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SAUNDERS' QUESTION COMPENDS, NO. 20.



ESSENTIALS OF BACTERIOLOGY:



BEING A



CONCISE AND SYSTEMATIC INTRODUCTION TO THE
STUDY OF MICRO-ORGANISMS



FOR THE USE OF



STUDENTS AND PRACTITIONERS.



BY

M. V. BALL, M.D.,

LATE RESIDENT PHYSICIAN GERMAN HOSPITAL, PHILADELPHIA; ASSISTANT IN
MICROSCOPY, NIAGARA UNIVERSITY, BUFFALO, NEW YORK, ETC.



WITH SEVENTY-SEVEN ILLUSTRATIONS, SOME IN COLORS,



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oo

PREFACE.



FEELING the need of a Compendium on the subject of
this work, it has been our aim to produce a concise treatise
upon the Practical Bacteriology of to-day, chiefly for the
medical student, which he may use in his laboratory.

It is the result of experience gained in the Laboratory
of the Hygienical Institute, Berlin, under the guidance of
Koch and Frankel ; and of information gathered from the
original works of other German, as well as of French,
bacteriologists.

Theory and obsolete methods have been slightly touched
upon. The scope of the work, and want of space, forbade
adequate consideration of them. The exact measurements
of bacteria have not been given. The same bacterium
varies often much in size, owing to differences in the media,
staining, etc.

We have received special help from the following books,
which we recommend to students for further reference :

MAC: TraitS pratique de Bacteriologie.
FRANKEL: Grundriss der Bakterienkunde.
EISENBERG: Bakteriologische Diagnostik.
CROOKSCHANK, E. M.: Manual of Bacteriology.
GUNTHER: Einflihriug in das Studium der Bacteriologie, etc.
WOODHEAD AND HARE : Pathological Mycology.
SALMONSEN: Bacteriological Technique (English translation).

M. V. BALL.

BUFFALO, N. Y., October 1, 1891.
62 Delaware Avenue.

(v)



CONTENTS.



PART I.
GENERAL CONSIDERATIONS AND TECHNIQUE.

PAGE

Introduction . ix

CHAPTER I. CLASSIFICATION, STRUCTURE, AND RE-
PRODUCTION . . .... 17

" II. ORIGIN, LIFE, GROWTH, AND PROPERTIES 23

" III. METHODS OF EXAMINATION . . . 26

" IV. STAINING OF BACTERIA .... 30

" V. GENERAL METHOD OF STAINING SPECI-
MENS 34

" VI. SPECIAL METHODS OF STAINING . .37

" VII. METHODS OF CULTURE .... 39

" VIII. NUTRIENT MEDIA 44

" IX. SOLID TRANSPARENT MEDIA ... 47

" X. INOCULATION OF GELATINE AND AGAR . 53

" XI. GROWTH AND APPEARANCES OF COLONIES 58

" XII. CULTIVATION OF ANAEROBIC BACTERIA . 60

" XIII. MANNER IN WHICH BACTERIA ACT UPON

BODY 62

" XIV. IMMUNITY 66

XV. ANIMAL EXPERIMENTS .... 68

(vii)



viii CONTENTS.

PART II.
SPECIAL BACTERIOLOGY.

PAGE

CHAPTER I. NON-PATHOGENIC BACTERIA . . .72

Bacillus Prodigiosus 72

Indicus .72

Mesentericus Yulgatus 7.']

