EXPERIMENTS ON THE ACTION OF BAC- 
TERIA ON OPERATIONS OF THE EYE 
BY 
H. KNAPP 
[Reprinted from the Archives of Ophthai.moi.ogy, Vol. xv., No. i, 1886] EXPERIMENTS ON THE ACTION OF BACTERIA 
ON OPERATIONS OF THE EYE. 
By H. KNAPP. 
AT the end of a systematic bacteriological course in 
Koch’s laboratory, in Berlin, I received pure cul- 
tures of pyogenous microbes — namely, staphylococcus 
pyogenes aureus, albus, and citreus, bacillus pyogenes 
fcetidus, and the micrococcus of osteomyelitis. With these 
I made (first at the Hygienic Institute, afterwards in the 
Anatomy Building, where Prof. Waldeyer and Dr. Hans 
Virchow kindly put sufficient room at my disposal, and 
obliged me besides by manifold instruction, although chiefly 
in another field) a series of experiments on rabbits, in order 
to ascertain how a pure wound differed in its healing 
process from an infected wound. The experiments were 
conducted in this way: first, I made a pure operation on 
one eye, using, however, no chemical agents but operating 
on a clean, healthy eye with clean hands and instruments— 
i.e., aseptically, not antiseptically, and, after the operation, 
leaving the eye alone without a bandage. The other eye 
was operated upon in the same way, consequently subjected 
exactly to the same traumatism, but inoculated one way or 
other, with a pure-culture of bacteria. In so doing, I imi- 
tated the chief operations that are practised on the human 
subject, and desire to premise the remark that all eyes 
operated on aseptically recovered, whereas almost all of 
those infected with the above-mentioned microbes were 
lost by suppuration, only those getting well in which the 
operations had been superficial and limited. Further, I 
inoculated several eyes with a fermentation-fungus, that of 
Reprinted from the Archives of Ophthalmology, Vol. xv., No. i, 1886. 25 
Action of Bacteria on Operations of the Eye. 
pink yeast. This microbe produced transient parenchyma- 
tous inflammation, but no suppuration. The experiments 
thus furnish illustrations of the action both of pyogenic and 
non-pyogenic fungi. I will first describe the different 
operations and their results, and afterward discuss them 
comprehensively in the light of the literature pertaining to 
the subject. 
a.—EXPERIMENTS WITH A NON-PYOGENIC FUNGUS. 
Experiment I.—Nov. 24, 1885.—I contaminated an incision 
through the cornea of a rabbit with a pure culture of the white 
pyogenic staphylococcus. On the next day I found the pro- 
nounced picture of purulent panophthalmitis. The profuse secre- 
tion, containing micrococci, was used for several plate-cuitures 
which developed well and, inoculated on other rabbits, again pro- 
duced purulent inflammation. Of the plate cultures I took test- 
tube cultures, which on agar reproduced the staphylococcus in a 
brighter white color than the original which I had received on 
gelatine. An agar puncture-culture, taken from the plate after 
seven days, developed on the surface into a most beautifully 
pink, inodorous little disc. As it differed from the other cultures 
only in color, I considered it to be a variety of staphylococcus 
pyogenes and used it in the following experiment. 
Dec. 9, 18S5.—After instillations of cocaine (which was used in 
all experiments), I made with the Graefe cataract-knife an incision 
through the upper part of the cornea and iris. The iris protruded. 
The wire speculum was removed, and the eye left so. 
The right eye was operated in the same way, but a small 
quantity of the pink fungus was put into the wound with a loop 
of platinum wire, previously brought to a glow. This eye, like 
the other, was left without a bandage. 
Next morning both eyes looked materially alike. There was no 
secretion in the left; a small flake of mucus lay on the wound in 
the right. No injection ; the upper part of both corneae somewhat 
diffusely gray ; centre and lower part of each was clear. The iris 
filled both wounds without irritation ; the pupils were black, and 
the irides within the eye normal. Both eyes recovered, with a 
leucoma along the section, in ten days. 
Two puncture cultures in peptonized meat-water gelatine 
were tak;en from the flake of mucus on the wound of the H. Knapp. 
right eye. They developed feebly into several white points. 
The first test-tube contained a pink coat on the surface and 
two slightly yellowish points in the interior of the gelatine. 
Both, examined later under the microscope, proved to be 
pure accumulations of yeast-cells, which had not yet lique- 
fied the gelatine in the least in nineteen days. Some 
puncture-cultures, taken from the depth of the wound canal, 
liquefied the gelatine, and under the microscope were dis- 
covered to consist exclusively of cocci. 
Experiment II.—On the same day a guinea-pig was operated 
on in the same manner. The next day no secretion, on the left 
eye ; some mucus on the right ; both wounds slightly gaping; the 
adjacent cornea diffusely gray, more on the right (infected side) 
than on the left. The wounds closed in five days ; the corneal 
opacity of the left eye disappeared completely ; that of the right 
left a simple speck in the upper part. 
Two test-tube cultures, taken from the mucous secretion of the 
right eye the day after the operation, the one in gelatine, the other 
on agar, developed into a white thread in the gelatine, and a white, 
somewhat waxy-looking coat on the agar. The gelatine was lique- 
fied and covered with a dirty white, offensive coat, which in one 
place looked reddish-yellow and consisted of irregular debris of 
cells. Microscopically only very small cocci were found, about 
half of which lay together in pairs. 
Some fresh cultures in agar and gelatine were taken from 
the pink fungus of the puncture in experiment I. They 
developed quickly and beautifully in the pink color of the 
original. The gelatine was not liquefied, nor, of course, the 
agar. 
The white coat on the peptonized meat-water agar was a 
mixture of cocci and short bacilli. 
Experiment III.—Dec. 16, ’85.—Middle-sized rabbit. On the 
left side extraction of the lens with extensive prolapse of vitreous, 
brought about intentionally ; on the right side extraction of the 
lens with section through the iris, without loss of vitreous. A 
small quantity of the pure culture of the pink fungus on agar was 
introduced through the wound into the anterior chamber of the 
right eye. The rabbit drew the nictitating membrane over the 
cornea causing the corneal flap, raised by the prolapse of vitreous Action of Bacteria on Operations of the Eye. 
in the left eye, to apply to the posterior lip of the wound in about 
an hour. 
Next day the wound of the left eye was free from irritation and 
almost closed. The wound of the right eye was gaping and cov- 
ered with some mucus. The upper part of the cornea diffusely 
gray, not white. 
Both eyes recovered about equally well in two weeks. No irri- 
tation, no ciliary injection,—two test-tube cultures of the limpid 
liquid in the anterior chamber of the right eye did not develop. 
