tubercles, small, rod-
shaped bodies in the cells of the swelling." These
rods were not found, however, in blood recently
taken from leprous patients. Certain brown cells
were also described in this report as peculiar to
leprosy. In a later communication (1880) Han-
sen says : —
"I have by this preparation [staining with methyl-
violet] obtained confirmation of my earlier supposi-
tion, that the large brown bodies, after all, are nothing
else than either masses of zoogloea, or collections of
bacilli which are enclosed in cells. By looking at
Fig. 4 [Fig. 16], which represents tumor-cells treated
with osmic acid, drawn from preparations made in
1873, one is easily able to form an idea how these same
cells, by a constantly increasing number of small rods,
at last become quite overloaded, and thus obtain the
appearance of being filled with fine granules, since the
single rods cannot then be distinguished. . . .
" Since writing the above I have also been so fortu-
nate as to obtain bacilli, finely colored, in a section of
a tubercle hardened in absolute alcohol. . Bacilli
332 BACTERIA IN INFECTIOUS DISEASES.
Fig. 16.
C«lla from leprous tubercle containing the Bacillus lepree. Copied from plate illus-
trating Ilansen's paper in Quart. J. Micr. Sci., Jan. 1880.
are found in all parts of the section, either singly, or
more frequently in groups, fully corresponding to those
occurring in the cells. I furnish a drawing of two
groups taken with Zeiss's immersion system ^ and eye-
piece No. 4." (See Fig. 17.)
One observer, Kober, claims to have found the
bacillus of Hansen in the blood of leprous pa-
tients; while Edlund ascribes the disease to a
micrococcus which he finds in the blood, as well
as in the leprous tubercles. Neisser, also, says
that micrococci are always present in the epider-
mis, although he confirms Ilansen as to the pres-
LEPROSY. 333
ence of bacilli in the leprous tubercles, and also in
the liver, spleen, testicles, lymph-glands, and other parts.
( Query : How much time had elapsed between the
death of the patients and the autopsies.)
According to Neisser : —
44 The bacilli have the form
of small, slender rods, with a
length about half the diameter
of a red blood-corpuscle, and
about four times as long as
broad. They approach most
nearly the bacilli connected
with the septicaemia of the
mouse, but are not so fine."
[According to Koch, they very Fig. 17.
Closely resemble the bacillus Of Copied from Hansen's paper above
tuberculosis.] " They are in-
visible in uncolored sections, but beautifully seen when
tinctured with fuchsin and gentian-violet. Their rela-
tive position and distribution vary greatly, according to
the part where they are found. They lie either two
or three behind one another, apparently forming a long,
sometimes curved, thread ; or six or seven lie parallel
to one another ; or large numbers are associated in all
directions into a confused mass, which is only with diffi-
culty resolved into its elements. At a later stage of
the leprosy the rods break up into granules ; but
whether these are the result of disintegration, or must
be regarded as spores, is doubtful. The bacilli were
found in greatest quantities in the skin ; next to that,
in the testicles ; also in the spleen and liver ; they
were not found in the marginal parts of the lymph-
canals ; the kidneys were free from them." 1
1 Quoted from Journal of the Royal Mier. Society, Ser. II. Vol. I.
Part 2, December, 1881, p. 928.
334 BACTERIA IN INFECTIOUS DISEASES.
The presence of these bacilli in leprous tuber-
cles, etc., has been confirmed by several observers
in addition to those mentioned. Recently Dr.
Thin, an experienced microscopist and mycolo-
gist, has reported that he finds, in the skin of
Chinese lepers, a bacillus of the size and form,
and same staining qualities, as that described by
Hansen.1 It is said that the bacillus is not found
in the anaesthetic form of the disease.
The writer examined the blood of lepers in the
Charity Hospital, New Orleans, during the sum-
mer of 1880, with a negative result, so far as the
direct examination was concerned. But in cul-
ture-cells in which a drop of blood, protected from
the external air, was supplied with oxygen from a
small air-space, hermetically enclosed, micrococci
developed, which may be seen in the heliotype re-
production of a photo-micrograph made from such
a specimen, Plate II. Fig. 3.
Inasmuch as these lepers had upon the face and
hands ulcerated tubercles, the pus from which
was doubtless infested with micrococci, very little
importance was attached to the fact that micro-
cocci made their appearance in these culture-cells.
For the chances of accidental contamination, of a
drop of blood drawn from the finger, by micro-
cocci from the surface of the body, were so great
as to give but little value to the culture-experi-
ment, notwithstanding the fact that the precaution
was taken to wash the finger with alcohol before
1 British Medical Journal, Aug. 6, 1882, p. 231.
LEPROSY. 335
making the puncture. The writer's own experi-
ments have since shown that this precaution is
probably inadequate ; for the micrococcus of pus
is not killed by exposure for two hours to 25 per
cent alcohol.
Up to the present time, the supposition that the
bacillus of Hansen bears a causal relation to lep-
rosy depends for its support entirely upon the fact
that it is found in the leprous tubercles, etc. It
is not well established that these bacilli have dis-
tinctive morphological characters and staining re-
actions. Indeed, Koch finds that they closely
resemble his bacillus of tuberculosis in both these
particulars. But even if this bacillus were proved
to be peculiar to leprosy, in the absence of suc-
cessful inoculations with pure cultures its causal
relation to the disease must remain in question;
for, in view of what we know of the habits of the
bacteria generally, there is nothing improbable
in the supposition that this particular species is
able to invade tissues of a low grade of vitality,
and finds in the leprous tubercles the pabulum
necessary for its development. If, however, lep-
rosy is truly an infectious disease, which seems to
be a matter of considerable doubt, the rapidly
accumulating evidence in favor of the parasitic-
germ theory, in explanation of the etiology of
these diseases, lends strong probability to the
first-mentioned hypothesis.
Hansen has endeavored to inoculate rabbits with
leprosy, by introducing portions of the leprous
336 BACTERIA IN INFECTIOUS DISEASES.
growths, especially the tubercles, under the skin
of these animals. He says, " I was not lucky in
any of these attempts." (1880.) More recently
he has inoculated a monkey, which, at the date
of his report, had been under observation for six
months, without having developed any symptoms
of the disease. But as the time of incubation in
man is said to be a year or more, this experiment
is not considered decisive.
The bacilli have been successfully cultivated by
their discoverer upon gelatinized blood-serum. In
these cultures development commenced after an
interval of three or four days, and the bacilli
often presented nodular enlargements at the ex-
tremities, which were believed to be due to the
formation of spores. In these cultures filaments
formed, made up of a number of bacilli, and these
were often so abundant as to form an entangled
net-work. The fact that these bacilli multiply and
develop spores in a culture-solution, within a few
days, while the period of incubation in leprosy is
"at least a year," seems a little difficult to recon-
cile with the supposed etiological role of these
parasites.
MALIGNANT (EDEMA. — According to Koch, a
frequent source of error in experiments on anthrax
arises from accidental contamination of the culture-
fluids by a bacillus which closely resembles B. an-
thracix. This organism is called the bsx'illns of
malignant oedema, and the disease to which it gives
MALIGNANT (EDEMA. 337
rise has been especially studied by Gaffky, who
states that the organism is apparently identical
with the vibrion septique of Pasteur.
Although very similar to the anthrax bacillus,
Koch points out certain morphological characters
which distinguish the one from the other. The
anthrax bacilli are a little broader than the others,
and the joints have concave extremities ; whereas
the others are rounded at the extremity. B. an-
thracis is motionless, while that of malignant oedema
is usually in active motion. According to Ewart,
the anthrax bacillus, also, is motile during certain
stages in its life-history : —
" The disease is readily produced by the introduction
of a small quantity of garden-earth under the skin of an
animal (rabbit, guinea-pig, or mouse). The animals
become ill very soon, there being no distinct incubation
period, and death occurs after twenty-four to forty-eight
hours. Spreading from the point of infection, the sub-
cutaneous cellular tissue and the intermuscular cellular
tissue become oedematous and reddened, the spleen is
enlarged, soft, and of a dark reddish-blue color ; but the
other organs are not altered to the naked eye. No
bacilli, or only very few, are found in the blood of the
heart immediately after death ; but the fluid obtained
after section of the various organs contains, numbers of
these moving rods. The longer the time which has
elapsed after death, the more numerous do the bacilli
in the tissues and blood become. They grow best in the
dead body, thus differing from other pathogenic organ-
isms. On section of the organs, the bacilli are found in
the cellular tissue, almost exclusively towards the sur-
22
338 BACTERIA IN INFECTIOUS DISEASES.
face ; they apparently spread into the organs from the
cellular tissue around. They may also form plugs in
the capillaries, though this is rare. In some cases
putrefaction occurs rapidly, but in others it is apparently
retarded.
" With regard to the cultivation of these organisms
outside the body, it has been found by Pasteur, Joubert,
etc., that they will not develop in presence of oxygen,
but readily grow when carbonic-acid gas is substituted
for oxygen in the cultivating flasks. This observation is
confirmed by Gaffky, who grew them in the interior of
potatoes removed from the air. These bacilli caused
death when injected into the subcutaneous cellular
tissue, thus showing that they were the true materies
morbi.
" Of great interest is the question of the relation of
these organisms to those found by Lewis in the blood
of asphyxiated animals, especially of rats, — an observa-
tion confirmed by Gaffky. These organisms are found
most frequently in the blood of horses, and Koch ex-
plains this by the slower cooling of their bodies. In
smaller animals, these organisms, which probably come
from the intestine, do not develop rapidly, unless the
body be kept at a temperature of about 38° C. Dr.
Gaffky asphyxiated a guinea-pig, and then placed
the body in an incubator. In twenty-four hours the
body was much swollen from gas-development ; and from
the natural orifices bloody fluid exuded, containing
numerous bacilli indistinguishable from oedema bacilli.
Everywhere throughout the body, more especially in
the subcutaneous cellular tissue, these bacilli were
present in large numbers. A drop of fluid from the
cellular tissue was injected into a second guinea-pig.
This animal died on the following day, wfth the typical
appearances of malignant oedema. A minute quantity
MILK SICKNESS. 339
of the cedematous fluid, dilated with distilled water,
and injected into a third guinea-pig, was followed by
the same result."1
MILK SICKNESS. — This is an infectious disease
which prevails in certain rural districts in the
United States, and which is said gradually to
recede before the advance of improved agricul-
ture : —
" In its source, in unimproved marshy localities, it
closely resembles the malignant anthrax ; also, in its
communicability to all animals ; but it differs essen-
tially in that it fails to show local anthrax lesions, in
place of which it expends its energy on the nerve
centres, producing great hebetude and loss of muscular
power. According to Dr. Phillips it is characterized
by the presence in the blood of a microzyme (spirillum)
like that seen in relapsing fever. The germ is probably
derived from drinking-water, or the surfaces of veg-
etables, as certain wells are found to infect with cer-
tainty, and the disease has been repeatedly produced
by feeding upon particular plants (Rhus toxicodendron,
etc.). That these plants, in themselves, are not the
pathogenic elements, is shown by their innocuous prop-
erties when grown in places out of the region of the
milk-sickness infection. It seems altogether probable
that here, as in malignant anthrax, we are dealing with
a microzyme which has developed pathogenic properties,
and which can be reproduced indefinitely in the bodies
of living animals. The great danger of this affection
consists in the conveyance of the germ with unimpaired
potency through the flesh and milk, and through man-
ufactured products of the latter, — butter and cheese.
1 Quoted from The British Medical Journal, July 15, 1882, p. 99.
340 BACTERIA IN INFECTIOUS DISEASES.
Some even hold that in animals giving milk the s}rstem
does not suffer material!}', but that it is saved by the
drainage of the germs through the mammary glands,
and that thus a milk-sick cow may remain for a con-
siderable time unsuspected. . . . The disorder proves
fatal in man as in animals." 1
A careful study of this disease by the experi-
mental method would probably demonstrate its
parasitic nature ; and it is extremely desirable that
its etiology may be worked out, both in the inter-
est of science and of medicine.
MEASLES. — Coze and Feltz state that bacteria
are found in the blood of measles, of extreme
minuteness and great mobility. In the period of
invasion the nasal mucus contains small "bacteri-
form elements." The inoculation of this blood did
not produce the death of rabbits ; but these animals
were sick for two or three days, as the result of
such inoculations, and " very slender and active
rods" were found in their blood (Magnin). Klebs,
also, found micrococci in the trachea, and in blood
taken from the heart of infants that had fallen
victims to this disease. In the blood, preserved in
capillary tubes, these micrococci developed in
spherical masses.
Braidwood ai\d Vacher describe certain small
spherical bodies first found by them in the breath
of children in the acute stage of the disease, which
they believe to be the contagious elements. These
1 Prof. James Law, National Board of Health Bulletin, Vol. II. No.
4, p. 466.
PLEURO-PNEUMONIA. 341
are " sparkling, colorless bodies, something like
those found in vaccine, but larger." Some were
spherical, others were elongated, with sharpened
ends. The breath of healthy children did not
contain these sparkling bodies. These bodies
were also found in the lungs and liver of two
children who died of measles.
Keating has recently (1882) reported the find-
ing of micrococci in the blood of malignant
measles, and their absence in cases of mild type.
He says : " The micrococcus is found in the con-
tents of pustules and vesicles, and also in the
blood taken from the measles-papule in mild
cases, without its being present in the blood taken
from the punctured finger. In severe cases, called
malignant in this paper, owing to the rapid ap-
pearance of morbid symptoms, the blood shows,
early in the attack, numerous patches of micro-
coccus in the field." These observations were
verified by Formad.
PLEURO-PNEUMONIA. — The infectious disease
of cattle known as pleuro-pneumonia has been
studied experimentally by Willems, Banti, Bouley,
Leblanc, Bruylants, Verriest, and others, and
strong evidence has been adduced in favor of the
view that it is due to a parasitic micro-organism.
In 1852 Willems pointed out the existence of
certain peculiar corpuscles in the lymph obtained
by incision of the lung of an animal dead from
this disease. This observation has been confirmed
342 BACTERIA IN INFECTIOUS DISEASES.
by others, and Brnylants and Verriest describe tbe
organism, which they were able to cultivate in
sterilized fluids, as a micrococcus, sometimes isola-
ted, sometimes in pairs, and sometimes in chains
of 3-10 elements. The form is slightly oval, and
the size varies considerably, the largest measuring
1 p. in diameter.
Protective inoculations are successfully practised
in this disease.
INFECTIOUS PNEUMONIA. — That there is an in-
fectious form of pneumonia in man is now pretty
generally admitted upon clinical evidence ; and
several observers have described micro-organisms
supposed to bear a causal relation to this disease.
Klebs claims to have produced lobular pneumonia
in rabbits by injecting the sputum of patients suf-
fering from pneumonia, in which he found an or-
ganism called by him monas pulmonale. Friedlander,
also, found micro-organisms in eight successive
cases in the expectoration and in sections of pul-
monary tissue. These micrococci were elliptical
in shape, one micro-millimetre in length, and
two-thirds p, in breadth. They were usually in
pairs, but also occurred in chains, and were found
most abundantly in the fibrinous expectoration,
and in grayish-red hepatization.
The writer would call attention to the fact that
these oval micrococci seem to resemble closely those
found in the blood of a rabbit killed by the subcuta-
neous injection of human saliva. (See Fig. 3, Plate
PYJEMIA IN RABBITS. 343
VI., and also p. 359.) Leyden has demonstrated the
presence of numerous micrococci corresponding
with those described by Friedlander in exudation
fluid obtained during life from a patient suffering
from severe croupous pneumonia. The fluid was
withdrawn by means of a hypodermic syringe.
Giinther. also, has obtained the same result from
an exploratory puncture of hepatized lung. On
the other hand, negative results were obtained by
Leyden in two milder cases of pneumonia in which
fluid was withdrawn from the inflamed lung; and
in an epidemic described by Kiihn, search for
micro-organisms gave a negative result.
PYAEMIA IN RABBITS, Koch. — After failing to
produce a general infection in rabbits by the
injection of putrid blood, Koch succeeded with a
fluid obtained by macerating for two days in dis-
tilled water a bit of the skin of a mouse. The
animal died at the end of one hundred and five
hours, and a purulent infiltration of the subcuta-
neous cellular tissue was found, extending from
the point of inoculation as far as the hip behind,
and to the middle of the belly below. The peri-
toneal cavity contained a turbid fluid, and its
walls were covered in places by white patches.
The liver was covered with a fibrinous exudation,
and presented a grayish mottled appearance ; upon
section it showed gray, wedge-shaped patches. In
the lungs were found dark red patches, the size of
a pea.
344 BACTERIA IN INFECTIOUS DISEASES.
A syringeful of blood from thte animal killed a
second rabbit in forty hours. Rabbit No. 3 was
killed in fifty-four hours by three drops of blood
from No. 2 ; one drop from No. 3 killed No. 4 in
ninety-two hours; one-tenth of a drop from No.
4 killed No. 5 in one hundred and twenty-five
hours. The pathological appearances in this se-
ries of rabbits were similar to those noted in
the first, viz. : —
" Local purulent cedematous infiltration of the sub-
cutaneous cellular tissue ; metastatic deposits in the
lungs and liver ; swelling of the spleen and peritonitis.
These appearances harmonize so closely with those
commonly designated as pyaemia that I do not hesitate
to use that term for the disease under consideration.
" On microscopic examination micrococci are found
in great numbers everywhere throughout the body, and
more especially in parts which have undergone altera-
tions visible to the naked eye. These micrococci are,
for the most part, single or in pairs, and their meas-
urement is therefore difficult. Ten measurements of
pairs of micrococci differed but little from each other,
and gave .25 /JL. as the average diameter of a single
individual."
It will be noticed that this is much less than the
size of the oval micrococcus which produces septi-
caemia in rabbits.
"As regards size, therefore, they stand midway
between the chain-like micrococcus of the progressive
gangrene of the tissues and the zoogloea-forming micro-
coccus of the cheesy abscesses of rabbits. Their relation
to the blood-vessels can be best seen in the renal capil-
PYAEMIA IN RABBITS.
345
Fig. 18.
laries, and I have
therefore selected a
small vessel from the
cortex of the kidney
for delineation (Fig.
18)
" In the interior of
the vessel, at c, is a
dense deposit of mi-
crococci adherent to
the wall, and enclos-
ing in its substance
a number of red blood-
corpuscles. This mass
would probably have very soon filled the calibre of the
vessel ; for fresh corpuscles are constantly being de-
posited upon it, and these become surrounded by deli-
cate offshoots from the mass of micrococci. From this
we may conclude, either that the micrococci have of
themselves, owing to the nature of their surface, the
power of causing the red blood-corpuscles, to which
they adhere, to stick together, or that these organisms
can occasion coagulation of the blood in their vicinity,
and thus the formation of thrombi. . . .
" Such partial or complete thrombus formations oc-
cur in the renal vessels in many places, particularly in
the glomeruli, where individual capillary loops may
be found completely blocked by micrococci. ... In the
larger vessels, also, groups of considerable size are
formed, and I am disposed to believe that the large
metastatic deposits in the liver and in the lungs do not
arise by gradual growth of a mass of micrococci, but by
the arrest of large groups of micrococci and of clots
associated with them, formed in the manner described,
346 BACTERIA IN INFECTIOUS DISEASES.
iii the circulating blood ; in other words, by true em-
bolism." *
RELAPSING FEVER. — The presence in the blood
of patients suffering from relapsing fever of a
parasitic micro-organism, of spiral form, and ex-
hibiting active movements, was discovered by
Obermeier in 1868. Since this date numerous ob-
servers have confirmed the discovery, and have
verified the fact that this parasite is uniformly
found in the blood, in this disease, when the fever
is at its acme, both during the first invasion and
the relapse. It disappears very quickly, how-
ever, when defervescence occurs. These spiral
filaments (see Fig. 3, Plate VII.) are extremely
slender, the diameter never exceeding 1 p.. Their
length is from 150 to 200 p..
" Their motion is very lively, rotatory, twisting, and
rapidly progressive; but soon ceases under the ordinary
conditions of microscopic examination. As the blood
under examination cools and begins to coagulate, these
movements become slower, and many spiral filaments
become covered with very fine threads of fibrine "
(Lebert).
Inoculation of monkeys with the blood of re-
lapsing fever-patients has been successfully prac-
tised by Koch and by Carter. Both of these
experimenters have also succeeded in cultivating
the spirochaete external to the living body.
1 Traumatic Infective Diseases, Sydenham Society's translation, p. 61.
RELAPSING FEVER. 347
As the result of numerous experiments upon
monkeys, Carter arrives at the following con-
clusions : —
"1. The spirillum fever (relapsing fever) of man is
directly transmissible to a quadrumanous animal. 2.
There occurs a non-febrile infection of the blood prior
to 4 fever.' 3. Though the blood-spirillum was never
seen in the monkey without fever ensuing sooner or
later, yet the p^yrexia is secondary in time, and is sus-
ceptible of highly varied manifestations ; and the spir-
illum-disease might be denned as essentially a mycosis
sanguinis cum febre."
MotschutkofFsky has performed inoculation ex-
periments upon man, and was successful with blood
taken during the pyrexia; while apyretic blood,
milk, urine, etc., gave negative results. Accord-
ing to Heidenreich, " The addition of equal parts
of water to the blood is fatal to the spirochaete.
Its activity is not affected by any internal admin-
istration of quinine, salicylate of soda, or other
agents, and externally only affected by about one
per cent of quinine." l
The evidence in favor of the essential etiological
relation of Spirochcete Obermeieri to the form of
fever with which it is associated is very strong,
independently of the confirmatory experimental
evidence.
We have here a peculiar parasite invading the
blood in very great numbers during the access of
1 Quoted from Shattuck, in Supplement to Ziernssen's Cyclopaedia.
348 BACTERIA IN INFECTIOUS DISEASES.
the fever; the uniform presence of which, during
the first invasion and the relapses, has been verified
by numerous observers in various parts of the
world. Inasmuch as the blood of healthy persons
is free from bacterial organisms of any kind, and
as this peculiar organism is not found in any other
febrile affection, the presumption is altogether in
favor of its causal relation. Looking at it from
another point of view, it is difficult to believe that
the vital fluid could be invaded by myriads of
active parasitic organisms, which must appropriate
to their own use material required to preserve the
integrity of the circulating fluid and for the nu-
trition of the tissues, without some disturbance
of the economy resulting. In other words, we can
easily understand that the presence of the spiro-
chsete might give rise to the fever and other phe-
nomena of the disease ; but there is nothing in
our experience to indicate that fever causes the
appearance in the blood of parasitic organisms of
this description.
The evidence in this case is very different from
that relating to the presence of micro-organisms
in morbid products of a low grade of vitality found
during life, or the demonstration post mortem of
similar organisms in the blood or tissues. And
while we may demand, as final proof, that the dis-
ease shall be produced by inoculation with a " pure
culture" of the parasite, yet, in the absence of
such demonstration, it must be admitted that the
evidence is very convincing as to the causal re-
SCARLET FEVER. 349
lation of Spirochcete Obermeieri to the disease in
question.
SCARLET FEVER. — " Coze and Feltz have found
in the blood of scarlet fever, taken from patients,
living or recently dead, some rods as well as mo-
bile points. This blood injected into the cellular
tissue of rabbits has sometimes produced death,
and the blood of the animals experimented upon
has presented the same bacteria as human blood
of scarlatina : they are simply a little larger and
longer. As to the mobile points, they appear to
correspond to the micrococcus of scarlatina de-
scribed by Hallier" (Magnin). Reiss found, in
blood drawn from a vein in the arm of a patient
dying of scarlet fever, that " the serum was filled
with an infinite number of small, rapidly oscillating
bodies, which, under a magnifying power of five
hundred diameters, appeared as black points be-
tween the groups of blood corpuscles. In addition,
there were also rod-like formations, which at many
places were recognized as being composed of three
or four or more of these minute bodies disposed in
rows." Reiss injected a few drops of this blood
under the skin of the back of a rabbit, with the
effect of developing like small bodies in its blood,
and causing death in twenty-four hours. Further
inoculations with this rabbit's blood gave rise to
identical results.1 In the experiments of Coze
and Feltz, the introduction of a small quantity of
1 Thomas in Ziemssen's Cyclopaedia.
350 BACTERIA IN INFECTIOUS DISEASES.
scarlatinous blood beneath the skin of rabbits
proved fatal to sixty-two out of sixty-six animals
experimented upon. (Query: Was this blood
obtained post mortem, or during the life of the
patients ?)
The evidence that the rabbits, in the experi-
ments referred to, suffered a genuine attack of
scarlet fever, is not satisfactory ; and it must be
remembered, in estimating the scientific value of
such experiments, that rabbits are very subject to
infectious forms of septicaemia ; and that the blood
of man and animals, obtained post mortem from a
variety of acute febrile diseases, will produce sim-
ilar results. On the other hand, it must be ad-
mitted that, in its short period of incubation and
in other particulars, malignant scarlet fever resem-
bles the infectious forms of septicaemia in the
lower animals, shortly to be described ; and that
septicaemia in man is sometimes attended with a
scarlet eruption resembling exactly that which
characterizes the disease under consideration.
The occurrence of disease, supposed to be iden-
tical with scarlet fever in man, among the domes-
tic animals, — horses, dogs, cats, swine, — has been
noted by several observers ; and in certain cases
communication of the disease by contagion has
been traced. " Thus Heim observed that a dog
which had lain in the same bed with a scarlatinous
child, was taken with fever; followed by scarla-
tina and desquamation." l
1 Thomas in Ziemasen's Cyclopaedia.
SEPTICAEMIA IN MICE. 351
The resources of modern science have not yet
been fairly brought to bear for the elucidation of
the etiology of this pestilential disease, which in
all countries contributes so large a share to the
mortality among young children; and it is to be
hoped that some government, more liberal in this
direction than is that of the United States, may
undertake a thorough experimental investigation,
in the interests of its citizens, if the advancement
of science per se is not a sufficient motive. The
unsatisfactory results heretofore attained are doubt-
less to be ascribed to the fact that the difficulties
connected with the solution of the problem are
too great to be met by individual enterprise, and
also to the fact that no amount of enthusiasm can
take the place of skill and experience in investiga-
tions of this nature. Enough has been done to
show that the persistent efforts of trained experts,
supported by liberal government patronage, will
be required for the settlement of the more difficult
problems in etiology.
SEPTICAEMIA IN MICE, Koch. — Koch at first
failed to produce an infectious disease in mice by
the subcutaneous injection of putrid fluids, — blood,
meat infusion, etc., — although the injection of a
sufficient quantity of these fluids produced death
in a few hours. Thus five drops of putrid blood
caused the death of a mouse in four to eight hours,
and the symptoms of poisoning were developed
immediately. But no bacteria were found in blood
352 BACTERIA IN INFECTIOUS DISEASES.
taken from the heart, or in the internal organs of
a mouse killed by such an injection ; nor did its
blood, taken from the right auricle, cause the death
of other mice into which it was injected. The
symptoms of poisoning in these cases were more
or less severe according to the amount of septic
material introduced, and no doubt were due to the
chemical poison, sepsin, which is present in putrid
blood. But when small quantities of this putrid
blood were injected, it happened that, while a
majority of the little animals experienced no per-
ceptible effects from the injection, a certain num-
ber fell ill at the end of twenty-four hours, and
death occurred in forty to sixty hours from the
time of inoculation.-
In these cases the symptoms and post mortem
appearances were of a definite character, and the
disease was proved to be infectious. This was
shown by inoculation from mouse to mouse of a
minute quantity of blood, — one-tenth of a drop
was ample. Koch says : " I have performed these
experiments on fifty-four mice, and have always
obtained the same result. Of these, seventeen
inoculations were made in succession." 1 We must
refer the reader to Koch's work for the symp-
toms and pathological appearances which charac-
terize this infectious disease ; its etiology alone
concerns us here.
The certainty with which the infective material
can be carried from one animal to another is said
1 Traumatic Infective Diseases.
SEPTIC^MIA IN MICE.
353
to be even greater than in anthrax. In order to
infallibly bring about the death of one of these
little animals within the time stated, — about fifty
hours, — it is sufficient to pass the point of a
scalpel, which has been in contact with the in-
fected blood, over a small wound in the skin.
Koch suspected that this great virulence was
due to the abundant presence of a micro-organism
in the infectious material,
but failed in his earlier ef-
forts to find this parasite in
septiccemic blood. This was
found, later, to be owing to
the minute size of the ba-
cilli to which the disease is
ascribed ; and by the use of
Abbe's condenser he was
able to demonstrate the
presence in large numbers
of the bacilli seen in Fig. 19,
which is copied from his work (I. c.).
"The bacilli lie singly or in small groups between the
red blood corpuscles, and have a length of .8 to 1 p.
Their thickness, which cannot be measured accurately,
but only approximately estimated, is about .1 to .2 //,.
. . . One often sees the bacilli in septiesemic blood
attached to each other in pairs, either in straight lines
or forming an obtuse angle. Chains of three or four
bacilli also occur, but they are rare. . . . Without the
use of staining materials, the bacilli can only with
extreme difficulty be recognized in fresh blood, even
when one is familiar with their form ; and I have not
23
Fig. 19.
White blood-corpuscles from one
of the veins of the diaphragm of
a septicaemic mouse. X 700.
354 BACTERIA IN INFECTIOUS DISEASES.
been able to obtain any certain evidence as to whether
they move or not. Their relation to the white blood
corpuscles is peculiar. They penetrate these, and mul-
tiply in their interior. One often finds that there is
hardly a single white corpuscle in the interior of which
bacilli cannot be seen. Many corpuscles contain isolated
bacilli only ; others have thick masses in their interior,
the nucleus being still recognizable ; while in others the
nucleus can be no longer distinguished ; and finally
the corpuscle may become a cluster of bacilli, breaking
up at the margin, — the origin of which one could not
have explained had there been no opportunity of seeing
all the intermediate steps between the intact white
corpuscle and these masses (Fig. 19). Starting from
the point of inoculation, one can easily see the path by
which the bacilli have penetrated into the body. In the
subcutaneous cellular tissue in the neighborhood of the
inoculated spot they are very numerous, and at times
accumulated in dense masses, as can be best observed
in inoculations on the ear. ... I have never found
these bacilli in the lymphatic vessels. ... I have not
found them free in the cavities of the body. ... In
the capillaries the bacilli congregate, particularly at the
points of division ; but I have never yet seen a complete
obstruction of the smaller vessels produced in this way.
... In exactly the same manner are the bacilli dis-
tributed in the rest of the vascular system. In the ex-
amination of sections of lung, liver, kidney, and spleen,
one meets everywhere with vessels containing free
bacilli, and with white blood corpuscles with bacilli in
their interior. . . . The whole morbid process has thus
a great resemblance to anthrax. In both diseases the
infective power of the blood is due to the bacilli present
in it ; as soon as these disappear, the disease can be no
longer produced by inoculation with the blood. Both
SEPTICAEMIA IN RABBITS. 355
diseases are distinguished by the invariable develop-
ment of exceedingly numerous bacilli. There can thus
be no doubt that the bacilli of the septicsemia described
here possess the same significance as the bacilli of
splenic fever, namely, that they are to be regarded as
the contagium of this disease."
Very interesting are the results obtained by
Kocb in his attempts to infect other animals with
the blood of septicsemic mice. The rabbit, so sus-
ceptible to anthrax and to other forms of septicae-
mia, resisted not only inoculations with small
amounts of the virulent blood, but the entire
amount of blood from a septicsemic mouse failed to
produce any effect. Field mice, also, although so
closely resembling house mice, upon which the
successful experiments were made, proved not to
be susceptible to the disease.
SEPTICAEMIA IN RABBITS. — The writer discov-
ered accidentally, in September, 1880, the virulent
properties of his own saliva when injected into
rabbits, and has since demonstrated the fact that
the highly infectious disease which results from
such an inoculation is due to a micrococcus con-
stantly present in the buccal secretions, — i. e., in
the mixed secretions as found in the mouth.
The experiment which led to this discovery was
made as a check upon other inoculation experi-
ments, with a view to ascertain whether a fluid
supposed to be innocuous would produce any no-
ticeable febrile disturbance when injected beneath
356 BACTERIA IN INFECTIOUS DISEASES.
the skin of a rabbit. The unexpected death of the
animal led to a repetition of the experiment, with
the same result, except when the animal experimented
upon had previously been inoculated with various fluids
containing bacteria. These exceptions will be re-
ferred to later.
The question at once arose in the writer's mind
as to whether the virulence of his saliva, as shown
by, these experiments, was an individual pecu-
liarity, due perhaps to some antecedent event in
his personal history, — e. g., an attack of yellow
fever experienced in 1875 ; or whether it was due
to circumstances relating to his environment at
the time, — e. g.? residence in a Southern city dur-
ing the summer months, and constant contact with
putrefying organic material in the course of his
experimental studies ; or whether it was, possibly,'
a general fact that human saliva is fatal to rabbits,
when injected beneath their skin.
These questions could evidently only be settled
by the experimental method, and a visit was made
to the city of Philadelphia, during the month of
January, 1881, for the purpose of pursuing the
investigation, with the kind assistance of Dr.
Formad, in the laboratory of the Medical Depart-
ment of the University of Pennsylvania, Here,
eleven inoculation experiments demonstrated
(a) that the virulence noted was not due to sea-
son or to locality, — as the same result followed
inoculations made in Philadelphia during the win-
ter months as had been obtained by similar in-
SEPTICAEMIA IN RABBITS. 357
oculations in New Orleans during the heat of
summer ; (#) that this virulence was not an indi-
vidual peculiarity, inasmuch as eleven rabbits,
inoculated with the saliva of six different persons,
gave eight deaths and three negative results. As
no account was made of the previous history of
these rabbits, it is now impossible to say whether
these negative results are to be ascribed to a less
degree of virulence of the saliva injected, or to
antecedent experimental injections which had pos-
sibly been made in the laboratory, and which
afforded these animals protection. Still, a differ-
ence in the degree of virulence was shown by the
fact that in these, and in numerous subsequent
experiments, the writer's saliva has never failed to
kill unprotected rabbits within forty-eight, or at most
sixty hours ; while in a considerable number of
experiments with the saliva of other persons, there
have been several failures to kill ; and in other
cases the fatal result has been delayed to three or
four days, and even longer. This difference could
not be accounted for as being connected with un-
sound teeth or the use of tobacco. The writer
has sound teeth, and the secretions which accumu-
late in his mouth are normal in appearance and
reaction, and free from any odor.
The facts thus far observed seemed to be
worthy of fuller investigation, with a view to
explaining the cause of this virulence ; and in the
month of March further experiments were com-
menced in the biological laboratory of Johns Hop-
358 BACTERIA' IN INFECTIOUS DISEASES.
kins University. The result of these was very
definite, and experimental proof was obtained that
the fatal result is due to the presence of a micro-
coccus in the saliva, which finds the conditions
favorable for its rapid multiplication when intro-
duced beneath the skin of a rabbit, and which
gives rise to an infectious form of septicaemia, in
which, owing to its presence in the blood of an
animal recently dead, a minimum quantity of
blood taken from the heart of a victim to the
disease, is infallibly fatal to other rabbits when
introduced in like manner into the subcutaneous
cellular tissue. The evidence in support of the
etiological role of the micrococcus in this induced
septicaemia of the rabbit is of the same nature as
that, just recorded, in the form of septicaemia of
the mouse studied by Koch, and as that by which
the anthrax bacillus has been shown to be the
cause of anthrax. It may be summarized as
follows : —
(a) The poison is proved to be participate by filtration
experiments.
(6) The virulent fluids, saliva, blood, culture-fluids,
all contain a micrococcus. (See Figs. 1 and 3,
Plate VI.)
(c) These fluids produce an identical result, and this
result does not vary according to the quantity of mate-
rial introduced, as is the case where poisonous proper-
ties depend upon the presence of a chemical poison.
(d) Those agents which destroy the vitality of the
micrococcus destroy the virulence of the fluids contain-
ing it.
SEPTICAEMIA IX RABBITS. 359
(e) Pure cultures of the micrococcus are as virulent as
the saliva, in the first instance, or the blood of a rabbit
killed by introducing this fluid beneath its skm.
I have usually injected from 5 to 20 minims
of saliva (mixed salivary secretions and buccal
mucus as found in the mouth), and, as stated in
my first report, this has infallibly proved fatal (to
unprotected animals). But in an experiment made
in Baltimore, a single minim of saliva mixed with
five minims of distilled water was injected into each
of five young rabbits. Three of the five died within
the usual time — forty-eight hours — with the usual
symptoms, and presenting the characteristic patho-
logical appearances. The other two showed no ill
effect from the injection.
The following quotation from my first report
shows the character of this fatal infectious disease,
which, originating, as in the above-mentioned ex-
periment, from the introduction of a single drop of
human saliva beneath the skin of one of these ani-
mals, may be transmitted indefinitely from one to
'another by successive inoculations.