Megatherium 74

Ramosus 74

Bacterium Zopfi 75

Bacillus Subtilis 75

Spinosus 7(3

Some Bacteria in Milk 76

Bacillus Acidi Lactici 76

Butyricus 77

Amylobacter 77

Lactis Cyanogenus .... 78

Lactis Erythogenes .... 78

Some Noil-Pathogenic Bacteria of Water ... 79

Bacillus Violaceus ; Coeruleus ... 79

Fluorescent Bacteria 80

Phosphorescent Bacteria . . . .80

Crenothrix, Cladothrix, and Beggiatoa . 81

Bacterium Urese 82

Spirillum 83

Rubrum ; Concentricum 83

Sarcina 83

Lutea 83

Aurantica Flava, Rosea, and Alba ; Ventriculi . 84

CHAPTER II. PATHOGENIC BACTERIA . * . . .84

Bacteria Pathogenic for Man and other Animals . 84

Bacillus Anthracis 84

Tuberculosis 88

Lepra Bacillus 96

Syphilis Bacillus 97



CONTENTS. IX

PAGE

Bacteria

Bacillus of Glanders . . . . . .98

of Diphtheria 100

of Typhoid Fever' 101

Neapolitanus 104

CHAPTER III. PATHOGENIC BACTERIA CONTINUED . 105

Spirillum Choleras 105

Bacteria Similar to Spirillum Cholerse . . . 108

Finkler-Prior 108

Tyrogenum 109

Vibrio Metschnikoff 110

Bacteria of Pneumonia 110

Pneumo-bacilltis of Friedlander . . . .111

of Frankel . . . . .112

Bacillus of Khinoscleroma . . . . 115

Micrococcus Tetragenus 115

Capsule Bacillus . . . . . . . ' . 116

Micro-Organisms of Suppuration .... 116

Steptococcus Pyogenes 117

Staphylococcus Pyogenes Aureus .... 118

Micrococcus Pyogenes Albus, Citreus, Tenuis . 120

Cereus Albus, Flavus . . .120

Bacillus Pyocyaneus 120

Micrococcus Gonorrhoea .... . 121

Microbes Similar to Gonorrhoea .... 123

Bacillus of Tetanus 124

(Edematis Maligni 127

Spirillum of Relapsing Fever .... 129

Bacillus Malarise 130

Hsematozoa of Malaria 130

CHAPTER I V. BACTERIA PATHOGENIC FOR ANIMALS,

BUT NOT FOR MAN . . . . . 133

Bacillus of Symptomatic Anthrax .... 133

of Chicken Cholera . . ...... .134

Bacteria of Hemorrhagic Septicaemia, Swine Plagues,

Duck Cholera, etc 136



CONTENTS.

PAGE

Bacillus of Rabbit Septicaemia . . . . . 136

of Erysipelas of Swine 130

Murisepticus 138

Micrococcus of Mai de Pis 138

Bacillus Alvei 139

Micrococcus Ainylivorus 139

Bacterium Termo 139



APPENDIX.

Yeasts 141

Oidiums 142

Moulds 143

Actinomyces or Ray Fungus 144

Examination of Air 146

of Water 149

of Soil 152

CONCLUSION . . . . . 153



INTRODUCTION.



HISTORY. The microscope was invented about the latter
part of the sixteenth century ; and soon after, by its aid,
minute organisms were found -in decomposing substances.
Kircher, in 1646, suggested that diseases might be due to
similar organisms ; but the means at his disposal were in-
sufficient to enable him to prove his theories. Anthony
Van Leuwenhoeck, of Delft, Holland (1680 to 1723), so
improved the instrument that he was enabled thereby to
discover micro-organisms in vegetable infusion, saliva, fecal
matter, and scrapings from the teeth. He distinguished
several varieties, showed them to have the power of loco-
motion, and compared them in size with various grains of
definite measurement. It was a great service that this
"Dutch naturalist" rendered the world; and he can rightly
be called the " father of microscopy."

Various theories were then formulated by physicians to
connect the origin of different diseases with bacteria ; but no
proofs of the connection could be obtained. Andry, in 1701,
called bacteria worms. Miiller, of Copenhagen, in 1786, made
a classification composed of two main divisions monas and
vibrio ; and with the aid of the compound microscope was
better able to describe them. Ehrenberg, in 1833, with still
better instruments, divided bacteria into four orders: bac-
terium, vibrio, spirillum, and spirochsete. It was not until
1863 that any positive advance was made in connecting
bacteria with disease. Rayer and Davaine had in 1850

(xi)



Xll INTRODUCTION.

already found a rod-shaped bacterium in the blood of ani-
mals suffering from splenic fever (sang de rate), but they
attached no special significance to their discovery until
Pasteur made public his grand researches in regard to fer-
mentation and the role bacteria played in the economy.
Then Davaine resumed his studies, and in 1863 established
by experiments the bacterial nature of splenic fever or an-
thrax.