This eye also remaining free from suppuration, the convic- 
tion forced itself upon me that the pink fungus must differ 
from the other kinds and be benign. On examination, un- 
der the microscope, I found at the first glance that it was 
no schizomyces at all but a fermentation-fungus (Sprosspilz, 
sprouting fungus), according to its aspect and all its re- 
actions the common pink torula, the fungus of the pink 
yeast, which in Koch’s laboratory I had cultivated and ex- 
amined often enough. Nevertheless, I inoculated with a 
pure culture of it 
Experiment IV.—On Dec. 17th.—Another eye after extraction 
of the lens. To make a test case of this experiment I stroked the 
whole wound with the fungus and introduced a quantity about the 
size of a pin-head into the anterior chamber. The next day I 
found the wound closed, clean, covered with some mucus which 
consisted of phlegm corpuscles and a few yeast cells. Some mucus 
on the edges of the lids. No swelling of the conjunctiva. Cornea 
clear. No blood in the anterior chamber. No suppuration. The 
eye recovered with formation of a secondary cataract, posterior 
synechise, and bulging iris. 
These four experiments show distinctly that the fungus 
of the pink yeast is not pyogenic. All the wounds in- 
fected with it healed in the same way as those which re- 
sulted from clean operations done on the fellow eye, with 
this distinction only that the harmless foreign body was 
cast off with the formation of a small quantity of mucus. 
When I spoke to Dr. George Frank, one of the assistants in 
Koch’s laboratory, of the results of these experiments, he 
told me that the pink torula was abundantly present in the H. Knapp. 
28 
air of the laboratories in Berlin. Although this widespread 
fungus entered as a contamination into one of my cultures, 
I was very much interested by the course of the inoculations 
I made with it, for it furnished a clear demonstration of the 
fact that a microbe resembling pyogenic schizomycetes 
both macroscopically and in cultures (with the exception 
of not liquefying nutrient gelatine) may totally differ from 
it in its action on living animal tissues. 
b.—EXPERIMENTS WITH PYOGENIC FUNGI. 
Experiment V.—Discision. Injection of osteomyelitis 
fungus into the anterior chamber. Panophthalmitis. 
On Dec. 18, ’85, I made with a Graefe cataract-knife a discision 
of the lens in both eyes of a middle-sized rabbit. With a Koch’s 
syringe I injected one drop of a fresh emulsion of the orange 
fungus of osteomyelitis, cultivated on agar, into the anterior cham- 
ber of the right eye, letting the animal afterward without bandage 
take care of itself. 
Dec. 19th.—Left, opacity of the lens without any irritation ; 
Right, profuse purulent secretion ; cornea white, anterior cham- 
ber full of pus. 
Dec. 21 st.—Left, no irritation; Right, purulent secretion; an- 
terior chamber filled with pus ; cornea ulcerous. 
Dec. 22d.—Eyes in the same condition. The animal is emaci- 
ated ; its hair shaggy, and it suffers from yellow diarrhoeic dis- 
charges. Innumerable small cocci are found on microscopic ex- 
amination of dried and stained cover-glass specimens, taken with 
a previously heated gelatine wire from the pus in the anterior 
chamber. 
Dec. 23d,—Left eye free from irritation ; the right cornea par- 
tially destroyed ; purulent panophthalmitis. The animal looks 
wretched, and dies in the night. 
Dec. 2\th, Autopsy.—The skull was opened with bone 
scissors. The brain was normal. The optic tracts were sev- 
ered behind the chiasm. With a small pair of bone-forceps 
the osseous plates covering the optic nerves were removed 
and the optic nerves of both eyes carefully laid bare. 
Neither they nor the chiasm showed any thing abnormal; 
the internal organs were found healthy with the exception 29 
Action of Bacteria on Operations of the Eye. 
of the liver which contained numerous small yellowish, 
dense patches. Gelatine and agar cultures were taken 
from the interior of the right eye, the chiasm, and the 
optic nerves close behind the eye. They all developed 
well. Dry-cover specimens, taken from the same places, 
and from the blood and the interior of the left eye, were 
stained with aniline colors, but cocci were found only in the 
pus which filled the interior of the right eye. They were 
present in great quantities in the protoplasm of the pus cor- 
puscles, or scattered also in the adjoining free space, or lying 
in large colonies on a collection of pus cells. They were ex- 
actly like the small cocci injected into the anterior chamber. 
Here and there they were arranged in small chains. Beside 
these, a sparing quantity of equally or more darkly-stained, 
larger (about twice the size of the smaller) granules were 
found single, in small clusters or chains. They have been 
described as larger cocci, but may be spores of mould. The 
cultures from the chiasm and the optic nerves had grown 
but little and were inodorous. Those from the right optic 
nerve and the chiasm showed under the microscope an innu- 
merable quantity of short bacilli with some micrococci inter- 
spersed. Surprised at this condition I prepared several speci- 
mens from different places of the cultures and examined 
them carefully: they appeared like short bacilli, not as 
diplococci. The culture, taken from the left optic nerve 
near the globe, proved to be pure ordinary cocci, many of 
them arranged in short chains. A culture taken from the 
discinded lens of the left eye had developed, and consisted 
of cocci. 
Experiment VI.—Discision. Injection of the fungus of 
osteomyelitis into the anterior chamber. Panophthalmitis. 
Dec. i%th.—I made, in a like rabbit, a similar simple discision of 
the lens in both eyes, and injected into the anterior chamber of 
the right a drop of an emulsion of osteomyelitis fungus from a 
test-tube culture which I had taken from the anterior chamber of 
a rabbit previously inoculated with the same fungus. 
Dec. xqth.—L, no irritation ; lens opaque. R, purulent secre- 
tion. Anterior chamber half filled with pus. H. Knapp. 
30 
Dec. 20th.—L, no irritation. R, intense suppuration ; Cornea 
sloughing ; anterior chamber filled with pus. 
Dec. 22d.—Pus from the anterior chamber contains groups of 
ordinary cocci in the protoplasm of the cells. 
Dec. 26th.—R, still copious discharge ; cornea totally destroyed; 
iris lying bare. L, lens less opaque ; no irritation. 
Dec. 29th.—R eye one mass of pus. 
Dec. 31st.—R, cornea and iris having disappeared, a white gran- 
ular substance protrudes from the depth. The lean but lively 
animal, the left pupil of which is almost completely clear, is put 
to death by chloroform. 
AUTOPSY.—Opening of the skull as in the preceding case. 
Brain and inner organs normal, excepting the liver, which 
contained a number of gray dense patches free from cocci. 
The right eyeball is small, its sclerotic white, whereas that 
of the other eye is blackish. The right optic nerve is slighty 
yellowish, otherwise not different from the (normal) left. 