"The course of the disease and the post mortem
appearances indicate that it is a form of septicaemia.
Immediately after the injection there is a rise of tem-
perature, which in a few hours may reach 2° to 3° C.
(3.6° to 5.4° Fahr.) ; the temperature subsequently
falls, and shortly before death is often several degrees
below the normal. There is loss of appetite and marked
debility after twenty-four hours, and the animal com-
monly dies during the second night or early in the morn-
360 BACTERIA IN INFECTIOUS DISEASES.
ing of the second day after the injection. Death results
still more quickly when the blood from a rabbit recently
dead is injected. Not infrequently convulsions imme-
diately precede death.
"The most marked pathological appearance is a diffuse
inflammatory oedema or cellulitis, extending in all direc-
tions from the point of injection, but especially to the
dependent portions of the body. Occasionally there is
a little pus near the puncture, but usually death occurs
before the cellulitis reaches the point of producing pus.
The subcutaneous connective tissue contains a quantity
of bloody serum, which possesses virulent properties,
and which contains a multitude of micrococci. . There
is usually more or less inflammatory adhesion of the
integument to the subjacent tissues. The liver is some-'
times dark colored and gorged with blood, but more
frequently is of a lighter color than normal, and contains
much fat. The spleen is either normal in appearance or
enlarged and dark colored. Changes in this organ are
more marked in those cases which are of the longest
duration. In certain cases dark-colored pigment has
been found in the spleen, resembling that which has
been supposed to be characteristic of malarial fever.
The blood is dark-colored, usually fluid, and there is a
tendency to agglutination of the red corpuscles.
"The blood commonly contains an immense number of
micrococci, usually joined in pairs, and having a diam-
eter of about 0.5 //,. These are found in blood drawn
from superficial veins, from arteries, and from the cavi-
ties of the heart immediately after death, and in a few
cases their presence has been verified during life. Ob-
servations thus far ma'le indicate, however, that it is
only during the last hours of life that these parasites
multiply in the circulating fluid, and in a certain pro-
portion of the cases a careful search has failed to reveal
SEPTICAEMIA IN RABBITS. 361
their presence in post mortem examinations made imme-
diately upon the death of the animal. This organism,
however, is invariably found in great abundance in the
serum which exudes in considerable quantities from
the cedematous connective tissue when an incision is
made through the integument over any point involved
in the inflammatory oedema extending from the original
puncture."
In this, as in other infectious diseases, the final
proof that micro-organisms present in infective
material are the cause of the train of morbid phe-
nomena constituting the disease, is to be obtained
only from inoculation experiments with pure cul-
tures of these micro-organisms. This proof was
obtained for the disease in question during my
Baltimore experiments (1881), and a repetition of
these experiments in San Francisco (1882) has
fully confirmed the results first reported, as is
shown by the following record of experiments : —
"Exp. No. 1. — San Francisco, July 6, 1882. In-
jected twenty-five minims of my own saliva beneath
the skin of left flank of each of two half-grown rabbits.
Result. — Both rabbits were found dead on the morning
of July 8. Post mortem examination at 8 A. M. showed
extensive cellulitis, dilatation of superficial veins, and
abundant effusion of serum in subcutaneous connec-
tive tissue. This serum and the blood obtained from
the heart, swarmed with micrococci exactly resembling
those heretofore found under similar circumstances in
New Orleans, Philadelphia, and Baltimore.1 One rab-
1 See Special Report to Nat. Board of Health in Bulletin N. B. of H.
April 30, 1881.
362 BACTERIA IN INFECTIOUS DISEASES.
bit was still warm, the other had evidently been dead
for several hours. The spleen of the first was but
slightly enlarged, that of the second was swollen, hard,
and dark-colored in patches. No pigment found in
either spleen.
" A culture-flask containing sterilized rabbit bouillon
was inoculated with blood from the heart of rabbit No.
1. At the end of twenty-four hours the fluid in this
flask swarmed with micrococci. A second culture-flask
was inoculated from this, a third from the second, and
so on to the sixth, twenty-four hours being allowed in
each case for the development of the micrococcus.
[The flasks were placed in a culture-oven maintained at
a temperature of 100° Fahr. For the author's method
of manipulation see p. 177.]
44 Exp. No. 2. — July 15. Injected twenty-five min-
ims of above culture-fluid (sixth) beneath the skin of
a half-grown rabbit. Result. — This rabbit died during
the night of July 18, and upon post mortem examination
was found to present the same pathological appearances
as in the former experiment, — viz., extensive cellu-
litis, with effusion of serum swarming with micrococci.
The blood also contained the micrococci in abundance ;
spleen somewhat enlarged and dark-colored ; no pig-
ment found.
44 A new culture was started from the blood of this
rabbit by introducing a minute quantity of blood di-
rectly from the left auricle into a culture-flask contain-
ing sterilized rabbit bouillon. As before, this was carried
by successive inoculations from one flask to another to
the sixth culture, the culture-flask being in each in-
stance placed in an oven at 100° Fahr., for twenty-four
hours, for the development of the micrococcus.
44 Exp. No. 3. — July 26. Ten minims of above-cul-
ture (No. 6) was injected beneath the skin of a half-
SEPTICAEMIA IN RABBITS. 363
grown rabbit. Result. — The animal died at 10 A. M.,
July 29, and a post-mortem examination was made at
once. The subcutaneous cellular tissue was, as usual,
infiltrated with serum containing the micrococcus,
which was also present in the blood in large numbers.
The spleen was very large and dark-colored. A por-
tion was removed for microscopical examination, and
the remainder left in situ, the animal being so placed
that it should be dependent. No pigment was found
in the portion first removed, but the presence of black
pigment in the portion left in situ was verified the fol-
lowing day (removed at 9 A. M.).
44 The culture-fluid (No. 6) used in experiment No. 3
(July 26) was laid aside in an hermetically sealed
culture-flask until September 12, when a minute drop
was used to inoculate sterilized bouillon in culture-tube
No. 7. This, placed in a culture-oven at 100° Fahr. for
twenty-four hours, became clouded, and upon micro-
scopical examination proved to be pervaded by the
identical micrococcus heretofore described and photo-
graphed. A drop of culture No. 7 was used to inocu-
late culture No. 8, and the next day, this, being also
pervaded by the micrococcus, was used in the following
experiment : —
44 Exp. No. 4. — September 14. Injected ten minims
of culture No. 8 into a full-grown rabbit. Result. —
This animal died at 9 A. M., September 15, and a micro-
scopical examination made at once demonstrated the
presence of the micrococcus in great numbers in the
blood and in effused serum in the subcutaneous con-
nective tissue. The usual diffuse cellulitis, extending
from the point of inoculation, was present; spleen
small, and contained no pigment.
44 Remarks. — This experiment shows that the micro-
coccus retained its vitality and its full virulence at the
364 BACTERIA IN INFECTIOUS DISEASES.
end of six weeks ; and, very conclusively, that the viru-
lence of the culture-fluid is due to the presence in it of
the micrococcus, and not to a hypothetical chemical
virus found in the first instance in the saliva, and sub-
sequently in the blood of a rabbit inoculated with this
fluid. For the benefit of those who have not calculated
the degree of dilution which such a hypothetical chemi-
cal virus would undergo in such a series of culture
experiments, I submit the following simple calculation :
My culture-tubes contain about a fluidrachm of steril-
ized bouillon. The amount of blood introduced into
culture No. 1, as seed, was considerably less than a
minim, but for convenience I will suppose that one
minim is used each time to start a new culture, — that
is, the original material is diluted 60 times in the first
culture, 3600 times in the second, 216,000 times in the
third, and in the eighth culture it will be present in the
proportion of one part in 167,961,600,000,000. Yet a
few minims of this eighth culture possess all the viru-
lence of the first. . . .
41 To convince those who still question the etiological
role of the micrococcus in the infectious disease of rabbits
at present under consideration, it would hardly be worth
while to carry our culture experiments further, as has
been done by Pasteur and other pioneers in this field of
investigation, — e. g., in anthrax and in fowl-cholera. I
therefore turn to another line of proof.
44 1 have fixed very definitely the thermal death-point
of this septic micrococcus. It is killed by exposure for
ten minutes to a temperature of 140° Fahr. It survives
exposure to 130° for the same time. This is the result
of a considerable number of experiments, and is estab-
lished by the simple method of exposing a culture-fluid
containing the micrococcus, and enclosed in a hermeti-
cally-sealed tube, to a given temperature for the time
SEPTICAEMIA IN RABBITS. 365
adopted as a standard, — ten minutes, — and then using
the fluid to inoculate sterilized bouillon in another tube.
This, being placed in a culture oven for twenty-four
hours, remains transparent and unchanged if the seed
has been killed, but is clouded and pervaded by the
micrococcus if its vitality was not destroyed.
" In my first series of experiments (Baltimore, 1881)
I found that boiling destroys the virulence of blood from
a septicsemic rabbit. Having now fixed with precision
the thermal death-point of the micrococcus, the next step
was evidently to see whether this temperature also
destroys the virulence of the fluid containing it. To
test this matter, the following experiment was made
with the second culture from the blood of the rabbit
which died September 15, as above reported.
" Exp. No. 5, September 17. — Injected ten minims
of culture No. 2 beneath the skin of a small spotted
rabbit, also ten minims of the same culture-fluid, heated
to 140° Fahr. for ten minutes, beneath the skin of a
small white rabbit of the same litter. Result. — The
small spotted rabbit was found to be dying the follow-
ing morning at eight o'clock. It was killed bv breaking
up the medulla, and the blood from the heart examined
immediately. This contained the micrococcus in abun-
dance, as did also a quantity of serum contained in the
pleural cavity and effused serum in the subcutaneous
cellular tissue. The small white rabbit, injected at the
same time with the same culture-fluid, heated to 140° for
ten minutes, did not seem to experience the slightest ill
effect from the injection, and to-day (September 24)
remains in apparent good health ; that is, the virulence
of the culture-fluid used in this experiment was destroyed
by the exact temperature which I had previously determined
to be fatal to the micrococcus." 1
1 Quoted from communications to the " Philadelphia Medical Times/'
of September 9 and November 4, 1882.
366 BACTERIA IN INFECTIOUS DISEASES.
If further proof is required, it is to be found
in the comparison which the writer has made
in his paper on the " Germicide Value of Certain
Therapeutic Agents," l of the action of germicides
upon the micrococcus as contained in culture-fluids,
as compared with the power of the same agents
to destroy the virulence of septic blood, as tested
by inoculation experiments (/. c. p. 342).
It is worthy of remark that, in the very numer-
ous culture-experiments made by. the writer at
different times and places, in which a sterilized
culture-fluid has been inoculated with a minute
quantity of blood from the heart of a rabbit just
dead from the form of septicaemia under consider-
ation, or from a vein, or from effused serum in the
cellular tissue, the micrococcus already described
has always been found in the culture after twenty-
four hours' incubation, and it has invariably been found
alone, no other micro-organism having been associ-
ated with it in any case. This is offered as very
satisfactory proof of the reliability of the method
adopted, — i. e., as regards the possibility of acci-
dental contamination ; and of the constant presence
of this particular micrococcus in the fluids men-
tioned.
Shortly before the publication of the writer's
first report relating to this form of septicaemia in
the rabbit, Pasteur announced to the French Acad-
emy his discovery of a " new disease " resulting
1 American Journal of the Medical Sciences, No. CLXX., April,
1 b s j .
SEPTICAEMIA IN RABBITS. 367
from the injection beneath the skin of a rabbit of
buccal mucus, gathered by means of a camels-
hair brush from the mouth of a child which died
in one of the hospitals of Paris from hydrophobia
(December 11, 1880). The material was obtained
four hours after death; the brush used to collect it
was washed out in water, and the fluid injected
into two rabbits. These were found dead Decem-
ber 13. Other rabbits were inoculated with blood
from these, and their death with the same symp-
toms proved that an infectious disease had been
produced.
There can no longer be any doubt that this dis-
ease was identical with that which the writer had
previously produced by inoculating rabbits with
his own saliva ; and, consequently, that the natural
inference of Pasteur that this " new disease " was
due to the fact that the child from whom the
material which produced it was obtained had died
of hydrophobia, was an error. Subsequent experi-
ments by Yulpian and others soon made it plain
that a mistake had occurred, and nothing more has
been heard from Pasteur concerning his new dis-
ease. But the results reported are entirely in
accord with the deductions of the writer as to the
etiological role of the micrococcus.
Pasteur describes this as follows : —
"This organism is sometimes so small that it may
escape a superficial observation. Its form does not differ
from that of many other microscopic beings. It is an
extremely short rod a little compressed towards the
368 BACTERIA IN INFECTIOUS DISEASES
middle, resembling a figure 8, and of which the diameter
of each half often does not exceed a half a thousandth
of a millimeter. Each of these little particles is sur-
rounded at a certain focus with a sort of aureole which
corresponds, perhaps, to a material substance."
The possibility that this appearance is due to
diffraction is considered, but Pasteur inclines to
the opinion that in the case in question it is due
to a mucous substance which surrounds the organ-
ism. (See Fig. 3, Plate VI.)
At the meeting of the French Association for
the Advancement of Science, in 1881, Chauveau,
in his address as President of the Association,
says : " For a moment we hoped that Pasteur
had determined thus [by artificial cultivation] the
virus of hydrophobia, but he tells us himself that he
has only cultivated a new septic agent" Koch's recent
attack upon Pasteur, in which he makes much of
this mistake, seems a little out of place in view of
this frank confession made more than two years
ago.
The last-named observer has also encountered
this form of induced septicaemia in the rabbit, and
has shown that the micrococcus which produces it
is not alone found in human saliva. This was a
priori to have been expected, and the writer has
never supposed that the human mouth was the
only habitat of the micro-organism in question.
But being unwilling to generalize from insufficient
data, he has not even claimed that all human saliva
is fatal to rabbits, but has taken pains to say, in
SEPTICAEMIA IN RABBITS. 369
recording his results, "my saliva/' injected in such
or such an amount, produces, etc.
Koch gives the following account of the occur-
rence of this interesting disease in the course of
his experimental inoculations: —
44 After injection of putrid infusion of meat into
rabbits, I have twice obtained a general infection of
another sort in which metastatic deposits do not occur
[as is the case in the disease described by him as pyaemia
in rabbits], and which I would therefore describe, in
contrast to the foregoing, as septicaemia. This infusion,
like the putrid fluids used in the earlier experiments,
contained numbers of bacteria of the most various forms.
When injected under the skin of the back of a rabbit it
produces an extensive putrid suppuration of the sub-
cutaneous cellular tissue, and the animal dies in three
da}'s and a half. At the ichorous spot, which must, on
account of its size, be looked upon as the immediate
cause of death (owing to absorption of poisonous material
in solution), the same variety of bacteric forms was
present as in meat infusion. At the border of this spot
the cellular tissue was infiltrated with a slightly turbid
watery fluid which contrasted strikingly with the brown-
ish ichor in the vicinity of the place of injection. In
this oedema fluid great numbers of micrococci of con-
siderable size and of an oval form were almost the only
organism observed. In the blood also similar micrococci
were found, though only in small numbers. Further,
in the papilli of the kidney and in the greatly enlarged
spleen, some of the small veins were blocked for short
distances with these oval micrococci.
4' Two drops of this oedematous fluid were now in-
jected under the skin of the back of a second rabbit.
The animal died in twenty-four hours, and here, in the
24
370 BACTERIA IN INFECTIOUS DISEASES.
neighborhood of the place of injection, not a trace of
pus could be observed. On the other hand, slight oedema,
with a streaky whitish appearance of the subcutaneous
cellular tissue, extended from the point of injection to
the abdomen. I,n this cedematous cellular tissue lay
numerous flat extravasations of blood half a centimeter
in breadth, the vessels around being greatly distended.
The muscles of the thigh and of the abdominal walls
were also interspersed with small extravasations. [These
hemorrhagic extravasations were common also in the
victims of the writer's experiments.] In the heart and
lungs no alterations were found. In the peritoneal
cavity no fluid was present, the peritoneum being un-
altered and the coils of intestine not glued together.
But the surface of the intestine, in consequence of a
number of small subserous extravasations, presented an
appearance as if injected here and there with blood.
The spleen was also very considerably enlarged. In
this second animal the oval micrococci were alone present
in the cedematous cellular tissue, all the other bacteria
having disappeared. The number of these organisms
was very considerable, many of the small veins being
completely filled with them. . . .
44 These micrococci differ from the micrococci of
pyaemia very markedly as regards size, and in most
other points. Thus they never enclose the blood cor-
puscles, even when they have accumulated in large
numbers in the interior of the blood-vessels. They
rather push them on one side. They do not cause co-
agulation of the blood, and thus emboli do not occur."
The experiments made by the writer have been
repeated by Claxton, who says : —
" I shall now discuss briefly the second part of my
argument, namely, what constituent of the saliva pro-
SEPTIC JEMI A IN RABBITS. 371
duces the fatal disease ? And as my results accord so
perfectly with those obtained by Steinberg, and my ex-
periments in this direction are but repetitions of his, I
shall be pardoned, I trust, for answering the question in
his own words.
" 4 The following facts demonstrate that the phenomena
detailed result from the presence of a living organism
found in the saliva, namely, a micrococcus which multi-
plies in the subcutaneous connective tissue, and also in the
blood shortly before or after death.'' "
This extended account of the disease under con-
sideration, and of the evidence in support of the
writer's first announcement as regards its etiology,
has been given because rabbits are extensively
employed in experiments relating to the etiology
of infectious diseases, and it is important that
those who enter upon such investigations should
be familiar with all forms of disease to which they
are subject. And also, because, notwithstanding
the experimental evidence adduced in favor of the
view that the virulence of normal human saliva is
due to the micrococcus described, it has been evi-
dent that there has been considerable incredulity
as to the correctness of this conclusion, on the part
of many worthy members of the profession.
We have seen, in the article on septicaemia in
mice, that rabbits are not susceptible to this form
of septicaemia, which Koch has shown to be due
to a bacillus. On the other hand, Koch found
that the injection of blood from a septicaamic rab-
bit into a mouse, although it killed the little
372 BACTERIA IN INFECTIOUS DISEASES.
animal in thirty-seven hours, did not give rise to
the infectious form of the disease ; for a second
mouse, which was inoculated with blood from the
heart of the first, was not visibly affected.
In a limited number of experiments by the
writer, in which his own saliva was injected into
animals other than the rabbit, the following results
were obtained : —
Injection of 4 c. c. into each of two small dogs pro-
duced local abscesses at the point of injection, but no
other noticeable results. A dog succumbed, however,
to an injection of 1 c. c. of serum from the cellular tis-
sue of a rabbit recently dead.
Injection of 0.25 c. c. (each) into five chickens pro-
duced no result.
Injection of 0.75 c. c. (each) into three guinea-pigs
proved fatal to two, — one in three, and one in seven
days.
Injection of 0.5 c. c. into five rats resulted fatally to
one only.
These results correspond with those reported by
Pasteur, who found the guinea-pig less susceptible
than the rabbit ; the chicken entirely insuscepti-
ble ; and the dog susceptible to injections of blood
from dead rabbits.
The value of protective inoculations in this form
of septicaemia has been brought out accidentally
in the course of the writer's experiments ;. and it
li;i< been liis intention to investigate this interest-
ing subject fully by the experimental method.
This he has not yet been able to do, and, conse-
SEPTIC^IMIA IN RABBITS. 373
quently, can only present such facts as have been
developed by experiments made with a different
object.
Two rabbits injected with full doses of my
saliva, in New Orleans, proved to be insuscep-
tible to its lethal effects. These rabbits had
previously received the following experimental
inoculations : —
Rabbit No. 1. — Received October 7, 1.35 c. c. of
swamp-culture (organisms from swamp mud cultivated
in gelatine solution a la Klebs and Torumasi-Crudeli) ;
October 28, 1.3 c. c. of spleen-culture (from a rabbit
which died from an injection of 0.75 c. c. of swamp-
culture in gelatine solution).
Rabbit No. 2. — Received October 7, 1.35 c. c. of
spleen-culture ; and October 27, 1.26 c. c. of spleen-
culture, which injection was repeated the following
day.
On the 12th of November these rabbits both received
subcutaneously 1.26 c. c. of my saliva, and. except for a
slight febrile reaction, experienced no ill effect from the
dose.
Baltimore, May 24, 1881, injected into a large rabbit
1.25 c. c. of virus, not disinfected, from a rabbit recently
dead. Result negative. This rabbit had previously
(May 13) received an injection of 0.5 c. c. of virus
mixed half an hour previously with sodium hyposul-
phite in the proportion of one per cent. The virus
used in these experiments was bloody serum from a
rabbit just dead, which was proved by other experi-
ments to be fatal to unprotected rabbits in the smallest
quantity. Thus, the needle of a hypodermic syringe
(Exp. of June 2, 1881) was dipped into the blood of
374 BACTERIA IN INFECTIOUS DISEASES.
a septicaemic rabbit just dead, which was proved by
microscopical examination to contain the micrococcus
in abundance. This needle was then introduced under
the skin of another rabbit, which died within forty-
eight hours, and presented the usual appearances of
septicaemia.
Protection was also afforded in one case by an injec-
tion of virus which had been mixed half an hour
previously with 'three parts of 95 per cent, alcohol.
Finally, I take the liberty of quoting the case of Dr.
Formad's famous buck rabbit : —
" There remained in the laboratory a number of living
animals, left over after the various experimenters of my
pathological class ceased work, at the conclusion of last
winter's term. Among the number was a buck rabbit,
which had been largely dosed, by my friend Claxton,
with saliva of some kind. Since then, during the last
six months, this same rabbit was injected subcutane-
ously, at different times, with all the. articles of the
following bill of fare :
"1. Human saliva (second time); 2. Cancer juice;
3. Epidemic diphtheritic material from Michigan ;
4. Bouillon, containing a rich crop of cultured mi-
crococci from the same material ; 5. Diphtheritic ma-
terial from a fatal case in the city ; 6. Slough from
rabbit, dead from diphtheria ; 7. Slough from scarla-
tinal sore throat ; 8. Slough from erysipelas ; 9. Slough
from gangrene ; 10. Cadaveric poison ; 11. Feces from
typhoid fever case ; 12. Sputa from case of tuber-
culosis." i
It is pretty evident that this rabbit was pro-
tected from septic poisoning; and the case is ex-
i Philadelphia Med. Times, Sept. 16, 1882, p. 194.
SEPTIC^MIA IN RABBITS. 375
ceedingly instructive, not only as illustrating the
value of protective inoculations against septicae-
mia, but as showing the importance of selecting
rabbits not previously experimented upon for
experimental studies relating to the etiology of
infectious diseases.
It should also be remembered by those who
undertake experimental investigations of this na-
ture, that accidental inoculation may occur, or
that a rabbit may suffer a non-fatal attack as the
result of contact with other septicsemic animals, or
from being placed in infected cages. Davaine
long since recorded the fact that spontaneous
septicaemia occurred among his rabbits from this
cause ; and the writer has also lost a number of
rabbits in this way, while others of the same lot
recovered after a brief illness, and subsequently
proved to be protected from the lethal effects of
septic virus.
It is not impossible that, in man, a certain
immunity from infectious diseases, the epidemic
prevalence of which depends upon the presence
of decomposing organic material in the infected
localities, — e.g., cholera, yellow fever, diphtheria,
— may be acquired by exposure to septic material
which lacks the infectious character ; i. e., that a
tolerance is established to the effects of the chem-
ical poison or poisons which are evolved as a result
of the vital activity of both pathogenic and non-
pathogenic bacteria. It has frequently been noted
that grave-diggers, those who clean sewers, and
376 BACTERIA IN INFECTIOUS DISEASES.
those who pursue pathological studies, are even
less liable to contract the diseases mentioned than
those members of the community who are not so
much exposed to infection.
SPREADING ABSCESS IN RABBITS, Koch : —
" Coze and Feltz, Davaine, and many others, have
obtained in rabbits, by the injection of putrid blood, an
infective septicaemic disease. I have therefore repeated
their experiments. I have not, however, succeeded in
producing the effects produced by Davaine, but I ob-
served — what others who have made similar experi-
ments on rabbits have already noticed — that in these
animals the formation of an abscess constantly increas-
ing in extent, may occur in the subcutaneous cellular
tissue without any general infection taking place. Such
animals have at first no symptoms of disease ; a flat
lentiform hard infiltration at the seat of injection is all
that can be observed. After several days this hardness
extends in all directions, chiefly downwards, especially
towards the abdomen and anterior extremities. The
animal at the same time emaciates and grows feeble,
and dies in about twelve to fifteen days after the
injection.
" The post mortem examination shows the presence,
in the subcutaneous tissue, of extensive flat abscesses
with cheesy contents ; their walls bulge in various
directions, though the whole remains a single cavity.
There is also an extreme degree of emaciation, but no
alteration in the peritoneum, intestine, kidney, spleen,
liver, heart, or lungs. In the blood the white corpus-
cles are greatly increased in number, but no bacteria
can be found. The cheesy contents consist of a finely
granular material, and scattered about in this are nuclei
SPREADING ABSCESS IN RABBITS. 377
undergoing disintegration ; but no bacteria can be defi-
nitely made out. Here, then, we have appearances
similar to those often found in man, and much used as
an argument against the parasitic nature of such morbid
processes. I refer to abscesses resulting from phleg-
monous inflammation, which must be regarded as infec-
tive in their origin, but in which no micro-organisms
have been found.
'• When, however, portions of these abscesses are
hardened, and examined in sections, the surprising
result is obtained that, though bacteria are not present
in their contents, their walls are everywhere formed by
a thin layer of micrococci, united together into thick
zoogloea masses. These organisms are the smallest patho-
genic rnicrococci which I have as yet observed. In
some places I was fortunate enough to find them ar-
ranged in rows, and thus I was able to measure them ;
and I ascertained that they were about .15 //, in diame-
ter. (This is, of course, only an approximate measure-
ment.) . . .
" In order to ascertain whether the morbid process
here designated as progressive abscess formation could
be transmitted from one animal to another, rabbits were
injected with blood taken from others which had already
died of this disease. These injections produced no ef-
fect. A small quantity of the cheesy contents of the
abscess was now taken, diluted with distilled water, and
injected under the skin of a rabbit. . These resulted ex-
actly the same, — abscess formation in this animal as in
the first. The abscesses spread in the same manner
as described in the former case, and caused the death of
the animal experimented on in a week and a half. From
this animal the disease was conveyed to a third, and so
on through several in succession.
" It was thus demonstrated that the disease is not
378 BACTERIA IN INFECTIOUS DISEASES.
merely occasioned by the injection of a considerable
quantity of putrefying blood, but is of a decidedly in-
fective character. The assumption made above, that
the micrococci in the cheesy contents of these abscesses
are dead, does not appear in keeping with this result of
inoculation. This apparent contradiction may, however,
I think, be cleared up ; for it is very probable that these
micrococci, like other bacteria, form resting spores
(Dauersporen) after the expiration of their vegetative
life, and that these bodies, just like the spores of ba-
cillus, are not stained by aniline, and therefore remain
invisible in Canada balsam. The infection in the case
referred to would be brought about by such spores." l
SWINE PLAGUE ; le rouget ou mal rouge des pores
(Pasteur); infectious pneumo-enteritis of the pig
(Klein). In a recent communication (December
4, 1882) to the French Academy,. Pasteur gives
the following summary of results obtained in an
experimental research relating to the above-men-
tioned disease : —
" 1. Swine plague (mal rouge des pores) is produced
by a special microbe, which is easily cultivated outside
of the body of the animal. It is so minute that it may
easily escape observation, even the most attentive. It
most nearly resembles the microbe of fowl-cholera, its
form being that of the figure 8. But it is smaller and
l»->s easily seen, and differs essentially from the microbe
of fowl-cholera in its physiological properties. It has
no action upon fowls, but kills rabbits and sheep.
"II. When inoculated in a pure condition into pigs,
in quantities almost inappreciable, it promptly gives rise
1 Traumatic Infective Diseases, pp. 45-47.
SWINE PLAGUE. 379
to the disease and to death, the symptoms being the
same as in spontaneous cases. It is especially fatal to
the white race (improved breed, most highly valued by
those who raise pigs).
" III. In 1878 Dr. Klein, of London, published an
elaborate research upon this disease, which he calls
infectious pneumo-enteritis of the pig ; but this author
has been entirely mistaken as to the nature and proper-
ties of the parasite. He has described a bacillus with
spores as the microbe of this disease, which he describes
as being even larger than Bacillus anthracis (la bacteride
du charbon). This is very different from the true mi-
crobe of swine plague, and has no relation to the etiol-
ogy of the disease.
" IV. After assuring ourselves, by direct proof, that
the disease does not recur, we have succeeded in in-
oculating it in a mild form, and the animal has subse-
quently proved to be protected against the malignant
form of the disease."
Neguin and Salmon had previously reported
their failure to find the bacillus of Klein in the
blood and other infectious fluids obtained from ani-
mals sick with this disease, and the constant pres-
ence of a minute microeoccus apparently identical
with that described by Pasteur.
Salmon says that blood drawn from the veins of
a pig affected with swine-plague into "capillary
vacuum tubes " was quite free from bacilli at the
end of ten days. But this blood swarmed with
micrococci, single, in pairs (Pasteur's Fig. 8), in
chains, and in zoogloea masses. Healthy pigs in-
oculated with this blood sickened at the end of
seven days and exhibited the characteristic symp-
380 BACTERIA IN INFECTIOUS DISEASES.
torns of the disease. These inoculations did not,
however, produce a fatal form of the malady, and
Salmon found it impossible to carry the virus
beyond a second generation, even by inoculating
pigs which had never before been exposed to the
contagium.
Dr. Klein has recently reasserted his belief that
this disease is due to the bacillus described by him
in his original report, and has given additional
experimental evidence in favor of this view (Jour-
nal of Physiology, Vol. V., No. 1).
SYPHILIS. — The presence of bacteria in the
initial lesion of syphilis, in secondary papules, in
syphilitic new growths, and in the secretions of
chancroids and syphilitic ulcers, has been noted by
numerous observers. But the descriptions given
by different individuals are not entirely in accord
as to the morphological characters of these bacteria.
According to some, — Hallier, Klebs, Bermann, —
they are micrococci ; while others have found
bacilli, — Birch-Hirschfeld, Morison ; and Salis-
bury finds a fungus — his Crypto, syphilitica — in
the blood as well as in the local lesions of syphilis.
Birch-Hirschfeld at first described the organisms
found by him in syphilitic growths as bacilli, but
has since become convinced that they are oval
micrococci arranged in chains. He says that it is
more difficult to distinguish the individual elements
in the chains than in the case of spherical micro-
SYPHILIS. 381
cocci. These oval elements are found single, in
pairs, or in chains of four or five, which greatly
resemble long rods with rounded ends. This
description agrees with that of Aufrecht:
" For the demonstration of the organisms in recent
preparations, Birch-Hirsclifeld prefers potash, by the
clearing action of which the niicrococci are visible in
the tissue, on account of their strong refracting power.
In a broad condyloma, they lie, for the most part, in
small aggregations in the papillae, and in many of the
cells of the adjacent layer of the rete Malpighii. They
may be readily detected in the juice of a recently ex-
cised condyloma, by tinting in the ordinary way ; and
of the various staining agents, Birch-Hirschfeld con-
cludes that fuchsin and gentian-violet are the best. In
the growths in internal organs the smallest micrococci
are most abundant, and the larger forms seen in the con-
dylomata are seldom met with. In gummatous scars
they are sought for in vain. In more recent gummatous
products they were most abundant in parts which had
the aspect of growing granulation tissue. They were
partly scattered, partly aggregated into groups, which
never exceeded a granulation-cell in size ; they were
also distinctly seen within the cells. Many epithelioid
cells seemed to have their nuclei filled with these or-
ganisms." 1
Dr. Bermann of Baltimore finds in absolutely
fresh specimens of indurated chancres, " collections
of micrococci and fungoid growths, firmly adhering
to and partly blocking the lumina of most of the
lymphatic vessels." According to this observer, the
1 London Lancet, December 2, 1882.
382 BACTERIA IN INFECTIOUS DISEASES.
micrococci of syphilis are small, strongly refract-
ing bodies, resembling those described by Klebs.
Recently Dr. Morison of Baltimore has made a
careful study of the bacteria found in chancroids
and in syphilitic lesions, in the wards of Professor
Neumann of Vienna. As he resorted to the most
approved methods of staining, and seems to have
Fig. 20.
Hard chancre secretion with bacteria, magnified 850 diameters. (Drawn by Heitzmann. )
exercised special care in collecting and mounting
his material for microscopic examination, his obser-
vations are of value, and I have taken the liberty
of copying his figures from the " Maryland Medical
Journal" of January 1, 1883, in which his paper
was published. (See Figs. 20 and 21.)
No satisfactory proof has yet been offered in
support of the view that any one of the organisms
above described is the veritable germ of syphilis ;
SYPHILIS. 383
and it is evident that the greatest caution must be
exercised in drawing any conclusions as to their
etiological import. For there is nothing improbable
in the supposition that tissues of a low grade of
vitality may be invaded by parasites which have
no causal relation to the morbid process; and in
view of what we know of the extended distribu-
Fig. 21.
Soft chancre secretion with bacteria, magnified 850 diameters. (Drawn by Heitzmann.)
tion and infinite variety of organisms of this class,
their absence from the secretions of an open ulcer
would be more remarkable than their presence.
In a second communication, dated March 23, Dr.
Morison states that a modification of his method
of staining has enabled him to demonstrate that
the rods seen in Fig. 20 are really formed of
closely united cocci, corresponding with those de-
scribed by Birch-Hirschfeld. He further says : —
384 BACTERIA IN INFECTIOUS DISEASES.
" The result of these recent experiments is such that I am not
only forced to deny the pathogenic nature of the micro-organisms
described in rny first communication, but also to add that I am
convinced their presence in the secretions was due to external
influences."
Klebs claims to have produced syphilis in the
monkey, and Martineau and Hamoine to have
communicated the disease to young pigs (Morison).
But with these exceptions, so far as the writer is
aware, attempts to inoculate syphilis in the lower
animals have given negative results.
TUBERCULOSIS. — The experimental researches
of Villeman, Tappeiner, Colmheim, Toussaint, and
others, having apparently established the fact that
tuberculosis is an infectious disease, the medical
profession was not unprepared for the discovery,
first announced by Koch in the spring of 1882, of
a parasitic micro-organism in tuberculous material,
bearing a causal relation to the disease in question.
Coming from Koch this announcement had great
weight and at once received the most attentive
consideration in all parts of the civilized world ; for
he was already well known to be both a skilful
and a cautious investigator.
The experimental proof offered in favor of the
view that the bacillus discovered in the sputum of
tuberculous patients, and in recent tubercles in the
lungs and elsewhere, was the veritable cause of
tuberculosis, seemed so convincing, that it might
have been received almost without question, but
for the fact that other experimenters had pre-
TUBERCULOSIS. 385
viously found that tuberculosis in animals may
result from inoculation with a variety of organic
products of non- tubercular origin, and even from
the inhalation of inorganic particles ; which also is
recognized as a cause of pulmonary consumption
in man. As an example of the numerous experi-
ments of this kind, we may refer to the results
obtained by Brunet, who inoculated seven rabbits
with cancer, six with, simple pus, and six with
tuberculous material. Of those, fourteen became
tuberculous, namely, six of those inoculated with
cancer, three of those inoculated with pus, and
five of those inoculated with tuberculous matter.
Schottelius found that miliarj7' nodules in the
lungs resulted, in dogs, alike from inhalation of
pulverized — spray — sputum of bronchitis and of
phthisis.
Toussaint affirms that the tubercular deposits
resulting from inoculation with non-tubercular
material are not infectious, and that experimental
pseudo-tuberculosis may be distinguished from
tuberculosis proper by inoculation experiments,
although the pathological anatomy of the two
diseases is identical.
Koch, on the other hand, does not admit that
tuberculosis can be produced by material from
which living tubercle bacilli or their spores are un-
questionably excluded. In his own experiments
he found that in all cases where the material used
for inoculation contained living bacilli or spores,
the result was positive in animals liable to infec-
25
386 BACTERIA IN INFECTIOUS DISEASES.
tion ; while when the material inoculated did not
contain these bacilli or their spores, a negative
result was obtained. Thus, in several cases, ex-
periments were performed with the contents of a
scrofulous gland and with various other material
proved by examination to be free from bacilli, and
in no instance did tuberculosis follow. The posi-
tive results obtained by other experimenters with
non-tuberculous material are explained by the sup-
position that tubercle bacilli or their spores have
been introduced at the same time. It is evident
that this accidental inoculation would be very apt
to occur in laboratories where tuberculous animals
had been kept under observation, and especially
where proper precautions are not taken as regards
cleanliness of the cages in which animals are kept,
and the isolation of those which are subjected to
inoculation experiments.