But the first complete study of a contagious affection was
made by Pasteur in 1869, in the diseases affecting silk-worms
pebrine and flacherie which he showed to be due to micro-
organisms.

Then Koch, in 1875, described more fully the anthrax
bacillus, gave a description of its spores and the properties
of the same, and was enabled to cultivate the germ on arti-
ficial media ; and, to complete the chain of evidence, Pas-
teur and his pupils supplied the last link by reproducing the
same disease in animals by artificial inoculation from pure
cultures. The study of the bacterial nature of anthrax has
been the basis of our knowledge of all contagious maladies,
and most advances have been made first with the bacterium
of that disease.

Since then bacteriology has grown to huge proportions
become a science of itself and thousands of earnest workers
are adding yearly solid blocks of fact to the structure, which
structure it will be our aim to briefly describe in the pages
which are to follow,



ESSENTIALS OF BACTERIOLOGY.

*

PART I.
GENERAL CONSIDERATIONS.



CHAPTER I.

BACTERIA.

BACTERIA (daxtypiov, little staff) is the name given to a group
of the lowest form of plants, very closely following the algae.
They were called Fission- Fungi or Schizomycetes (o^t^w, to cleave,
/uor^j, fungus), because it was thought that, as the Fungi, they
lived without the chlorophyll. The word fission was supplied
to distinguish them from moulds and yeasts, it denoting the
manner of reproduction. Since several bacteria have been
found to possess chlorophyll, and as a great many increase in
other ways than by simple fission the name of Schizomycetes
can no longer be applied, though the word Bacteria leaves much
to be desired.

Classification. Ferdinand Cohn, in the middle of the present
century, was the first to demonstrate bacteria to be of vegetable
origin, they being placed previous to that among the infusoria.
He arranged them according to their form under four divisions.

Cohn's System. I. Spherobacteria (globules).

II. Microbacteria (short rods). \ ^
III. Desmobacteria (long rods). /
IY. Spirobacteria (spirals).
As expressed at the present time, Micrococcus, Bacillus, and
Spirillum. This classification is very superficial, but because a
better one has not been found it is most in use to-day.

2 (17)




18 ESSENTIALS OF BACTERIOLOGY.

De Bary's System. De Bary divides bacteria into two groups,
those arising from or giving rise to endospores and those devel-
oped from arthrospores. This division has a more scientific
value than the first.

FIG. 1.



Jo^Tv ^

Micrococcus. Spirillum. Bacillus.

Structure. Bacteria are cells ; they appear as round or cylin-
drical of an average diameter or transverse section of 0.001 mm.
(=1 micromillimeter), written 1 /*. The cell, as other plant-
cells, is composed of a membranous cell-wall and cell-contents ;
"cell-nuclei" have not yet been observed, but the latest re-
searches point to their presence.

Cell- Wall. The cell-wall is composed of plant cellulose, which
can be demonstrated in some cases by the tests for cellulose.
The membrane is firm and can be brought plainly into view by
the action of iodine upon the cell-contents which contracts them.

Cell-Contents, The contents of the cell consist mainly of
protoplasm, usually homogeneous, but in some varieties, finely
granular, or holding pigment, chlorophyll, granulose, and sul-
phur in its structure.

It is composed chiefly of myco^yrotcin.

Gelatinous Membrane. The outer layer of the cell-membrane
can absorb water and become gelatinoid, forming either a little
envelope or capsule around the bacterium or preventing the
separation of the newly-branched germs, forming chains and
bunches, as strepto- and staphylo-cocci. Long filaments are also
formed.

Zoogloea. "When this gelatinous membrane is very thick, irre-
gular masses of bacteria will be formed, the whole growth being
in one jelly-like lump. This is termed a zoogl<wv (ww, animal,

. .jlue).
Locomotion, Many bacteria possess the faculty of self-move-



BACTERIA. 19

ment, carrying themselves in all manner of ways across the
microscopic field, some very quickly, others leisurely.