Chiasm normal. The left eye, apart from the discision scar, 
is perfectly healthy. I desire to state particularly that 
nothing abnormal can be detected in the fundus oculi either 
with the naked eye or with a magnifier. 
Dry-cover specimens and cultures were taken from the 
interior of the right eye, both optic nerves, the medulla 
oblongata, the heart-blood, the juice of the kidneys, and the 
disseminated patches in the liver. The inflammatory changes 
in the kidneys, which F. Krause describes in his experi- 
ments, were absent. The right optic disc and adjacent 
parts were swollen ; the specimens taken from these parts 
contained numerous groups of small, apparently shrunken 
cocci, regularly developed only here and there. The speci- 
mens from the optic nerves and chiasm contained no unmis- 
takable cocci. 
In six days, at the temperature of a heated room, only 
three of the cultures developed—namely, those from the 
vitreous, optic nerve and optic tract of the right eye. The 
first two were pure cocci, but that from the right optic 
tract, and perhaps the adjacent brain substance, into which 
the inoculating-needle may have dipped, showed short bacilli 
exclusively. One colony only of this culture, about the Action of Bacteria on Operations of the Eye. 
size of a millet seed, in the middle of the needle-track, had 
developed, whereas a goodly number of dots lined the track 
from the optic-nerve culture, and the culture from the vitre- 
ous had grown luxuriantly. 
Experiment VII.—Section through cornea, iris, and lens. 
Painting of the wound with staphylococcus pyogenes albus. 
Panophthalmitis. 
On Sept. 24th, in the bacteriological laboratory of Berlin, I made 
with a Graefe knife a section, about 9 mm 'Aong, through the upper 
part of the cornea, iris, and lens of both eyes of a full-grown rab- 
bit. The iris prolapsed. A small quantity of a pure culture of 
the white pyogenic staphylococcus, taken directly from the test- 
tube with a sterilized platina wire loop, was spread over the 
wound of the right eye. 
Dec. 25th.—No secretion, no irritation in the left eye. The 
protruding iris, plugging the wound completely, is covered by a 
trace of mucus. The upper part of the cornea is diffusely gray, 
clearing toward the centre. The anterior chamber is reestablished. 
The lower half of the cornea, the aqueous humor, iris, and pupil 
are clear. To finish the description of this eye without inter- 
ruption I will state that the prolapse of iris diminished from day 
to day, and finally disappeared without the formation of a staphy- 
loma ; the cornea was clear except at the site of the wound, and 
the centre of the lens remained transparent. 
In the right eye profuse purulent secretion had developed. 
The conjunctiva was red and moderately swollen. The cornea 
was white in the vicinity of the wound, the iris discolored and 
swollen. 
Dec. 26th.—R eye swollen ; copious purulent discharge ; the 
wound closed ; the upper part of the cornea white ; the anterior 
chamber filled with pus ; in short, the picture of suppurative pan- 
ophthalmitis in its typical aspect after extraction of cataract. 
Dec. 27th.—Anterior chamber filled with pus ; cornea white, in- 
filtrated all around. 
Paracentesis liberated flaky pus, in which I detected no 
cocci with the microscope, but four needle and three plate 
cultures taken from it developed pure staphylococcus albus 
and aureus mixed. They had macroscopically and micro- 
scopically the same appearance as the original culture, and H. Knapp. 
32 
on inoculation manifested the same degree of virulence. 
Two days later I enucleated the eye and placed it in alco- 
hol. When hardened it was examined with the microscope. 
Microtome sections discovered cocci in the substance of the 
cornea but not in the protruding iris. The whole interior 
was filled with a chalky-white, somewhat granular mass, in 
which cocci were not detected with certainty. 
Experiment VIII.— Wound contaminated with virulent 
pus. No suppuration. 
Nov. 25th.—A section extending to the ciliary region was made 
through the upper part of both corneae of a guinea-pig, and pus 
from the conjunctival sac of the rabbit described in the preceding 
case was stroked over the wound in the right eye by means of a 
platina wire loop. 
Nov. 26th.—Both corneae around the wound diffused and 
opaque, the right somewhat more than the left. No secretion. 
Both wounds closed ; the corneae cleared up ; the left was quite 
clear in nine, the right in fourteen, days. 
EXPERIMENT IX.—Pyogenic fungi put into the conjuncti- 
val sac, then incision made through cornea and iris. No sup- 
puration. 
Nov. 26th.—I put, by means of a wire loop, several drops of a 
liquefying, very luxuriant culture of staphylococcus pyogenes 
albus and aureus mixed, from a plate, into the right conjunctival 
sac of a rabbit. Ten minutes later I thrust a cataract-knife 
through the cornea, iris, and lens of this eye, after having just 
before made the same operation on the left, not infected, eye. 
Nov. 27th.—The wound of the right eye healed so as to leave 
scarcely a trace of the injury. In the left a prolapse of iris, clean, 
disappearing gradually without irritation in two weeks ; cornea 
and pupil clear. 
Experiment X.—Corneal section with infected knife. Pan- 
ophthalmitis. 
Nov. 26th.—On the left side, section with a Graefe knife through 
cornea, iris, and lens ; on the right, the same operation after the 
knife had previously been dipped into the liquefied gelatine on a 
plate of a pure culture of staph, pyog. aur. 
Nov. 27th.—L, prolapse of iris ; no secretion ; no irritation 33 
Action of Bacteria on Operations of the Eye. 
During the following ten days the wound healed in the ordinary 
way, without irritation, leaving a partial staphyloma. On the 
right side the lids were swollen, closed by dried, purulent secre- 
tion, which, on forcible opening of the lids, ran out copiously. 
Chemosis. Upper segment of cornea white, infiltrated with pus. 
Pus in the anterior chamber. 
Nov. 30th.—R, suppuration increased. 
Dry-cover specimens of the secretion discovered no micro- 
organisms with certainty, but needle cultures taken from the 
secretion developed vigorously as staphylococcus pyogenes 
aureus. 
Dec. $th.—The inflammatory symptoms gradually subsided, the 
wound contracted. 
On Dec. 10th only the upper part of the cornea was yellow, but 
covered with epithelium. 
I made an incision into the yellow, infiltrated portion of 
the cornea, and used the tissue juice for dry-cover speci- 
mens and test-tube cultures. The former discovered no 
microbes and the latter did not develop, the microbes evi- 
dently having all been dead. 
Jan. 21, 1886.—The yellow infiltration disappeared completely 
and the inflammation disappeared, leaving a slightly prominent 
corneal staphyloma. 
Experiment XI.—Corneal section, contaminated with 
staphyloc. pyog. aur. Panophthalmitis. 