According to Koch, the tubercle bacillus is a
slender rod from a quarter to a half of the diameter
of a blood-corpuscle in length, and presents certain
distinctive characters as regards its behavior with
staining reagents. The various methods of stain-
ing this bacillus are given in PART THIRD of the
present volume. The bacilli are found in consider-
able numbers in tubercles of recent formation,
more especially at the border of the cheesy masses.
They are abundant in the giant-cells, and seem to
possess a special relation to these cells. They are
not so abundant in old tubercles, although they are
seldom entirely absent. By placing a small por-
TUBERCULOSIS. 387
tion of a recent tubercle in blood-serum or distilled
water, they may be recognized with a suitable
objective and illuminating apparatus, without the
use of staining reagents. An examination made
under these circumstances shows that the bacilli
are motionless, and in some rods spores of oval
form may be distinguished. At the time of his
first report, Koch had examined in man, " Eleven
cases of miliary tuberculosis, twelve cases of cheesy
broncho-pueumonia, one case of tubercle in the
brain, and two cases of intestinal tuberculosis." In
all of these the bacilli were present. They were
also found in freshly extirpated scrofulous glands.
Among the lower animals they were found in ten
cases of perkucht, in three cases of so-called bron-
chiectasis in cattle ; in three monkeys, nine guinea-
pigs, and seven rabbits, which had spontaneous
tuberculosis ; and in one hundred and seventy-two
guinea-pigs,. thirty-two rabbits, and five cats, which
had been inoculated with tuberculous material, or
with pure cultures of the bacillus.
The gelatine culture-medium which had been
previously recommended by Koch was found not
to be suitable for the cultivation of the tubercle
bacillus, as the advantage of solidity is lost when
this is heated to 98° Fahr. Jellified blood-serum,
prepared as directed on page 163, was found, how-
ever, to fulfil all the required conditions, and was
used by Koch in his culture experiments. Portions
of tubercles removed, with proper precautions to
prevent contamination, from the bodies of persons
388 BACTERIA IN INFECTIOUS DISEASES.
recently dead of tuberculosis, or from the lower
animals, victims of spontaneous or of induced tu-
berculosis, were placed upon the surface of the
sterilized blood-serum, and the vessel containing it
was kept in a culture-oven maintained at a tem-
perature of 40° C. (104° Fahr.). During the first
week no marked alteration occurred, unless other
bacteria had gained access to the culture-medium,
in which case the experiment was a failure. About
the tenth day small points and scales became evi-
dent, which slowly spread, and upon microscopical
examination proved to consist of tubercle-bacilli.
After fourteen days these bacilli were used to start
a new culture. This was accomplished by break-
ing up the scales and transferring a minute quan-
tity to the surface of culture No. 2. After
transferring the bacilli in this way to several
successive flasks, it was assumed that the origi-
nal material was excluded, and that a pure cul-
ture had- been obtained. Inoculation of guinea-pigs
with these pure cultures gave rise to tuberculosis
with as great certainty as in those experiments in
which tubercular material was used. In one ex-
periment six newly bought guinea-pigs were ob-
tained. Two of these were kept as temoins, and
the other four were inoculated with cultivated
bacilli obtained in the first instance from the lung
of a human being who had died of military tuber-
culosis. In this instance five successive cultures
had been carried out, the time required being fifty-
four days. One of the inoculated guinea-pigs died
TUBERCULOSIS. 389
on the thirty-second day, and all the rest were
killed on the thirty-fifth day. All had extensive
tuberculosis, and the Bacillus tuberculosis was found
in the tubercles of the lungs, and of various
organs. The two guinea-pigs not inoculated re-
mained healthy.
In another experiment four rabbits were taken.
Into the eye of one pure blood-serum was injected ;
the point of a syringe containing tubercle bacilli in
blood-serum was introduced into the eye of a sec-
ond. These were from a series of cultures carried
out for 132 days. In this case the piston was not
moved ; but the same material was injected into
the eye of rabbit No. 3, and of rabbit No. 4.
The animals were killed on the thirtieth day, and
the following result noted : Rabbit No. 1 remained
healthy ; rabbit No. 2 had typical tuberculosis of
the iris, and the nearest lymphatic glands were
swollen and infiltrated with yellowish nodules ;
but the lungs and other organs were free from
tubercles. Rabbits Nos. 3 and 4 had iritis and
tuberculosis of the lungs.
The presence of Koch's bacilli in tuberculous
sputum has now been confirmed by numerous ob-
servers in various parts of the world ; and the
comparatively few failures to find the bacillus
which have been reported by expert manipulators
since the method of Ehrlich was published, are
easily accounted for in other ways than upon the
supposition that cases of tuberculosis occur in
which no bacilli are found. Nevertheless we must
390 BACTERIA IN INFECTIOUS DISEASES.
admit that there are cases, recognized by expert
pathologists as undoubtedly tubercular, in which
no bacilli can be found in tubercles obtained from
the lungs post mortem. Thus Prudden, of New
York, while recording the fact that he has, in a
considerable number of cases of acute and chronic
phthisis, found, almost invariably, the bacillus of
Koch " in and about all of the cavities, in many
of the larger areas of coagulative necrosis, and in
a considerable proportion of the miliary tuber-
cles;" yet reports two cases which form an ex-
ception to this rule. In one, an abundance of
miliary tubercles covered the lateral surfaces of
both lobes of the left lung; "most of these were
of the usual giant-celled and epithelioid-celled
type, with a more or less well-marked reticulum.
In none of those examined was there well-marked
cheesy degeneration. Six hundred and ninety-five
sections, about .01 millimeter in thickness, were
made from ninety-nine different tubercles from
various parts of the tuberculous membrane, and
stained in the usual manner by Ehrlich's method
in several different lots. In not one of these six
hundred and ninety-five sections could a single
tubercle bacillus be detected, although all were
examined with the most scrupulous care." In
another case, " nine hundred and nine sections
from a large number of peritoneal tubercles, from
different parts of the affected surfaces, stained by
Klirlich's method, revealed, under the most search-
ing scrutiny, no tubercle bacilli." In the same
TUBERCULOSIS. 391
case, however, nodules at the apex of the lung,
and the wall of a small cavity formed of shreds
of necrotic tissue, of dense cheesy material, and in
the outermost layers of tubercle tissue and ordi-
nary dense connective tissue, proved to contain
the bacillus in abundance in the ivatts and edges of
the cavity, and in a few of the dense areas of coagu-
lation necrosis in its immediate vicinity. But in
the diffuse tubercle tissue, in the zones of simple
pneumonia around the nodules, in the scattered
fibrous tubercles in the lung and pleura, and in
the well-formed tubercles in the bronchial glands,
no bacilli could be found.
Koch has received ample confirmation as to the
presence of the bacillus described by him, in
phthisical sputum ; and its absence from the spu-
tum of patients suffering from other diseases seems
to be pretty well established, although Spina of
Vienna claims that other bacteria behave pre-
cisely towards staining agents as do the bacilli of
Koch ; and, consequently, that the color-test can-
not be relied upon for distinguishing this bacillus
from the ordinary bacteria of putrefaction. The
writer's observations are entirely in favor of the
statement of the discoverer of the tubercle bacilli
as to their peculiar color reaction when treated by
Ehrlich's method; but, like many others, he has
not been successful in demonstrating them by the
method first proposed by Koch.
A recent writer1 has collected the statistics, as
1 Dr. Ferguson, of Canada. See Med. Record, New York, July 21,
1883, p. 77.
392 BACTERIA IN INFECTIOUS DISEASES.
\
published in various journals, and states that in
2,509 cases reported, the bacilli were found in
2,417- Koch, himself, recognizes, however, that
this kind of evidence cannot be taken as proof of
the causal relation of the bacillus to the morbid
process which results in the formation of tubercles
in various parts of the body. For it may be that
the bacillus is present in tuberculous material
simply because this furnishes the pabulum neces-
sary for its development, and is absent from the
sputum of bronchitis, for example, because this
does not constitute a suitable culture-medium ; or
because, being secreted from the surface of an
inflamed mucous membrane, and quickly removed
by expectoration, there is no time for the develop,
ment of this bacillus, which Koch has shown re-
quires at least a week before any evidence of
multiplication is seen upon the surface of sterilized
blood-serum. This time would, however, be af-
forded in the cheesy contents of a tubercular
nodule, or in a cavity where necrotic products
were retained for a considerable time.
A recent French writer, Cochez, claims that the
sputum of phthisical patients constitutes a favora-
ble culture-medium for the tubercle bacillus. The
writer, also, has been inclined to believe that the
bacilli are more numerous in sputum which has
been kept for a day or two than in the same
material when first obtained. This, if true, is not
very favorable to the view that they are the cause
of the morbid process which results in the forma-
TUBERCULOSIS.
393
tion of miliary tubercles, although by no means
directly opposed to this belief.
An interesting communication relating to the
finding of Koch's bacillus in pathological speci-
mens which have undergone putrefaction, or in
those which have been kept for some time in pre-
servative solutions, has recently been made by Vig-
nal. This author finds that " putrefaction, even
very much advanced, does not seem to interfere
with finding the tubercle bacillus. They are also
found as easily in pieces kept a long time in 90
per cent and absolute alcohol, and in Muller's fluid,
as in recent preparations."
The morphological characters of the tubercle
bacillus, as found in sputum, are delineated in
Fig. 22. The bacilli are
found both within and
without the pus-cells,
and seem to be espe-
cially numerous in the
epithelioid cells. They
vary greatly in length,
and are not infrequently
curved or bent at an
angle more or less acute.
Not infrequently they
occur
little
in pairs, or in
groups,
and
in
Fig 22.
Koch's Bacillus tuberculosis, in sputum;
stained by Ehrlich's method. X 1000
(G. M. 8., del.)
some cases it is apparent that they contain endo-
genous spores, or that they are made up of a chain
of oval elements.
PLATE IX.
Bacillus Tuberculosis.
FIG. 1. — Section of miliary tubercle of lung; the tubercle
bacilli stained blue, and the cell nuclei brown. X 700. Koch
(from Mitth. a. d. k. Gsndhtsamte Vol. ii. Taf. I. Fig. 2).
FIG. 2. — Colonies of tubercle bacilli from surface culture.
X 700. Koch (op. cit. Taf. IX., Fig. 44).
FIG. 3. — Giant-cell containing tubercle bacilli, from a caseous
bronchial gland of a case of miliary tuberculosis. X 700. Koch
(op. cit. Taf. XI. Fig. 9).
PLA -
» "* • tffw « •
V
,-K
^
^*
«Jf
%y
**
Fis 3.
_
TUBERCULOSIS. 397
In the first edition of this work the writer gave
a summary of results obtained in his own experi-
ments, made soon after the announcement of Koch's
discovery. This has been omitted from the pres-
ent edition to make room for Plate IX, which is
an accurate reproduction of the selected figures,
copied from Vol. II. of the " Mittheilungen."
In the experiments referred to, several rabbits
and two guinea-pigs were successfully inoculated
with tuberculous sputum, and an attempt was
made to cultivate the bacillus, but without success.
Failure was probably due to the fact that, not
having a supply of gas at the military post where
the experiments were conducted, it was found
impossible to regulate the temperature of the
culture-oven to as nice a point as appears to be
necessary. " In the animals successfully inocu-
lated the enlarged tuberculous lymphatic glands
in the vicinity of the point of inoculation, and
tubercle nodules in the lungs and elsewhere, usually
contained the bacillus of Koch. But this was not
invariably the case." The writer is at present
inclined to believe that a more protracted search
might have demonstrated their presence in every
case. Some recent experiments made in Balti-
more (not yet published), and a careful considera-
tion of the experimental evidence as given by
Koch in his elaborate memoir in the second volume
of the " Report of the Imperial Board of Health,"
have removed the last remnant of scepticism from
the writer's mind ; and to-day he considers it
established that tuberculosis is an infectious dis-
398 BACTERIA IN INFECTIOUS DISEASES.
ease, in which the essential etiological agent is the
bacillus discovered by Koch. The possibility that
the special pathogenic power of this bacillus is an
acquired rather than an essential physiological
character, depending upon the fact that it has
been bred for many successive generations in a
tuberculous soil, and that it is in truth a pathogenic
variety of a common and widely distributed species,
seems to be worthy of further consideration.
Dr. Watson Cheyne of London, a very compe-
tent, witness in a case of this kind, has repeated
Koch's experiments, and fully confirms him in all
essential particulars.
This author paid a visit to Toussaint and to
Koch for the purpose of making himself familiar
with their methods. Upon his return to England,
a series of experiments was made, with the results
reported below.
The experiments were made under the most
favorable hygienic conditions, and all possible pre-
cautions were taken as regards disinfection of
instruments and the complete isolation of the ani-
mals used. Twenty-five animals, inoculated with
non-tubercular material in various ways, failed to
become tuberculous. In six of these, setons were
introduced subcutaneously ; in ten, vaccine lymph
was employed ; in three, pyoemic pus was injected ;
and in six, various materials were introduced into
the abdominal cavity (cork, tubercle hardened in
alcohol, worsted thread). Cheyne believes that
in similar experiments 'made by other observers, in
which a positive result has been reported, the
TUBERCULOSIS. 399
tubercle bacilli have always been introduced acci-
dentally, with the innocuous material to which the
result has commonly been ascribed.
Toussaint, who has ascribed the disease to a
micrococcus, furnished our author cultures of this
micrococcus obtained by inoculating blood-serum
or rabbit bouillon with the blood of a tuberculous
animal. This material was injected into three
rabbits, two guinea-pigs, one cat, and one mouse.
In no instance did tuberculosis ensue. The injec-
tions in Cheyne's experiments were made, when-
ever practicable, into the anterior chamber of the
eye, with a syringe which had been purified by
heat. Cultivations of the micrococci obtained from
Toussaint were also made and injected into nine
rabbits and three guinea-pigs, with a negative
result. The tuberculous organs of animals ex-
perimented upon by Toussaint were examined by
Cheyne, who found in them, often in large num-
bers, the bacillus of Koch, but no micrococci ;
although some of these animals had developed
tuberculosis as a result of inoculation by Toussaint,
with cultures of the micrococcus described by him.
This result is ascribed to accidental inoculation
with the spores of the tubercle bacillus, which
Cheyne shows would not be destroyed by the
method of disinfection upon which Toussaint has
relied, namely, the cleansing of his syringe with
an aqueous solution of carbolic acid.
Twelve rabbits were also inoculated with culti-
vations of the tubercle bacillus obtained from Koch.
400 BACTERIA IN INFECTIOUS DISEASES.
"All of these became tuberculous, and that more rapidly
than after inoculation with tuberculous material. The
tubercles produced in these cases were infec-
tive and produced tuberculosis in other animals.
On examination of tuberculous material, Koch's
bacilli are always found, though in varying num-
bers. They are most numerous in bovine tuber-
culosis, and least numerous in human tuberculosis.
About eighty organs of tuberculous animals and
thirty-six cases of human tuberculosis were ex-
amined, and in all of these, without exception,
tubercle bacilli were found." 1
TYPHOID FEVER. — The established facts relating
to the origin of isolated cases and local epidemics
of typhoid fever all point to the existence of a
contagium vivum capable of self-multiplication ex-
ternal to the human body, and which commonly
gains access to the intestinal canal of those at-
tacked with the disease through the ingestion of
infected material, and especially of unboiled fluids,
particularly of water and milk. It is generally
recognized that the infective agent is contained in
the stools of typhoid patients, and that it may in-
crease indefinitely in a proper pabulum, and under
favorable conditions as to temperature, when these
stools are carelessly mixed with organic material
in cess-pools, privy-vaults, etc.
There is nothing in the clinical history of the
1 Quoted from abstract in " Braithwaite's Retrospect," Part LXXX VII.
p. 73.
TYPHOID FEVER. 401
disease under consideration, or in known facts
relating to its epidemic extension, to indicate that
the typhoid germ multiplies in the blood of those
attacked with the disease ; and the negative results
which have, for the most part, been reported by
those who have sought it in this fluid, correspond
with what might a priori have been expected.
Meyer, however, has reported the finding of
bacilli in great numbers in the blood of a case of
typhoid which resulted fatally from congestion
of the lungs and kidneys, at the end of two days.
But it may be questioned whether the pathological
appearances would be sufficiently marked at so
early a date to establish the diagnosis ; and, in
any event, the finding of micro-organisms in blood
obtained post mortem has little import, unless the
same organisms were found in this fluid before
death. Almquist reports that he has occasionally
found groups of microbes in the blood in small
numbers. These were short rods, and were most
abundant during the second or third week of sick-
ness. In this, as in other diseases, we must bear
in mind the possibility that a septic complication
may be attended by invasion of the blood by micro-
organisms not bearing any direct relation to the
typhoid process; and also that non-pathogenic
bacteria may possibly invade the circulating fluid
when the vital powers are at a low ebb.
Maragliano found in blood drawn from the spleen
by means of a hypodermic syringe, motile and
motionless micrococci, and also a small number of
26
402 BACTERIA IN INFECTIOUS DISEASES.
rods like those described by Eberth. Letzerich
also claims to have recognized the rnicrococci
which he supposes to be the specific germs of
typhoid in the blood and in the sputum. Moxon,
iu a recent paper " On our Present Knowledge of
Fever/' remarks as follows : —
" You must not suppose that one has only to get a
microscope and a slide and put a little fever blood under
it to find it full of germs. No ; try in any of our cases
of typhoid in the wards, and you will find these germs
by no means very easily discovered or obvious things.
At the outset of such an inquiry, you must take notice
that the blood-serum is often crowded with minute par-
ticles, which must not be confounded with bacteria, and
which exist, often to a large extent, in the blood of
healthy persons. During last winter's clinical session,
some of my most acute and intelligent -friends searched
carefully for germs in the blood of several severe typhoid
cases. The result was that one bacterium was seen,
only one, but I was told it was a very active one. When
I say that Mr. Booth saw it, you will know it was well
seen, for we all regard Mr. Booth as one of the very
ablest and very best students at Guy's; but perhaps
the main fact was that all were quite sure that there
was only one bacterium." l
The attempts which have been made to produce
typhoid fever in the lower animals have not given
any results of a sufficiently definite character to
make it possible to study the etiology of this dis-
ease by the method of inoculation with pure-cul-
tures of suspected organisms. And for the present
1 Lancet, December 9, 1882, p. 974.
TYPHOID FEVER. 403
the evidence in favor of the various organisms
which have been supposed by different observers
to be the veritable typhoid germs, is mainly that
obtained by the microscopical examination of the
tissues involved in the local lesions which character-
ize the disease. When we consider that the healthy
intestine is the usual habitat of a large number of
species of bacterial organisms, and that some of
these promptly invade necrotic tissues, — and pos-
sibly living tissues having a low grade of vitality,
or which are deprived of their normal relations by
inflammatory exudates which furnish a suitable
pabulum for parasitic micro-organisms, — we shall
appreciate the difficulty of deciding whether necro-
sis of invaded tissues is a result of the parasitic
invasion, or whether the mycosis has been secondary
to and independent of the morbid process.
Eberth seems to have very fully appreciated
these difficulties, and it is doubtful whether any
more satisfactory evidence can be obtained than
that which he has offered in favor of the view that
the bacillus described by him is the much sought
typhoid germ, unless future experiments upon
the lower animals give more definite results than
have been heretofore reported. As pointed out by
Eberth, the results reported by Walder in his experi-
ments upon calves, dogs, cats, rabbits, and chickens,
are entirely unreliable, as no account seems to
have been made of septicsemic complications which
could scarcely fail to occur from the ingestion of
putrid material, — blood, typhoid stools, etc., used
404 BACTERIA IN INFECTIOUS DISEASES.
in many of his experiments. Letzerich also seems
to have been ignorant of the fact that the sputum
of healthy persons produces septicaemia in rabbits,
and his inference that rabbits inoculated with the
sputum of a fever patient suffered an attack of
genuine typhoid, is probably as wide of the mark as
was Pasteur's with reference to the u new disease "
described by him as resulting from inoculating
rabbits with the saliva of a child dead of hydro-
phobia. One of Letzerich's rabbits died at the
end of five days, and one was killed at the end of
twelve days. Micrococci and rods were found in
the spleen, in the veins, and in the follicles of the
intestine, but the evidence presented in favor, of
the view that these animals had typhoid fever is
entirely unsatisfactory.
Brantlecht produced in young rabbits most of
the typhoid symptoms by the subcutaneous injec-
tion of culture-liquids; but he obtained the same
results with bacilli found during the summer months
in the water of stagnant ponds (Cameron). Chom-
jakoff, a pupil of Klebs, injected typhoid ba-
cilli (?) into the peritoneum of rabbits. The
animals immediately exhibited an elevation of
temperature, which attained its maximum on the
third day. They all died on the third or fourth
day, in two instances with diarrhoea. The lesions
were, redness and tumefaction of Peyer's glands,
increase in volume of the spleen, cellular infiltra-
tion of the intestinal tissues. The presence of
micrococci was doubtful, but the peritonitis was in
TYPHOID FEVER 405
inverse ratio to the cultivation. The evident criti-
cism in experiments of this kind is that the results
are necessarily complicated by the peritonitis re-
sulting from the introduction of micro-organisms
into the cavity of the abdomen ; that the symp-
toms follow the injection immediately, while in
man there is a certain period of incubation ; and
that the death at the end of four days of an animal
very susceptible to various forms of septicsemia,
but which, so far as we know, never contracts
typhoid fever spontaneously, can hardly be taken
as evidence that the micro-organisms injected into
its peritoneal cavity were veritable typhoid germs.
Indeed, we cannot help suspecting that other in-
vestigators operating with micro-organisms from
other sources would have found in the symptoms
and pathological lesions evidence of yellow fever,
or of continued malarial fever, or possibly of scarlet
fever, without the rash ; for the absence of the
characteristic rash could be easily explained by
the fact that the integument is thickly covered
from sight by a heavy growth of hair. Klebs
also introduced cultivated typhoid organisms into
the cavity of the abdomen in eleven rabbits. In
one only death occurred at the end of four days ;
and upon this slim foundation the inference was
made that the organisms used in the experiment
were veritable typhoid germs.
44 Tigri first found bacteria in the blood of a man dead
with typhoid fever. These organisms were also found
by Signoi (1863) and Megrim (1866) in the blood of
406
BACTERIA IN INFECTIOUS DISEASES.
horses attacked by a disease called by the veterinarians
typhoid fever. This blood, by inoculation, produced the
death of some rabbits, with the same alterations in the
blood.
" Coze and Feltz (1866), having inoculated some rab-
bits with the blood of typhoid fever, have produced
results which they consider analogous, and as accom-
panied by the same pathological localizations in the
glands of Peyer. The blood of an injected rabbit may
be used upon a second rabbit, with positive results, as
in variola and scarlatina.
" The species of Bacterium which is found in this case
recalls the Bacterium catenula, but its dimensions are
less." (Magnin.)
The presence of micro-organisms in the local
lesions of typhoid fever has been verified by
numerous observ-
ers, and, as already
remarked, was a
priori to have been
expected. The sta-
tistics of these ob-
servations, there-
fore, which Eberth
has
given us,
al-
though interesting,
have comparatively
little value. Ac-
cording to this au-
thor, Von Reck-
lingliausrn first
described micro-organisms in abdominal typhus.
Fig. 23.
Vertical section of intestine, typhoid feyer, showing
the border of the submucoea infiltrated by ha-
cilll. Hartnack im. No. 9, Ocular 2 (Klebs).
TYPHOID FEVER.
407
Fig. 24.
These were found in the typhoid ulcers, and con-
sisted of masses of micrococci. Klein also found
groups of micro-
cocci in the mucous
membrane, in the
lymph follicles, and
in the spleen. Fische
found colonies of
micrococci in the
spleen and in the
lymphatic glands in
fifteen outof twenty-
nine cases exam-
ined. The positive
results were mostly
From a fresh section of typhoid intestine ; treated
Obtained in recent withglacial acetic acid and glycerine mixture.
n , i Sieberfs im. No. 7, Ocular 3 Klebs).
cases; some of these,
however, gave a negative result. Klebs found
organisms — micrococci or bacilli — in twenty-four
cases examined by him. Koch found bacteria in
half the cases which he examined ; Meyer in
eighteen out of twenty-four; and Eberth in
eighteen out of forty. Eberth remarks that the
result would probably have been more favorable
but for the fact that the organism in many cases
seems to have been destroyed in the tissues. In
the negative cases the height of the fever was
already past. The bacilli are said to be most nu-
merous during the first twelve or fourteen days of
sickness, less numerous at the end of the third
week, and they were seldom met with in the fifth
408 BACTERIA IN INFECTIOUS DISEASES.
or sixth week; if found then they present evi-
dence of having undergone retrograde change.
The typhoid germ of Letzerich is a rnicrococcus,
isolated, in colonies, or in chains, very dissimilar
to those of diphtheria and of infectious pneumonia,
but which by cultivation may reach twice or three
times the size of the micrococci of the last men-
tioned diseases.
Klebs describes his Bacillus typhosus as large-
sized filaments of 50 p in length and 0.2 ^ in
breadth, without
segments or rami-
fications. When
the spores make
their appearance
the filaments may
reach 0.5 p. in
breadth. The
spores are ar-
ranged in a line,
and very close
together. Before
Fig. 26. « ,
they are formed,
Section of typhoid lung ; fresh; treated with mixture .
of glycerine and glacial acetic acid. Siebert's tll6 baCllll CXlSt
as short rods (see
Figs. 23, 24, and 25).
The morphological characters of the bacillus of
Eberth are shown in Fig. 26, which is copied from
his paper, referred to in bibliography.
When these bacilli are present in great numbers
they have the appearance of masses of micrococci.
TYPHOID FEVER.
409
Fig. 26.
Typhoid bacilli from a lymphatic
gland. Hartnack No. 12, Ocu-
lar 3. (From Eberth, "Der
Typhus-bacillus und die intes-
tinale Infection.")
But when isolated from these
masses they are recognized
as short thick rods having
rounded ends. With high
powers many of the bacilli
may be seen to contain two
or three granules, which are
probably spores. The rods
are sometimes found, in the
juice scraped from the freshly
cut surface of a diseased
lymphatic gland, in chains
of two or three elements. The characters by which
these bacilli are recognized are the rounded ex-
tremities, and the fact that they are not so deeply
stained by the aniline dyes as are the putrefaction
bacteria often found in the same preparation. In
addition to these bacilli, Eberth recognizes at least
seven micro-organisms which he has met with in
his microscopical studies, and which may be asso-
ciated with them. But the bacillus with rounded
ends is said to be peculiar to typhoid, and has not
be'en found in a single instance out of twenty-four
cases of intestinal disease of a different character,
— e. g., tuberculosis of the bowels, — in which he
has made a careful examination by the same meth-
ods. Similar negative results were obtained by
Mayer in six cases of dysentery and other diseases
of the bowels. Koch is of the opinion that the
bacillus of Eberth is the only one which has a
specific relation to the disease. According to this
410 BACTERIA IN INFECTIOUS DISEASES.
observer Klebs's elongated bacilli belong to the
putrid parts, and only invade the necrotic tissues
which have succumbed to the attack of the spe-
cific typhoid bacillus.
Eberth also describes a small and comparatively
long bacillus, which no doubt corresponds with that
of Klebs, which is found isolated and in groups in
the superficial layers of the necrotic tissues. "Their
appearance and color-reaction show them to be
ordinary putrefaction bacteria of the intestinal
contents.'* As evidence of the number of bac-
terial organisms constantly present in the intesti-
nal canal of healthy persons, the reader is referred
to the photo-micrograph in Plate VII., Fig. 4. This,
however, by no means shows all the forms which
may be found at different times in the discharges
of persons in perfect health. (See also Plate XIII.,
illustrating the writer's paper on " Bacteria in
Healthy Individuals " in Vol. II, No. 2, of " Stud-
ies from the Biological Laboratory " Johns Hop-
kins University.)
Coates, of Glasgow, confirms Eberth as to the
presence of the bacillus described by him in a dis-
eased lymphatic gland removed from a case of
typhoid fatal on the ninth day. Crook has also
found the bacillus in a case treated in the Fever
Hospital of Leeds.
The writer would simply remark, in regard to
this bacillus, that the distinctive character upon
which Eberth chiefly relies, seems hardly sufficient
to establish it as a distinct species, when we com-
ULCER ATIVE ENDOCARDITIS — VARIOLA. 411
pare his figure (Fig. 26) with that of Cheyne
(Fig. 28), and with my photo-micrograph, Fig. 1,
Plate VIII. Certainly the rounded ends of this
typhoid bacillus are not peculiar to it. (The
photo-micrographs referred to have been omitted
from this edition.)
ULCERATIVE ENDOCARDITIS. — " In this affection, it
is well settled to-day that the cardiac walls and, above
all, the valves, are covered with parasitic masses. Some
think that the malady is due to the introduction of
these parasites into the interior of the tissues ; others,
on the contrary, like Hiller, deny that the bacteria bear
any casual relation with the lesions of ulcerative endo-
carditis." (Magnin.)
VARIOLA. — " The partisans of the parasitic nature of
variola may be divided into two groups : 1. Those who,
with Coze and Feltz, attribute the virulence to a Bac-
terium ; 2. Those who, with Luginbiihl and Weigert,
attribute it to a Micrococcus. Coze and Feltz have in-
deed discovered bacteria in the blood of variola, and
this blood injected into the veins of a rabbit has given
it a mortal malady, which these observers consider vari-
ola. But Chauveau has shown that the affection which
proved fatal to the subjects of the experiment was not
and could not be variola. Another objection is that
bacteria are not found in all those who suffer from
variola. However, Coze and Feltz and Baudouin affirm
that there are in variolous blood numerous rods, of
which the appearance is similar to that of Bacterium
bacillus and Bacterium termo of Miiller. These ele-
ments do not at all resemble those found in other
infections, and when inoculated possess the power of
reproducing variola.
"As to the Micrococcus of variola, they have been
412 BACTERIA IN INFECTIOUS DISEASES.
studied by Luginbiihl, Weigert, Hallier, and Cuhn.
These micro-organisms possess the characters of all the
spherical bacteria, and are found in the variolous pus-
tules, the rete Malpiyldi, the liver, the spleen, the kid-
neys, and the lymphatic ganglia. We can only insist
upon the fact of the concomitance of the variola and
the presence of micrococci, since experiment cannot be
resorted to in this disease, of which the complete evolu-
tion occurs only in man. We also find in vaccine lymph
micrococci analogous, in every point of view, to those of
variola. Cohn considers them both, not as distinct
species, but as two races of the same species, — the
Micrococcus vaccince." (Magnin.)
"M. Straus presented to a recent meeting of the
Socie'te' de Biologic at Paris a series of microscopical
preparations of the vaccinal pustule of the calf, at dif-
ferent stages of its progress, in which the presence of
the special micrococcus could readily be observed. The
method of preparation adopted was to place the excised
fragments of skin in absolute alcohol, to cut sections,
and stain by Weigert's method (methylamine violet),
and then discoloring them until only the nuclei, the
bacteria, and micrococci remain visible. Under a high
power, the latter were visible as extremely minute
points, tinted blue, about a thousandth part of a milli-
meter in diameter, and grouped in colonies. They were
seen in the borders of the inoculation wound, and in
the Malpighian layer, and subsequently could be traced
passing into the subjacent cutis, especially in the lym-
phatic spaces. The multiplication and extension of the
organism seemed to coincide closely with the develop-
ment of the pustule." l
Dr. Wolff claims to have successfully cultivated
1 J. Koy. Microscopical Soc , Oct. 1882, p. 661.
VARIOLA OF PIGEONS. 413
the micrococcus vaccince through fifteen successive
generations.1 If this is true he will be able to
claim the prize offered by the Grocers' Company
of London : —
44 The subject of the Grocers' Company's first discov-
ery prize of X 1,000 for original research in connection
with sanitary science is 4 A method by which the vac-
cine contagion may be cultivated apart from the animal
body, in some medium or media not otherwise zymotic';
the method to be such that the contagium may by means
of it be multiplied to an indefinite extent in successive
generations, and that the product after any number of
such generations shall (so far as can within the time be
tested) prove itself of identical potency with standard
vaccine lymph.' The prize is open to universal compe-
tition, British and foreign. Competitors for the prize
must submit their respective treatises on or before the
31st of December, 1886, and the award will be made
as soon afterwards as the circumstances of the compe-
tition shall permit, but not later than the month of
May, 1887. All communications on the subject must
be addressed to the clerk of the Grocers' Company,
London, from whom circulars giving the conditions can
be obtained."
VARIOLA OF PIGEONS. — In a communication
to the French Academy, presented by Vulpian,
M. Jolyet gives an account of an experimental re-
search, made in collaboration with MM. Delage
and Lagrolet, relating to the etiology of the dis-
ease known as variola of the pigeon or picote. He
says : —
1 Berlin Klin. Wochenschrift, Jan. 22, 1883.
414 BACTERIA IN INFECTIOUS DISEASES.
" Microscopical examination of the blood of pigeons
attacked with variola shows that this liquid contains an
infinite number of living microbes. This alteration
is constant, and is true in the case of pigeons attacked
spontaneously, as well as of those which have been sub-
jected to experimental inoculation.
" Upon studying the development of the microbes in
the blood, the following facts worthy of note may be
observed. The first important point consists in the
progressive development of the organisms in correspond-
ence with the progress of the disease. Their appear-
ance in the blood always precedes the appearance of
morbid phenomena. This fact is especially easy of
verification in pigeons which have been inoculated,
by means of a vaccination needle, either with the blood
of a sick animal, or with the liquid contained in the
pustules.
" If after inoculation we examine each day the blood
of pigeons, we shall find that during the first, second,
and often the third day, it presents nothing abnormal in
its appearance ; however, towards the end of the third
day an attentive examination will already demonstrate
the presence of the microbes in the blood ; the following
days the parasite increases rapidly, and when the pigeon
presents manifest symptoms of illness, a microscopic
preparation of the blood offers myriads of microbes in
movement.
" This period, from the time of inoculation until the
development of morbid phenomena, corresponds with
the period of incubation so characteristic of other viru-
lent and contagious maladies. The greatest number of
parasitic organisms are found in the blood just before
the eruption appears. Subsequently they gradually
decrease in number.
"The pus of the pustules contains the characteristic
WHOOPING COUGH. 415
microbes in abundance, and produces the disease when
inoculated into healthy pigeons. . . .
44 In a certain number of pigeons the cutaneous erup-
tion is wanting, and in this case the autopsy reveals a
veritable intestinal pustulation.
44 The microbes from the pustules or from the blood,
cultivated in pigeon bouillon, have furnished successive
culture-liquids which, when inoculated, reproduce the
disease.
44 But it is the blood (in vitro) and the lymph which
are the best culture media for the microbes of variola,
either of man or of the lower animals. And neverthe-
less, if we examine the blood of subjects attacked with
variola (man, the pig) we find that it contains but few
microbes, so that it is difficult to suppose that these or-
ganisms are the first cause of the malady. So also in
charbon, in many animals but few bacteries are found in
the blood at the moment of death. This is because,
in the living animal, the most favorable medium for
the development of these infectious organisms is the
lymph. Numerous observations enable us to affirm
this fact. . . .
44 In conclusion we will say that if the microbes in the
course of an infectious malady do not multiply in the
blood in circulation, they are susceptible of multiplica-
tion in the blood in repose, drawn directly from an
artery into Pasteur's flasks — sterilized, and that they
retain their specific qualities."
WHOOPING COUGH. — 4t Poulet, in 1867, found certain
bacteria of a peculiar kind in the sputa of patients affected
with pertussis ; Letzerich commenced a series of investi-
gations a few years later. The latter found constantly
present in the sputum of pertussoid patients a bacterium
belonging to the genus Ustiligo, Tul. ; with this he
416 BACTERIA IN INFECTIOUS DISEASES.
inoculated the tracheal mucous membrane of tracheo-
tomized rabbits and noted the results. He invariably
produced a spasmodic catarrhal affection resembling
whooping-cough, and he observed that the bacteria
do not penetrate the epithelium, but live on the sur-
face of the mucous membrane, to the detriment of the
latter.
" Tschamer, of Gratz, working in the same depart-
ment of micro-pathology, has lately found, in the expec-
toration of pertussis, a microphyte, which he identifies
with a black mould which develops on orange-peel.
This he thinks that he has proved by different cultures.
Satisfied of the identity, he took some of the black
powder which constitutes the mould of orange-peel and
experimented with it on himself, inhaling the powder as
deeply as he could. At first no effect was observed,
but after eight days he began to have convulsive fits of
coughing, and expectorated the fungus in abundance.