Vibratory Movements. Some bacteria vibrate in themselves,
appearing to -move, but they do riot change their place ; these
movements are denoted as molecular or " Brownian."

FIG. 2.




Zooglcea.

Flagella. Little threads or lashes are found attached to many
of the motile bacteria, either at the poles or along the sides,
sometimes only one, and on some several, forming a tuft.

These flagella are in constant motion and can probably be
considered as the organs of locomotion ; they have not yet been
discovered upon all the motile bacteria, owing no doubt to our
imperfect methods of observation. They can be stained and
have been photographed. See Fig. 3.

Reproduction. Bacteria multiply either through simple divi-
sion or through fructification by means of small round or oval
bodies called spores from spora-seed. In the first case, division,
the cell elongates, and at one portion, usually the middle, the
cell-wall indents itself gradually, forming a septum and dividing
the cell into two equal parts, just as occurs in the higher plant
and animal cells. See Fig. 4.



20



ESSENTIALS OF BACTERIOLOGY.



FIG. 3.




Flagella.

Successive divisions take place, the new members either exist-
ing as separate cells or forming part of a community or group.



FJG. 4.



/-;



1 Z 3

Division of a Micrococcus. (After Mac6.)



*._.. .-*




/






^



Division of a Bacillus. (After Mace".)

Spore Formations. Two forms of sporulation, Endosporous
and Artlirosporous. A small granule develops in the protoplasm



BACTERIA.



21



of a bacterium, this increases in size, or several little granules
coalesce to form an elongated, highly refractive, clearly defined
object, rapidly attaining its real size, and this is the spore. The
remainder of the cell-contents has now disappeared, leaving
the spore in a dark, very resistant, membrane or capsule, and
beyond this the weak cell-wall. The cell-wall dissolves gradu-
ally or stretches and allows the spore to be set free.

Each bacterium gives rise to but one spore. It may be at
either end or in the middle (Fig. 5). Some rods take on a pecu-
liar shape at the site of the spore, making the rod look like a
drum-stick or spindle, clostridium (Fig. 6).



FIG. 5.



FIG. 6.





Sporulation. After De Bary.



Clostridium.



Spore Contents. What the real contents of spores are is not
known. In the mother cell at the site of the spore little gran-
ules have been found which stain differently from the rest of
the cell, and these are supposed to be the beginnings, the sporo-
genic bodies. The most important part of the spore is its cap-
sule; to this it owes its resisting properties. It consists of two
separate layers, a thin membrane around the cell, and a firm
outer gelatinous envelope.

Germination. When brought into favorable conditions, the
spore begins to lose its shining appearance, the outer firm mem-



22 ESSENTIALS OF BACTERIOLOGY.

brane begiris to swell, and it now assumes the shape and size
of the cell from which it sprang, the capsule having burst, so as
to allow the young bacillus to be set free.

Requisites for Spore Formation, It was formerly thought that
when the substratum could no longer maintain it, or had become
infiltrated with detrimental products, the bacterium-cell pro-
duced spores, or rather turned itself into a spore to escape anni-
hilation ; but we know now that only when the conditions are
the most favorable to the well-being of the cell, does it produce
fruit, just as with every other type of plant or animal life, a cer-
tain amount of oxygen and heat being necessary for good spore
formation.

Asporogenic Bacteria. Bacteria can be so damaged that they
will remain sterile, not produce any spores. This condition can
be temporary only, or permanent.

Arthrosporous. All the above remarks relate to Endospores,
spores that arise within the cells.

In the other group called Arthrospores, individual members
of a colony or aggregation leave the same and become the origi-
nators of new colonies, thus assuming the character of spores.

The Micrococci furnish examples of this form.

Some authorities have denied the existence of the arthro-
sporous formation.

Resistance of Spores. Because of the very tenacious envelope,
the spore is not easily influenced by external measures. It is
said to be the most resisting object of the organic world.

Chemical and physical agents that easily destroy other life
have very little effect upon it.

Many spores require a temperature of 140 C. dry heat for
several hours to destroy them. The spores of a variety of potato-
bacillus (bacillus mesentericus) can withstand the application of
steam at 100 C. for four hours.