Dec. \th—Puncture of the right cornea of a rabbit with a broad 
needle, enlarged with scissors. Particles of a pure culture of 
staph, pyog. aur. on agar were put with a wire into the anterior 
chamber, near the wound, and the wire was passed once over the 
iris protruding in the wound. L, the same operation with the 
same instruments, previously brought to a glow in a gas flame. 
No inoculation. 
L, prolapse of iris, but no inflammation. The recovery took 
place in the usual way. 
R, profuse suppuration. Cornea white. 
Dec. qth.—The whole right cornea white. Suppuration copious. 
Dec. 12th.—Upper and central parts of cornea white, lower 
gray. Termination, total opacity of cornea. H. Knapp. 
34 
On the second day, cultures were taken from the pus in 
the anterior chamber. They developed on agar as staphyloc. 
pyog. aur. pure, in gelatine as st. pyog. aur., and alb. mixed. 
Cultures from the juice of the inspissated infiltration of the 
cornea did not develop. 
Experiment XII.—Section through cornea and iris, con- 
taminated with staphyloc. pyog. alb. Panophthalmitis. 
With a pure culture, derived from the pus in the anterior chamber 
of the rabbit used in experiment VII., the right eye of a rabbit was 
infected by means of a wire loop moistened with the culture (albus) 
and passed over a simple incision through the cornea and iris. In 
the left eye the same procedure with a wire loop previously heated 
to a glow. This eye recovered in the usual way without irritation. 
The other presented next day the well-marked picture of primary 
suppuration, developing into panophthalmitis. 
On the second day, cultures were taken from the pus of 
the wound. They developed as a mixture of staphyl. pyog. 
albus, aureus, and citreus. On agar two thirds were aureus, 
one third albus. In dry-cover specimens the cocci were 
found abundantly. On the sixth day I killed the animal, 
found everything normal, excepting the eyes; in particu- 
lar, the optic nerves, the chiasm, and the brain were without 
macroscopic changes. 
Experiments XIII. and XIV.—Extraction. Contami- 
nation with bacillus pyogenes foetidus and staphyloc. pyog. 
citreus. Panophthalmitis. Vascular parenchymatous keratitis. 
On the 15th of Dec. I made an extraction on both eyes of two 
rabbits, and contaminated the wound of the right eye of one rab- 
bit with a pure culture of bacillus pyogenes foetidus, that of the 
other with staplyloc. pyog. citreus, both discovered by Passet. In 
order to render the difference between mere traumatism and in- 
fection as conspicuous as possible, I made the operations on the 
left eye in both rabbits most extensive. When the lens was re- 
moved, I passed a wire previously brought to a glow, repeatedly over 
the ciliary processes until a large prolapse of vitreous had occurred 
and the wound gaped widely. The rabbits left alone drew the 
nictitating membrane repeatedly over the eye, and in about an 
hour the prolapse of vitreous had been brushed away. They kept 35 
Action of Bacteria on Operations of the Eye. 
their eyes open, moving the lids and the nictitating membrane 
from time to time. 
These two, quite coarse operations, were recovered from with- 
out a trace of suppuration, with very slight injection, and without 
secretion. 
The two right eyes, on which the extraction had been performed 
continuously and without accident, presented profuse suppuration 
of the wound ; white cornea and gray iris on the following day. 
Subsequently the eyeball swelled, the anterior chamber was filled 
with pus and the secretion was profuse. The upper part of the 
cornea gradually sloughed away, the wound filled with inspissated 
pus and retracted, while the remainder of the cornea became dif- 
fusely opaque and covered from the edge with a dense network 
of blood-vessels (vascular parenchymatous keratitis, Jan. 2, ’86). 
The secretion of the wound examined by means of culti- 
vation and dry-cover glass specimens contained many bac- 
teria. The cultures of fcetidus were short bacilli, did not 
liquefy the gelatine, had a blue tinge on the surface, and a 
bad odor. The cultures of citreus were cocci, they liquefied 
the gelatine, and were partially white, partially more or less 
orange, without reproducing the pure lemon-yellow of the 
original culture. 
Experiment XV.—Extraction. Contamination with the 
micrococcus of osteomyelitis. Suppuration. Phthisis bulbi. 
Dec. 16th.—Simple extraction. Contamination of the wound 
with a three-weeks-old, yellow culture of an emulsion, the micro- 
coccus of osteomyelitis, a drop being spread over the wound with a 
wire loop. The next day profuse purulent discharge, the upper 
part of the cornea whitish yellow, the wound gaping, anterior 
chamber filled with pus. During the next few days suppuration 
continued ; then it gradually disappeared. The cornea cleared 
from below upward, the hypopyon disappeared, the vitreous was 
yellowish white, at the closing wound there was a circumscribed 
purulent abscess of the cornea which disappeared in two weeks 
after the operation. Eyeball shrinking {from internal suppuration 
with partial destruction of the cornea'). 
The verifying eye, in which extraction with prolapse of the 
vitreous had been made, recovered in the usual way without 
irritation. H. Knapp. 
36 
In the secretion of the anterior chamber micrococci were 
freely demonstrated by dry-cover specimens and cultures. 
The latter developed white at first, but became yellow 
afterward, liquefied, cone-like, the jelly in the test-tube 
producing at the lower end a granular (at first white, then 
yellow) sediment; while on the surface of agar they devel- 
oped into neat, coalescing orange clusters, the true picture 
of staphyloc. pyog. aureus. These cultures were used for 
further inoculations. They showed the same properties 
and the same pyogenic energy as the original. 
Experiment XVI.—Extraction with an infected knife. 
Panophthalmitis. 
Dec. 24th.—Z, extraction, knife introduced three times, iris in 
the wound. 
R, section with a single introduction of a Graefe knife, previ- 
ously moistened with an emulsion of osteomyelitis coccus. The 
culture was orange-colored, and showed under the microscope 
small cocci—single, double, and in short chains. 
Dec. 25th.—Z, wound clean, plugged with iris. Upper part of 
cornea profusely gray. Neither congestion nor secretion. R, 
purulent secretion, wound gaping, in it a black bead of vitreous. 
Lower two thirds of cornea filled with pus. 
The left eye recovered smoothly. In the right panophthalmitis 
developed with total destruction of the cornea. 
Experiment XVII.—Discision with an infected needle. 
Panophthalmitis. 
Dec. 24th.—Z, discision of lens with a needle. R, the same, 
the needle having previously been moistened with an emulsion of 
the fungus of osteomyelitis. 
Dec. 25th.—Z, opacity of lens without irritation, puncture of 
cornea clean, iris normal. R, closed, purulent discharge on sepa- 
rating the lids. Cornea around puncture swollen, infiltrated with 
pus. Streaky, purulent exudation in the shallow anterior chamber. 
Eye swollen. 