'* He explains the phenomena of whooping-cough in
this way. After an incubation of seven days, these mi-
crophytes determine an irritation of the bronchi which
induces catarrh and spasmodic cough ; then, as the irri-
tation increases, the expectoration becomes more abun-
dant and eliminates the fungoid organisms.
" Dolan, in repeated experiments, found that by in-
oculating rabbits with the sputum of whooping-cough
patients, he not only induced a catarrhal spasmodic
affection, but the death of the animal generally ensued.
Inoculation with the blood of such patients was without
effect. This certainly seems to confirm the conclusions
of Letzerich, that the materies morbi, — be it a bacillus,
or be it what it may, — lives on the surface of the epi-
thelium, and does not get into the blood." l
1 The Medical Record, February 17, 1883, p. 185.
YELLOW FEVER. 417
The writer has italicized the sentence in which
the editor of the "Medical Record" has inciden-
tally remarked that the death of the animal gen-
erally ensues, and would respectfully call attention
to his experiments relating to a fatal form of septi-
caemia in rabbits resulting from the subcutaneous
injection of the saliva of healthy individuals.
YELLOW FEVER. — In a paper contributed to
the American Journal of the Medical Sciences
(April, 1873), the writer has stated the a priori
argument in favor of the germ theory as regards
the etiology of yellow fever in the following
language :
" There are three agents, to one of which we must (in
the present state of our knowledge) refer the poison,
which, by its action upon the human system, produces
yellow fever, viz. :
" (a) A volatile inorganic matter.
" (&) A lifeless organic matter of the nature of a fer-
ment, which, by catalytic action, is capable of trans-
forming otherwise (comparatively) harmless substances,
present in the earth or in the atmosphere, into the ma-
teiies morbi of yellow fever.
" (c) A living germ, capable, under favorable con-
ditions as to heat, moisture, etc., of rapid self-multi-
plication, and acting, either directly, or indirectly by
catalytically transforming other substances into the
efficient cause of the disease.
" That the poison is of the latter nature, is, I con-
ceive, the only theory consistent with the observed facts
in regard to the origin and propagation of the disease,
:md upon it all the otherwise contradictory facts are
418 BACTERIA IX INFECTIOUS DISEASES.
reconcilable. In support of this I will first submit a
few concise propositions which seem to me capable of
proof, and will then briefly discuss these propositions,
and the legitimate inferences to be drawn from them :
" 1. The yellow fever poison is not an emanation from
the persons of those sick with the disease.
" 2. It is not generated by atmospheric or telluric influ-
ences. A certain elevation of temperature is, however,
necessary for its multiplication ; and its rapid increase is
promoted by a moist atmosphere, and probably by the
presence of decomposing organic matter.
" 3. The poison is portable in ships, goods, clothing, etc.,
and a minute quantity is capable of giving rise to an exten-
sive epidemic.
" 4. Exposure to a temperature of 32° Fahrenheit com-
pletely destroys it.
" 5. It may remain for an unknown length of time in a
quiescent state, when not subjected to a freezing temper-
ature, or exposed to the conditions necessary to its mul-
tiplication, and may again become active and increase
indefinitely when those conditions prevail.
" If the first three propositions be proven, viz., that
the poison is portable, that a small quantity may in-
crease indefinitely, independently of the human body,
and that it is not produced by atmospheric influences,
then the necessary inference is, that it is capable of self-
multiplication, which is a property of living matter
only."
The propositions above stated were supported, in
the paper referred to, by facts observed during
a local epidemic, which occurred on Governor's
Island, New York harbor, during the summer of
1870. Other local epidemics, since observed by
the writer, and the recorded facts relating to nu-
YELLOW FEVER. 419
merous outbreaks of limited extent, and to the
extended epidemic in the United States in 1878,
followed by a reappearance of the disease in Mem-
phis in 1879, strongly support these propositions,
and the inference drawn from them as to the na-
ture of the yellow fever poison. It will be seen,
however, that our propositions, if accepted as
proven, do not necessarily lead us to the conclu-
sion that the yellow fever germ multiplies within
the bodies of those sick with the disease. On the
other hand, if the first proposition is true, it seems
altogether probable that it does not multiply with-
in the bodies of the sick, but that the poison is
evolved as a result of its vital activity during the
decomposition of the dead organic material which
serves as pabulum for its growth. The observed
facts relating to the epidemic prevalence of the
disease indicate that decomposing animal matter
furnishes a suitable nidus for the germ, and conse-
quently the dead body of a yellow fever patient
should constitute such a nidus, even if the living
body does not. As a matter of fact, infection
has very frequently been traced to dead bodies,
whereas there is abundant evidence to show that
persons contract yellow fever by exposure in in-
fected localities, and not by contact with those sick
with the disease. Bedding charged with organic
emanations from the body of a sick person is also
a suitable nidus for the germ. But the infectious
character of infected bedding seems to be acquired
in infected localities rather than to be due to infec-
420 BACTERIA IN INFECTIOUS DISEASES.
tion by sick, persons. A statement of the evidence
which has led the writer to this conclusion would
be out of place in the present volume, and with-
out further remark we must proceed to consider
the experimental evidence in favor of our a priori
reasoning. It must be admitted that this is very
.unsatisfactory.
The writer's personal investigations are recorded
in the "Preliminary Report of the Havana Yellow
Fever Commission of the National Board of Health,"
extracts from which report are given below. Un-
fortunately, the time allotted to this investigation
— three months — was entirely too short to make
a thorough experimental study ; and much of this
valuable time was necessarily consumed in perfect-
ing methods of research, and in gaining a knowl-
edge of micro-organisms encountered on every side
which rvere not yelloio fever germs, but which could not
be excluded from consideration until this fact was
demonstrated.
Evidently an extended acquaintance with the
bacterial organisms found during life and after
death in the bodies of persons not suffering from
yellow fever, and familiarity with the most ap-
proved methods of isolating and cultivating these
organisms, would have been of great advantage to
the investigator. But this preliminary knowledge
aii'l special training was of the most imperfect
character. It was therefore evident that unusual
scientific caution would be required to compen-
sate, as far as possible, for a lack of previous special
YELLOW FEVER. 421
preparation for the work in hand ; and to avoid
the announcement of pseudo-discoveries which,
when heralded by an enthusiastic but ignorant
explorer, are sure to pass current for a time, inas-
much as a majority of the profession find no time
for personal investigations, and do not realize the
ease with which an explorer in this field of inves-
tigation may fall into a serious error.
Extracts from Report of Havana Commission.
" In Havana, Dr. Sternberg gave a large share of his
time to the microscopic examination and photography
of the blood. No chemical examination was attempted.
The patients from whom specimens of blood were ob-
tained were mostly soldiers in the military hospital of
San Ambrosio. Ninety-eight specimens from forty-one
undoubted cases of yellow fever were carefully studied,
and one hundred and five photographic negatives were
made, which show satisfactorily everything demonstra-
ble by the microscope. These photographs were mostly
made with a magnifying power of 1,450 diameters, ob-
tained by the use of Zeiss's one-eighteenth-inch objec-
tive and Tolles's amplifier. Probably no better lens
than the Zeiss one-eighteenth (oil immersion) could
have been obtained for this work, and it is doubtful
whether any objective has ever been made capable of
showing more than is revealed by this magnificent lens.
With the power used, organisms much smaller than
those described as existing in the blood of charbon or
of relapsing fever would be clearly defined.
" If there is any organism in the blood of yellow fever
demonstrable by the highest powers of the microscope
as at present perfected, the photo-micrographs taken in
422 BACTERIA IN INFECTIOUS DISEASES.
Havana should show it. No such organism is shown in
any preparation photographed immediately after collection.
But in certain specimens, kept under observation in cul-
ture-cells, hyphomycetous fungi and spherical bacteria
made their appearance after an interval of from one to
seven days. The appearance of these organisms was,
however, exceptional, and in several specimens, taken
from the same individual at the same time, it occurred
that in one or two a certain fungus made its appearance
and in others it did not. This fact shows that the
method employed cannot be depended upon for the
exclusion of atmospheric germs, but does not affect
the value of the result in the considerable number
of instances in which no development of organisms
occurred in culture-cells in which blood, in a moist
state, was kept under daily observation for a week or
more.
" The method employed seemed the only one prac-
ticable for obtaining blood from a large number of in-
dividuals without inflicting unwarrantable pain and
disturbance upon the sick. It was as follows: One
of the patient's fingers was carefully washed with a
wet towel (wet sometimes with alcohol and at others
with water) and a puncture was made just back of the
matrix of the nail with a small triangular-pointed trocar.
As quickly as possible a number of thin glass covers
were applied to the drop of blood which flowed, and
these were then inverted over shallow cells in clean
glass slips, being attached usually by a circle of white
zinc cement. In dry preparations, which are most suit-
able for photography, the small drop of blood was spread
upon the thin glass cover by means of the end of a
glass slip.
"The thin glass covers were taken from a bottle
of alcohol and cleaned immediately before using, and
YELLOW FEVER. 423
usually the glass slips were heated shortly before apply-
ing the covers, for the purpose of destroying any atmos-
pheric germs which might have lodged upon them.
These precautions were not, however, sufficient to pre-
vent the inoculation of certain specimens by germs
floating in the atmosphere (Penicillium spores and micro-
cocci) ; and in nearly every specimen the presence of
epithelial cells, and occasionally of a fibre of cotton or
linen, gave evidence that under the circumstances such
contamination was unavoidable. It is therefore believed
that any organism developing in the blood of yellow
fever, or of other diseases, collected by the method de-
scribed, or by any similar method, can have no great
significance unless it is found to develop as a rule (not
occasionally) in the blood of patients suffering from the
disease in question, and is proved by comparative tests
not to develop in the blood of healthy individuals, ob-
tained at the same time and by the same method.
" Tried by this test it must be admitted that certain
fungi and groups of micrococci, shown in photographs
taken from specimens of yellow fever blood collected
at the military hospital and preserved in culture-
cells, cannot reasonably be supposed to be peculiar to
or to have any causal relation to this disease. While
we can claim no discoveries from the microscopic exam-
ination of the blood, bearing upon the etiology of yellow
fever, some interesting observations have been made
relating to the pathology of the blood in this disease.
"It is not intended in this report to do anything more
than make a brief reference to these observations, as a
comparative study of the blood of other diseases will be
required to give value to them, and a detailed report
upon this subject is to be made at some future time.
The most important observation made relates to certain
granules in the white corpuscles shown in many of the
PLATE X.
FIG. 1. — Blood from finger of yellow fever patient in Military
Hospital, Havana, 1879 ; fifth day of sickness ; fatal case. X 400
diameters by Beck's £ inch objective.
FIG. 2. — Blood from finger of yellow fever patient in Military
Hospital, Havana, 1879 ; fifth day ; fatal case. X 1450 ; Zeiss's
^ inch horn, oil im. objective.
FIG. 3. — White blood corpuscle from yellow fever blood of fifth
day, showing fat granules. X 1450.
FIG. 4. — White blood corpuscle from yellow fever blood of fifth
day, showing fat granules. X 1450.
PLATE x.
r IG. 2
YELLOW FEVER. 425
photomicrographs taken. From the manner in which
these granules refract light, and for other reasons, they
are believed by Dr. Sternberg to be fat, and to represent
a fatty degeneration of the leucocytes.
" The blood of twelve healthy individuals was exam-
ined in Havana for comparison, and in nearly every case
an occasional leucocyte was found to contain a few (one
or two) granules undistinguishable from those found in
the blood of yellow fever ; but this was the rare excep-
tion ; while in severe cases of yellow fever the granules
were abundant, and nearly every white corpuscle con-
tained some of them."
The granules referred to are well seen in the
heliotype reproductions of the writer's photo-
micrographs made in Havana. (See Figs. 1, 2,
3, and 4, Plate X.)
Upon comparing the granules referred to, as
seen in Fig. 3, Plate XX, with a photo-micrograph
of the spores of bacilli (Fig. 3, Plate III.) made
with the same amplification, a very striking resem-
blance will be noticed. Indeed it would be impos-
sible to determine from the optical appearances
alone that in one case we are dealing with fat-
granules, and in the other with reproductive spores.
The size and the refractive index are the same, or
very nearly so. These granules were new to the
writer when he first encountered them in the
blood of yellow fever patients, and it seemed not
improbable that a discovery of value had been
made. Much time was accordingly given to their
study. The result of this was to convince the writer
that they were fat-granules, probably developed in
426
BACTERIA IN INFECTIOUS DISEASES.
the leucocytes, and representing a fatty degenera-
tion of their protoplasm, but possibly picked up
from the blood. In the white corpuscle in the
centre of Fig. 2 it will be noticed that these gran-
ules are of various sizes, and that they do not so
closely resemble bacillus spores. The conviction
that they were really fatrgranules was not reached,
however, until after a protracted study of yellow
fever blood, enclosed in germ-proof culture-cells,
which admitted of frequent microscopical exami-
nation of their contents. In these cells no evidence
was obtained that these
granules increase by fis-
sion or grow into rods,
as we should expect if
they were reproductive
bodies. On the other
hand, they increased in
size, became diffluent,
and after a time the leu-
cocyte presented the ap-
pearance of having been
resolved into a little
collection of oil glo-
bules.
The inference that the species of Penicillium (see
Fig. 27) which not infrequently appeared in my
culture-cells was developed from air-borne spores
which accidentally fell upon the drop of blood
during the brief period required for hermetically
enclosing it, and not from spores present in the
Fig 27.
Penicillinm from culture-cell containing
blood of yellow fever patient. X 200.
(Prom photo -micrograph, Havana,
1879.)
YELLOW FEVER. 427
blood prior to its withdrawal from the body, was
probably correct. But it must be admitted that
the argument offered in favor of this view has no
great weight, and that the inference may be a
mistake. The fact that the fungus only appeared
occasionally in my culture-cells would be quite
easily reconciled with its somewhat abundant pres-
ence in the blood ; for an organism of this size
might be present in considerable numbers without
being found in every drop drawn from the ringer.
But direct examination of very many specimens of
blood did not show it, whereas it is well known
that the spores of Penicittium are among the most
numerous of the organized particles suspended in
the atmosphere ; and their abundant presence in
the air of the Military Hospital of Havana was
demonstrated by aspiration experiments and mi-
croscopic examination.
That portion of the Report of the Havana Com-
mission which relates to experiments on animals is
here quoted in full, as one of the objects which the
writer has had in view in the preparation of the
present volume has been to enable those who pro-
pose to enter upon experimental investigations
of this nature to readily avail themselves of the
experience gained by others who have preceded
them :
Experiments upon Animals.
" It has been commonly reported, and is asserted by
several writers of acknowledged ability, that during the
prevalence of yellow fever certain of the inferior ani-
428 BACTERIA IN INFECTIOUS DISEASES.
mals exhibit symptoms of sickness which are attributa-
ble to the influence of the yellow fever poison.
" (Vide Barton, Cause and Prevention of Yellow
Fever, third edition, pp. 52-55 ; Feraud, de la fievre
jaune & la Martinique, p. 271 ; La Roche on Yellow
Fever, Vol. II., pp. 316-318 ; Blair, Yellow Fever Epi-
demic of British Guiana, third edition, p. 63.)
"In view of these reports, the Commission was in-
structed as follows : ' It is obvious that if it be found
possible to produce some specific symptoms in some one
of the lower animals by exposing such animals in local-
ities known to be capable of producing the disease in
man, and thus to establish a physiological test of the
presence of the cause of the disease, we may even hope
to be able to determine the nature of and the natural
history of this cause, although prolonged investigation
may be necessary to effect it.'
"The Commission has endeavored to carry out the
views of the Board of Health in this direction, but in
consequence of the limited time at its disposal, the want
of a suitable place to keep the larger animals, and the
amount of work in other directions expected from it, it
has been found impossible to make an exhaustive exper-
imental investigation. Enough has been done, however,
to make it appear highly probable that the sickness and
mortality reported among animals during the prevalence
of yellow fever epidemics has been improperly ascribed
to the influence of the yellow fever poison. It is well
known that many of the inferior animals suffer from
epidemic diseases peculiar to their several species, and
this is especially the case in southern latitudes. We
know of no reason why such epidemics should not occur
coincidently with yellow fever in man, and it is not sur-
prising that many people nnaccustamed to close observa-
tion should attribute the sickness in man and in the
YELLOW FEVER. 429
animals affected to the same cause. In advance of any
experiments designed to test the truth of such a deduc-
tion, it seemed quite improbable, from the fact that the
supposed effect only results exceptionally, if at all, while
domestic animals are frequently exposed in large num-
bers, in localities visited by severe epidemics of yellow
fever, without exhibiting any symptoms of sickness.
This fact is vouched for by many competent observers,
and is verified by the personal experience of two mem-
bers of this Commission.
14 Nevertheless, in view of the reports referred to, of
the great importance in the prosecution of the investi-
gation of a test of the presence of the poison, and of
the possibility that by close observation and the use of
the clinical thermometer some symptoms heretofore
overlooked might be discovered sufficient to serve as
such a test, it was evidently imperative that experiments
should be tried in this direction. Arrangements were
accordingly made before leaving New York for a supply
of animals as required, and on the 24th of July the
following were received, per steamer ' Niagara,' viz. :
Four dogs, two cats, six rabbits, six guinea-pigs, one
monkey, six chickens, twelve pigeons, and two geese.
Subsequently (August 30) six more dogs were received.
" All of these animals were carefully observed, and
various experiments were tried for the purpose of test-
ing their susceptibility to the influence of the yellow
fever poison. The details of these experiments are
given in a special report to the National Board of Health,
dated October 15. It is not deemed necessary to give
these details in the present report, but the general state-
ment may be made that the results were negative. No
symptoms were produced in any of the animals experi-
mented upon which can fairly be attributed to the
influence of the yellow fever poison.
430 BACTERIA IN7 INFECTIOUS DISEASES.
" The clinical thermometer was constantly used for
the purpose of recognizing any slight febrile movement
which might possibly occur, and the blood was examined
microscopically from time to time. As the experiments
made gave no promise of positive results, the Com-
mission did not feel justified in giving more time to this
portion of the investigation. It is, however, of the
opinion that the reports heretofore referred to, and the
importance of a physiological test of the presence of
the poison would justify the National Board of Health
in pursuing this inquiry in future, especially with such
animals as this Commission has not experimented upon.
A few experiments are here given as examples of those
made :
" Exp. No. 1. — On the morning of July 28, four
days after arrival in Havana, the following animals were
exposed on board the infected brig 4 John Welch, Jr.,'
viz. : two dogs, two cats, one monkey, two rabbits, three
guinea-pigs, two geese, three chickens. The time of
exposure was forty-eight hours, at the expiration of
which time the animals (in cages) were brought back
to the laboratory. The 'Welch ' was a very foul ship,
and was loaded with molasses. During the time the
animals remained on board six of her crew (all) were
down with yellow fever. After bringing the animals
back to the laboratory, the temperature of each was
carefully taken, and daily observations were continued
for some time after. No symptoms of sickness presented
themselves, except in the case of one dog. This animal
suffered a sharp attack of fever, but it is believed that
the case was one of a disease common to imported dogs
in Cuba, known as romadizo, a disease the clinifal history
of which is very different from that of yellow fever.1
1 See special report to National Board of Health, dated October 15, for
full history of this case.
YELLOW FEVER. 431
" Exp. No. 4. — Injected yellow fever blood, one and
a half drachms, of first day, into femoral vein of dog
No. 3. Blood obtained by cupping from patient in civil
hospital and mixed with a small quantity of soda bicarb.,
to prevent coagulation. Result, entirely negative.
" Exp. No. 10. — One-half of a blanket from a yellow
fever patient's bed was placed in the cage with dog
No. 4, and left there for several days. No result.
"• Exp. No. 11. — Dog No. 5 was allowed no water
for two days, except a supply in which the other half
of this blanket (Exp. No. 10) had been washed. No
result."
Other experiments were made, in which the
blood of yellow fever patients, obtained post mortem,
was injected into rabbits and guinea-pigs with
fatal results. But no importance was attached to
these experiments, as several hours had in every
case elapsed after the death of the patient before a
post mortem examination was obtained and the blood
collected. It is well known that putrid blood kills
rabbits, and also that the blood of scarlet fever
and other diseases, obtained post mortem, produces
death when injected beneath the skin of these
animals. Similar results follow the injection of
other material containing the bacteria of putre-
faction, as shown by the following experiment
made in New Orleans at a time when yellow fever
was not prevalent :
Exp. No. 13. — October 7, 9 A. M. — Injected
into right flank of rabbit 1.35 c. c. of water shaken
up with a little material scraped from the surface
of gutter-mud in front of my laboratory. The
432 BACTERIA IN INFECTIOUS DISEASES.
animal was found dead at 8.30 A. M. October 9,
and had evidently been dead some hours. Post
mortem examination shows diffuse cellulitis and
gangrenous sloughing of the integument and sub-
jacent tissues of the right side of the belly. So
extensive has been this sloughing that the intes-
tines are exposed. A very offensive odor of putre-
faction is given off by the gangrenous tissues.
Having reported my own failure to find the
yellow fever germ, I must now refer to the recent
announcements of its discovery in Mexico by Dr.
Carmona, and in Brazil by Dr. Freire. According
to the first-named observer, the parasitic element
is found in the blood, in black vomit, and in the
urine of yellow-fever patients.
The following description is copied from the
"Medical News" of July 21, 1883 :
44 The general agent wanting in none of these sub-
stances is a granular matter, only seen with a micro-
scope of 1,500 diameters, very abundant, ovoid, and
slightly }rellow, which appeared to have filaments similar
to vibrating ciliae, and having peculiar movements, with
a tendency to repeat these again and again. At rare
intervals it curls itself in its greater diameter, and gener-
ally arranges itself on its side, gradually approximating
the extremities until they meet ; then it regains its
ovoid form, which is similar to that of the prostate
gland. These granulations are capable of increasing or
maturing, and, under special conditions, gradually lose
their first movement, and then unroll themselves into
spherical bodies of yellow color, uniform aspect and
dimensions, eight or ten times larger than the first
YELLOW FEVER. 433
granulations. These are from 5 to 12 /x in diameter.
These large granulations were those which first attracted
attention in the urine of the patients first examined, and
since found in the cellular tissues, serum of blisters,
and other points of the organism. There were in the
urine threads, evidently mycelia, — some so large as to
cover the whole field of view, others smaller ; and,
besides, there were abundant fragments, of various forms
and dimensions. Some were more delicate and of a
cellular aspect ; others more compact and larger, of a
brilliant yellow color and of fatty aspect ; some of
a more reddish color ; others emerald green ; still others,
but much more rare, of a blue color. Their diameters
varied from 2 to 20 /*. Cells were frequently encountered
completely empty, of rounded or pyriform shape and
variable dimensions. Many of these cells were not entirely
empty, but contained a red or yellow granular material,
similar to the points observed in the gold-stone."
The writer has ventured to italicize this descrip-
tion of these partially empty cells, as it recalls to
his mind a story told him by his friend, Dr. J. J.
Woodward, of the United States Army, whose skill
as a microscopist is pretty generally recognized,
both in this country and in Europe.
Dr. Woodward states that several years since a
distinguished (?) professor from one of the Western
cities came to Washington to show him the germ
of malarial fever which he had recently discovered.
An examination of his specimens showed that the
supposed alga (cryptococcus) was nothing more nor
less than the little depressions in the surface of the
glass slide upon which his material was mounted,
28
434 BACTERIA IN INFECTIOUS DISEASES.
filled with the grains of rouge powder used by the
manufacturers for polishing these slides. These
little crypts, partly filled with grains of red or
yellow rouge powder, are very abundant on the
surface of some glass slides.
And this recalls a mistake made by the writer
soon after his arrival in Havana in 1879. Upon
aspirating the air in front of my laboratory through
a small aperture, against a thin glass cover smeared
with glycerine, and examining this with a high
power (Zeiss T^ in.), it was found that a variety
of particles of considerable size, such as pollen
grains, spores of PemcOtium, starch grains, etc., had
been arrested ; and also that the specimen con-
tained a large number of spherical and rod-shaped
bodies, which were supposed to be bacteria. A
few days later, upon examining specimens of yel-
low fever blood spread upon thin glass covers,
similar bodies were discovered. Photo-micrographs
were made, which showed these minute spherical
and rod-like bodies interspersed among the blood-
corpuscles ; and distinguished physicians, who have
since inspected these photographs, have supposed,
before hearing an explanation of their real nature,
that they were really bacterial organisms. This
was my own opinion when I first saw them, but I
noticed that they did not seem to be in exactly
the same focal plane as the blood-corpuscles. I
therefore resorted to the simple expedient of wash-
ing the blood from the cover-glass and remounting
this over a circle of cement. Upon now examin-
YELLOW FEVER. 435
ing it with the same power, I found that while the
blood-corpuscles had disappeared, these pseudo-bac-
teria still remained, — showing that they were at-
tached to or imbedded in the thin glass cover. I
have since examined numerous glass covers that
had been thoroughly cleaned by means of nitric
acid, first, and distilled water or alcohol afterwards,
and not infrequently I have found these same
objects, which are only to be seen by the use of
high powers.
But this is perhaps an unwarrantable digression,
and I proceed to quote from the author mentioned :
" These same elements were found in the vomited
matter, having a white or greenish-yellow color, being
especially abundant in large mycelial threads. In some
cases there were ovoid cells, which appeared to be
due to the alcoholic fermentation described by Pasteur.
In these liquids, the spherical, yellow and elementary
granules suffered the same changes as already noticed
in the urine. The black vomit sediment appeared to be
formed for the greater part of blackened mycelial threads,
and other bodies of different forms and sizes, also black.
There were also present yellow or greenish threads and
elemental granules."
To this fungus of many forms and many colors
the discoverer has given the name " Peronospera
Mea."
The writer failed to find anything corresponding
with this description in his examinations of blood,
urine, and black vomit, while in Havana, but reports
as follows :
436 BACTERIA IN INFECTIOUS DISEASES.
" Organic fluids, such as urine, black vomit, arid the
fluid from the interior of unripe cocoanuts, exposed in
the laboratory, very soon became filled with a variety
of vegetable organisms, bacteria, torulse, vibriones, and
other fungi, such as are found under similar circum-
stances in all parts of the world. Most of these were
well-known arid common forms ; some may have been
peculiar to the latitude or even to localities infected
with yellow fever, but to decide this question would
require a more precise knowledge in regard to these
low forms of vegetable life than was possessed by any
member of the Commission, or, indeed, than is likely to
be found even among those who have devoted the most
attention to this branch of study, which is acknowledged
by all to be yet in its infancy.
" Photo-micrographs were made of some of these forms,
and it is suggested that photographic representations of
all forms found in southern parts of the United States at a
time when yellow fever does not prevail, should be made
in advance of the next epidemic, so that any unusual
form presenting itself then may receive the special
attention of future investigators " (I. c.).
In the first edition of this work (Fig. 4, Plate II.
and Figs. 1 and 2, Plate III.) photographs from
nature are given of some of the organisms which
were found most abundantly in yellow-fever urine.
It may be that one of these, or some one of the
many organisms which Carmona has included in
his description, is the veritable germ of yellow
fever ; but this is a mere hypothesis, not supported
by the slightest evidence. At the time of my
visit to Havana I had not perfected my method of
conducting culture experiments (see p. 178), and
YELLOW FEVER. 437
if I had been fully prepared for the work, could
not have found the time to obtain pure cultures
of each micro-organism encountered, and to make
inoculation experiments for the purpose of deter-
mining whether any one of them had specific
pathogenic properties. Pasteur was engaged for
several years in his study of pebrine, the parasitic
disease of silkworms -upon which he may be said
to have founded his scientific reputation. That the
etiology of yellow fever was not worked out during
the three months' stay of the Havana Commission
in Cuba cannot therefore appear surprising to
those who know the difficulties of such an under-
taking; and if Dr. Carmona, or Dr. Somebody-else
succeeds in carrying off the laurels due to a dis-
coverer, it will be rather a matter of luck than of
science, unless he attacks the problem by the
painstaking and timetaking methods which have
been perfected by Pasteur, Koch, and other pio-
neers in this line of investigation. Dr. Carmona
says :
" If a portion of urine be allowed to evaporate spon-
taneously, and the residue be examined microscopically,
the protoplasmic substance containing abundant spheri-
cal yellow granulations, mycelial tubes, and crystals of
cholesterine and tyrosine, before mentioned, are seen.
The free extremities of many of the mycelial threads
were gradually dilated, somewhat resembling the ex-
tremity of the olfactory bulb." These dilated extrem-
ities Carmona calls oogonos, and they measure from
10 to 60 fj..
Yellow fever urine is an acid albuminous fluid,
438 BACTERIA IN INFECTIOUS DISEASES.
and a suitable culture-medium for a variety of bac-
terial organisms and microscopic fungi. At the
extremity of the urethral canal, bacteria are always
found in considerable numbers, and the urine of
healthy persons, or of yellow fever patients, is
necessarily contaminated with these when it is
voided. Urine " allowed to evaporate spontane-
ously" is presumably exposed to the air and to
inoculation with the numerous germs which it
contains.
Dr. Carmona says : " The black vomit sediment
appeared to be formed for the greater part of
blackened mycelial threads, and other bodies of
different forms and sizes, also black."
The uniform testimony of competent micro-
scopists who have heretofore examined black
vomit is, that the dark color is due to the presence
of blood, altered by the acid secretions of the
stomach, which escapes from the hypersemic mu-
cous membrane during the later stages of the
disease, when passive hemorrhages are common.
The writer has repeatedly verified this fact, and,
while in Havana, made photo-micrographs, which
show that the little dark-colored flocculi in the
vomited material are made up of decolorized blood-
corpuscles and of amorphous masses of dark ma-
terial which is presumably haemoglobin from these
decolorized corpuscles, changed by the acid secre-
tions of the stomach. A microscopic examination
of black vomit or of the transparent acid fluid
ejected at frequent intervals before hemorrhages
YELLOW FEVER. 439
occur, shows that it contains epithelium from the
mouth and bacteria of various forms. This is not
surprising when we remember that every drop of
saliva swallowed is charged with a variety of these
minute plants. To decide whether any one of
these bears a causal relation to the disease, would
require extended culture-experiments, and the
administration of a pure culture to man himself, as
a test of specific pathogenic power, unless satis-
factory evidence can be obtained that some one of
the lower animals is susceptible to the disease.
A more recent claim to the discovery of the
yellow fever germ is that made by Dr. Freire of
Brazil.
I quote again from the " Medical News " (July
7, 1883, p. 13):
" Dr. Freire recognizes in the blood of yellow fever
patients a cryptococcus to which he has given the specific
title of Xanthogenicus. In the phases of its development
it appears as minute points, or as large round cells with
grayish or fringed margins, and bright transparent
centres. Besides these there are occasionally seen trans-
parent granulations, aggregated in a yellowish matrix.
A gramme of blood charged with these organisms, from
a yellow fever patient, was injected into the veins of a
rabbit, which died in a quarter of an hour with tetanic
convulsions. ... At the autopsy visceral congestions
were found, similar to those seen in persons dead of
yellow fever, and the blood was found to contain the
cryptococcus which was present in that which had been
inoculated.
" A gramme of the blood of this rabbit was injected
440 BACTERIA IN INFECTIOUS DISEASES.
hypodermically into a guinea-pig, which died at the end
of some hours. Its blood was found to contain an ex-
traordinary quantity of the cryptococcus. A second
guinea-pig was inoculated by hypodermic injection with
the blood of the first one, and after some hours the
animal appeared feverish and oppressed, with cold ears
and paws, trembling, and blackish vomiting. It died in
a short time, and its blood showed an infinity of the
characteristic organisms.
" Dr. Freire considers that these experiments estab-
lish the parasitic nature of yellow fever, arid that the
parasite C. Xanthogenicus, is found in every undoubted
case of the disease. He has also discovered and is-
olated the alkaloid from the black vomit, which he
regards as a product or excretion of the microbes. He
considers that the color of black vomit is not due to
altered blood, but to the cryptococcus. He regards
cemeteries as perennial foci of the disease. Some earth
was taken from the grave of a man who had been buried
a year before. A guinea-pig shut up in a confined
space with this earth died in five days. Its blood was
literally crammed with the cryptococcus in various stages
of evolution ; its urine was albuminous, and its brain
and intestines yellow with the peculiar pigment of the
microbe."
The writer is not prepared to estimate the value
of the evidence here offered, inasmuch as we are
not informed whether the yellow fever blood used
in the first inoculation experiment was obtained
post mortem or ante mortem. It would be interesting
also to know whether the cryptococcus was ob-
tained in blood drawn with proper precautions
during the lifetime of the patient. While in
YELLOW FEVER. 441
Havana, the writer paid very little attention to
post mortem blood ; but it was noticed that in blood
drawn during the last hours of life the seritm was
tinted yellow, and the red corpuscles were paler
than normal from a loss of haemoglobin. Any
albuminous granular material in post mortem blood
— from disintegration of the corpuscles, etc. —
would therefore be likely to be stained yellow by
this pigment
Hineman, a very competent German physician
practising in Vera Cruz, has not been more success-
ful than the writer in finding the Peronospera lutea of
Carmona, or the Cryptococcm Xanthogenicus of Freire,
in the blood of yellow fever patients, before death.
He examined the blood of patients in the last
stage of the disease, taking blood from the hand,
thinning it with artificial serum, and brine/ing it at
once under the microscope. He says : " In nine
cases so examined not the slightest deviation from
normal blood could be found. . . . No organisms
were found.'* *
i Arch. f. path. Anat. LXXVIIL p. 139.
PAET SIXTH.
BACTERIA IN SURGICAL LESIONS.
THE important part played by bacteria in sur-
gical lesions can no longer be questioned. This
is demonstrated (a) positively, by the ill-effects
which result from the retention of discharges con-
taining putrefactive bacteria upon the surface of
open wounds, or in sinuses and cavities; and (b)
negatively, by the favorable results of antiseptic
treatment ; and the fact that when .the access of
micro-organisms is prevented by the integrity of
the cutis, very severe lesions, attended with an
abundant exudation of bloody serum, are, com-
monly recovered from without suppuration or any
evil result from the resorption of this fluid and of
inflammatory exudates. But this same material
quickly attains poisonous properties in the presence
of bacteria, and not only exercises a deleterious
local effect, unfavorable to the repair of the injury,
but its absorption now is attended with the most
serious consequences.
These facts, which are so generally recognized
that it is unnecessary to present evidence in their
BACTERIA IN SURGICAL LESIONS. 443
support, are in accord with the following propo-
sitions which have been established by experimental
research and may be accepted as fundamental
truths upon which to base our reasoning as regards
the role of the bacteria in surgical lesions.
(a) The blood and tissues of healthy persons do
not, under ordinary circumstances, contain bac-
terial organisms.
(b) Putrefactive decomposition of organic fluids
is due to bacterial organisms.
(c) Albuminous fluids, — e.g., blood and pus,
which have undergone putrefaction, contain a
potent poison, or poisons, which, in comparatively
small amount, may produce death in the lower
animals.
We have here a sufficient foundation for the
antiseptic treatment of wounds. But in addition
to this there are strong reasons for believing that
certain species of bacteria have also the power
of invading the tissues, and producing local necro-
sis, when for any reason the vital resistance of
these tissues is reduced, — e, g., from hemorrhage,
from starvation, from crowd poisoning, from septic
poisoning. Or the same result may perhaps occur
when the vital resistance of the tissues is not below
par, in consequence of the unusual vigor of the
micro-organisms, developed as a result of unusually
favorable conditions of environment. As, for ex-
ample, when a healthy man, recently wounded,
fulls a victim to hospital gangrene as the result
of infection in a crowded ward, in which this in-
444
BACTERIA IN SURGICAL LESIONS.
Fig. 28.
factious disease was in the first instance developed
de novo.
The purulent discharge from wounds not treated
antiseptically always contains micro-organisms.
These are mainly micro-
cocci and short rods like
those shown in Figs. 28 and
29, which are copied from
Cheyne's recent work on
"Antiseptic Surgery."
The micrococci repre-
sented in Fig. 28 were ob-
tained by cultivation in cu-
cumber infusion, from a
wound treated asept'cally.
The orga™sms represented
in Fig. 29 are from a case
of compound dislocation of the thumb not treated
aseptically. The rod-bacteria in this figure are
doubtless septic bacteria, properly so called, which
give rise to the putrefactive decomposition of albu-
minous fluids. The observations of Cheyne show
that these may be excluded from the secretions of
wounds by antiseptic treatment, and that, in this
case, the pus discharged from such wounds pre-
sents no evidence of putrefaction, although, in
certain cases, micrococci are found in this pus
formed beneath antiseptic dressings. This is ex-
plained by the greater resisting power of micro-
cocci to antiseptic agents. Cheyne says :
" Micrococci prefer acid fluids ; most bacteria prefer
alkaline or neutral fluids.