ORIGIN OF BACTERIA. 23

CHAPTER II.

ORIGIN OF BACTERIA AND THEIR DISTRIBUTION.

As Pasteur has shown, all bacteria develop from pre-existing
bacteria, or the spores of the same. They cannot, do not arise
de novo.

Their wide and almost universal diffusion is due to the minute-
ness of the cells and the few requirements for their existence.

Very few places are free from germs ; the air on the high seas,
and on the mountain tops, is said to be free from bacteria,
but it is questionable.

One kind of bacterium will not produce another kind.

A bacillus does not arise from a micrococcus or the typhoid
fever bacillus produce the bacillus of tetanus.

This subject has been long and well discussed, and it would
take many pages to state the " pros" and " cons," therefore, this
positive statement is made, it being the position now held by the
principal authorities.

Saprophytes and Parasites. (Saprophytes, $a?tpo?, putrid, $vtov,
plant. Parasites, rtapa, aside of 6iro$, food.) Those bacteria
which live on the dead remains of organic life are known as
Saprophytic Bacteria, and those which choose the living bodies
of their fellow-creatures for their habitat are called Parasitic
Bacteria. Some, however, develop equally well as Saprophytes
and Parasites. They are called Facultative Parasites.

Conditions of Life and Growth of Bacteria. Influence of Tem-
perature. In general, a temperature ranging from 10 C. to 40
C. is necessary to their life and growth.

Saprophytes take the lower temperatures ; Parasites, the tem-
perature more approaching the animal heat of the warm-blooded.
Some forms require a nearly constant heat, growing within very
small limits, as the Bacillus of Tuberculosis.

Some forms can be arrested in their development by a warmer
or colder temperature, and then restored to activity by a return
to the natural heat.



24: ESSENTIALS OF BACTERIOLOGY.

A few varieties exist only at freezing point of water ; and
others again that will not live under a temperature of 00 C.

For the majority of Bacteria a temperature of 00 C. is de-
structive ; and several times freezing and thawing very fatal.

Influence of Oxygen. Two varieties of bacteria in relation to
oxygen.

The one cerofo'c, growing in air ; the other anccrobic, living
without air.

Obligate azrobins, those which exist only when oxygen is present.

Facultative a>robins, those that live best when oxygen is present,
but can live without it.

Obliijate or true anccrobins, those which cannot exist where
oxygen is.

facultative ancerobins, those which exist better where there is
no oxygen, but can live in its presence.

Some derive the oxygen which they require out of their nutri-
ment, so that a bacterium may be terobic and yet not require
the presence of free oxygen.

JErobins may consume the free oxygen of a region and thus
allow the anrerobius to develop. By improved methods of cul-
ture many varieties of ancerobins have been discovered.

Influence of Light. Sunlight is very destructive to bacteria.
A few hours' exposure to the sun has been fatal to anthrax
bacilli, and the cultures of bacillus tuberculosis have been killed
by a few days' standing in daylight.

Effects of Electricity. Electricity arrests growth.

Vital Actions of Microbes. Bacteria feeding upon organic com-
pounds produce chemical changes in them, not only by the with-
drawal of certain elements, but also by the excretion of these
elements changed by digestion. Sometimes such changes are
destructive to themselves, as when lactic and butyric acids are
formed in the media.

Oxidation and reducivm are carried on by some bacteria. Am-
monia, hydrogen sulphide, and trimethylamin are a few of the
chemical products produced by bacteria.

Ptomaines, Brieger found a number of complex alkaloids,
closely resembling those found in ordinary plants, and which



ORIGIN OF BACTERIA. 25

he named ptomaines, from rt^^a (corpse), because obtained
from putrefying objects.

Fermentation, This form of "splitting up" fermentation,
as it is called is due to the direct action of vegetable organisms.
Many bacteria have the power of ferments.

Putrefaction. When fermentation is accompanied by devel-
opment of offensive gases, a decomposition occurs, which is
called putrefaction, and this, in organic substances, is due
entirely to bacteria.

Liquefaction of Solid Gelatine. Some varieties of bacteria


1 3 4 5 6 7 8 9 10 11 12

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