Dec. 25th.—R, profuse sanguino-purulent discharge on forcible 
separation of the swollen lids. Eye swollen, cornea opaque. 
Pus in the pupillary space and in the lower part of the anterior 
chamber. 
Jan. 2, 1886.—Right eye lost from panophthalmitis ; the left 
has remained free from inflammation. 37 
Action of Bacteria on Operations of the Eye. 
EXPERIMENT XVIII.—Extraction. Pressing out of the 
lens with infected lids. Panophthalmitis. 
Dec. 2 Zth.—Z, ordinary extraction. P, the same ; after an 
emulsion of osteomylitis coccus had been freely applied to the 
conjunctival sac and over the edge of the upper lid. When the 
corneal section, which at the same time had opened the capsule, 
was completed, the lens was pressed out with the edges of the lids, 
and the remnants of the lens were wiped out of the wound with 
the edge of the upper lid. 
Dec. 29th.—Z, large prolapse of iris, covered with a streak of 
mucus which, when drawn away with a pair of forceps, left a 
smooth, clean surface. Cornea in the neighborhood of the section 
diffusely opaque. Pupil and iris clear. The eye recovered with- 
out irritation. R, excessive purulent secretion ; thin, turbid liquid 
escaped even from the nose. The whole cornea white ; the wound 
and protruding iris white, bathed with pus. 
fan. 2, 1886.—Most pronounced panophthalmitis. 
The pus taken from the wound the day after the opera- 
tion, presented under the microscope an immense quantity 
of cocci. 
Experiment XIX.—Needle inoculation with the micro- 
coccus of osteomyelitis. Circumscribed abscesses. Recovery. 
Dec. 28th.—Three punctures of the corneal substance, without 
perforation, were made with a Graefe knife, the point of which 
had been previously dipped into an emulsion of the coccus of 
osteomyelitis. 
Dec. 29th.—Moderate discharge. The three punctures are 
white, raised, from two to four millimetres in diameter. 
Dec. 30th.—The three points have developed into prominent 
corneal abscesses. Hypopyon filling the lower third of the an- 
terior chamber. 
Dec. 31^.—Abscesses smaller, cornea clearing ; no secretion. 
fan. 4, 1886.—Abscesses very small, circumscribed opacities. 
Under cocaine a small quantity of the contents of the 
absorbing abscess was removed with a needle and examined 
in dry-cover glass specimens, stained with aniline. It showed 
an immense quantity of small, feebly-stained, somewhat ir- 
regular granules (cell detritus and dead cocci). H. Knapp. 
38 
EXPERIMENT XX.—Five needle-pricks in the cornea, fun- 
gus of osteomyelitis painted over them ; only one develops into 
a pustule, which gradually disappears. 
Dec. 28th.—With a clean Graefe knife the cornea is pricked in 
five points and then repeatedly painted with an emulsion of the 
coccus of osteomyelitis by means of a wire loop. 
Dec. 29th.—The whole cornea clouded, but only one prick is 
white. Slight secretion. 
Dec. 30th.—The white, infiltrated point somewhat larger than 
the day before ; the remainder of the cornea clearer. 
Dec. 30th.—The circumscribed infiltration smaller. 
fan. 1, 1886.—Still smaller and covered with epithelium. 
Its contents scraped out with a needle and microscopi- 
cally examined showed the same detritus as in the preced- 
ing case. 
EXPERIMENT XXI.—Painting of a healing scar with micro- 
cocci of osteomyelitis. No reaction. 
Dec. 28th.—An emulsion of recently cultivated osteomyelitis 
cocci, which, in other experiments, had proved very efficient, was 
spread by means of a wire loop repeatedly over the iris, which 
filled the clean extraction-wound of the left eye of a rabbit operated 
on twelve days previously (Expt. XV., verifying eye). Abso- 
lutely no reaction followed. The next day the eye looked whiter 
and the scar was cleaner and smoother than before. 
Experiment XXII.—R, extraction with an infected 
knife ; L, extraction with the same knife, over which a cur- 
rent of water had been running a quarter of a minute. Pan- 
ophthalmitis on both sides. 
Dec. 29th.—On the right eye, extraction with a Graefe knife 
previously dipped into an emulsion of micrococci of osteomyelitis. 
On the left eye the same operation, with the same knife, over 
which a stream of ordinary water from a hydrant had just before 
been running for a quarter of a minute. 
Dec. 2,0th.—Purulent iridokeratitis in both eyes, L even more 
than R. Purulent secretion marked. 
Jan. 2, 1886.— Infiltration of the flap limited in both eyes, right 
almost disappeared. Both cornese and anterior chambers opaque. 
Irides and pupils not to be seen. The purulent inflammation ex- 
tends no doubt to the deeper parts. 39 
Action of Bacteria on Operations of the Eye. 
Jan. 4, 1886.—Panophthalmitis in both eyes with preservation 
of the cornea. 
Examination of the secretion of the wound showed the 
leucocytes loaded with cocci. 
Experiment XXIII.—R, extraction with an infected 
knife. Panophthalmitis. L, extraction with the same knife 
after it had been washed with water and wiped clean with 
a towel. Recovery without irritation. 
Dec. 2gth.—R, extraction with a Graefe knife previously dipped 
in an emulsion of the coccus of osteomyelitis. Z, the same opera- 
tion with the same knife which had just been washed in ordinary 
hydrant water, washed clean, and polished with a recently washed 
ordinary towel of the anatomical laboratory. 
Dec. 30th.—R, suppuration in the wound marked as usual ; L, 
no secretion, no irritation. Iris in the wound clean. Upper part 
of cornea cloudy, the lower two thirds, the pupil and iris clear. 
Jan. 2d.—R, panophthalmitis ; Z, no irritation. 
Jan. Afth.—Z, smooth recovery. 
Experiment XXIV.—Emulsion of pyogenic cocci put into 
the conjunctival sac. Extraction and paracentesis with a clean 
knife. Suppuration in both cases. 
Dec. 2gth.—An emulsion of a fresh culture of the fungus of 
osteomyelitis is dropped repeatedly into the upper and lower parts 
of the conjunctival sac and painted over the cornea. Two min- 
utes later the lens is extracted from the left eye with a sterilized 
Graefe knife, and with the previously heated blade of the same a 
paracentesis of the anterior chamber and a puncture into the sub- 
stance of the cornea of the right eye are made. By the next day the 
left eye presented the usual wound suppuration, and the right well- 
marked abscesses as the punctures. Purulent secretion in both. 
The extraction-wound causes panophthalmitis ; the corneal ab- 
scesses cause hypopyon in the next few days, burst on the outer 
surface, and disappear, leaving cicatrices. 
Jan. \th.—The contents of the abscess, obtained with 
a needle, show in the dried and stained cover-glass speci- 
men distinct colonies of irregular, evidently decaying 
cocci. 