BACTERIA IN SURGICAL LESIONS.
445
" Micrococci grow, readily, in fluids containing pro-
portions of carbolic acid in which bacteria only grow
with difficulty" (Z. <?., p. 244).
The experiments of the writer have not shown
any difference as regards
the action of carbolic acid
in preventing the develop-
ment of these different or-
ganisms in culture-fluids ;
but in the case of boric acid
and of sodium biborate a
very marked difference was
observed, the micrococcus
of pus developing freely in Specimen of discliarge taken from a
the presence of 0.25 per case of compound dislocation of
the thumb not treated asepti-
cent of boric acid, while B. caljy- x 1450. (From cheyne's
. " Antiseptic Surgery.")
termo failed to develop in
the presence of one-half this amount. It is pro-
bable that free access of oxygen in the culture-
experiments, and its exclusion, to some extent at
least, from the surface of wounds treated anti-
septically by Lister's method, is an advantage in
favor of the micrococcus in the latter case ; for we
know that this may multiply freely in the absence
of oxygen in the pus of a closed abscess.
While there is no question as to the injurious
effects of putrefactive bacteria in the discharges
from wounds when these are retained upon an
absorbent surface, or in a sinus or pus-cavity, the
role of the micrococcus of pus has not been so
well established. According to one view, inflamma-
Fig. 29.
446 BACTERIA IN SURGICAL LESIONS.
tion results in the formation of pus only when
this micrococcus is present, and because of its
presence. On the other hand, it has been claimed
that it is simply present because it finds in pus a
suitable culture-medium, and that its presence in
this fluid is without significance. Cheyne is in-
clined to look upon this micrococcus as compara-
tively harmless; and without doubt it may be
present in the pus secreted by wounds which are
healing in a most satisfactory manner. Cheyne
says :
"It is certain that they do not cause putrefaction,
but they always cause a sort of sour, sweaty smell in
fluids, — a smell which can be recognized in whatever
fluid they grow : in other words, they are associated
with a peculiar fermentation. Now, the products of
this fermentation are but little irritating. They have
no acrid taste, nor do they feel pungent when applied
to a cut surface. Hence, probably, it is that we find
wounds in which these organisms exist, even in large
numbers, appear often unaffected by their presence.
" Nevertheless, they can hardly, under any circum-
stances, be indifferent, and I think I have observed that
in some cases, after they have got in, the wounds do
not behave quite as typically as usual ; i. e., there may
be a trace of suppuration, or a sinus takes longer to
heal than one had any reason to expect."
To test the possible local pathogenic action of
the micrococcus of pus the writer made the follow-
ing experiment :
" Exp. No. 12. — August 4. — An incised wound was
made with scissors, removing a fragment of skin upon
BACTERIA IN SURGICAL LESIONS. 447
each thigh of a half-grown rabbit. The wound upon
the right thigh was moistened with a culture-fluid
(twentieth culture) containing the micrococcus from
gonorrhoeal pus. The wounds were then dressed with
dry tow, and a bandage applied. Both healed kindly
without any undue inflammation, and no difference was
observed between the two."
This single experiment counts for but little ; and
the criticism may be made that this micrococcus
was obtained from gonorrhceal pus, and is perhaps
specifically distinct from the micrococcus of ordi-
nary pus, although it appears to be morphologically
identical with it. All this is admitted, and the
experiment is introduced mainly to call attention
to a method, which, carefully applied, should
enable us to solve the question as to the patho-
genic role of this micrococcus. The writer had
mapped out for himself a series of experiments in
this direction and many others relating to etio-
logical questions, but circumstances have not been
favorable for the prosecution of experimental work,
and he finds himself, somewhat reluctantly, en-
gaged in a review of the field, when it would be
far more to his taste to interrogate nature by the
experimental method, and thus to aid directly in
the solution of these interesting problems.
One of these problems, with our present light,
is very puzzling. It has been demonstrated by
numerous observers that this micrococcus of pus is
uniformly found in pus obtained from an acute
abscess, when the integument covering it is still
448 BACTERIA IN SURGICAL LESIONS.
intact, even when it is deeply situated in the
tissues ; and yet the observations of Pasteur, Koch,
Cheyne, and many others, are in accord as to the
absence of all micro-organisms from the blood of
healthy persons. Whether, then, we suppose this
micrococcus to be the cause or the result of the for-
mation of these abscesses, we are met by the ques-
tion, How did it get there in the first instance ?
In certain cases such abscesses may be traced to
an injury in which a slender, sharp-pointed in-
strument — e. g., a needle or a thorn — has pene-
trated deeply into the tissues ; and in this case we
may suppose that micrococci have been introduced
in this way. Or possibly the point of inoculation
may have been far removed from the situation
where the abscess is developed, and the organisms
may have made their way in the blood-current or
through the lymphatics to this point, where, for
some mechanical reason, they have been arrested.
But this is speculation, and we must leave the
question unsettled, and content ourselves for the
present with a summary statement of the observed
facts relating to the presence of this micrococcus
in collections of pus not exposed to the air.
In 1875, Bergeron, in a communication to the
French Academy of Sciences, reported, as the re-
sult of numerous observations made for the pur-
pose of ascertaining if the pus of abscesses contains
bacteria, as follows :
" 1. Vibrios are found in the pus of abscesses, with-
out any contact with the external air, and without,
BACTERIA IN SURGICAL LESIONS. 449
usually, any indication that the organism is seriously
affected by their presence. 2. We cannot admit that in
these cases the vibrios have penetrated into the interior
of the abscess through the lymphatic system, or through
the circulating system, both being intact. The pus of
warm abscesses in adults often contains vibrios ; if they
occur in the case of infants the fact has not been ob-
served. 3. The pus of cold abscesses in the adult, as in
the infant, never contains them." (Magnin.)
The vibrios of Bergeron are doubtless identical
with the micrococcus described by later observers,
which often occurs in chains. The observations of
Billroth, Cheyne, and Ogston, are in accord with
those of Bergeron as to the presence of micrococci
in acute abscesses, and their absence from chronic
abscesses. Cheyne has shown, however, that when
these organisms are proved to be present in pus
from an abscess, by microscopical examination, this
pus often fails to fertilize a culture-fluid, thus
proving that the micrococci are no longer living.
He says:
" Of acute abscesses, I had up to May, 1879, inocu-
lated from thirty-two cases. In twenty-five of these no
growth of organisms occurred, while from six micro-
cocci were obtained. In no case did I get bacteria "
(1. c., p. 253).
Ogston examined the pus from eighty-two ab-
scesses, all of which had been "hitherto unopened."
The pus was taken from them by means of a needle
or a knife while still flowing from the incision,
spread out in a thin film upon a slide, immediately
29
450 BACTERIA IN SURGICAL LESIONS.
dried, and stained with an aniline dye. Of the
abscesses examined, thirteen were —
" Chronic typical cold abscesses, whose duration could
be measured by months, proceeding from chronic carious
disease of bone, scrofulous lymphatic glands, and such
like. In none of them were any organisms found.
" Four were somewhat chronic abscesses, whose dura-
tion could be measured by weeks ; and which had fol-
lowed diseases more or less allied to, or complicated
with, forms of blood-poisoning and hectic, such as tonsil-
itis, phthisis, scarlatina, erysipelas, typhoid fever, and
diphtheria. All of these contained micrococci, and were
evidently the same as the next form.
" Lastly, sixty-five were acute abscesses, whose dura-
tion could be measured by days, from all parts of the
body. Every one of these contained micrococci."
The cocci were found (a) in chains, usually of five
or six elements, but often much longer — in one
case three hundred and twenty-one cocci were
counted in a single chain ; (b) in groups, " like the
roe of a fish" — zoogloea masses; (c) in groups of
three or four, " many of which were clearly, from
the equal size and relative positions of the cocci,
formed by a direct division into fours, or even,
though more rarely, into threes ; " (d) in some
cases unusually large oval cocci were found, chiefly
in pairs. " For the most part these varieties ex-
isted in separate abscesses, but it frequently
occurred that an abscess contained both chains and
groups. Out of sixty-four abscesses where this
point was specially noted, seventeen contained
BACTERIA IN SURGICAL LESIONS. 451
chains only, thirty-one groups only, and sixteen
both forms, or only pairs."
Ogston was unable to discover any difference in
the character of the abscesses which contained
these different forms, and could not decide defi-
nitely whether they represented different species
or only varieties of the same species.
To ascertain whether these micrococci possessed
pathogenic properties, Ogston injected pus con-
taining them into guinea-pigs and mice ; and, for
comparison, pus from cold abscesses, which con-
tained no micro-organisms, into other animals of
the same species.
The invariable result of twenty experiments, in
which pus from the last-mentioned source was
used, was that no illness or abscess ensued.
" But a very different effect was produced when
similar injections were made with pus containing micro-
cocci. In every instance, with the qualifications to be
presently made, well-marked disease was set up. Quan-
tities, varying from one to three minims, produced, in
the animals already mentioned, symptoms of blood-
poisoning, lasting from two to five days. . . . These
symptoms became less marked towards the end of the
first week or five days. If the animal was killed during
this stage, the blood in its right heart was found to con-
tain micrococci ; single, in pairs, and in short chains of
six or fewer, swimming in the serum between the cells.
Around the site of injection was found a patch of red
infiltration, varying in size, and having in its centre
more pus than corresponded with the quantity that had
been injected. The pus contained myriads of micrococci
452
BACTERIA IN SURGICAL LESIONS.
of the same nature as those injected, but more numer-
ous. . . . The cocci were living and growing, and a
drop of the matter injected into another animal pro-
duced the same results in it, and it on another animal,
and so on. No increased virulence was observable in
the transference through a series of animals. The red
infiltration around the abscess showed the micrococci
invading the neighboring tissues, penetrating between
their cells, and in colonies or chains, gradually decreas-
Fig. 30.
Group of chain micrococci in pus. x 1600 (Ogston.)
ing in size, pushing their way for a considerable distance
into the structures in the vicinity. . . . After five to
seven days had elapsed, and in some cases even earlier,
the animals exhibited a change. They became more
active again, threw off their lethargy, and seemed well ;
but at the spot where the injection had been made, there
was found a fluctuating tumor, gradually increasing in
size, and presenting all the signs of being an ordinary
abscess. When they were killed during this second
stage, micrococci were more rarely found in the heart-
BACTERIA IN SURGICAL LESIONS. 453
blood, and the infiltration of the organisms into the
tissues around the abscess no longer existed, having been
replaced by a firm, thick wall of granulation tissue, in
which micrococci could seldom be detected, and which
seemed to act as a barrier, preventing or diminishing their
migration into the blood and surrounding structures. . . .
44 On the presumption that carbolic acid would de-
stroy the power of the micrococci, a series of injections
were instituted with pus mixed with equal parts of a
five per cent watery solution of that substance. These
were employed on separate animals, as well as on a
different part of an animal injected with unmixed pus
from an acute abscess ; and in every case, the pus so
disinfected, though injected in larger quantity, produced
no reaction whatever, but disappeared in the rapid and
complete way described under the experiments with that
from cold abscesses.
"I next endeavored to ascertain the temperature
capable of destroying the power of micrococci. Although,
in this direction, the experiments were not so numerous
as is desirable, it may be stated that pus heated to
130° Fahr., or higher, hitherto always failed to excite
suppuration."
This is strong evidence in favor of the view that
the formation of acute abscesses is due to the
presence of this micrococcus. The writer has shown
that its thermal death-point is 140° Fahr., the
time of exposure being ten minutes. Ogston does
not state the time of exposure to a tempera-
ture of 130° Fahr., but it may well be that a
somewhat longer exposure than ten minutes at
this temperature would also be fatal to the mi-
crococcus.
454 BACTF/HIA IN SURGICAL LESIONS.
Ogston made also a large number of culture-
experiments.
u As might have been anticipated, cultivations of pus
of cold abscesses (five cases) yielded uniformly negative
results.
" Cultivations of pus of acute abscesses gave at first
the most inexplicable and contradictory results. This
was ascribed to the fact that the micrococcus in question
is anagrobie, and cannot grow in the presence of oxygen.
The plan was therefore tried of growing them in eggs.
Newly-laid eggs were washed in five per cent carbolic
water ; and, under spray, a minute aperture was pierced in
the larger end. One minim of pus from an acute abscess,
collected under the strictest antiseptic precautions, was
injected by a long-pointed pure syringe into the albumen
at the opposite end of the egg. A piece of protective
was laid over the aperture. The egg was enveloped in a
Lister's dressing, and kept for ten days in the incubator
at 98° Fahr. At the end of that time it was opened,
and my expectations were fulfilled. The egg was sweet
and fresh ; its contents were unaltered, save the yolk
was somewhat broken up, and more or less mixed with
the albumen ; but the albumen, and sometimes the yolk
also, were filled with enormous chains or masses (accord-
ing to the sort of coccus used) of micrococci, growing
quite as luxuriantly as I had ever observed them when
expeiimenting on animals. A drop of the albumen in-
jected into an animal's back now produced typical
abscess, with all the symptoms already mentioned ; and
the animal, on being killed, showed the micrococci in
the blood and invading the tissues, exactly as had been
already obtained by the employment of the pus of acute
abscesses."
This is an extremely interesting experiment,
BACTERIA Itf SURGICAL LESIONS. 455
but Ogston is evidently mistaken in ascribing the
contradictory results at first obtained to the fact
that the micrococcus in question is anaerobic ; for
while this is true, and it can doubtless grow in the
absence of oxygen, the writer has found no diffi-
culty in cultivating it through successive gener-
ations, in the culture-flasks described on page 177,
in bouillon made from the flesh of a rabbit or of a
chicken, and in the presence of atmospheric air,
with which these flasks are two-thirds filled when
prepared in the manner indicated. Thus, in my
experiments upon the germicide power of various
therapeutic agents, a pure-culture of this micro-
coccus was maintained through many successive
generations, culture No. 1 having been inoculated
with a drop of pus from a whitlow, obtained at the
instant of its escape from a deep incision. The
true explanation of the contradictory results ob-
tained by Ogston is doubtless that given by Cheyne,
viz. : that when no development occurred in cul-
ture-solutions inoculated with the pus of acute
abscesses, it was because the micrococci were
already dead. Wernich has shown that during
the multiplication of various bacterial organisms
in a limited amount of nutritive pabulum, chemical
products are evolved fatal to the vitality of these
organisms.
In conclusion, the writer would suggest that
those who desire to make themselves familiar with
the organisms to which a pathogenic role has been
456 BACTERIA IN SURGICAL LESIONS.
ascribed, and with the technique relating to their
recognition, cultivation, etc., will do well to com-
mence with this micrococcus of pus, a pure culture
of which may be easily obtained in the manner
heretofore indicated.
BIBLIOGRAPHY.
ALBRECHT, R. — Beitrag zur Kenntniss und Entwicklung der
Spirochaete Obermeieri. Deutsclies Arch. f. Klin. Med., Leipz.,
1881. XXIX. 77-112.
ALMQUIST, E. — Tyfoidfeberns bakterie. Nord. med. Ark., Stock-
holm, 1882, XIV. Xo. 10, 1-31, 1 pi.
. Method of cultivating and coloring bacteria. Hygeia,
Stockholm, 1883, XLV. 220-262.
ANDRAL and GAVARRET. — Recherches sur le mode et les circon-
stances de developpement d'un vegetal microscopique dans les
liquides albumineux, normaux et pathologiques. Gaz. med. de
Par., XI. 87-91. 1843.
ARLOIXG, CORXEVIX, et THOMAS. — Sur 1'inoculabilite du charbon
symptomatique et les caracteres qui le differencient du sang de
rate. Compt. rend. Acad. d. sc., Par., 1880, XC. 1302-1305.
. De 1'inoculation du charbon symptomatique par injection
intra-veineuse, et de 1'immunite conferee au veau, au mouton et
a la chevre par ce procede. Compt. rend. Acad. d. sc., Par., 1880,
XCL 734-736.
Sur la cause de 1'immunite des adultes et de 1'espece bo-
vine centre le charbon symptomatique ou bacterien, dans les
localites oil cette maladie est frequente. Compt. rend. Acad. d.
sc., Par., 1881, XCIII. 605-6UU.
Mecanisme de 1'infection dans les differents modes d'ino-
culation du charbon symptomatique; application a 1'interpreta-
tion des faits cliniques et a la methode des inoculations preven-
tives. Compt. rend. Acad. d. sc., Par., 1881, XCII. 1246-1248.
Nouvelles recherches experimentales sur la maladie infec-
tieuse appelee charbon symptomatique. J. de med. vet. et de
zootech., Lyon, 1881, 3. s., VI. 290-300.
. Experiences publiques sur la vaccination du charbon
symptomatique. Arch, vet, Par., 1881, VI. 721-727.
. Note relative k la conservation et a la destruction de la
virulence du microbe du charbon symptomatique. Rec. de med.
vet. Par., 1882, 6. s., IX. 467-472.
Moyen de conferer artificiellement 1'immunite contre le
charbon symptomatique ou bacterien avec du virus attenue.
Compt. rend. Acad. d. sc.. Par., 1882, XCV. 189-191.
Le charbon symptomatique; troisieme rapport a M. le
Ministre de 1' Agriculture sur le resultat des inoculations preven-
tives. Arch, vet., Par., 1882, VII. 767-771.
458 BIBLIOGRAPHY.
ARLOING, CORNF.VIN, et THOMAS. — Modifications que subit le
virus du charbon symptomatique ou bacterien sous 1'influence de
quelques causes de destruction. Compt. rend. Soc. de biol.,
Pur., 1883, 7. s., IV. 121-128.
ARXDT. — Observations on Spirochcete denticola. The Spirochaete of
the Mucus of Teeth. Arch. Path. Anat. and Physiol. LXXIX.
76-86. 1880.
AKNDT, R. — Untersuchungen liber die Entstehung von Kokken und
Bakterien in organischen Substanzen. Arch. f. path. Anat.,
etc., BerL, 1880, LXXXII. 119-146, 1 pi.
BABES, V. — Pathogenous Bacteria. Biol. Centralbl., II. (1882)
97-101.
BANTI, G. — De la pneumonie infectieuse. [Memoire lu a la soc.
med.-phys. de Florence, le 10 Mars, 1879, traduit par E. Vais-
soii.] Arch. gen. de med., Par., 1880, CXLVI. 36--15.
BASTIAX. — Upon the Conditions which favor Fermentation and
the Appearance of Bacilli and Micrococci in Liquids previously
boiled. Journ. of the Linn. Soc. Zool., XIV. 1875.
. Bearing of Experimental Evidence -on the Germ Theory
of Disease. Brit. Med. Journ., 1878, Vol. I. 49. 1878.
BAXTER. — The Action of the Cinchona Alkaloids and some of
their Congeners on Bacteria and colorless Blood-corpuscles.
Practitioner, Lond., XI. 321-351. 1873.
B^CIIAMP. — Sur les microzymas de 1'urine. Montpellier medical.
1874.
. Discussion sur les urines ammoniacales. Bull. Ac. de
med., 20 Jan., 1874.
. Sur les microzymas et les bacteries. Montpellier medi-
cal. 1875.
. Les microzymas au point de vue physiologique et patho-
logique. Tr. Internal;. M. Cong., 7. sess., Lond., 1881, I. 352-374.
Role and Origin of some Microzymes. Compt. rend.
Acad. d. sc., XCII. (1881) 42-44.
— . Sur les proprietes et les fonctions des microzymas pan-
creatiques. Bull. Acad. de med., Par., 1881, 2. s., X." 630-663.
Les microzymas sont-ils des organismes vivantes. Exposi-
tion d'une theorie experimentale de Pantisepticite. Bull. Acad.
de med., Par., 1882, 2. s., XI. 497-547.
. Les microzymas et les zymases. Arch, de physiol. norm.
et path., Par., 1882, XIV. 28-62.
BECK, M. — Report to the Pathological Society of London by the
committee appointed " to investigate the nature, causes, and pre-
vention of those infective diseases known as pyaemia, scptica'inia,
and purulent infections.'* Rep. Med. Off. Local Gov. Bd.,
1879, Lond., 1880, IX. 207-358, 11 pi.
l)i 1.1 IKLD, W. T. — On the relations <>f micro-organisms to disease.
Med. Rec., N. Y., 1888, XXIII. 107, 225.
lii M — An Account of the Recent Researches into the History of
the Bacteria, made bv ami umlcr tin; Direction of Prof. Colin.
Quart. J. Mirr. Sc . Loud., XVI. 25!l -278, 1 pi. 1875.
Li. I'.I.L. — The bacillus of measles. Brit. Med. Journ., Jan. L'7,
1888.
BIBLIOGRAPHY. 459
BERGMANX. — Das putride Gift und Putride Intoxicat. Dorpat,
1868.
BERGOXZIXI, C. — I Bacteri. Studii critici sperimentali. Spallan-
zani, Modena, 1879, VIII. 289-296; 349-355; 443-153.
. New Colored Bacterium. Ann. Soc. Nat. Modena, XIV.
(1880) 149-158.
BERT, PAUL. — Experiences sur la Bacteridie. Soc. de biologie.
1875.
. Anaerobies. Compt. rend. Acad. d. sc., 1878.
. Experiments on the Blood of Anthrax. Compt. rend.
soc. de biol., Paris, XXIX. 19, 20. 1879.
. Sur la nature du charbon. Compt. rend. soc. de biol.,
1877, 6.s., IV. 317-320.
. Sur la resistance vitale des corpuscules reproducteurs du
vibrion de la septicemie. Compt. rend. soc. de biol., 1878, Par.,
1880, 6. s., V. 250.
. Conservation dans Palcool de 1'action virulente de sang
charge de corpuscules reproducteurs des vibrioniens charbonneux.
Compt. rend. soc. de biol., 1878, Par., 1880, 6. s., V. 133.
BERZELIUS. — Traite de Chimie, VI. 1829.
BILLROTH. — Untersuchungen iiber die Vegetationsformen von
Coccobacteria septica (Berlin, 1874 and 1879) ; Ueber Wund-
fieber und accidentelle Wundkrankheiten (Berlin, 1862); Sep-
topyohaemie (Chir. Klin. Wien, Berlin, 1879, 54 to 58).
BiRCH-HiRSCHFELD. — Researches upon Pyaemia. Archiv der
Heilkunde. 1873.
. Die Bacterien im Blut Pyamischer. Centralbl. f. d. raed.
Wissench. XL 609-612. 1873.
. Bakterien in syphilitischen Neubildungen. Centralblatt,
No. 33 (Aug. 19, 1882) and No. 44 (Xov. 4, 1882).
BOCHEFOXTAIXE. — Note sur quelques experiences relatives k 1'ac-
tion de la quinine sur les vibrioniens et sur les mouvements ame-
boides. Arch, de physiol. norm, et path., Par., V. 389, 724.
1873.
BOEHLEXDORF. — Ein Beitrag zur Biologie einiger Schizomyceten.
Dorpat, 1880, 8°.
BOLLIXGER. — Ueber die Bedeutung der Milzbrandbakterien.
Deutsche Ztschr. f. Thiermed., II. 341-350. 1875.
BORY DE SAIXT-VIXCEXT. — Diet, classique d'hist. nat. 1830.
BOULEY. — Communication sur la Septicemie. Bull. Acad. de med.,
Janvier, 1873.
. Inoculations preventives du charbon. Bull. Acad. de
med., Par., 1880, 2. s., IX. 942-955.
. Experiences publiques sur la vaccination du charbon
symptomatique, faites h Chaumont (Haute-Marne), le 26 septera-
bre, 1881. Compt. rend. Acad. d. sc., Par., 1881, XCI1I. 531-
537.
. De la vaccination contre le charbon symptomatique ; ob-
servations k la suite de la communication de M. Pasteur. Compt.
rend. Acad. d. sc., Par., 1881, XCIL 1383-1387.
. L'observation et experimentation : caracteres differentiels
de la fievre charbonneuse et du charbon symptomatique ; morve ;
460 BIBLIOGRAPHY.
syphilis; maladies de sang de la Beauve; inoculation preventive
de la peripneumonie contagieuse des betes a cornes. Bull. Acad.
de med., Par., 1881. 2. s., X. 1426-1447.
BOULEY. La peripneumonie contagieuse; solution experimentale
de la valeur de 1'inoculation comme mesure prophylactique.
Rec. de med. vet., Par., 1881. 6. s., VIII. 1031-1045.
. Inoculation preventive de la peripneumonie contagiense
des betes bovines. Bull. Acad. de me'd., Par., 1881. 2. s., X.
1080-1100, 1190-1212.
— . Sur, Tinoculation preventive de la peripneumonie conta-
gieuse des betes a cornes. Rec. de med. vet., Par., 1882. 0.
s., IX. 161, 222.
BRAIDWOOD (PETER MURRAY) and VACHER (FRANCIS). — Reports
to the Scientific Grants Committee of British Medical Associa-
tion. Third contribution to the life history of contagium. Lond.,
1882. 27 pp., 4 pi., 4°. Also British Med. Journal, January 14,
lss2.
BRANTLECHT. — Algues d'eau douce, leur role pathogenique. Ann.
d'Hyg. Public 3. s., II. 275. 1*7!).
. Pathogene Bacteriaceen ini Trinkwasser bei Epidemien
von Typhus abdomiualis. Arch. f. path. Anat., etc., Berl.,
1881. LXXXIV. 80-86
BRAURLL. — Sur le sang de rate. Virchow's- Archiv, XI. 132, et
XIV. 432. 1857.
BREFELD. — Studies on the Schizomycetes. Journal de Micro-
graphie. Vol. II. No. 9. 1879.
— . Unters. aus dem Gesammtgebiet der Mykologie. Heft 4.
Bot. Unters. iiber Schimmelpilze. 191 pp. (10 pis.). Leipzig,
1881.
BRUNET. — Sur la tuberculose experimental. Compt. rend. Acad. d.
sc., XCIII. 417.
BRUYLANTS et VERRIEST. — Recherches sur le microbe de la pleu-
ropneumonie bovine. Bull. Acad. roy. de med. de Belg., Brux.,
1880. :'.. s., XI\'. 540-558, 2 pi.
BUCHOLTZ. — Antiseptica and Bakterien. Arch. f. exper. Path. u.
Phannakol., IV. 1-81. 1875.
. Ueber das Verhalten von Bakterien zu einigen Antisep-
ticis. 8°. Dorpat, 187(1.
— . Ein Beitrag zur Kentniss der Ernahrungsverhiiltnisse von
Bakterien. Arch. f. exper. Path., etc. Leipz., VII. 81-100.
1877.
. Untersuchungen iiber den Einfluss der Temperatur anf
liakterien vegetation. Arch. f. exper. Path., etc., Li'ip/., I \'. 10!)-
Ki7. 1*77.
BUCHIOLITSA. — .Kwoprosil o pitanii bakterii. Voyennomed. J.,
St. Petersb. CXXIX. pt . 2. 2i.7-2.Ss. 1877.
BUCFIM i:. II. -On tin- Kxji<-riin<Mital Production of C.'ittle-dis-
t"iiij>"r Contagion t'roin the Hay Fungi. Sitz. d. k. -buyer. Akad.
d. \\ 18-418. 1878.
— . Experiments on the Origin of the Cattle-distemper by
Inspiration. Sitz. d. k.-bayer. Akad. d. NVi^s.. L880, 11 1-423.
di«: exeHmentelle Kr/cuguiii,' d«-s
BIBLIOGRAPHY. 461
tagiuins aus den Heupilzen nebst Yersuchen iiber das Ent-
stehen des Milzbraudes durch Einathmung. Miinchen, 1880.
F. Straub. 56 pp. 8°.
BUCHNER, II. Ueber die Wirkungen der Spaltpilze ira lebenden
Korper. Aerztl. Int.-Bl., Miinchen, 1880. XXVII. 128; 135-137;
110-149.
. Experimental Production of the Bacteria of Distemper.
Sitz. d. k. -buyer. Akad. Wiss., Miinchen, 1882, 147-169.
. Die Umwandlung der Milzbrandbakterien in unschad-
liche Bakterien und die Entgegnung R. Koch's an Pasteur.
Arch. f. path. Anat., etc., Bed., 1883, XCI. 410-422.
Ueber die experimentelle Erzeugung des Milzbrandcon-
tagiums aus den Heupilzen. In von Xageli Untersuch. u. nie-
dere Pilze. 8°. Miinchen, 1882.
BruriER. — Der Keuchhustenpilz. Berlin. Klin. Wchnschr., 1883.
XX. 7-9.
. Bacillus of Whooping-cough. Berliner Klin. Wochen-
schrift. Abst. in Brit. Med. Journ. January 27, 1883.
Bun RILL, T. J. Bacteria as a cause of disease in plants. Am.
Naturalist. Phila., 1881. XV. 527-531.
BUTLIN. — On the Nature of the Fur on the Tongue (4 plates).
Proc. Roy. Soc. XXVIII. 484-489. 1879.
CAGNIARD DE LATOUR. — Ann. de Chim. et de Phys. 2e serie,
LXXVIII. Memoires de 1'Institut, 23 novembre, 1836.
CAPITAX ET CHARRIX. — Sur la culture du Microbe du pus bleu.
Compt. rend. soc. de biol., Par., 1882. 7. s., III. 801.
CARMOXA DEL VALLE. — The yellow-fever fungus. Medical News.
Phila., July 21, 1883, 68, from Revista di Medicina y Cirurgia.
February and March, 1882.
CARTER, H. V. — Contributions to the experimental pathology of
spirillum fever ; its communicability by inoculation to the mon-
key. Med. Chir. Tr. London, 1880, 2. s., XLV. 7-148, 8 diag.
. Aspects of the blood-spirillum in relapsing fever. Tr.
Internat. M. Cong., 7. sess. Lond., 1881. I. 334-341.
CATTANBO, G. — Production of Microphytes within the Egg. Atti
Soc. Ital. Sci. Nat., XX. (1 pi.).
CAVAFY. — On the Effect produced on the Capillary Circulation
by the Injection of Putrid Blood into the Lymphatic Svstem.
St. George's Hospt. Rep. 1872-1875, VII. 17. "
. Injection of Putrid Fluids into Amphibia (St. George's
Hospital Reports, 1875).
CERI. — L'action de la quinin en rapport avec le de'veloppement
des germes et des organismes inferieurs, etc. Tr. Internat. M.
Cong. Lon.l., 1881, I. 466-472.
— . Bacillus Malarias. Arch, fiir Exp. Path., Vols. XV. and
XVI. 1882.
CIIAMBERLAXD. — Resistance des germes de certaines organismes a
la temperature de 100 degres. Compt. rend. Acad. d. sc.,
LXXXVIII. 659.
CIIAMIJERLAXD et Roux. — Sur 1'attenuation de la virulence de la
bacteridie charbonneuse, sous 1'influence d,es substances antisep-
tiques. Compt. rend. Acad. d. sc., Par., 1883, XCVI. 1088-
1091.
462 BIBLIOGRAPHY.
CHAPPIUS, E. — Action of Ozone on Germs contained iii the Air.
Bull. Soc. Chim., XXXV. 390.
CHAUVEAU. — Phenomenes de mortification sur 1'animal vivant.
Compt. rend. Acad. d. sc., 1873.
. De 1'agent pyohemique. Ass. fran9- Congres de Nantes,
1875.
. fitudes sur le sang de rate en Algerie. J. de med. vet.
et zootech., Lyon, 1880, 3. s., V. 449; 505.
. Etude experimentale de 1'action exercee sur 1'agent in-
fectueux par 1'organisme des moutons plus on moins refractaires
an sang du rate; ce qu'il advient des microbes specifiques intro-
duits directement dans le torrent circulatoire par transfusions
massives de sang charbonneux. Compt. rend. Acad. d. sc., Par..
1880, XCI. 680-684.
. Sur la resistance des animaux de 1'espece bovine au sang
de rate et sur la preservations de ces animaux par les inocula-
tions preventives. Compt. rend. Acad. d. sc., Par., 1880, XCI.
648-652.
. Nouvelles experiences sur la resistance des moutons alge-
riens au sang de rate. Compt. rend. Acad. d. sc., Par., 1880,
XC. 1396-1400.
. Des causes qui pen vent faire varier les resultats de 1'in-
oculation charbonneuse sur les moutons algcriens; influence de
la quantite des agents infectants; applications a la thcorie de
1'immunite. Compt. rend. Acad. d. sc., Par., 1880, XC. 1526-
1530.
. Nature de 1'immunitd des moutons algeriens contre le
sang de rate; est-ce une aptitude de race? Ibid., XCI. 33-36.
. De 1'attenuation des effets des inoculations virulentes par
1'emploi de tres petites quantites de virus. Compt. rend. Acad.
d. sc., Par., 1881, XCII. 844-848.
. Etude des ferments et des virus. Gaz. d. hop., Par.,
1881, LIV. 353; 361.
. fitude experimentale des conditions qui permettent de
rendre usuel 1'emploi de la methode de M. Toussaint pour attnmer
le virus charbonneux et vacciner les especes anirnales sujettes au
sang de rate. Compt. rend. Acad. d. sc., Par., 1882, XCIV.
1694-1698.
. De 1'attdnuation directe et rapide des cultures virulentes
par 1'action de la chaleur. Compt. rend. Acad. d. sc., 1883,
XCVI. 553-557.
— . De la faculte prolifique des agents virulents attcnues par
la chaleur, etc. Ibid. , 612-0 17.
. Du role de 1'oxygene de 1'air dans 1'attenuation, etc.
Ibid., 678-682.
CHAVANNES (de Lausanne). — Les principales maladies des vers
a soie. Geneve, Cherbulier, 1866.
( MI VNK. — Antiseptic Surgery. 8°, Lond., 1882.
. Report to the Association for the advancement of medicine
by research on the relation of micro-organisms to tuberculosis.
Practitioner, Lond.H188:J, XXX. 241-320, 1 pi.
CHIENE and EWART. — Do Bacteria or their Germs exist in the
BIBLIOGRAPHY. 463
Organs of Healthy Living Animals? J. Anat. and Physiol.,
Loud., XII. -Ii8-4o3, 1878.
CHIRONE, V. — Di un nuovo criterio per determinare con rigore
scientific© il valore relativo dei diversi antisettici ; ricerche speri-
mentali. Bull. d. sc. med. di Bologna, 1880, 6 s , VI. 5-24.
CIENKOWSKI. — Zur morphologie der Bakterien. Mem. Imp. Acad.
of Sci., St. Petersburg, 1878.
. Bacteria as the Cause of the Ropy Change of Beetroot
Suo-ar. (Abstr. by Prof. Lankester.) Quar. Jour. Micr. Sci.,
XIX. No. 73, 1879.
CLAXTOX. — Virulence of normal human saliva. Medical Times,
Phila., June 17, 1882, 627-631.
CLE"MEXTI. — Exp. Researches upon the Presence of Bacteria in
the Blood of Septicaemic Rabbits. Centralblatt. 1873.
COCHEZ. — Recherche du bacille de la tuberculose dans les crachats
des phthisiques. C. R. Soc. de biol., No. 19, May 26, 1883,
p. 362.
COHN. — Ueber die Entwicklung. mikroscop. Algen u. Pilze Nova
acta Acad. nat. cur., XXIV. 1853.
. Untersuch. iiber Bakterien. Beitrage zur Biologic der
Pflanzen, Bd. I. Heft 2, 127, 1872.
. Untersuch. iiber Bakterien. Ibid., Bd. I. Heft 3, 141, 1875.
Unters. iiber Bakterien. Ibid., Bd. II. Heft 2, p. 249,
1876.
. Zur weiteren Kenntniss des Febr. recurrens und der
Spirochaeten. Deutsche med. Wchnschr., Berl., 1879, V. 189.
COHN und MENDELSOHN. — Ueber Einwirkung des electrischen
Stromes auf die Vermehrung von Bakterien. Beitrage zur
Biologic der Pflanzen., Bd. III. Heft 1, 141, 1879.
COHXHEIM, J. — On the infectious causes of inflammation; two
lectures. Abst. in Med. News, Phila., 1882, XL. 62-64.
COLIN. — Mem. sur la fermentation vineuse. Ann. de Chim. et
Phys., 2e serie, XXVIII. 1825.
. Nouvelles recherches sur Faction des maladies putrides et
sur la septice'mie. Bull, de 1'Acad. de Med., 1873.
. Sur le developpement successif de foyers virulents pendant
la periode d'iucubation des maladies charbonneuses. Bull, de
1'Acad. de Med. 2e serie, VH. 199, 1878.
. Nouvelles recherches sur le role des ganglions lympha-
tiques dans la genese du charbon. Bull, de 1'Acad. de Med. 2. s.,
1879, VIII. p. 843, 1024.
Sur la Septicemie. Bull, de 1'Acad. de Med. Par., VII.
(1878), 1139-58, 1255-78; VIII. (1879) 9-31.
. Etiologie du Charbon. Rec. de Med. vet. 1880, 6. s., VII.
72, 177. Analyse experimentale.
. Analyse experimentale de la pustule maligne, etc. Bull.
Acad. de med. 1880, 2. s., IX. 650-677.
. Nouvelles experiences sur la culture des bacteridies char-
bonneuses dans le sol. Bull. Acad. de med., Par., 1881, 2. s.,
X. 103-128.
Quelques experiences sur la rage, la septicemie et le
charbon. Bull. Acad. de med., Par., 1881, 2. s., X. 694-703.
464 BIBLIOGRAPHY.
COLIX. De 1'evolution des organismes microscopiques sur Tanimal
vivant, dans le cadavre et les produits morbides. Presse vet.,
Par., 1SS:>, ill. 5-8.
YON COLLMANN. — Bakterien im Organismus eines an einer grossen
Verletzung am Oberschenkel verstorbenen zwanzigjahrigen Miid-
chens. 8°. Gottingen, 1873.
CORNEVIX, C. — Documents relatifs a la diphtheric des volailles.
J. de mod. vet. et de zootech., Lyon, 1879, XXX. 104-100.
COZE et FELTZ. — Recherch. exper. sur la presence des ini'us. dans
les maladies infect. Paris et Strasbourg, iNiii.
— . Researches clinical and experimental upon infectious
maladies. 8°. Paris, 1872.
CRIVKLLI and MAGGI. — Morfologia : Sulla Produzione del Bac-
terium termo, Duj., e del Vibrio bacillus, Duj. R. 1st. Lonib. di
sc. e lett. Rendic., Milano, I. 288-303, 399-406; 1809, II. 1208-
1212, 1868.
DE LA CROIX, N. Jalan. — Das Verhalten der Bakterien des Fleisch-
wassers gegen einige Antiseptica. Arch. f. exper. Path. u. Plmr-
makol., Leipz., 1880-1, XIII. 175-225.
CROOKE. — Bacteria in Pysemic Blood. Guy's Hosp. Gaz., Lond.
III. 77, 1878.
CROWTIIER, W. H. — Some experiments on the relative value of
antiseptics. Med. Times and Gaz., Lond., 1S79, II. 2<>1.
CUNNINGHAM. — Microscopic Examination of the Air of Calcutta.
Rep. to San. Com. with Govt. of India, 1872 (1874).
— . On the development of certain microscopic organisms oc-
curring in the intestinal canal. Rep. San. Com. India, 1878,
Calcutta, 1880, XV. 117-150, 1 pi.
CUBONI, G , und E. MARCHIAFAVA. — Neue Studien iiber die Na-
ture der Malaria. Arch. f. exper. Path. u. Pharmakol., Leipz.,
1880-81, XIII. 265-280, 1 pi.
DAHLKK, J. P. — On the Chemical Cause of the Transformation of
Starch into Sugar, Sugar into Alcohol, and Alcohol into Acetic
and Carbonic Acids, under the Influence of Inferior Organisms.
Arch. f. Anat. und Phys. f. Pfliiger. 1*75.
DALUHOBR. — Researches into the Origin and Development of
Minute and Lowly Life-forms, with a Glance at the Bearing of
th'-se upon tins Origin of Bacteria. 8°. London, 1*77.
- . On the Measurement of the Diameter of the Flagella of
Bacterium tenno. J. Roy. Mic. Soc., Lond., I. 109-175, 2 pi.
1878.
— . Recent Researches into the Origin and Development of
Minute and Lowly Forms of Life. Proc. of Roy. lust. G. B.,
Vol. VIII. Part 4, No, 07. 1879.
• - . Series of Experiments to determine the Thermal Death-
point of known Monad (icrms, etc. Journ. 11. Micr. Soc., III.
1-10. 1
DAVAINE. — Traitd des entozoaires. Paris%, IS.'D.
Recherches sur les maladies charbonneuMfl Compi. rend.
Acad. d. BO., LVII. 22.i. :;51. 886, <•( LIX. 898.
. Recherches sur les Vibrioniens. Conn it. rend. Acad. d. sc.,
LIX. 1864.
BIBLIOGRAPHY. 465
PAVAIXE. — Rech. sur la nature et la const, an at. de la pustule
maligne. Cornpt. rend. Acad. d. sc., LX. 1296. 1865.
. Sur hi presence constante des Bacteridies dans les ani-
maux infectes de maladies charbonneuses. Co nipt. rend. Acad.
d. sc., LXl. 334. 1666.
. Recherche sur une maladie septique de la vache, regardee
comme de nature charbonneuse. Compt. rend. Acad. d. sc., LXL
368. 1866.
. Art, Bacterie, Diet, encyclopedique des Sc. med., 1868.
. .Action de la chaleur sur le virus charbonneux. Compt.
rend. Acad d. sc., Sept., 187-'».
Action des substances antiseptiques sur le virus charbon-
neux. Compt. rend. Ac'ad. d. sc., Oct., 1873.
. Action des substances antiseptiques sur le virus de la
septicemie. Soc. de Biologie, 1*74.
. Observations relatives aux experiences de M. Paul Bert,
sur la maladie charbonneuse. Rec. de med. voter. 1877.
. Recherches etc. de la septicemie. Bull, de I'Acad. de
Med. 2« serie, V11I. 121, 1879.
et RAIMBERT. — Sur la presence des Bacteridies dans la
pustule maligne chez 1'hoinme. Compt. rend. Acad. d. sc., LIX.
1864.
DEM AIIQUAY. — Recherches experi men tales sur Pinfluence de cer-
taines substances sur le developpement des Vibrions. Union
Medicale, 1875.
DEPARTMENT OF AGRICULTURE. — Special Report No. 12. In-
vestigation of diseases of swine, and infectious and contagious
diseases incident to other classes of domesticated animals. \Ya.-h-
ington, 1879 : Govt. Printing Office, 292 pp., 18 pi. 8°.
DETMERS, H. J. — A pathogenic schizophyte of the hog. Am.
Naturalist. Pliila., 1882, XVI. 181-187; 105-203.
. Investigation of swine-plague. Third Report to Com-
missioner of Agriculture. Dept. of Agricult. Report, 1880, 527-
569, 14 pi.
DIEULAFOY et KRISHABER. — De Pinoculation du tubercle sur le
singe. Memoire couronne par 1'Institut. Arch, de physiol.
norm, et path. Par., 1883, 3. s., I. 424-435.
DOL^UIS, A. — Recherches experimentales sur la rage. Gaz. med.
de Par., 1881. 6. s., III. 114-116.
. De Pinoculation du virus rabique de Fhomme aux ani-
mnux; examen critique des experiences de Fhopital Trousseau
(Ste-Eu^enie) et recherches nouvelles sur ce sujet. Tribune
med.. Par., 1881. XIV. 63-66.
DOMFXU/O. M. — Bacillus of Contagious Molluscum. Atti Accad.
Lincei, Transunti, V. (1880) 77-79.
DO.XNK. -Animalcules observes sur les matieres purulentes et le
produit des secretions des organes genitaux de Phomme et de ia
femme. Compt. rend. Acad. d. sc., III. 385. 1836.
. Recherches sur la nature des mucus et des divers ecoule-
ments produits par les organes genito-urinaires de Phomme et de
la femrne. Coinpt. rend. Acad. d. sc., IV. 464. 1837.
30
466 BIBLIOGRAPHY.
DONN£. — Sur la generation spontanee des animalcules inf usoires.
Compt. rend. Acad. d. sc., LXIII. 1072. 18»><5.
. De la generation spontanee des moisissuros vegetales et
des animalcules infusoires. Compt. rend. Acad. d. sc., LXIII.
301. 1866.
. Experience relative aux generations des animalcules in-
fusoires, LXIV. 1867.
DOSE, A. P. J — Zur Kenntniss der Gesundheitsverhaltnisse d.
Marschlandes, Wechselfieber. Leipzig, 1878.
DOUGALL. — Powers of various substances in preventing the ap-
pearance of animalcules in organic fluids. Med. Times & Gaz.
Lend., April 27, 1872, 495.
. Disinfection by acids. Brit. Med. Journ., Kov. 8, 1879,
726.
DOWDSDELL. — On Atmospheric Bacteria. Quar. Journ. of Mic.
Sci., Jan., 1878.
— . The micro-organisms which occur in septicaemia. Quar.
Journ. of Mic. Sc., Lond., 1882, n. s., XXII. 06-75, 1 pi.
DRYSDALE. — -On the Existence of Flagella in Bacterium termo.
Monthly Mic. Journ. 1875.
. The germ theories of infectious diseases. Lond., 1878,
Bailliere (72 pp.) 8°, 1. s.
DUJARDIX. — Hist. nat. des Zoophytes infusoires. Paris. 1841.
DUMAS et BOULLAY. — Ann. de Chim. et Phys., XXXVII. 1828.
DUPEYRAT, DANIEL. — Recherches cliniques et experimentales sur
la pathogenic de 1'erysipele. Par., 1881, 85 pp. 4°.
DUVAL. — Mem. sur la inutabilite des germes microscopiques et la
?uestion des ferments. Journ. d'An. et Phys. de Ch. llobin,
X. 1873.
DUVITSKII. — Tablitsa, pokazvaioutchaja Kakie predmeti, Kakim
obrazom i Kakimi sredstvamisliednet dezinfectirovat. [Table
of disinfectants; their comparative value.] Vilna, 1879. 8°.
EBERTH. — Zur Kentniss der bakteritschen Mykosen. 4°. Leip-
zig. 1872.
. The Diphtheritic Processes. Centralblatt. 1873.
. Mycosis of Wounds in Frogs, and its Consequences. Cen-
tralblatt. 1873.
. The Bacteria of Perspiration. Arch. f. path. Anat. u.
phys., LXII. 1874.
. Untersuchungen iiber Bakterien. Arch. f. path. Anat.,
etc., LXII. 501-515, 1 pi. 1875.
— . On a New Pathogenic Bacillus. Arch. path. Anat. et
Phys., LXXVII. 29-34. 1879.
. Ueber einen neuen pathogenen Bacillus. Arch. f. path.
Anat., etc., fieri., 1879, LXXVII. 29-31. 1 j.l.
. Der Bacillus des Abdominal typhus. Virchow's Archiv,
Bd. 81 undBd. 83. 181
. Zur Kenntniss der Mycosen bei Thieren. Arch. f. path.
Anut, etc., fieri., 1880, LXXX. 311-314, 1 pi.
. Nene Unterouchungeii iibcr den Bacillus dps Abdominal
typhus. Arch. f. path. Anat., etc., fieri., 1881, LXXXIII. 480-
501, 1 pi.
BIBLIOGRAPHY. 467
EHRENBERG. — Infusoriens Thiere. 1838.
. Abhand. Akad. der Wissensch. zu Berlin. 1829-*1861.
EIDAM. — L'nters. liber Bakterien. Die Einwirkung verschiedener
Teinperaturen und des Eintrockenens auf die Entwicklung von
Bakteriuin tenno. Beit. z. Biol. d. Pflauzen, Bd. I. Heft 3, 208.
1875.
EKLTXD. — Note sur les microbes de la blennorrhagie. Nederl.
mil. geneesk. Arch., Utrecht, 1882, VI. 713-724.
EXGEL. — On the Production of Conidia by a Bacillus. Compt.
rend. Acad. d. sc., LXXXVlII. 976, 977. 1879.
EXGELMAXX, F. W. — Zur Biologic der Schizomyceten. Arch. f.
d. ges. Physiol., Bonn, 1881, XXVI. 537-545.
. New Bacterium sensitive to Light. Abstr. J. R. M. S.,
October, 1882, 356-657.
EVEUETT. J. T. — Investigations in relation to the cause and char-
acter of the diphtheritic poison, with numerous inoculations.
Med. & Surg. Reporter, Phila., 1881, XLV. 22M-232.
EWART. — On the Life-History of Bacterium Germs and Micro-
coccus (Proceedings of the Royal Society, Vol. XXVII. Xo. 118,
475) ; and of Bacillus Anthracis (Quarterly Journal of Micro-
scopical Society, 1878, 164).
. Disease produced by Bacilli. Brit. Med. Jo urn., Nov. 4,
1882, p. 884.
FABROXI. — Mem. sur les ferment, vineuse, putride, aceteuse. In
Ann. de Chimie, XXXI. 1799.
FKIILEISEX. — Die Aetiologie des Erysipelas. Bed., 1883, 38 pp. 8°.
. Ueber neue Methoden der Untersuchung und Cultur path-
ogener Bakterien. Sitzungsb. d. phvsmed. Gesellsch. zu Wiirtzb.,
1882, 113-121.
FELTZ, V. — Note sur la septice'mie experimentale. Compt. rend.
Acad. d. sc., 30 nov., 1875.
. Rech. experiment, sur le principe toxique du sang putrefie.
Compt. rend. Acad. d. sc. 1875.
Experiences demontrant que la septicite du sang putrefie
ne tient pas a un ferment soluble. Compt. rend. Acad. d. sc.,
1877, LXXXIV. 789.
. Recherches experimentales sur un leptothrix trouve pen-
dant la vie dans le sang d'une femme atteinte de fievre puerperale
grave. Note, presentee par Ch. Robin. Compt. rend. Acad. d.
sc., Par., 1879, LXXXVlII. 610-612.
. Considerations sur les conditions de developpement du
leptothrix d'origine puerperale. Mem. Soc. de med. de Nancy
(1878-9) 1880, 48-50.
FESER. — Beobachtungen und Untersuchungen iiber den Milz-
brand. Deutsche Ztschr. f. Thierined., Leipz., 1880, VI. 166-
213.
FIESSIXGER. — Note sur les organismes qui peuvent se developper
dans les solutions pheniquees. Rev. med. de Pest, Nancy, 1882,
XIV. 202-207.
FIRKET, C. — Note sur la recherche des micrococcus dans Pinterieur
des oi-ganes. Ann. Soc. med.-chir. de Liege, 1879, XVIII.
2 18-255.
468 BIBLIOGRArHY.
FITZ, A. — Fermentation by Schizomycetes. Berl. deutsch. Chem
Ges., XIII. (18SO) 1309-1312.
FORBES, S. A. — Bacterial Parasite of the Chinch Bug. Amer.
Natural., XVI. (1882) 824-825. Abstr. J. Roy. M. S., Deer
1882, 830, 831.
FREIRE. — Yellow-fever fungus. Journal Officiel de 1'Empiie de
Bresil, May 8, 1883.
FRIEDRICH. — Pathogenic Bacteria in Salt-water Marshes. Mcd.
Rec. N. Y. XVI, 547, 1879.
FRIEDLANDER, C. — Ueber die Schizomyceten bei der acuten
fibrosen Fneumonie. Arch. f. path. Anat., etc., Berl., 1882,
LXXXVII. 319-324, 1 pi.
FRISCH. — Ueber den Einfluss niederer Temperaturen auf die
Lebensfahigkeit der Bakterien. Sitzungsb. d. k. Akad. d. \Viss-
ensch., Wien, LXXV. 257-269. 1877.
. Verfahren zur Untersuchung zum Conserviren und Plioto-
graphiren der Bakterien. Ztschr. f. Mikr., I. 119-122. 1878.
. Ueber das Verhalten der Milzbrandbacillen gegen extrem
niedere Temperaturen. Sitzungsb. d. k. Akad. d. Wissensch.,
1879, LXXX.
VON FROSCHAUER. — Demonstration iiber das Verhalten der Schim-
mel-vegetation und der septischen Infektion zurn Schvvefelwasser-
stoff, mit beziiglichen Mittheilungen. Wien. ined. Presse, 1882,
XXTII. 305-367.
GALTIER. — Inoculation de la morve au lapin ; destruction de
1'activite virulente morveuse par la dessiccation ; transmission
de la morve par 1'inoculation de la salive [avec observations de
M. Larrey.] Compt. rend. Acad. d. sc., Par., 1880, XCI. 17.1.
. Les injections de virus rabique dans le torrent circulatoire
ne provoquent pas 1'eclosion de la rage et semblent conferer J'iiu-
munite; la rage peut etre transmise par 1'ingestion de la matiere
rabique. Compt. rend. Acad. d. sc., Par., 1881, XCIII. 2*1.
GAMGKK. — Exp. sur 1'inject. du pus dans les vaisseaux sanguins.
In Gaz. med. de Lyon. 1855.
GARDNER, J. — Milk-sickness; its microscopy. St. Louis M. and
S. J., 1880, XXXVIII. 288-294. Also, Indiana M. Reporter,
Evansville, 1880, I. 145-151.
GASPARD. — Memoire phys. sur les maladies purulentes et putrides.
In Journ. de Magendie, 1822.
GAUCHER, E., et HILLAIRET. — Parasitisme de la lepre. Progres
meU, Par., 1880, VIII. lo:J!».
GAUTIER. — Sur une maladie nori encore ddcrite des vins du midi
de la France, dit vins tournes. Compt. n-nd. Acad. d. sc. 1*7 •>.
GAYON, U. — Alteration 8|»ontanee des oeufs. These Fac. des. Sc.,
Par., No. 362. 1S75.
GAY-LrssAC. — Memoire sur la ferment. In Ann. de ('him.,
L\X\ I. 1810.
<.i i:r.i:i: und Bn:rn-IIn:sriiFF,Ln. — Ueber einen Fall von Endo-
carditis ulcerosa und d.i> \ dikommen von Bakterien in du-srr
Knu.kheit. Arch, der H-ilk. XVII. 208, 1877.
GESSAHD. — Sur les colorations bleue et vertc d<-s linges a panse-
ments. Compt. rend. Acad. d. sc., XCIV.
BIBLIOGRAPHY. 469
GIBIER, P. — De 1' aptitude communiquee aux animaux & sangfroid
a contractor le charbon par 1'eievation de leur temperature. Compt.
rend. Acad. d. sc., Par.. 18*2, XCIV. 1005.
GIBBES, II. — An easy method of detecting bacillus tuberculosis
for diagnostic purposes. Lancet, Lond., 1882. II. 183.
G< I--KLIX et ROBIN. — Recherches sur 1'urine ammouiacale. Compt.
rend. Acad. d. BC., 1874.
GREENFIELD. — Bacillus anthracis. Rep. to Royal Agricultural
Society. Quar. Journ. Micr. Sc., No. LXXIX. 374, 1879.
. Report on an inquiry into the nature, causes, and pre-
vention of splenic fever, quarter-evil, and allied diseases, made at
the Brown Institution. J. Roy. Agric. Soc. Eng., Lond., 1880,
2. s., XVI. 273-311.
GRIFFIXI, L. — SulP azione tossica della saliva umana; studio
sperimeutale. Arch, per le sc. med., Torino, 1881. V. 247-258,
Ipl.
GROSSMAXX and MAYERIIAUSER — Upon the Life of Bacteria in
Gases. Arch, fur gesammte Phys. von Pfliiger, XV. 245. 1878.
GCBLER. — Fermentation ammoniacale de 1'urine. Conipt. rend.
Acad. d. sc. 1874.
GUE'RIN. — Etude sur P Intoxication Purulente, comprenant cinq
discours prononces a 1' Academic de Medicine, etc. Par., 1879.
. Cholera des Ponies ; vaccine et variola. Bull. Acad. de
med., Par., 1880, 2. s., IX. 1008-16.
Sur Tinoculation preventive de la peripneumonie conta-
gieuse. Bull. Acad. de med., Par., 1881, 2. s., X. 1219-1237.
Sur les inoculations virulentes preventives. Bull. Acad.
roy. de med. de Belg., Brux., 1882, 3. s.. XVI. 600-622.
GUTMAXX, W. — Esperimenteller Beitrag zur Lehre von der putri-
den Intoxication und Septicaemia. Dorpat, 1879. 8°.
HABERKORX, T. — Das Verhalten von Harnbacterien gegen einige
Autiseptica. Dorpat, 1879. 8°.
. Morphology and Genetic Relationship of Pathogenous
Bacteria. Bot. Centralbl., X. 1882. 100-6.
HAI.LIER. — Die Pflanzenlichen Parasiten. Leipzig, 1866.
HAMLET. W. M. — On the action of compounds inimical to bac-
terial life. J. Chem. Soc., Lond., 1881, XXXIX. 326-331.
HAXOT, V. — Miliaire bacteridienne dans la fievre typhoide. Rev.
de med., Par., 1881, I. 821-828.
UARZ. — A New Micrococcus Form in the Living Animal. (Sep.
imp. from Zeitshcr. f. Thiermed.) Leipzig, 1879.
HANSEN, E. C. — Contribution to the Knowledge of Organisms
which live in Beer and the Wort of Beer. 1. Researches on the
Organisms which at Different Periods of the Year are found in
the Air at Carlsberg and neighborhood, and which develop in
Beer-wort, I. 49-67. 2. On the membranes, 67-72. 3. Organ-
isms absorbed in Beer and Wort, 72-75. 1879.
HANSEX, G. A. — Bacillus leprae. Nord. med. Ark., Stockholm,
0, XII. 1-10, 1 pi.
— . The bacillus of leprosy. Quart. J. Micr. Sc., Lond.,
1880, n. s., XX. 92-102, 1 pi. Also, Arch. f. path. Anat., etc.,
fieri., 1880, 7 F., IX. 32-42, 1 pi.
470 BIBLIOGRAPHY.
HANSEN, G. A. — Studien iiber Bacillus leprae. Arch. f. path.
Anat., etc., Berl., 1882, XC. 542-548.
HASSALL, A. II. — On the Development and Signification of Vibrio
ureola, Bodo urinaris, and on certain Fungoid and other Pro-
ducts generated in Alkaline and Albuminous Urine. Lancet,
Lond., II. 10, 1854.
. Report on the Examination of certain Atmospheres dur-
ing the Epidemic of Cholera, by Dr. Thomson. Relation of
Cholera Epidemic of 1854, 119. 1855.
. Report on the Microscopical Examination of the Blood
and Excretions of Cholera Patients. Relation of Epidemic
Cholera of 1854. 1855.
HATTON, F. — Ou the action of bacteria on gases. J. Chem. Soc.,
Lond., 1880-1881, XXXIX. 247-258.
HAUPT. — Ueber das Tingeren und Prapariren der Bakterien.
Ztschr. f. Mikr. Berl. I. 175-179. 1878.
HAUSSMANN. — Ueber das primiire Vorkommen von Bakterien in
einem geschlossenen menschlichen Ei. Arch. f. path. Anat.,
etc., LXVII. 11. 1876.
HKIDENREICH, L. — Ueber die Schraubenbacterie des Riichfallsty-
phus. Petersb. med. Wochensch., 1876.
Jlr.scuL. — Ueber das Vorkommen von Mikrokokken bei einigen
Krankheiten. und ihren Xachweis durch Methylgriin. Wien.
med. Wchnschr., 1880, XXX. 705, 7-si), 81:3-810.
HILLER, ARNOLD. — Der Antheil des Bakteries am Faulnissprocess
im besondere der Harnfaulniss. Centralblatt, 1874.
— . The Inflammatory Process in Erysipelas. Berlin klin.
Wochensch., 1874.
— . Bacteria and Suppuration. Centralblatt f. Chirurgie, 1874.
. Ueber diagnostische Mittel und Methoden zur Erkennung
von Bakterien. Arch. f. path. Anat. und Phys. LXII. 1875.
— . Contribution to the Study of the Nature of Contagia and
of Putrefaction. Archiv f. klin. chir., 1875.
— . Ueber Extrahirbares Putrides und Septicamisches Gift.
Centralblatt fur Chirur., 1870, Nos. 14 and 15.
HOFFMANN. — Etudes mycologiques sur la fermentation. Ann.
des Sc. nat. bot. XIII. 1800.
. Mc'morie sur les Bacteries. Ann. des Sc. nat. bot. 5°
s., XI. 1869.
HORSLEY. — On " septic bacteria" and their physiological relations.
Rep. Med. Off. Local Gov. Bd., 1881, Lond., 1882, 239-280, 2 pi.
IIn;i:i:. K. — Experimentelle Studien iilx-r Mil/brand. Deutsche
med. Wchnschr., Berl., 1881, VII. 89 - !)5.
HUBER, C. — Septhiimif und Pyiimie. Pitha and Billroth's Chi-
rurgie, Band I. Abth. II. Heft I.
JACOBS. — Granulations et molecules punctiformes de la vaccine.
Press*' M..1., XXVII. 1875.
JOLY et MrssKT. — Kxp. sur 1'hcterogdnie. Compt. rend. Acad.
d. sc., LI. 627. IM;U.
Jni.vi.T. Sin- IVtioloMH- ct la pat li« >u«;n i«> d«' l;i v;iri«)l<' «lu ]>i'^'(>n,
]•• dr-vi'ldj'i'iMin-iit ili'> inicrcbrs intVclii.'iix dans l:i lymphe.
Compt. rend. Acad. d. sc., Par., Ibbl, XCII. L 522-1525.
BIBLIOGRAPHY. 471
KAPOSI. — Ueber den gegenwartigen Stand der Lehre von der
iitiologischen Beziehung kleinster Organismen (Micrococcus) zu
den Infektionskrankheiten. 8°, Wien, 1874.
KAI IMAXN. — Ueber die Zersetzung des Blutes durch Bacillus
subtilis. 8°, Leipzig, 1878.
KEATIXG, JOHN M. — The presence of the micrococcus in the
blood of malignant measles. Phil. Med. Times, Vol. XII. Xo.
7iJti-771.
K MIX. ii. — Contribution to the history of paludial maladies, etc.,
in Arch. gen. de medecine. 1880.
KERX, E. — Bacteria of Caucasian Milk Ferment. Bot. Ztg., XL.
(1882) 204-266.
KEYSKU. — Is gonorrhoea a bacterial disease? Maryland M. J.,
Baltimore, 1882-1883. IX. 481-488, 1 pi.
KixtiSKTT. — Contributions to the History of Putrefaction. Part
I. Journ. Chem. Soc., XXXVII. 1880." 15-22.
KLEBS. — Contribution to the Study of Micrococcus. Archiv f.
exper. Pathol., I. 1873.
. Beitriige zur Kenntniss der pathogenen Schistomyceten.
Arch. f. exper. Path. u. Pharrn. 1873, I. 31, 4 pi., 443"; 1875,
III. 305; IV. 107, 1 pi., 207, 2 pi., 409, 1 pi.; 1876, V. 350.
• . Das Contagium der Syphilis; eine experimentelle Stiulie.
Arch. f. exper. Path. u. Pharmakol. Leipzig, 1879. X. 161-
221. 2 j,}.
. Beitrage zur Kenntniss der Micrococcen (Archiv fiir Ex-
periment. Patholog. und Pharmak. 1873. Band I.).
. Der Micrococcus der Variola und Vaccine. Arch. f. ex-
per. Path. u. Phar. Leipzig, 1879. X. 222-227, 2 pi.
Der Bacillus des Abdominaltyphus und der typhose Pro-
cess. Archiv fiir experimentelle Pathologic. 1881. XIV.
KLEHS. E. und ToMMASi-CuuDELi. — Studien iiber die LTrsache
des Wechselfiebers und iiber die Natur der .Malaria. Arch. f.
exper. Path. u. Pharmakol. Leipzig, 1879. XI. 311-398, 3 pi.
2 tab.
. Einige Satze iiber die Ursachen der Wechselfieber und
die Xatnr der Malaria. Arch. f. exper. Path. u. Pharmakol.,
Leipz., 1879. XI. 122-130.
KLEIX. — On the Pathology of Sheep-pox. Quar. Journ. of Mic.
Sc. n. s. Xo. LIX. 229. 1875.
. Report on infectious pneumo-enteritis of the pig (so-
called pier-typhoid). (Preliminary note by E. C. Seaton.) Rep.
Med. Off. Local Gov. Bd., 1877. Lond., 1878. 169-280,
2<; pi.
• . Experimental contribution to the etiology of infectious
diseases, with special reference to the doctrine of contagium vi-
vum. Proc. Roy. Soc. Loud., 1878. XXVII. 101-107.
. On the relation of pathogenic to septic bacteria, as illus-
trator! by anthrax cultivations. Rep. Med. Off. Local Gov. Bd.,
1881. 166-206, 3 pi. Lond., 1882.
Morphological variety of Bacillus Anthracis. Quart. Jour.
Mic. Sci, n. B. No. XC. 260. April. 1883.
KOCH. — Die Aetiologie der Milzbraudkrankheit, begriindet auf
472 BIBLIOGRAPHY.
die Entwick. des Bacillus anthracis, Beitrage zur Biol. der Pflan-
zen, Bd. II. Heft 2, 277. 1876.
KOCH. — Verfahren zur Untersuchung zum conserviren und photo-
graphiren der Bacterien. Beitrage zur Biologic der Pflaiizen,
II. 398. 1878.
. Researches upon Charbon. Berlin Wochenschrift, Nos.
18 and 19. 1878.
. Untersuchungen liber Bacterien. Cohn's Beitrage zur
Biologic der Pflanzen, Bd. II. lift. 3, s. 399.
. Untersuchungen lib. die Aetiologie der Wundinfec-
tionskrankheiten. Leipz., 1878, F. C. W. Vogel. 83 pp.
5 pi. 8°.
Investigations into the etiologie of traumatic infective
diseases. Translated by W. Watson Cheyne. Loud., 1880, New
Sydenham Society, 87 pp., 5 pi. 8°.
. Zur Untersuchung von pathogenen Organismen. Mitth.
a. d. k. Gsndhrsamte, Barl., 1881. 1. 1-48, 1-1 pi.
. Ueber Disinfection. Mitth. a. d. k. Gsiidhtsamte, Berl.,
1881. I. 1-49.
. Zur Aetiologie dcs Milzbrandes. Mitth. a. d. k. Gsndhts-
amte, Berl., 1881. 1.1-31.
. Die Aetiologie der Tuberculose. Berl., Klin. Wchnschr.,
1882. XIX. 221-230.
. Ueber die Milzbrandimfung. Kassel und Berlin, 1883.
. Ueber die Aetiologie der Tuberculose. Verhandl. d. Cong.
f. innere Med., Wiesb., 1882. I. 56-79.
L'inoculatiori preventive du charbon. Replique au dis-
cours prononce & Geneve par M. Pasteur. Berlin, 1883, 8°
. Ueber die Milzbrandimpfung. Eine Entgegnung auf den
von Pasteur in Genfgehaltenen Vortrag. Kassel u. Berl., 1882.
37 pp. 8°.
KOHLER, FERDINAND. — Der Heupilz (Bacillus subtilis) in seinem
Verhalten nach rnehrfachen Umziicntangen in Fleischextract-
losungen und im Kaninchenblut, zum thierischen Organismus.
Gottingen, 1881, W. F. Kashner. 24 pp 8°.
KOLACZEK. — Bacterien im normalen Blute. Centralbl. f. Chir.,
II. 197. 1875.
KUI.IIX, P. — Ein Beitrag zur Biologie der Bacterien. Dorpat,
1879, 8°.
LALLIER. — Sur la fermentation ammoniacale de Purine. Compt.
rend. Acad. d. sc, 1874.
LANDAU. — Zur Aetiologie der Wundkrankheiten, etc., Verhandl.
d. deutsch. Gesellsch. f. Chir., II. 1M-220. 1874.
. Zur Aetiologie der Wmidkrankheitrn nrl>sf Yrvsiu'hen
iiber die Beziehungen der Faulniss-Bacterien zu desselben.
Archiv f. klin. Chir. XVII. 4 fasc. 527. 1875.
LASSAR, O. — Die Micrococcen der Phosphoresconz. Arch. f. d.
Ges. Physiol., Bonn, 1880. XXI. 104-109. 1880.
LAVERAN, A. — Naturu parasitaire des accidents de rimpaludisme;
description d'un nouveau ]>ar;isite tuouvc dans \<\ san^ dcs ma-
lades atteints de fifcvre palustre. Par., 1881. J. B. Bailliere et
fila. 104pp., 2 pi. 8°.
BIBLIOGRAPHY. 473
LAW, JAMES. — Investigation of swine-plague. Third Report to
Commissioner of Agriculture. Dept. of Agricul. Report, 1880,
455-526, 10 pi.
LEBLAXC. — Sur 1'inoculation preventive de la peripneuraonie con-
tao-ieuse des betes a comes. Bull. Acad. de med., Tar., 1681.
2. s., X. 1168-1182; 1301-1308.
LEBKDKFF, A. — Contribution a 1'etude de 1'action de la chaleur
et de la dessication sur la virulence des liquides septiques et sur
les organismes inferieurs. Arch, de physiol. norm, et path., Par.,
1882. 2. s., X. 175-2; 4.
LEEUWENHOEK. — Op. omnia, I.; Anat. et Contemp., 37, Lugd.
Batav. 1772.
LEMAIRE. — Recherches sur les microphytes, les microzoaires et les
fermentations. Compt. rend. Acad. d. sc., LVII. 625; LIX.
317-425. 1863.
LEMKE, C. — Uber das Verhalten des Bacillus anthracis zum Milz-
brand und liber das Eindringen desselbeu respective seiner Spo-
ren von den Lungenalneolen aus in die Blutbahn. Getting.,
1879. 8°.
LEPLAT et JAILLARD. — De 1'action des Baeteries sur Teconomie
animale. Compt. rend. Acad. d. sc., LIX. 250. 1864.
. Note sur la non-existence des Baeteries chez les lapins
morts a la suite d'inoculation du charbon avec les phen. du sang
de rate. Compt. rend. Acad. d. sc., LXI. 298. 1865.
Nouvelles exp. pour demontrer que les Baeteries ne sont
pas la cause du sang de rate. Compt. rend. Acad. d. sc., LXI.
436. 1865.
LKTZ ERICH. — Microscopic Reactions of the Fungus of Diphtheria.
Berlin klin. Wochensch. 1874.
. Diphtheria Local and General. Arch. f. path. Anat. u.
Phys., LXI. 1S74.
. Untersuchungen iiber die morphologischen uuterschiede
einiger pathibgenen Schistomvceten. Arch. f. exper. Path. u.
Pharm., Leipz., 1879-1880. "XII. 351-365.
. Experimentelle Untersuchungen iiber Typhus abdomi-
nalis. Arch. f. exper. Path. u. Pharmakol., Leipz., 1881. XIV.
212-227, 1 pi.
LEUBE, W. O. — Beitrage zur Frage vom Vorkommen der Bakte-
rien im lebenden Organismus, speciell im frisch gelassenen
Harn der Gesunden. Ztschr. f. klin Med., Berl., 1881. III.
233-240.
LEWIS. — The Microphytes which have been found in the Blood,
and their Relation to Disease. (1 plate and 18 woodcuts). Quart.
Jour, of Mic. Sci. XIX. 356-404. 1879.
. Flagellated organisms in the blood of healthy rats. Quart.
J. Micr. sc., Lond., 1879. n. s. XIX. 109-114.
LEX. — Ueber Fermentwirkungen der Bakterien. Centralbl. f. d.
med. Wissensch. X. 291, 305, 513. 1872.
LEY HEX. — Die Mikrokokken der Cerebro-spinal-Meningitis. Cen-
tralbl. f. klin. Med., Leipz., 1883. I\7. 101-105.
LINGARD and BATT. — On an infectious ulcerative disease of skin
474 BIBLIOGRAPHY.
and mucous membrane caused by a specific bacillus. Lancet,
Lond., 1883. I. 034.
Lit HTIIKIM. — Ueber pathogene Schimmelpilze. Berl. klin.
Wrlmsrhr., 1882. XIX. 129, 147.
LISTER. — A further Contribution to the Natural History of Bac-
teria and the Germ Theory of Fermentative Changes. Quart.
,]. Micr. sc., Lond., X1I1. 380-408, 3 pi. 1873.
. A Contribution to the Germ Theory of Putrefaction and
other Fermentative Changes, and to the Natural History of To-
rulaB and Bacteria. 4°. Edinburgh. 1875.
. The Lactic Fermentation and its Relations with Pathology.
Med. Times and Gaz., Dec. 22, 1877.
. The Nature of Fermentation. Quart. J. of Mic. Sc.,
XVIII. 177. 1878.
. On the relation of micro-organisms to disease. Quart. J.
Micr. Sc., Lond., 1881. n. s., XXI. 330-342.
LITTKX. — Beitriige zur Lehre von Abdominal typhus. Charito-
Annalen. 1881.
Livox. — Injections de bacteridies dans le sang, sans aucim phe-
nomene d'int<>xirati<>n. Compt. rend. Soc. de biol., LS77. Par.,
1879. 6. s., IV. 35:».