Experiment XXV.—Squint-operation ; infected. Phleg- 
mon. Recovery. H. Knapp. 
40 
Dec. 2$d.—I made a subconjunctival tenotomy of the upper 
straight ocular muscle of a rabbit and introduced with a wire loop 
a very small quantity of a culture of osteomyelitis coccus. 
Dec. 2\th.—Purulent secretion on the lids and in the conjunc- 
tival sac. The regions of the wound swollen, whitish yellow, its 
neighborhood congested, cornea clear. 
Dec. 25th.—No secretion, cornea clear, region of the divided 
muscle greatly swollen (abscess). 
Jan. 2, ’86.—The phlegmon discharged a good deal of thick 
yellow matter. The cornea clear, and the region of the wound 
less swollen and red. 
Jan. 4, ’86.—Swelling and suppuration have almost dis- 
appeared. 
Cultures of the pus taken the day after the operation grew 
luxuriantly and showed on Jan. 4th pure cocci. 
Reviewing these cases in groups we arrive at the following 
results : 
1. Two cases of discision with injection of a drop of an 
emulsion of pyogenic cocci into the anterior chamber 
(exp. V. and VI.). The operation was immediately fol- 
lowed by the most intense primary suppuration in the ante- 
rior chamber with purulent maceration of the cornea and of 
all interior parts of the eye. Both animals looked ill, the 
one died on the sixth day, the other recovered and was 
killed on the thirteenth. Under the microscope and by cul- 
tivation cocci were discovered in the pus, the cornea, and 
inner membranes ; besides that, cultures developed from the 
optic nerves, the chiasm, one optic tract, and the lens of the 
other eye, though I did not succeed microscopically in de- 
monstrating cocci in these and other parts of the body, nor 
in the blood. It surprised me to see short bacilli develop in 
some cultivations that were taken from parts behind the 
eye, while others reproduced the injected micrococcus of 
osteomyelitis, which I cannot but consider to be identical 
with the staphyl. pyog. aureus on account of the indentical 
morphological, biological, and pathogenic properties they 
have in common. I desire to mention here the interesting 
experiments of Deutschmann,1 who after injection of large 
1 Experimenteller Beitrag zur Pathogenese der sympathischen Augenentziin- 
dung, Gtaefe's Arch.., Bd. xxvii., ii., pp. 291-300, 1882. Zweiter Artikel, Ibidem, 41 
Action of Bacteria on Operations of the Eye. 
quantities of pyogenic fungi into the vitreous of one eye 
could observe their migration with concomitant inflamma- 
tion through the optic nerve of the infected eye, the chiasm, 
and the optic nerve of the other eye into the posterior seg- 
ment of the latter. All his animals died in a few days. 
I would dwell on these interesting and suggestive investiga- 
tions as well as on Deutschmann’s bacteriological researches 
of enucleated human eyes if it lay within the scope of my 
subject. The object of my experiments is not to find the 
paths by which micro-organisms travel through the organs 
of the body, but to determine their pyogenic properties with 
special reference to the operations of the eye. These prop- 
erties manifest themselves most strongly when the organisms 
are injected through a small wound into the interior of the 
eye and are there retained, a fact which is in harmony also 
with the experiments of Deutschmann. 
2. A discision with an infected needle (exp. XVII.) was 
followed by severe primary suppuration in the track of the 
needle through the cornea and in the anterior chamber, and 
loss of the eye. It is evident from this observation that, 
under certain conditions, the quantity of the infecting ma- 
terial may be small, the traumatism insignificant, and yet 
the suppuration marked and extensive. Cases of suppura- 
tion from discision, especially in old secondary cataracts, have 
occurred several times in my own practice ; I have also seen 
them (even last year) in the practice of others that operate 
antiseptically, so that an introduction of pyogenic germs 
could, it seems, be excluded. To enter more deeply into 
this question would, in this place, lead me too far. I desire 
only to remark that these cases resembled those in which a 
foreign body, a scar, a small prolapse of iris, or an iridencleisis 
not visible exteriorly may have existed without irritation for 
many years, and then suddenly produce suppuration after 
very insignificant traumatism, or, indeed, without assigna- 
ble cause. Recent investigations seem to make it probable 
that, in some cases, the suppuration after discision is not due 
Bd. xxix., iv., 261-270, 1883. Dritter Artikel, Ibidem, Bd. xxx., iii., pp. 77 to 
122, 1884. Erster Nachtrag, Ibidem, Bd. xxx., iii., pp. 331-336, 1884. Zwei- 
ter Nachtrag, Ibidem, Bd. xxx., iv., pp. 315-317, 1884. Vierter Artikel, 
Ibidem, Bd. xxxi., ii., pp. 270-290, 1885. H. Knapp. 
42 
to fresh introduction of pyogenous elements with the needle, 
but to older, latent local deposits of cocci, or to their pres- 
ence in the humors of the organ or the whole body, so that 
the traumatism is to be regarded only as one of the condi- 
tions by forming a locus minoris resistentiae. Among these 
investigations I may mention those of Becker,1 F, Krause,2 
and Rosenbach,3 who, after simple fractures in animals, 
have seen suppuration occur only when osteomyelitis micro- 
cocci were injected into the veins. Also the experiments 
on ulcerous endocarditis recently communicated by Orth,4 
at the Society of Naturalists and Physicians, at Strasburg, 
may serve to lend weight to this supposition. When he 
and Dr. Wyssokowitsch pierced the aortic valves from the 
carotid with a blunt-pointed probe, neither endocarditis nor 
thrombotic deposits occurred at the injured place; but 
when pyogenic organisms were injected into the vein of 
the ear simultaneously, or one or two days later, acute 
endocarditis with metastatic abscesses developed, of which 
the animals died in from two to five days. The organisms 
did not settle at certain places arbitrarily but only where a 
previous disturbance had caused a predisposition. This 
tendency may be produced by very insignificant mechanical 
injuries, for the organisms did not settle on the lacerated 
valves only but also on the large vessels over which the 
knob of the probe had slid. By such and similar experi- 
ments the old doctrine of “ impure humors ” gains a visible 
form. If we call this process constitutional or indirect in- 
fection of a wound, the possibility of which, according to 
what has been said, can scarcely be denied, our experi- 
ments positively demonstrate the importance of direct in- 
fection even by instruments of the smallness of a division 
needle. 
3. Three cases (XIX., XX., and XXIV.) of inoculation by 
pricks of a needle, and paracentesis. These inoculations 
caused circumscribed corneal abscesses with so much the 
1 Vorlaufige Mittheilung, etc., von Struck, Deutsche med. Wochenschr., 1883, 
No. 46. 
2 Fortschritte der Medicin, 1884, No. 7 u. 8. 
3 Wundinfectionen des Menschen, Wiesbaden, 1885. 
4 Tageblatt, page 58, Strasburg, 1885. 43 
Action of Bacteria on Operations of the Eye. 
more certainty as the micro-organisms were introduced the 
more directly and probably also the more plentifully and 
deeply into the corneal substance. The paracentesis with 
an infected needle caused the largest abscess, the inocula- 
tion pricks with an infected needle produced well-developed 
pustules, whereas, of the five punctures with a clean needle, 
after which the emulsion of microbes was immediately 
painted over the cornea, only one developed into a circum- 
scribed purulent exudation which soon disappeared. I may 
mention in connection with this that I painted an emulsion 
of pyogenous bacteria over the corneae of a guinea-pig and 
some rabbits after I had made superficial scratches in the 
cornea with a knife, but produced no more than a transient 
opacity without suppuration. 
Inoculations of the cornea have been made by F. Krause 
and Passet. Krause1 says : “ If the cornea is inoculated by 
making a small pouch into the corneal substance with a 
division needle, previously brought to a glow, an in- 
filtration of the cornea occurs, which in most cases disap- 
pears in a short time. In two eyes out of twelve hypopyon 
formed. In the pus of the enucleated eye no micro-organ- 
isms were found and the planting of pus from the hypopyon 
on agar-agar yielded a negative result.” I can say the same 
of a case in which hypopyon formed three weeks after an 
extraction that had healed with a smooth scar. In the pus, 
aseptically obtained by paracentesis of the cornea, no micro- 
organisms could be detected in dry cover specimens and 
four gelatine plates charged with it showed no trace of 
growth. These observations harmonize with the investiga- 
tions of R. Koch, A. Ogston,2 and others who found cocci 
in the pus of acute abscesses only. 
R. Koch, in his classical monograph, “ Investigations on 
the etiology of diseases by wound infection,” 3 describes the 
whole process of the formation of abscesses in a very clear 
manner. The bacteria are met with in large numbers in the 
abscess wall and the near vicinity whereas the caseous con- 
‘1 Fortschritte der Medicin, 1884, p. 228. 
2 Ueber acute Abscesse, Archiv f. klin. Chirurgie, Bd. xxv., Heft 3, p. 588, 
1880, und an verschiedenen Orten im Brit. Med. Jourti. 
3 Leipzig, 1878, p. 51, u. f. H. Knapp. 
44 
tents are made up of cell detritus and dead, scarcely recog- 
nizable cocci. 
Passet 1 noticed, after inoculation punctures with staphy- 
loc. pyog. aureus (/. c., p. 21), albus (p. 25), and citreus (p. 
27), whitish-gray, circumscribed exudations which disap- 
peared in from four to ten days, leaving a speck. 
The necessity of a certain quantity that must not be too 
small to render inoculations efficient, is not only demon- 
strated by my experiments but has been noticed and dis- 
tinctly pointed out by many others. F. Krause2 says: 
“ No reaction occurs if a small quantity of a pure-culture is 
put, without attenuation, into a pouch in the skin of a rab- 
bit, guinea-pig, or mouse, with a platinum needle previously 
heated. 
4. Negative experiments with pyogenic material 
(exp. VIII., XXI., and XXIII.). Pus was put into an in- 
cision through the cornea and iris of a guinea-pig. It was 
taken from a rabbit affected with acute corneal suppuration 
and certainly was not sterile, for at the same time much 
smaller quantities of it were used for needle cultivations 
which not only developed vigorously, but wounds inocu- 
lated with these cultivations suppurated freely. There 
remains no other possibility than to assume that the in- 
oculated quantity was insufficient at least for this guinea- 
Pig- 
A very strong emulsion of osteomyelitis fungus (expt. 
XXI.) was painted freely over the cicatrizing wound of a 
rabbit, without any effect. The wound may have been en- 
tirely covered with epithelium and thus protected, but I 
have recently seen (in the above-mentioned case of hypop- 
yon, where the pus contained no cocci) the apex of a cor- 
neal flap become white about twelve days after a cataract- 
extraction, the cicatrix up to that time having been per- 
fectly free from irritation. The infiltration disappeared in 
three or four days, but a week later hypopyon made its 
appearance without any abnormity to be noticed in the 
cornea or iris. The patient suffered from chronic conjunc- 
1 Untersuchungen liber die eitriger Phlegmone des Menschen. 
Berlin, 1885. 
3 Fortschritte der Medicin, 1884, p. 227. 45 
Action of Bacteria on Operations of the Eye. 
tival catarrh, but had been treated and operated on under 
strict antiseptic precautions. The other eye, operated on 
shortly before by a very skilful hand, had been lost through 
intense iritis and iridocyclitis. If we are loath in this 
anaemic patient to accuse impure humors, we are forced to 
assume that pyogenous fungi from the conjunctival sac 
must have subsequently infected the incompletely closed or 
partially reopened wound, and migrating through the fresh 
scar to the ciliary body produced a purulent cyclitis. How 
much the susceptibility varies in different species of animals, 
even in different individuals of the same species, has long 
been known. The most striking example of this fact with 
reference to bacteriology is the observation made by R. 
Koch and reported in his “Diseases by Wound Infection,” 
1878, that the smallest quantity of the bacillus of mouse 
septicaemia kills the house-mouse, but has no influence on 
the field-mouse. Expt. XXIII. shows a regular primary 
suppuration after an infection of the blade of the knife, 
whereas an extraction made on the other eye with the same 
blade, after it had been washed and polished with a clean 
towel, healed without irritation. The instrument after this 
simple cleansing proved sterile with reference to the 
inoculation of this rabbit. I do not venture to maintain 
that this kind of sterilization suffices for all rabbits or all 
men, but according to recent investigations1 this seems to 
be the case for surgical instruments in general and especially 
for polished ones. 
5. Insufficient cleansing of an instrument. In connec- 
tion with the preceding remarks the following observation 
(expt. XXII.) is of particular importance. The right eye 
of a rabbit was lost by primary suppuration after extraction 
of the lens with a Graefe knife that was contaminated with 
an emulsion of osteomyelitis fungus. The extraction of the 
lens of the left eye with the same knife, though after the 
operation on the right a stream of hydrant water had been 
1 Gartner u. Plagge : Ueber die desinficirende Wirkung wasseriger Carbol- 
saurelosungen. Verhandl. der Deutschen Gesellschaft fur Chirurgie. Berlin, 
Hirschwald, 1885, II. p., 1-11. 
H. Kiimmel: Die Bedeutung der Luft- u. Contactinfection fur die practische 
Chirurgie. Ibidem, II., p. 430-446. H. Knapp. 