LoEWKXBi.iMr, B. — Recherches sur la presence de micrococcus
dans 1'oreille malade; considerations sur le role des microbes
dans le furoncle auriculaire et la furonculose gc>nerale; applioa-
tions therapeutiques. Compt. rend. Acad. d. sc., Par., 1880,
XCI. .V).">.
LOGAX, J. H. — The milk-sickness of Upper Georgia and of other
portions of the United States. Atlanta M. Reg., Ib81-1882, I.
158-469.
LJ'DKKS. — Ueber Abstammung und Entwickelung des Bacterium
Tenno, Duj. Arch. f. mikr. Anat., Bonn, 111. 817-844, 1M>7.
LI(,INI;I IIL. — The Micrococcus of Variola. Verhandl. d. physik.
med. Gesel. 1873.
LI-KOMSKI. - Researches upon Erysipelas. Arch. f. path, und
phys., LX. 1874.
MADDOX. — On some Micro-organisms from rainwater ice and
hail. Journ. Roy. Mic. Soc., ser. 11, vol. II. part 2, 449.
MA«;XIX. — L'-s Baettriefl. Paris. 1-878, 8°.
MARCAXO, V. — Fermentation of Maize-Starch. Compt. rend.
Acad d. sc., XCV. (1882) 345-47.
M \i:< IIAXD. — Bacillus Malarias. Arch. Virchow. Vol. LXXXVLEI.
104, April, 1882.
M.\i:riiiAi AVA, E. — Studi sulla malaria. Salute, Geneva, 1880,
2. s.. XIV. 225,
. Sopra il micrococco della gonorrea. (la/x d. osp., Milano,
1882, III. 10:5.
M I., i i \. M.— Prevention of Fermentation by Vegetable Acids.
X.-itM-hr. f. Spiritusindostrie, IV. (1881) 111.'
MAKTIX. — PtedK-rches sur la structure et le d^veloppement des
I', • : Vil.rioniens. Sm-. P.'n.l. l>7(i.
IfASSB. Dei inoculations Pn'v«-iitivu.s dans les Maladies Viru-
lentL-s. Pari-. pp., 1 pi.
BIBLIOGRAPHY. 47 5
MAYER. — Manual of the Chemistry of Fermentations. Heidel-
berg. 1874
ME<;XIX, P. — iStude sur une epizootic du typhus du pore (vulgaire-
ineut le rouge, le rouget, le violet). J. d. conn. med. prat., Par.,
1S7D, 3-s, I. 403, 409.
MEYER, H. — Ueber das Milchsaureferment und sein Verhalten
gegeu Antiseptica. Dorpat, 1880. 8°.
MKYER, WILH. — Untersuchungen liber den Bacillus des Abdomi-
naltyphus. Dissertation der Berliner med. Facultat. 1881.
MIFLET. — Researches on the Bacteria suspended in the Air.
Beitr. Biol. Pflanzen III. 119-140. 1880.
MIKULIEZ. — Ueber die Beziehungen des Glycerins zu Coccobac-
teria septica und zur septischen Infektion. Arch. f. kliu. Chir.
XXII. 253-327. 1878.
. Des bacteries atmospheriques. Compt. rend. Acad. d.
sc., Par., 1880, XCI. 64-67.
MIQUEL. — Recherches sur les Bacteries aeriennes faites h 1'obser-
vatoire Montsouris. Soc. frai^aise d'hygiene. 1877.
. Further Researches on the organized "Dusts" of the
Atmosphere, 10 figs. Annuaire de 1'Observ. de Montsouris, 1880,
386-513.
. Poussieres organisees de 1'atrnosphere. Ann. d'Hyg.
Public, 2e serie, II. 226, 333. 1880.
Mouisox. — Bacteria and their presence in syphilitic secretions.
Maryland Med. Journ., Vol. IX. Xo. 17. 385-388.
. Second Paper. Maryland Med. Journ , Bait., 1883, X.I.
Moss, E. L. — Experiments on Septic Organisms in Living Tis-
sues. Rep. Brit. Asso. Adv. Sci., 49th Meeting, 1879, 416-418.
1880.
Moxox and GOODHART. — Observations on the Presence of Bac-
teria in the Blood and Inflammatory Products of Septic Fever,
and on Cultivation of Septicaemia. Guy's Hospital Reports,
1875, XX. 229.
MrLLER, O. F. — Animalia infusoria fluv. et marina. 1786.
Mrxxz. — Recherches sur la fermentation intracellulaire des vege-
taux. Ann. de Chim. et de Phys. XIII. 543. 1878.
XAGELI. — Die niederen Pilze in ihren Beziehungen zu den Tnfek-
tionskrankheiten und der Gesundheitspflege. Munich. 1877.
— . Theory of Fermentation. Abh. Bay. Akad. Miinchen,
XIII. Part 2, 75-205. 1879.
. Experimental Production of the Bacteria of Cattle Dis-
temper. Sitz. Akad. Wiss. Miinchen, 1882, 147-169. Abstr. J.
R. M. S., June, 1882, 3s-j.
Vox NAGELI, C. und II. BUCHNER. — Der Uebergang von Spalt-
pilzen in die Luft. Centralbl. f. d. med. Wissensch., Berl., 1882,
XX. 513-515.
. Untersuch. iiber die niederen Pilze. Miinchen, 1882.
-EN, F. — Blue Milk. Conn's Beitr. Biol. Pflanzen, III.
J18SO) 187-246.
NEIDHARDT. — Mittheilungen iiber die Veranderungen der Zunge
in Krankheiten. Arch. d. Wissensch. Heilkunde. Bd. V. 1661,
s. 294.
476 BIBLIOGRAPHY.
NEISSER, A. — Die Mikrokokken der Gonorrhoea; referirende
Mittheilung. Deutsche med. Wchnsche., Bed., 1882, VIII.
379-282.
- . Weitere Beitrage zur Aetiologie der Lepra. Arch. f. path.
Anat., etc., Berl., 1881, LXXXIV. 514-542, 1 pi.
NENKI. — Relation of Oxygen to the Life of the Microzoa. Journ.
Prakt. Chem., XIX. 337-358. 1880.
- . Contributions to the Life-history of the Schizomycetes,
62 pp. 2 plates and 7 figs. (8vo, Leipsic, 1880.)
NK.NKI, M., und P. GIACOSA. — Giebt es Bakterien oder deren
Keiine in deii Organen gesunder lebender Thiere ? J. f . prakt.
Chem., Leipz., 1879, n. F., XX. 34-44.
NENCKI, M., und F. SCHAFFEK. — Ueber die chemische Zusam-
meusetzung der Faulnissbakterien. J. f. prakt. Chem., Leipz.,
1879, n. F., XX. 443-466, 1 pi.
NICATI. — Sur diverse epizootics de diphtheric des oiseaux de
basse-cour observees a Marseille, et sur les relations possible de
cette maladie avec le diptherie de 1'espece humaine. Compt.
rend. Acad. d. sc., LXXXVIII. 297.
NOTHNAGKL, H. — Vegetable Organisms in Human Excrements.
Zeitsch. fur Klin. Med., 1881, 1 pi.
- . Bacillus Amylobacter (Clostridium batyricum) in Dartn-
inhalt. Ceutralbl. f. d. med. Wissensch., Berl., 1871, XIX. 1!)
NORMAND. — Du role etiologique de 1'anguillule dans la diarrhc'e
de Cochinchine. Arch, de med. nav., LJar., 1878, XXX. 214-
224.
NOTTER, J. L. — Experiments on disinfectants. Army M. Dep.
Rep., 1878, Lond., 1880, XX. 217-222.
OEMLER, H. — Experimented Beitrage zur Milzbrandfrage. Arch.
f. wissensch. u. prakt. Thierh., Berl., 1878, IV. 261; 1879, V.
164 ; 1880, VI. .401-423.
OERTEL. — Zur Aetiologie der Infektionskrankheiten. 1881.
OGLE. — Fatal Epidemic (Typhoid) Disease among Fish, whose
Blood during Life contained Bacteria* Lancet, London, II. 657.
1873.
OGSTON, A. — Report upon micro-organisms in surgical diseases.
Brit. M. J., Lond., 1881, I. 3i;«.) -37.'), 1 pi.
OLLIVE, C. — Sur la resistance des moutons de la race barbarine
a Pinoculation du charbon. Compt. rend. Acad. d. sc., Tar.,
1*70, LXXXIX. 792.
OLIVIER. — Les microbes des poissons marins. Compt. rend. Arml.
d. sc., Par., 1883, XCVI. 384-386.
— . Les germes de 1'air. Rev. Scient., Par., 1883, XXXI.
290-297.
OMMUS. — Sur 1'infection putride. Bull. Ac. de mdd., 11 Mars,
1-7.;.
- . Sur la septicemie. Bull. Ac. de HUM!., 1 5 Avril ct 9 Sept.,
1873.
ORTII. — Researclies upon Puerperal Fever. Archiv f. path. An;tt.
mid phys. 1>73.
upon Erysipelas. Arch. f. exit, iiath. und
phar., I. 1
BIBLIOGRAPHY. 477
ORTH — Ueber die Form der pathogenen Bakterien. Arch, f . path
Anat., etc., LIX. 532-538. 1874.
. Ueber die Schizomyceteii und ihre Beziehungen zu Krank-
heiten. Arch. f. wissensch. u. prakt. Thier., fieri., III. 1-32.
1877.
OSI.ER and SCHAFER. — Ueber einige in Blute vorhandene Bak-
terien-bildende Massen. Centralbl. f. d. med. Wissensch., XI.
577. 1873.
PASTEUR. — Mem. sur la fermentation appelee lactique. Compt.
rend. Acad. d. sc., XLV. 1857.
. Mem. sur. la fermentation de 1'acide tartarique. Coinpt.
rend. Acad. d. sc., XL VI. 615. 1858.
Xouveaux faits pour servir h 1'historie de la levure lac-
tique. Compt. rend. Acad. d. sc., XL VIII. 337. 1859.
. Experiences relatives aux generat. dites spontanees.
Coinpt. rend. Acad. d. sc., L. 1860.
. De 1'origine des ferments. Compt. rend. Acad. d. sc., L.
1860.
Recherches sur le mode de nutrition des Mucedinees.
Compt. rend. Acad. d. sc., LL I860.
Xouvelles experiences relatives aux generat. dites spon-
tanees. Compt. rend. Acad. d. sc., LI. I860.
. Experiences et vues uouvelles sur la nature des fermenta-
tions. Compt. rend. Acad. d. sc., LII. 1861.
. Animalcules infusoires vivant sans oxygene libre et de-
terminant des fermentations. Compt. rend. Acad. d. sc., LII.
1861.
. Examen de la doctrine des generations spontanees. Ann.
de. Chim. et Phys., 3e serie. LXIV. 1862.
— . Discussion relative a la generat. spontanee. Compt. rend.
Acad. d. sc. 1862.
. Mum. sur les corpuscles organises qui existent en sus-
pension dans I'atmosphere. Compt. rend. Acad. d. sc., LII., et
Ann. de Chim. et Phys., 3e serie, LIV. 1862.
. Examen du role attribuc au gaz oxygene atmospherique
dans la destruction des matieres animales et vegetales apres la
mort. Compt. rend. Acad. d. sc., LVI. 734. 1*03.
Recherches sur la putrefaction. Compt. rend. Acad. d.
sc.. LVF. 1863.
- . Mem. sur la ferment, acetique. Ann. scient. de PEcole
normale, I. 1869.
- . Etude sur le vin. Paris, 1866.
Xouv. etude exper. sur la maladie des vers a soie. Compt.
rend. Acad. d. sc., LXII.
- . Faits nouveaux pour servir a la connaissance de la theorie
des fermentations proprement dites. Compt. rend. Acad. d. sc.
LXV. 1872.
- . Etude sur la biere. 1876.
- . Studies on Fermentation (transl. by F. Faulkner and D.
C. Robb). 8vo, London, 1879.
- . Sur le froid que peuvent supporter la bactcridie et
478 BIBLIOGRAPHY.
d'autres organismes microscopiques, sans perdre leur virulence.
Coinpt. rend. Acad. d. sc., Par., 1879. LXXXIX. 1015.
PASTEUH. — Etiologie du Charbon. Bull. Acad. de med., Par.,
1879. 2. s., VIII. 1222-12:M.
. Kecherches sur 1'etiologie et la prophylaxie de la maladie
charbonneuse dans le departement d'Eure-et- Loire. Rec. de
med. vet., Par., 1879. 0. s., VI. 193-198.
— . Snr les maladies virulentes, et en particulier sur la mala-
die appelee vrUgurement cholera des poules. Compt. rend.
Acad. d. sc. 1880. XC. 239-248.
. De 1'extension de la theorie des germes a 1'etiologie de
quelques maladies communes. Bull. Acad. de med., Par., 1880.
2. s., IX. 435-447.
Sur 1'etiology du Charbon. Compt. rend. Acad. d. sc.,
Par., 1880. XCI. 86-94.
— . Experiences tendant a dernontrer que les poules vaccinees
pour le cholera sont refractaire au Charbon. Ibid., XCI. 315.
— . Sur 1'etiologie des affections charlxmneuses. Ibid., XCI.
455-459.
. Sur la nou-recidive de I'affectiou charbouneuse. Ibid.,
XCI. 5;'.i.
. De 1' attenuation du virus du cholera des poules. Ibid.,
XCI. 07:5-<>SO.
. Nouvelles observationes sur 1'etiologie et la prophylaxie
du charbon. Ibid., XCI. 697.
— . Sur une maladie nouvelle provoquee par la salive d'un
enfant mort de la rage. Compt. rend. Acad. d. sc., Par., 1881.
XCI I. 159-105.
. Sur la longue duree de la vie des germes charbonneux <>t
sur leur conservation dans les terres cultivees. Compt. rend.
Acad. d. sc., Par., 1881. XCII. 209-211.
. Resultats des vaccinations charbonneuses pratiimees pen-
dant les mois de juillet, aout, et septembre 1881. [Communi-
ques a la Soc. d' agric. de Melun, le 26 Janvier 1882.] Arch,
vet., Par., 1882. VII. 177.
De la possibility de rendre les moutons rofractaires au
charbon par la methode des inoculations preventives; avec la
collaboration de MM. Chamberland et Roux. Ibid.. -117-U9.
De 1'attdnuation de virus et de leur retour a la virulence;
avec la collaboration de MM. Chamberland <-t K<mx. Coinpt.
rend. Acad. de sc., Par., 1881. XCII.' 42!» 1:15.
De la possibilite de rendre les moutons refractaires au
charbon par la mothode des inoculations pivvciiliv«-s ; avec la
collaboration de MM. Chamberland et Koux. Coni}»t. rend.
Acad. d. sc., Par., 1881. XCII. i;<i2, U«i«5.
Compte rendu sommaire des i-xpi'-ricncos faites a Pouilly-
le-Fort, pri1^ Mdiin. sur la vaccination charbonucn-i-: ;ur(- l,i
collaboration de MM. Chamberland et Iloux. Coinpt. rend.
Acad. d. sc., Par., 1881. XCII. 1378-1 :XJ.
. Le rouget du pore; avec le collaboration d<* MM. Cii.nn-
b.-rl.ind, Iloux, et Thuillier. Compt. rend. Acad. d. sc.,
X( V. 1120.
BIBLIOGRAPHY. 479
PA^TFTR. — Une statisque au sujet de la vaccination preventive
contie le charbon, portant sur quartre-vingt-cinq mille auimaux.
Compt. rend. Acad. d. sc., 1882. XCV. 1250-1202.
. Reponse au docteur Koch. Rev. scient. Par., 1883.
XXXI. 74-84.
. Nouveaux faits pour servir a la connaissance de la rage ;
avec la collaboration de MM. Chamberland, lloux, et Thuillier.
Bull. Acad. de med., 1882. 2. s., XL 1440-1445.
PASTF.TR et CHAMBERLAXD. — Sur la non-recidive de 1'affection
charbonneuse. Compt. rend. Acad. d. sc., Par., 1880. XCI.
531-638.
PASTEUR et JOUBERT. — Sur les germes des Bacteries en suspen-
sion dans 1 'atmosphere et dans les eaux. Compt. rend. Acad. d.
sc., 206. 1877.
. Sur la fermentation de 1'urine. Ibid., LXXXIII, 5.
. Etude sur la maladie charbouneuse. Ibid., LXXXIV.
900.
Charbon et septicemie. Ibid., LXXXV. 101-115.
PASTEUR, JOUBERT, et CHAMBERLAXD. — Sur le charbon de
poules. Compt. rend. Acad. d. sc.. LXXXYII. 47. 1878.
PAXUM. — Das Putride Gift, die Bakterien, die Putride Infektion
oder Intoxication und Septicaemie. Arch. f. path. Anat. u.
Phys. IX. 1874.
PEABODY, J. L. — Pyaemia without external wound recognized or
recognizable upon careful examination; micrococci in the Mal-
pighian tufts of the kidney. Med. Rec., N. Y., 1879. XV. 306.
PERTY. — Zur Kenntniss kleinster Lebensform. Berne.
Vox PETTEXKOFER, MAX. — Parasitic Nature of Cholera. Zur
Aetiologie der Infectionskrankheiten, 333-352. ' 1881.
PIROTTA and RIBOXI. — Studies on milk. Arch. Lab. Bot. Critt.
Pavia, II., III. 289-345.
PL-SIX. — Histology of Vaccinia. Berlin klin. Wochensch. 1874.
PLACE. — Over den invlced van hoogere warmtegraden op het leven
van bacterien. Werk. v. h. Genootsch. t. Bevord. d. Nat. Ge-
nees. en Heelk. te Amst., III. 126. 1873.
PODE and LAXKESTER. — Experiments on the Development of
Bacteria in Organic Infusions. Proc. Roy. Soc. Lond. 1872-
1^73. XXL 349-368.
POLLEXDER. — Etude microscopique et microchimique du sang de
rate. Vierteljahrschr. f. gerichtl. medizin, XIII. 103. 1855.
POXFICK. — Etudes anatomiques sur le typhus recurrent. Archiv
f. path., Anat. und Phys., LX. 1876.
PorciiET. — Infusoires microscopiques dans les defections alvines
de choleriques. Compt. rend. Acad. d. sc., 23 avril, 1849.
. Huterogenie ou generat. spont. Paris, 1859.
. Compt. rend. Acad. d. sc., XL VII., XL VIII., L., LI.
1859.
. Production des Bacteries et des Vibrions dans les phleg-
masies des bronches, des fosses nasales, et du conduit auditif
externe. Compt. rend. Acad. d. sc., LIX. 748. 1864.
POUCHET et HOUZEAU. — Proto-organismes veget. et anim. nes
480 BIBLIOGRAPHY.
spoil tan ement dans Pair artific. Compt. rend. Acad. d. sc.,
XLVII. !)S2. 1858.
PRAGMOWSKI. — On the History of Development and Ferment-
Action of some Species of Bacteria. Preliminary Communica-
tion. Bot. Zeit. XXX VI I. 409-424. 1879.
. Researches on the Developmental History and Ferment
action of some Species of Bacteria, 58 pp., 2 plates (Svo., Leipzig,
1880).
PRUDDEX. — On the occurrence of tubercles in which the bacillus
tuberculosis is not demonstrable by the ordinary method of stain-
ing. The Med. Record, Vol. XXIII. No. 24, 045.
PUKY. — Versuche iiber septische und mikrococcische Tnfektion.
Arch. f. path. Anat., etc., Berl., LXIX. 32!)-34i). 1877.
DE QUATUEFAGES. — Nouv. rech. faites en 1859 sur les maladies
actuelles du ver a soie. Paris (Masson), 1800.
RABEXHORST. — Flora europoea Algarum aquae dulcis et submarinse.
Leipsig, 18G5.
RAIXEY. — In General Board of Health; Appendix to Rep. of the
Com. for Scient. Inquiry in Relation to the Cholera Epidemic of
1854. 1855.
DE RAXSE. — Du role des microzoaires et des microphytes dans la
genese, 1'evolution et la propagation des maladies. Gaz. med.
de Par., XXII. 025, 071, 713; 1868, XXIII. 597, 025, 079; 1869,
XXIV. 81, 153, 577, 073. 1870.
RAPPIX, GUSTAVE. — Contribution & 1'etude des bacteries de la
bouche, a 1'etat normal et dans la fievre typhoide. Par., 1881.
80 pp. 1 pi. 4°.
RAY-LAXKESTER. — On a Peach-colored Bacterium (B. rubescens).
Quar. J. of mic. Sc., XIII. 1873
RAYXAUD. — luoculabilitc du sang dans un cas de pyohemie spon-
tanee. Gaz. hebdom. de mod. et chir. 1873.
— . De la nature de Terysipele. Union medicale. 1873.
RAYXAUD, M., et O. LANNELOXGUE. — La transmission expt-ri-
mentale de la rage de 1'homme aux animaiix : !•• microbe du virus
rabique (?). Tribune med., Par., 1881. XIV. 49, 01.
Vox I>I:K KKCKK, W. BAKOX. — Sanitiitswesen, IX. Lief. 1. Die
Pilz-Theorie. Milan, 1879. 8°.
Buss. — Upon the Micrococcus. Centralblatt. 1 873.
REIMSC IINI.IDEU. — Ueber den Eiufluss der putriden Intoxication
auf den Blutdruck. Dissert, inaug. Dorpat. Centralb. f. Chirur-
gie, No. 39. 1874.
REIXKH, J. — Influence of Concussion on the Growth of Bacteria.
Pfliiger's Arch. f. Physiol., XXIII. 434.
REUL, A. — L 'inoculation de lamorvedu cheval au chien sj)ecial«'-
ment envisagee comme moyen d'a>ssurer le diagnostic de Pall.', -
tion morvo-farcineuse die/ les ><>lij ,(-de.s suspects. Bull. A<a<l.
roy. de med. de Belg., Brux., 1882. 3. s., XVI. «i:JJ-fi71.
Riui'.i i: T, II. — A Micro (.aia-ilic Invasion of the whole Cortical
Layer of the Brain ( I'.acteria). Plat.- X. fi-. 5. Arch. Path.
Anat. «-t Physiol. (Virchow), LXXX. 505, 606. 1^7^.
RICIIAKD. M. Sur le parasite de la malaria. Compt. rend. Aca<l.
d.sc., X( IV,
BIBLIOGRAPHY. 481
RICHARDSON. — Some New Researches upon the Cause and Origin
of Fever from the Action of Septic Poisons. Brit. Med. Jour'n.,
1875.
RINDFIEISH — Untersuchungen liber Niedere Organismen, Vir-
chow's Archiv, Band LIV. ss. 108, 396.
ROBIN, Cn. — Des fermentations. These d' aggregation. 1847.
. Sur la nature des fermentations en taut que phenomenes
nutritifs, desassimilatioD des plantes Jouru. de 1'Anat. et Phys.,
1875,
ROBERTS, W. — On the occurrence of micro-organisms in fresh
urine. Brit. Med. Journ. Loud , 1881, I. 623-625.
ROBINET et PELLET. —Etude sur les proprietes antiseptiques de
1'acide salicylique. Compt. rend. Acad. d.sc., Par., 1882, XC1V.
1322-1325.
RODET, A. — Contribution a 1'etude experimental de charbon
bacteridien. Lyon, 1881. 8°.
. Sur la rapid! te de la propagation de la bacteridie char-
bonneuse inoculee. Compt. rend. Acad. d. sc., Par., 1882,
XCIV. 1060.
ROMUEGUERE. — The Microscopic Organisms of the Blood. Rev.
Mycol. K. 71-73. 1880.
ROSEXBACH, J. — Gibt es Spaltpilze oder deren Keime in den
Gewben, im Blute, Lymphe und den urspriinglichen Secretionen
gesunder, lebender Menschen und Thiere ? Deutsche Ztschr. f.
Chir., Leipzig, 1880, XIII. 344-364.
ROSENBEUGER, J. A. — Experimentelle Studien liber Septikamie.
Centralbl, f. d. ined. Wissenschr., Berl., 1882, XX. 515.
ROSZAIIEGYI, A. —Experiments on Pasteur's protective inocula-
tion against anthrax in Hungary. Practitioner, Lond., 1882,
XXVIII. 152-160; 227-230.
ROTHE. — Ueber den gegenwartigen Stand der Bakterienfrage.
Memorabilieu, Heilbr., XX. 337-357. 1875.
SAINT-PIKKKE. — De la fermentation et de la putrefaction. These
d'agregation de Montpellier. 1860.
SALISBURY, J. H. — Diphtheria and scarlet fever. Gaillard's M.
J., X. Y., 1882, XXXIII. 401-424, 7 pi.
SALMON*. — Investigations of swine-plague and fowl-cholera. Sec-
ond Report to the Commissioner of Agriculture. Dept. of
Agricul. Report, 1880, 387-454, 9 pi.
. On the production of immunity from contagious fevers
by inoculation with diluted virus. Med. Rec., N. Y., 1883,
XXII. 370-373.
SAMUEL. — Action of Putrefactive Processes upon the Living Or-
ganism. Arch. f. exper. pathol. und pharm., I. 1873.
SANDKKSON. J. B. — Origin and Distribution of the Microzymes
in Water, and in the Tissues and Liquids of the Organism.
Quart. Journ. of Mic. Sci., Oct., 1871.
. Lectures on the Occurrence of Organic Forms in con-
nection with Contagious and Infectious Diseases. British Med.
Journ., 1875.
. New Experiments upon the Destruction of the Virus of
Putrid Liquids by Filtration through Cylinders of Clay. Wiener
medizinische Jahrbucher, heft III. 1876.
4S2 BIBLIOGRAPHY.
SANDERSON, J. B. — Atmospheric Germs. Roy. Soc. of London,
1876.
. The pathology of inflammation. Med. News, Lond..
1882. II. 75, 87, 103, 115, 123, 134, 147, 158, 172, 182,
DE S,u»ri:i:. — Recherches sur la vegetation, 143. 1804.
ScHi.ni>iN(i and MUXTZ. — Reclierches sur la nitrification par les
fermentes organises. Compt. rend. Acad. d. sc., LXXXVI.
892-895, 1878.
. Reclierches sur la nitrification. Ibid., LXXXIX. 891-
894; 1074-1077, 1880.
SCHUTZ and LOEFFLER. — Aetiology of Glanders. Deutsches med.
Wochensch., No. 51, 1882.
SOHNKTZLER, J. B. — Chromogenous Schizomycete on Cooked
Meat. Bull. Soc. Vand. Sci. Nat., XVIII. (1882) 117-119.
Abstr. J. 11. M. S., 1882, October, G55-G5G.
. Diffusion of Bacteria. J. R. M. S., Oct., 1882, 658-059.
SCHROETEK. — Ueber einige durcli Bacterien gebildete Pigniente.
Beitr. z. Biol. d. Pflanz. 1, 2, Heft 109-126. 1870.
Si iinzKXBEKGEU. — Les fermentations. Paris, 187-").
SEDILLOT. — De 1'infection purulente ou pyohemie. Paris, 1849.
SEMMEK. — Der Milzbrand und das Zilzbrand-contagium. Jena,
1>S2, 83pp., 1 pi. 8°.
DE SEYXES. — Des rapports des Mycodermes et des levures. Bull.
Soc. Bot. Fr., XV. 1868.
— . Sur le Mycoderma vini. Compt. rend. Acad. d. sc. 1868.
— . Note sur les Mycodermes de 1' urine des diabe'tiques. Journ.
de 1'Anat. et Phys. norm., etc., VI. 67. 1869.
. Sur les transformations des Bacteries et des Mucedinces
en Levures alcooliques. Compt. rend. Acad. d. sc., janv., I.s72.
SEUVEL, II — Sur la naissance et 1'evolution des Bacteries dans
les tissus organiques mis k 1'abri du contact de Pair. Compt.
rend. Acad. d. sc. 1*7 1.
SIEDAMGROTZKY. — Des Bacteries du sang de rate. Deutsch.
ztschrift. fiir Thierm. und vergl. Path., 1. 1875.
SitiNOL. — Presence des bacturies dans le sang. Compt. rend.
Acad. d. sc., LVII. m 1863.
SMITH, ANGUS. — Disinfectants and disinfection. Edinburgh,
1869.
SOCOLOFF. — Zur Pathologic des acuten Milztumors. Virchow's
Archiv, lid. M. 1870.
SOYKA. — On the Passage of Schizomycetes into the Air. Sitz. d.
k.-bayer. Akad. d. Wiss. Miinclien, Is?!), 1 In 1 17.
SPAM. AN/AM. Opusmles de physique, aiiimale «-t v^vtale. 1799.
8TKRKBEBG, G. M. — An inquiry into the nature of the yellow-
fever poison, etc. Am. Journ. of the Med. Sciences, No. CXXX.
n. s. (A].ril, 1*73).
Kxamination of the Mood in yellow fever: cxiH-rini'Mifs
upon anitnals. ctr>. In Pn-lim. Rcpurt i.f I lav. Vdl<i\\ l'c\-cr Coin.
Supplement to National Board of Health Bulli-tin. Washington,
. Expcrim«-iits tlc-'i^nod to <<--t tin- v:ilm- nf (vrf.-iin ^asi-mis
an<! v«.l;,til«- cliMi,f,.rt:iiit>. Nat. 15. 1. IK-alth Bull., \Vash., 1879.
Vol 1. \ . 29, 80, 37 and 47.
BIBLIOGRAPHY. 483
STERXRERG. O. M. — Experiments with disinfectants. Johns Hop-
kins l.'tiiv. stud. biol. lab., Bait , 18*2, II. No. 2, 2ol-i>12. Also,
Nut. Bd. Health Bull., U ash., 1881, Vol. 111. Xo. 4.
. A fatal form of septica-mia in the rabbit, produced by the
subcutaneous injection of human saliva. Johns Hopkins t'uiv.
stud. biol. lab.. Bait., 1882, II. Xo. 2, 183-200, 1 pi. Also,
Xat. Bd. Health Bull. Vol. II. 781.
. Bacillus anthracis. X. Y., 1881, Thompson and Moreau,
4 pp., 1 pi. 8°. [Repr. from Am. Month. Micr. Journ., 1881.]
Special Report to Xational Board of Health : experi-
mental investigations relating to the etiology of the malarial
fevers. Xat. Bd. Health Bull, Wash., 1881-2, III. (Suppl.
Xo. 14, 1-11, 2 pi., 2 charts.)
. Is tuberculosis a parasitic disease? Med. News, Phila.,
1882. First Paper, July 1, pp. 6-7. Second Paper, July 22. pp.
87-89. Third Paper. Sept. 10, pp. 311-314. Fourth Paper, Xov.
18, pp. 501-566. Fifth Paper, Dec. 30, p. 30.
. The value of carbolic acid as a germicide as established
by experimental data. Med. Rec., X. Y., 1882, XXII. 314-317.
The recognition of micrococci. Med. Rec., X. Y , 1882,
XXI. 308 370.
. Induced septicaemia in the rabbit. Am. Journ. Med. Sc.,
Phila., 1882, LXXXIV. 69-76.
A contribution to the study of the bacterial organisms
commonly found upon exposed mucous surfaces, and in the ali-
mentary canal of healthy individuals. Proc. Am. Asso Adv.
Sc., 1881, Salem, 1882, XXX. 83-91. Also in Vol. II. Xo. 2.
Studies from Biolog. Lab., Johns Hopkins Univ.-, Bait., 157-181,
3 pi.
. Virulence of normal human saliva. Medical Times, Xov.
pp. .-
. The Micrococcus of Gonorrhoea! Pus. Infective virulence
not due to the presence of this parasitic micro-organism. Medi-
cal Xews, Phila., Vol. XLII. Xos. 3 and 4. (Jan. 20, 1>63. pp.
07-70. and Jan. 27, pp. 96-99.) Second Paper, Ibid., March 24,
1883, p. 32:5.
STRAPS et CIIAMBERLAXD. — Sur le passage de la bacteridie char-
bonneuse de la mere au fcetus. Gaz. hebd. de mud., Par..
2. s., XX. 167.
STRAUSS, M. — Vaccinal Micrococci. J. R. M. S., Oct..
p. 6'il.
SZPILM AN. — Ueber das Verhalten der Milzbrand bacillen in Gazen.
Ztschr. f. physiol. Chem., Strasb., 1880, IV. 350-370.
TALAMOX, C. — Note sur le microbe de la diphtheric. Bull. Soc.
anat. de Par., 1881. LVI. 44, 68.
TAPPKIXEU. — XIMK- experimentelle Beitriige zur Inhalationstuber-
culose der Hunde. Arch. f. path. Anat., etc., Berl., 1880,
LXXXII. 353-369.
Zur Frage der Contagiositat der Tuberculose; experi-
rnt^rsuchiingen. Deutsches Arch. f. Klin. Med., Leipz.,
. XXIX. oD.VUOO.
T^DEXAT, E. — Etude critique sur la septicemie et la pyohemie
484 BIBLIOGRAPHY.
(clinique et experimentation). Par., 1879. A. Delahaye et
cr, 124 pp. s°.
Tuix, G. — Bacteria decalvans. Proc. Roy. Soc., XXXI. 502-503.
1881.
. Absorption of Pigment by Bacteria. Proc. Roy. Soc
XXXI. 503-501. 1881.
VAX TIEGHEM. — Recherches sur la fermentation de Puree et de
1'acide hippurique. Ann. scient. de 1'Ecole uormale, I., et Compt.
rend. Acad. d. sc., LVIII. 1801.
— . Sur le Bacillus amijlobacter et son role dans la putrefaction
des tissus vegetaux. Bull. Soc. Bot. Fr., XXIV. 1877.
. Identite du Bacillus Amylobacter et du Vibrion butyrique
de M. Pasteur. Compt. rend. Acad. de sc., Par., 1879, LXXX1X.
5-8, and 1102-1104.
. On the Fermentation of Cellulose. Bull. Soc. Bot. Fr.
XXVI. 2.3-30. 1880.
. Green Bacteriacea and Colorless Phycochromacese. Bull.
Soc. Bot. France, XX VII. 174-179. 1880.
Bacteria living at High Temperatures. Bull. Soc. Bot.
France, XXVIII. 55-56. 1881.
TIEGAL, E. — Ueber Coccobacteria Septica in gesunden Wirbel-
thierkorpern. Arch. f. path. Anat. u. Phys., LX. 1874.
TIGRI. — Sur la presence d'infusoires du genre Bacterium dans le
sang hutnain. Compt. rend. Acad. d. sc., LV1L, 633. 1863.
. Note sur un nouveau cas de Bacterie dans le sang d'un
homme mort de fievre typhoide. Compt. rend. Acad. d. sc.,
LVII. 833. 1863.
. Nouvelles recherches sur les maladies characterisees par
la presence des Bacteridies. Compt. rend. Acad. d. sc.. LXII.
291. 1866.
TILLMANXS, II. — Experimented und anatomische Untersuch-
ungen iiber Erysipelas. Arch. f. Klin., Chir., BerL, 1879, XXIII.
437-519, 1 pi.
TOMMASI-CRUDELI, C. — Der Bacillus Malarirc in Erdboden von
Selinunte und Campobello. Arch. f. exper. Path. u. Pharmakol..
Leipz., 1880, XII. 225-230.
— -. Bacillus Malarias of Selinunte and Campobello. Atti R.
Accad. Lincei (Transmit.,), IV. 110-113, 653-696. 1880.
. De la distribution des eaux dans le sous-sol romain et de
la production naturelle de la malaria; rapport a 1' Acad. roy. des
Lincei de Rome. [Transl. by E. Vaisson.J J. d'hvg., Par.,
1 ^0, V. 459-462.
— . Nature of Malaria. Atti R. Ac ad. Lincei, Transunti,
IV. (1881) 19-21; 110-113; 653-696. 1880.
— and KLEBS. — On the Nature of the Specific Agent which
produce* Malarial Fever. Trans. R. Acad. Lincei, III. 216-220.
1870,
TOUSSAINT. — Sur les bacteridies charbonneuse. Compt. rend.
Acad. d. sc., LXXXV. 415.
. Du im'chanism de la mort consecutive a 1'inoculation du
charbon an lupin. Ibid., LXXXV. 1076.
— . Preuves de la nature para-sitaire du charbon, etc. Ibid.,
LXXXVI. 725.
BIBLIOGRAPHY. 485
- VINT. — Du charbon chez le cheval et le chien; Action phlo-
:ie du sang charbonneux. Corapt. rend. Acad. d. sc.,
LXXXVL 833. 1
. Sur une maladie a forme cbarbonneuse causee par un
noLiveau vibrion aerobie. Couipt. rend, Acad. d. sc., LXXXV1I.
69. 1878.
. Recberches experimentales, sur la maladie charbonneuse.
Lyon, 187i». 130 pp., 3 pi. 4°. No. 17.
. De riiiiniunite pour le charbon, acquise h la suite d'in-
oculations preventives. Compt. rend. Acad. d. sc., Par., 1880,
XCI. 13.3-137.
. Ideutite de la septicemie experimentale aigue et du
cholera des poules. Compt. rend. Acad. de sc., Par., 1880,
XCI. 301-303.
. Sur quelques points relatifs a 1'immunite charbonneuse.
Conip. rend. Acad. d. sc., Par., 1881, XCIII. 163.
De 1'immunite pour le charbon; note en reponse a M.
Colin. Bull. Acad. de med., Par., 1881, 2. s., X. 301-325.
Sur la parasitisme de la tuberculose. Compt. rend. Acad.
d. sc., Par., 1881. XCIII. 350-353.
. Sur la cultui'e du microbe de la clavelee. Compt. rend.
Acad. d. sc., Par., 1881: XCII. 362-364.
Sur un precede nouveau de vaccination du cholera des
poules. Ibid., 219-221.
. Sur la contagion de la tuberculose. Compt. rend. Acad.
d. sc., XCIII. 741.
TIIAUBE und GSCHLEIDEX. — Ueber Faulniss und den Widerstand
der lebenden Organismen gegen dieselbe. Berlin klin. Wochens.
Xo. 37. 1874. "
TRASBOT, L. — Maladie dite des chiens; de sa contagion et de la
vaccination comme moyen de la prevenir ou de 1'attenuer. Arch.
vet., Par , 1879, IV. 161-169.
. Expediences sur la transmissibilite de la diphthe'rie des
volailles aux autres especes animales. Ibid., 121-124.
TROISIER. —Etude du sang de 1'erysipele. Bull. Soc. Anat. VIII.
1875.
TYNDALL. — A Combat with an Infective Atmosphere. Pop. Sc.
Month., X. Y., X. 641-654. 1877.
. Essays on the floating matter of the air in relation to
putrefaction" and infection. X. Y., 1882. D. Appleton & Co.,
o37 pp. 8°.
URLICHS. — Ueber Vegetation von Pigment-Bacterien in Verband-
^stoffen. Arch. f. klin. Chir. Berl., XXIV. 303-308. 1879.
VALLIX. — Sur le resistance des Bacteries a la chaleur. Ann. d'
Hyg. Public, 2* serie. XLIX. 259. ISM).
. Traite des de'sinfectants et de la de'sinfection. Par.,
^ 1883, 808pp. 8°.
VIGXAL. — Sur la persistance des bacilles de la tuberculose dans
les pieces anatomiques. Compt. rend. Soc. de biol., Xo. 16,
May 5, 1883, p. 314.
VILT.EMIX. — Rapport sur la longue duree de la vie des germes
charbonneux et leur conservation dans les terres cultivees; au
486 BIBLIOGRAPHY.
nom d'une commission. Bull. Acad. de med., Par., 1881, 2. s.,
X. 822-628.
AV.u IIKMIKIM, EUGENE. — Etude expe'riinentale sur la septicite et
hi virulence du sang charbouneux. Nancy, 1880, 78 pp. 4°.
WALDSTKKIN, L. — Em Beitrag Zur Biologie der Bukterien. Arch,
f. path. Aiiat., etc., Berl., 1879, LXXVII. 84-68, 1 pi.
WALDYKU. — Ueber das Vorkommen von Bakterien bei der diph-
th-ritischeii Form des Puerperalfiebers. Arch. f. Gynack, III.
293-297. 1871.
AY A KM i NO. — Om nogle ved Danmarks Kyster lavende Bakterier.
Copenhagen, 1876.
\VASSILIKFF, N. P. — Beitrag zur Frage iiber die Bedingnngen,
uut'-r diMien es zur EntwickeloDg YOU Mikrokokken Colonien in
den Hint Classen Koinmt. Centralbl. f. d. med. Wisseuschr.,
Berl., 1881. XIX. 929-9:32.
AVKIGERT, — Ueber den gegenwartigen Standpunkt der Contagien-
frage mit besonderer Bernckfiichtigung der HCIKMI Forsi'liung.-n
iiber Milzbrand. Jahresb. d. schles. Gesellsch. f. vaterl. Cultur.,
Bresl., 1878, LV. 317-322.
"\VEIL, A. — Fungi in Diseases of the Teeth. Zur Aetiologie der
Infectionskrankheiten, I. 18-198. 1881.
AVi.iiNK ii. [Inters uchungen iiber Bacterien. Beitriige zur Bio-
logie der Pflanzen, Bd. III. Heft 1, 105. 1879.
. Action of Dry Heat and of Sulphurous Acid on the Bac-
teria which accompany Putrefaction. Nature, XII. 311, 312,
(Abstract from Centralblatt f. die Med. Wiss.). 1*7!).
. The Aromatic Products of Decomposition in their Influ-
ence on the Srlii/omvceU'S. Arch. path. Auat. und Pliys.
LXXVIII. 51-83. 1879.
. Experiments on Infection with Micrococcus prodigiosus.
Beit. Biol. Pilau/,. III. 105-118. i860.
. Ueber Bacterientodtnng. Verhandl. d. Berl. med. Ge-
sellsch. (1879-80) 1881, XI. pt. 2, 57-71.
. Ueber den gegeuwiirtigen Stand der Desinfektionsfrage.
Wi-n. Klinik, 1880, VI. 199-220.
. Studien und Erfahrungen iiber den Typhus abdominalis.
Ztschr. f. Klin. M«-d.. Berl., 1882, IV. 40-78, fc58-890, -l!>s-:,:jl.
. Dcsinfectionslehre zum praktischen Gerbiaucli auf kritis-
fln-r und expfiiiiH'Mteller Grundlage, 2 Aufl. Weiu and Leipz.,
L882, 858 pp. 8°.
AVi.KMT/. INVAN-. — Ueber die Wirknng <lor Antiseptica auf unge-
fonnt.'. F.-niiente. Dorpat, 1880, C. Mattieson, 93 pp. 8°.
AVi \KT. — Mt'inoires d'uu microbe. 2 c-d. Par., 1882. Coccoz, 128
].p. 8°.
AVn (ii.ni. — Upon the Spir&itm of Obermeier. Klin. Wochens.
1-7:;.
AVu in i M. E. — D'-r Milzbrand, mechanisch, physisch und chem-
is.-h .-rklart. Li. -nit/, 1881. 8°.
.i M<. — Xonvcllcs n'cherclies sur la pleuro-pneumonie ex<n-
dativc i]i> ]'.•>],;•<•.• bi>vin«' ut sur 1'inoculation ]»n;vcntivc de cette
nialadir. Hull. Acad. roy. de med. de Belg., Brox., 1880, 3. s.,
XIV. •_'!!
BIBLIOGRAPHY. 487
WILLEMS. — De la non-recidive de la peripneumonie contagieuse
des betes bovines. Bull. Acad. roy. de med. de Belg., Brux ,
1881, 3. s., XV. 156-170.
. Inoculation critere de la peripneumonie contagieuse. Bull.
Acad. de med., Par., 1881, 2. s., X. 1100-1105. Also, BuU. Acad
roy. de med. de Belg., Brux., 1881, 3. s., XV. 584-598.
. Communication relative a 1'inoculation preventive de la
pleuropneumonie contagieuse des betes bovines. Bull. Acad. roy.
de med. de Belg., Brux., 1882, 3. s., XVI. 62-73.
WOLFF. — Injection of Microscopic Organisms. Centralblatt.
1873.
. Zur Bakterienlehre bei accidentellen Wundkrankheiten.
Arch. f. path. Anat., etc., Bed., 1880, LXXXI. 193-277, 385-
420.
WOOD and FORMAD. — Report upon the effect of inoculating the
lower animals with diphtheritic exudation. Rep. Nat. Bd.
Health, 1880. Wash., 1882, II. 374-386.
WORTMANN, J. — Diastatic Ferment of Bacteria. Zeitschr. f.
phys.-Chim., VI. 287.
OSCAR. — Ueber typhb'se Erkrankungen, durch Fleischgenuss
Correspondenzblatt der Schweiz, Aertze, XI. Jahrgang, 1881.
ZIEGLER. — The Schizomycetes, or Bacteria. Chap. XXX. in Text-
book of pathological anatomy and pathogenesis. London and
New York, 1883.
ZWEIFEL, P. — Untersuchungen iiber die wissenschaftliche Grund-
lage der Antisepsis und die Entstehung des septischen Gifts.
Ztschr. f. physiol. Chem., VI. 386-421. Strassb., 1882.
SUPPLEMENT TO BIBLIOGRAPHY.
(Brought up to June 30, 1884.)
ARLOIXG, CORNEVIX, et THOMAS. — Le charbon bacterien (char-
bon symptomatique) pathogenic et inoculation preventive.
Lyon, 1883. 8°.
. Etudes complementaires sur le charbon symptomatique on
bacterien. J. de med. vet. et zootech., Lyon, 1883, 3. s., VIII.
393-413.
BABES, V. — Etude comparative des bacteries de la lepre et de la
tuberculose. Compt. rend. Acad. d. sc., Par., 1883, XCVI. 124G-
1249.
. Observations sur la topographic des bacilles de la lepre
dans les tissus, et sur les bacilles du cholera des poules. Arch.
de physiol. norm, et path., Par., 1883, 2. s., II. 41-51, 1 pi.
. Observations sur quelques lesions infectieuses des mu-
queuses et de la peau (diphtherie, charbon, mycose intestinal,
morve, fievre.typhoide, cholera, gangrene, sueur rouge, verrues).
J. de Pan at. et physiol., etc., Par., 1884, XX. 39-70, 4 pi.
488 BIBLIOGRAPHY.
BAUMGARTEX. — Ueber pathogene pflanzl. Mikro-organismen.
Die pathogenen Hyphomyceten. Berl. 8°, 1884.
. Ueber ein neues Heine ulturverfahren der Tuberkelbacillen.
Centralbl. f. d. ined. Wissensch. No. 22, 1884, p. 369.
BELFIELD, W. T. — On the relations of micro-organisms to disease:
the Cartwright lectures, delivered before the Alumni Assoc. of
the College of Physicians and Surgeons, N. Y., Feb., 1883.
Chicago, 1883. 12°.
Bienstock, B. — Ueber die Bakterien der faeces. Fortschr. d. med.,
Berl., 1883, 1, 609-615.
BOCHFOXTAIXE. — Etude experimentale sur 1'action microbicide
du sulfate de cuivre. J. de pharm. et chim., Par., 1883, 5. s.,
VIII. 401-412.
BRUYLAXTS et VEXXEMAX. — Le je'quirity et son principe phlogo-
gcne. Bull. Acad. roy. de med. de Belg., Brux., 1884, 3. s.,
XVIII. 147-179.
CAMPAGXA, R. — Sur la transmissibilite de la lepre aux animaux.
Arch. ital. de biol., V. 185-189.
CHAMHEHLAXD, C. — Role des microbes dans la production des
maladies. Par., 1883. 8°.
. Le charbon et la vaccination charbonneuse d'apres les tra-
vaux recents de M. Pasteur. Par., 1883, 323 p. 8°.
CHAMBERLAXD et Roux. — Sur 1'attenuation de la bacteride
charbonneuse et de ses germes sous Pinfluence des substances
antiseptiques. Compt. rend. Acad. d. sc., Par., 1883, XCVI.
1410-1412.
CHAUVEAU, A. — Du role respectif de 1'oxygene et de la chaleur
dans 1'attenuation du virus charbonneux par la methode de M.
Pasteur; theorie generate de 1'atte'nuation par 1'application de ces
deux agents aux microbes aerobics. Compt. rend. Acad. d. sc.,
Par., 1883, XCVI. 1410-1412.
. De 1'inoculation preventive avec les cultures charbon-
neuses attenuees par la methode des chauffages rapides.
Compt. rend. Acad. d. sc., Par., 1883, XCVII. 1242-1245.
Hid. 1 31)7-1400.
. De la preparation en grandes masses des cultures attenuees
par le chauffage rapide pour 1'inoculaiion preventive du sanic do
rate. Compt. rend. Acad. d. sc., Par., 1884, XCVIII. 73-77.
MM. 126-131.
CORNIL, V., et A. BERLIOZ. — Experiences sur Pempoisonnement
par les bacilles de la maceration du jequirity. Arch, de physiol.
norm, et path., Par., 1883, 3. s., II. 412-441, 2 pi.
. Note sur Pempoisonnement des poules par les bacilles
du jequirity. Bull. Acad. de med., Par., 1884, 2. s., XIII. 211-
214.
CORXIL et BABES. — Contributions a 1'etude des inflammations
liees a la presence des microbes; poripnoumonie contagieuse;
pneumonic rubdolique; £ryth6me cut;inc du rnutr"t des pores.
An-h. <1<; physiol. norm, et path., Par., l^s:}, 3. s.. II. 228-216.
EDKIMII. C. .1. I)<T Typhus-bacillus und die intestiiiale Infection.
Samml. Klin. Vortr., Lcipx . 1888, X". 22fJ.
FEHLEISEX. — Ueber die Ziichtung der Erysipelkokken auf Kiinst-
BIBLIOGRAPHY. 489
lichem Nahrboden und ihre Uebertragbarkeit auf den Menschen.
Sitzungsb. d. phys.-med. Gesellsch. zu Wiirzb., 1883, 9-13.
FISCHER, B., und B. PROSKAUER. — Ueber die desinfection mit
Chlor und Brom. Mitth. a. d. k. Gsudhtsarate, Berl., 1884,
II. 228-308.
FLUGGE, C. — Fermente und Mikroparasiten. Leipzig. 1883.
8°.
FRIEDLAXDER, C. — Die Microkokken der Pueumonie. Fortschr.
d. med., Bed., 1883, I. 715-733, 1 pi.
GAFFKY. — Zur Aetiologie des Abdominaltyphus- Mitth. a. d. k
Gsndlitsamte, Berl., 1884, II. 372-420.
— . Ein Beitrage zum Verbal ten der Tuberkelbacillen im
Sputum. Mitth. a d. k. Gsndhtsamte, Berl., 1884, II. 126-130.
GAUCHER, E. — Culture des bacteries de la lepre. Compt. rend.
Soc. de biol. 1881, Par., 1882, 7. s., III. 201.
GAUTIER, A., et A. ETARD. — Sur les produits derives de la fer-
mentation bacterienne des albuminoides. Compt. rend. Acad. d.
sc., Par., 1883. XCVII. 263-267.
GRADLE, H. — Bacteria and the germ-theory of disease: eight
lectures delivered at the Chicago Medical College. Chicago,
1883. 8°.
GROVE, B. A. — A synopsis of the Bacteria and Yeast Fungi.
Lond., 1884.
HAUSER. — Ueber das Vorkommen von Mikro-organismen im
lebenden Gewebe des normallen tierschen Organismus. Centralbl.
f. d. med. Wissensch. Xo. 21, 1884, p. 355.
KOCH, R. — Bericht der nach Egypten entsendeten deutschen
Cholera-Commission. Mitth. d. Ver. d. . Aerzte in Xied.-Oest.,
Wien, 1883, IX. 258-264 (transl. Med. Times and Gaz., Lond.,
1883, II. 447).
. Der vierte Berichte des Leiters der dentschen wissen-
schaftlichen Commission zur Erforschung der cholera. Wien.
med. bl. 1884, VII. 146-148.
. Fiinfter Bericht. Ibid. 235-237.
. Sechster Bericht. Ibid. 360-363.
. Siebenter Bericht. Breslau, aerztl. Ztschr., 1884, VI. 99.
. Weiteres iiber die Cholera-bacillen. Wien. med. Bl. , 1884,
VII. 464.
Die Aetiologie der Tuberkulose. Mitth. a. d. k. Gsndhts-
amte, Berl., 1884, II. 1-88, 10 pi.
KOCH, R., GAFFKY, und LOEFFLER. — Experimentelle Studien
iiber die kiinstliche Abschwachung der Milzbrandbacillen und
Milzbrandinfection durch Fiitterung. Mitth. a. d. k. Gsndhts-
^amte, Berl., 1884, II. 147-181.
KLEIN, E. — On a morphological variety of Bacillus anthracis.
Quart J. Micr. Sc., Lond., 1883, n. s., XXIII. 260-267, 1 pi.
. The Bacteria of Swine Plague. J. of PhysioL, Lond.,
V. 1-13.
— . Micro-organisms and disease. Practitioner, Lond., 1884,
XXXII. 170-186; 241-264; 321-352.
. Eiu Beitrag zur Aetiologie der Jequirity-Ophthalmie.
Centralbl. f. d. med. Wissensch., Berl., 1884, XXII. 113-116.
490 BIBLIOGRAPHY.
LETZERICH, L. — Experimentelle Untersuchungen iiber die Aetiolo-
gie des Typhus abdominalis; mit besonderer Beriicksichtigung
der Trink- und Gebrauchswasser. Arch. f. exper. Path, u. Phar-
makol., Leipz., 1883, XVII. 218-260, 1 pi.
LOKFFLER, F. — Untersuchungen iiber die Bedeutung der Mikro-
organismen fiir die. Entstehung der Diphtlierie beiin Mensch'en,
bei der Traube und beim Kalbe. Mittli. a. d. k. Gsndhtsamtt4,
fieri., 1884, IL. 421-499.
MALASSEY, L., et \V. VIGXAL. — Persistance de la puissance patho-
gcnique des bacilles dans les crachats desseches des phthisiques.
Compt. rend. Soc. de biol., Par., 1883, 7. s., IV. 650.
. Tuberculose zoogloeique (forme on espece de tuberculose
sans bacilles). Arch, de phvsiol. norm, et path., Par.. 1883, 3. s.,
II. 369-412, 2 pi.
MIQUEL, P. — Les organismes vivants de 1'atmosphere. Par.,
1883. 8°.
. Antiseptiques et bacteries (from Annuaire meteorol. de
1884). Monit. sclent., Par., 18-Sl, 3. s., XIV. 170-178.
OSEL, K. — Das Anthraxvirus. Centralbl. f. d. med. Wissensch.
No. 23, 1884, p. 401-404.
PASTEUR. — La vaccination charbonneuse. Reponse £ un me-
moire de M. Koch. Par., 1883, 32 p. 8°. [llepr. from Rev.
scient.]
. Xouvelle communication sur la rage; avec la collaboration
de MM. Chamberland et Roux. Compt. rend. Acad. d. sc., Par.
1884, XCVIII. 457-463.
PASTKUR et THUILLIER. — La vaccination du rouget des pores &
1'aide du virus rnortel attenue de cette maladie. Bull. Acad. do
m.-d., Par., 1883, 2. s.. XII. l:;5!)-13(i!i. Also: Compt. rend.
Acad. d. sc., Par., 1883, XCVII. 1163-1100.
PERRONCITO, E. — De la transmission du charbon par les voies de
la digestion. Arch. ital. de biol., V. 178-181.
PoiiL-Pixcus. — Mikrokokken an den Epidermisschuppen von Sclmr-
lachkranken. Centralbl. f.d. med. Wissensch., fieri., 1883, XXI.
041-643.
1! }-. i \scii. — Bacteria and Microscopical Algre on the Surface of
Coins. J. Roy. Mic. Soc. Loud., 2. s., I V. 42s-|30._
RICHARDS, V. — Some experiments with choli-ra dejections on the
lower animals. Indian M. (iax., Calcutta, 1881. XIX. 80; 92.
K.H'.I.V, C. — Germes. Diet, encycl. d. sc. med., Par., 1883, 4. s.,
VIII. 556-617.
SALMON. I). E. — Investigations of fowl cholera. Dep. Agric.
Contag. <lis. dom. animals, \Va>li., l>»s:J. H-53.
SALVIOI.I und / \-I.I.IN. I't-lii-r den MikrokokktU und d'n1 Patho-
genesc d--r «-n)iij.MS«Mi Pii«Minn»ni<'. Centralbl. f. d. nn-d. \Vis-
sensch., P..M-!.. 1888, XXI. 721-721.
SATTI u:. II. — IVU-r <li'-. Nfttnr der Jeqnirityophthalmie. Klin.
Mi.nat^bl. f. Augenh., Stuttg., 1803. XXI. 207-227.
SAUVA«;I-:. V. — De la valour diaurnosli(pii' d" la prrscwc d--s
bacill.-s dc Korh dans l«-s ci'acliats Pur., 1»3. Is p.
8TRAD8. L<: rh.)i.'ra <1«; Is-:', ,.,, Ivj-vjtt.-: ra|>|><>it MIT !•• dioli'ra
d'figypte en 1883, .ulrcssr a .M. le Minislre du C'oinintMrc an
BIBLIOGRAPHY. 491
nom de la mission frai^aise. Union me'd., Par., 1883, 3. s.,
XXXVI. 923-927.
THIN, G. — On the bacillus of leprosy. Med.-Chir. Tr., Lond.,
1663, LXVI. 315-328, 2 pi.
TOBPPEB, P. — Die neueren Erfahrungen iiber die Aetiologie des
Milzbrandes. Jena, 1863. 57 p. 8°.
WKICIISKLBAUM, A. — Experiinentelle Untersuchungen iiber In-
halationstuberculose. Med. Jahrb., Wieu, 1883, 169-211.
, A. — Ueber Tuberkelbacillen im Blute bei allgemeiner
akuter Miliartuberkulose. Wien. med. Wchnscbr., 1884, XXXIV.
333-330.
WKKXICH, A. — Ueber Desinfectionskriterien. Verhandl. d. Berl.
med. Gesellsch. (1881-2), 1883, XIII. pt. 2, 158-178.
. Desinfektionsveilaliren. Wieu. med. Presse, 1883, XXIV.
965, 992.
WOOD and FARMAD. — Memoir on the nature of Diphtheria. Ap-
pendix A. Report of the National Board of Health for 1882,
Washington, 1864.
ZIEGLEU, C. — A text-book of general pathological anatomy and
PATHOGENESIS. Translated and edited for English students by
Donald Macalister. N. Y., 1883, 387 p. 8°.
ZIEHL, F. — Ueber das Vorkommen der Pneumoniakokken im
pneumonischen Sputum. Centralbl. f. d. med. Wissensch.,
Berl., 1883, XXI. 433-436.
ZOPF, W. — Die Spaltpilze. Breslau, 1884. 8°. 101 p., illustrated.
INDEX.
ABSCESSES, bacteria in, 449.
Acetic acid, antiseptic action of, 215.
Acetic ferment, 83.
Aerobies, 116.
Aeroscopes, 200.
Alcohol, germicide power of, 215.
Algae, bacteria classed with, 56.
Aluminium acetate, 216.
Aluminium chloride, 216.
Ammonia, does not dissolve bac-
teria, 54.
germicide power of, 216.
source of, 149.
Anaerobies, 116.
Anthrax, 265.
bacillus of, 270.
spores of, 270.
Aqueous humor as a culture-fluid,
165.
Aromatic products of decomposition,
216.
Arsenious acid, 216.
Atmospheric bacteria, collection of,
197.
Attenuation of virus :
method of Pasteur, 202.
of Toussaint, 204.
of Chauveau, 205.
by intravenous injection, 206.
by chemical reagents, 206.
BACILLUS, 87.
B. anthracis, 88.
development of, from B. subti-
lis (?), 253.
Bacillus malarise, 319.
action of quinine upon, 327.
in blood of man, 320.
Bacillus of leprosy, 332.
of malignant oedema, 336.
of tuberculosis, 391.
of typhoid fever, 408.
B. amylobacter, 88.
B. des infusions, 90.
B. du levain, 89.
B. du vin tourne, 90.
B. glaireuse, 90.
B. intestinal, 89.
B. ruber, 89.
B. subtilis, 87.
B. utilis, 89.
Bacteria in surgical lesions, 442.
Bacterium, 80.
genus established by Davaine,
18.
B. seruginosum, 85.
B. catenula, 82.
B. cyaneum, 73.
B. lineola, 81.
B. littoreum, 81.
B. luteum, 73.
B. prodigiosum, 73.
B. punctum, 82.
B. termo, 81.
B. sulphuratum, 86.
B. violaceum, 74.
B. xanthinum, 85.
Bacterio-purpurine, 38.
Bastian, views and experiments of,
103.
494
INDEX.
Baumgarten, method of staining
tubercle bacilli, 191.
Beggiatoa, 91.
B. alba, 91.
B. arachnoidea, 91.
B. leptomitiformis, 91.
B. minima, 91.
B. mirabilis, 91.
B. uivea, 91.
Beuzoic acid, antiseptic value of,
217.
Bert, experiments of, 269.
Billrotb, views of, 22.
Blood, normal, free from bacteria,
108, 261.
method of obtaining, 161.
Blood-serum as a culture-medium,
162.
method of sterilizing, 163.
Bockhart, experiments of, 311.
Bokai, experiments of, 310.
Boric acid, antiseptic value of, 122,
217.
Bromine, germicide power of, 218.
CAMPHOR, antiseptic value of, 218.
Carbolic acid, action of, upon bac-
teria, 122, 219.
Carbon, how obtained by bacteria,
113.
Carbonic acid, action of, upon bac-
teria, 122.
Cell-membrane of bacteria, 35.
Cerebro-spinal meningitis, 284.
Ceri, investigations of, 326.
Characters, generic and specific, 60.
Charbon, 265.
Charbon symptomatiqne, 280.
Cheyne, experiments of, 398.
Chlorine, germicide value of, 221.
Chloroform, action of, upon bacte-
ria, 122, 220.
Chlorophyll, bacteria destitute of,
56.
Cholera, 285.
Cholera of fowls, 288.
Chromic acid, 221.
S, 72.
Cilia, described by Ehrenberg, 39.
extract from paper of Dallinger
and Drysdale describing, 41.
seen by various authors, 39.
Cladrothrix, 97.
Cl. dichotoma, 97.
Classification of Billroth, 23.
Bory de Saint- Vincent, 15.
Cohn, 65.
Davaine, 18.
Dujardin, 17.
Ehrenberg, 16.
Hoffman, 20.
0. F. Miiller, 14.
Nageli, 57.
Sachs, 57.
generic and specific charac-
ters, 59:
Claxton, experiments of, 370.
Coccobacteria septica of Billroth,
22.
Cold, effects of, upon the bacteria,
120.
Color of the bacteria, 31.
Colored bacteria, where found, 32.
Compressed air, action of, upon the
bacteria, 121.
Coze and Feltz, experiments of, 349.
Creosote, 222.
Culture flasks, 171, 177.
Culture-fluid of Cohn, 113.
Pasteur, 112.
Mayer, 113.
Culture-fluids, natural, 161.
artificial, 167.
sterilization of, 168.
Culture oven, 180.
Culture medium, solid, 158.
Cupric sulphate, 222.
DALLINGER and Drysdale, extract
from paper of, on " The Ex-
istence of Flagella in B.
Termo," 41.
Dnviiiix1, fl;issilir;ition of, 18.
Di -Illation of bacteria, 13.
Detmobftcttiift, 86.
Dimensions of the bacteria, 29.
INDEX.
495
Diphtheria, 257, 291.
Diphtheria of fowls, 297.
Dissemination of the bacteria, 103.
in air, 1 03.
in the human organism, 107.
in water, 106.
Distinction between animals and
vegetables, 53.
of bacteria from inorganic sub-
stances, 49.
Dujardin, classification of, 17.
EHRLICH'S method of staining tuber-
cle bacilli, 191.
Erysipelas, 286.
Ether, germicide value of, 222.
Eucalyptol, germicide value of, 222.
FAT granules in yellow-fever blood,
425.
resemblance of, to micrococci,
51.
Fehleisen, experiments of, 286.
Fermentation, acetic, 139.
ammoniacal, of urine, 142.
butyric, 145.
lactic, 144.
viscous, 146.
Fermentations, role of bacteiia in,
137.
Ferri chloridi tinct., 223.
Ferric sulphate, 222.
Fish, disease of, due to bacteria, 299.
Forms of the bacteria, 29.
Fungi, bacteria classed with, 56.
GERMICIDES, definition of, 209.
Gibbs' method of staining tubercle
•Hi, 192.
Glanders, 2
Gliabacterin, 45.
Gliacoccos, 4."..
Gonocoivus of Xeisser, 301.
Gonorrbrca, 301.
Grocers' Company, prize offered by,
413.
Grouping, different modes of, 43.
X, investigations of, 331.
Heat, germicide power of, 223.
Heterogenesis, 102.
Hoffman, memoir of, 20.
Hospital gangrene, probably due to
bacteria, 256.
Hydrochloric acid, 224.
Hydrophobia, 314.
INFECTIOUS pneumonia, 342.
Intermittent fever, 317.
experiments relating to, 323.
Iodine, germicide value of, 225.
KLEBS, erperiments of, relating to
intermittent fever, 319.
Koch, experiments of, relating to
tuberculosis, 387.
LAVERAN, investigations of, relating
to intermittent fever, 329.
Leprosy, 331.
Leptothrix, 90.
L. brevissima, 90.
L. croespitosa, 90.
L. parasitica, 90.
L. pusilla, 90.
L. radians, 90.
L. rigidula, 90.
L. spissa, 90.
Leptothrix form of grouping of the
bacteria, 43.
Lister's culture apparatus, 175.
MALIGNANT oedema, 336.
Measles, 340.
Mercuric bichloride, germicide value
of, 225.
Microbacteria, 65, 80.
Micrococcus, 72.
M. aurantiacus, 73.
M. bombycis, 76.
M. Candidas, 74.
M. chlorinus, 75.
M. crepusculum, 75.
M. cyaneus, 73.
M. diphtheriticus, 76, 292.
M. fulvus, 74.
496
INDEX.
Micrococcus luteus, 73.
M. of epidemic diarrhoea, 77.
M. of exanthematous typhus, 78.
M. of glanders, 78.
M. of intestinal typhus, 78.
M. of pyaemia of rabbits, 344.
M. of rugeola, 77.
M. of scarlatina, 77.
M. of septicaemia of rabbit, 359.
M. of stringy wine, 75.
M. of syphilis, 78.
.M. of the variola of animals, 77.
M. prodigiosus, 73.
M. septicus, 76.
M. ureae, 75.
M. vaccinse, 76, 412.
M. of variola, 441.
M. violaceus, 74.
Micrococci in measles, 341.
in pus, 304.
in gonorrhceal pus, 301.
in erysipelas, 286.
in wounds treated aseptically,
444.
in acute abscesses, 447.
Microsphaera vaccinae, 76.
Microsporon septicus, 76.
Microzyma bombycis, 76.
Milk as a culture fluid, 163.
Milk sickness, 339.
Miltzbrand, 265.
Miquel, experiments of, 104.
Monas crepusculum, 75.
M. gracilis, 79.
M. Okenii, 79.
M. prodigiosa, 73.
M. pulmonale, Klebs, 342.
M. tenno, 81.
M. vinosa, 79.
M. Warmingii, 79.
Movement, brownien, 33.
cause of, 34.
of two kinds, 32.
Miillor, 0. F., classification of, 14.
Multiplication, rapidity of, 125.
Mycoderma, form of, 45.
1C. acfti, 83, 140.
M. vini, 141.
Myconostoc, 96.
M. gregarium, 97.
NAGELI, classification of, 57.
Nitrification, role of bacteria in, 149.
Nitrous acid, 226.
Nitrogen, how obtained by the bac-
teria, 112.
Nutrition of the bacteria, 111.
OGSTON, experiments of, 449, 454.
Oil of mustard, 226.
Oil of turpentine, 226.
Ophidomonas sanguinea, 80.
Origin of the bacteria, 101.
Oscillaria malariae of Laverau, 329.
Osmic acid, 226.
Oxalic acid, 226.
Oxygen, r61e of, 115.
germicide power of, 227.
Ozone, action of, upon the bacteria,
121.
germicide power of, 227.
PALMELLA prodigiosa, 73.
Panum, experiments of, 262.
Pasteur, experiments relating to hy-
drophobia, 314.
Pathogenes, 75.
Pathogenic bacteria, development
of, 252.
Penicillium, in blood of yellow
fever, 426.
Pernicious fever, 325.
Petalobacteria, 46.
Petalococcos, 46.
Photographing bacteria, 194.
Picric acid, 227.
Pigmentary bacteria, 72.
Place of the bacteria in vegetable
series, 55.
Pleuro-pneumonia, 341.
Polymorphism, 133.
Position of the bacteria, 48.
Potash, germicide value of, 227.
Potassium arsrnite, 228.
chlorate, 228.
iodide, 228.
INDEX.
497
Potassium nitrate, 228.
permanganate, 228.
Protective inoculations in anthrax,
in septicaemia, 372.
modus operand i, Pasteur's ex-
planation of, 242.
Author's explanation, 246.
Protoplasm, currents in, 37.
granules in, 37.
of the bacteria, 36.
Pseudobacteria, 50.
Ptomaines, 257.
Pulverulent precipitate, consisting
of bacteria, 46.
Pure cultures, methods of obtaining:
Lister's method, 156.
Koch's method, 157.
Pus, bacteria in, 111, 307, 444.
Putrefaction, role of bacteria in, 148.
Pyaemia in rabbits, 343.
Pyrogallic acid, 229.
QUININE, germicide value of, 229,
326.
RECOGNITION of bacteria, 184.
Relapsing fever, 346.
inoculation experiments relat-
ing to, 347.
Reproduction of the bacteria, 123.
by fission, 123.
by spores, 126.
Respiration of the bacteria, 111.
Rhabdomonas rosea, 80.
Rosenberger, experiments of, 259.
SACCHAROMYCETES, 57.
Sachs, classification of, 57.
Salicylic acid, 229.
Saliva, micrococcus of, 359.
Sarcina, 96.
Scarlet fever, 349.
in animals, 350.
Schizomycetes, Nageli, 57.
Schizophytes, Cohn, 66.
Sepsin, 258.
Septic toxaemia, 259.
Septicaemia in mice, 351.
Septicaemia in rabbits, 355.
etiology of, 356.
pathology of, 360.
Soda, germicide value of, 230.
Sodium biborate, 231.
Sodium chloride, 231.
Sodium hyposulphate, 232.
Sodium salicylate, 232.
Sodium sulphite, 232.
Species, physiological, of Pasteur,
63.
value of, 61.
Spherobacteria, 71.
Spirillum, 94.
S. attenuatum, 96.
S. Rosenbergii, 96.
S. rufum, 94.
S. tenue, 94.
S. undula, 94.
S. violaceum, 96.
S. volutans, 94.
Spirobacteria, 91.
Spirochaete, 93.
S. gigantea, 93.
S. Obermeieri, 93.
S. plicatilis, 93.
Spirochsete Obermeieri, 347.
Spiromonas Cohnii, 80.
Sporangia, 130.
Spores, development of, 128.
germination of, 131.
Spores of B. anthracis, 270.
Spreading abscess in rabbits, 376.
Staining bacteria, 186.
Starch, in Bacillus amylobacter, 39.
Sterilization of culture-fluids, 168,
172.
Structure of the bacteria, 35.
Sulphur, contained in bacteria,
33.
Sulphuretted hydrogen, 234.
Sulphuric acid, 233.
Sulphurous acid, 233.
Swine plague, 378.
Symptomatic anthrax, 280.
Syphilis, 380.
Syphilitic organisms, 381.
498
INDEX.
TAXNIC acid, 234.
Temperature, action of, upon bac-
teria, 118.
Thermal death- point of bacteria, 119.
of B. anthracis, 270.
of M. of fowl cholera, 289.
of septic inicrococcus, 364.
Thermostat for gas, 181.
electro-magnetic, 183.
Thymol, 234.
Tommasi-Crudeli, experiments re-
lating to intermittent fever,
319, 325.
Torula form of bacteria, 43.
Tubercle bacillus, 386.
methods of staining, 190.
morphology of, 393.
Tubercles without bacilli, 390.
Tuberculosis, 384.
Typhoid bacilli of Klebs, 407.
of Eberth, 409.
Typhoid fever, 400.
lower animals not subject to,
403.
ULCERATIVE endocarditis, 411.
Urine as a culture-fluid, 164.
method of obtaining free from
bacteria, 165.
VARIOLA, 411.
Variola of pigeons, 413.
Venom of serpents, 261.
Vibrio, 92.
V. bacillus, 89.
V. lactic, 83.
V. lineola, 81.
V. prolifer, 94.
V. rugula, 92.
V. serpens, 93.
V. subtilis, 87.
V. syncyanus, 85.
V. synxanthus, 85.
V. tartaric right, 83.
V. tremulans, 81.
Vibrioniens, definition of, Ehren-
berg, 16.
WATER, examination of, 201.
Whooping cough, 415.
Wood, H. C., experiments of, 295.
YELLOW fever, 417.
blood of, 422, 108.
Yellow-fever commission, extracts
from report of, 421.
Yellow-fever germ of Carmona, 432.
of Freire, 439.
ZINC chloride, 234.
Zinc sulphate, 235.
Zoogloea form of grouping of the
bacteria, 44.
Zooglcea, genus established by
Cohn, 21.
Zymogenes, 75.
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