46 
running over it, produced a suppuration no less intense. 
The water of the new Berlin water-works, which at present 
is remarkably pure, can scarcely have been the cause of 
the suppuration, and we must assume that the micrococci 
adhered so firmly to the steel as not to be swept away by 
a simple stream of water, whereas washing of the blade 
with the fingers and polishing it with a towel removes them 
thoroughly enough. 
Experiments on that point, with special reference to 
ophthalmological practice, would be highly desirable. How 
surely is sterilization effected, i. by ordinary cleansing? 2. 
heat, of what degree, and how long? 3. absolute alcohol? 4. 
carbolic acid? 5, corrosive sublimate? 6. boric acid, etc. 
How surely do these chemicals sterilize, with or without 
previous ordinary cleansing of an infected instrument ? The 
examination should be made according to the different 
methods of cultivation, inoculation, and operations, of 
course with strict observance of the rules of bacteriology. 
The above-mentioned experiments of Gaertner, Plagge, and 
Kiimmel might be used for comparison. 
6. Incisions through cornea, iris, and adjacent part of 
the lens. Inoculation with different pyogenic bacteria. 
Four cases (exp. VII., X., XI., and XII.), all lost by primary 
suppuration. 
7. Four cases of extraction, the wound infected with 
different pyogenic bacteria (exp. XIII., XIV., XV., and 
XVI.). Suppuration in all. The verifying operations in these 
two groups, though performed in the most extensive and 
unsparing manner, were followed by prolapse of iris, tran- 
sient diffuse gray opacity of the flap, but no suppuration. 
8. Subconjunctival squint-operation (exp. XXV.). This 
operation also, after inoculation with the pyogenous fungus, 
was followed by primary suppuration. Fourteen years ago 
I made a subconjunctival tenotomy in a boy who, after the 
operation, on a cold winter day, travelled three hours in a 
carriage, vomiting frequently (he had been anaesthetized 
with chloroform) and held his head out of the carriage. 
On the third day I was called, and found a phlegmonous 
inflammation like the one in our rabbit, which was recov- 47 
Action of Bacteria on Operations of the Eye. 
ered from, but left a divergent strabismus. At the time I 
attributed this to the influence of the long drive in the cold. 
Last summer I saw a subconjunctival tenotomy followed by a 
small pustule at the upper end of the wound canal, under 
the unbroken conjunctiva. It burst and disappeared with- 
out inconvenience in a few days. In drawing the attention 
of the assistants and students to this case, I remarked 
that scarcely any other explanation could be given than in- 
fection by the introduction of germs with the instruments. 
I do not recall other cases of suppuration after tenotomy (I 
have made about 3,000), and certainly no loss has occurred. 
Be the number ever so small, our experiment and the just- 
mentioned cases demonstrate that primary suppuration 
from infection may occur even after a simple conjunctival 
squint-operation. 
9. Operations after infection of the conjunctival sac 
(exp. IX. and XVIII.). In addition to the above-cited cases 
of extraction and paracentesis (exp. XXIV.), and the case re- 
ported on sub. 3, two others are still to be mentioned. In 
exp. IX. small quantities of a staphyloc. growth were put into 
different parts of the conjunctival sac by means of a wire 
loop. A section through cornea and iris made several min- 
utes later healed without any reaction by immediate union. 
In the second case I put an emulsion of staphyloc. freely into 
the conjunctival sac, spreading it especially over the free 
edge of the upper lid. After the section and the simultaneous 
opening of the capsule, I pressed the lens ont with the lids, 
and wiped the remnants out of the wound with the edge of 
the upper lid. The operation had been cautiously done, 
the removal of the lens was complete, the wound closed ad- 
mirably, but there was intense suppuration the next day. 
Among all the faulty manipulations of which in the 
course of years, in explanation of the failures in my cataract- 
operations, I have accused myself, I consider, from a bac- 
teriological point of view, none so prejudicial as this appar- 
ently so gentle and innocent manoeuvre of rubbing the 
remnants of the lens out of the wound with the upper lid. 
It is certainly very rare that many pyogenic micro-organ- 
isms lodge on a healthy eye and its appendages, but if any H. Knapp. 
48 
are present they are in all probability located on the edges 
of the lids more than anywhere else, and carried in the 
most direct manner into the wound by this mode of wiping 
away the remnants of cataract. If we hesitate to give up 
these external manipulations on account of their efficiency 
in removing remnants, we should take care not to let the 
edge of the upper lid come in contact with the open 
wound, how carefully soever it may have been bathed in- 
side and out with corrosive sublimate. 
To finish I may be allowed to make some 
CONCLUDING REMARKS. 
It has been on my part, as on that of many others, 
a great mental struggle to abandon the mechanical 
theory of suppuration. From the beginning I have appre- 
ciated the advantages of antiseptics in surgery so highly 
that in 1871 I went to Edinburgh for the special purpose of 
acquainting myself with Lister’s method by personal obser- 
vation. When I asked the great surgeon whether much 
benefit might be derived from this method in ophthalmic 
surgery he answered that he did not think so. The oper- 
ations on the eyeball are mostly small; the territory is so 
well protected that after the closure of the lids the condi- 
tions resemble pretty closely those of a pure subcutaneous 
operation ; furthermore, the conjunctival sac is constantly 
bathed in an antiseptic fluid, the tears; there is little occa- 
sion to contaminate the wound with hands, dressing 
materials, or instruments difficult to keep clean ; the opera- 
tions are soon over, and, therefore, exposed to injurious 
influences for a short time only ;—all this explains why the 
results obtained by careful operations without the use of 
antiseptic agents have not been inferior to the results of 
those that have imitated the antiseptic methods of general 
surgery. In ophthalmology, as in general surgery, opera- 
tions and dressings may be antiseptic without the employ- 
ment of chemical means, antiseptics—witness the unsur- 
passed results of Lawson Tait. Moreover, it is to be borne 
in mind that a new idea thrown into the world commonly 
causes more harm by having its proper limits of application Action of Bacteria on Operations of the Eye. 
49 
transgressed than would come from disregarding it, a fact 
which is illustrated by the first period of antiseptics in 
ophthalmology. In the course of years, however, the anti- 
septic method has not only brilliantly maintained its princi- 
ple, but divested itself of much that was burdensome and 
immaterial, and it has conquered more and more ground. 
Its triumphs have been an incentive to thorough scientific 
researches in the domain of bacteriology. Although it was 
a number of years ago that some surgeons made the start- 
ling statement: “ No suppuration without micro-organisms,” 
and in spite of the recent investigations of Orthmann,1 J. A. 
Ruys,2 Scheuerlen,3 Klempener,! and others, do we not yet 
find many pathologists who are prepared to accept this state- 
ment without reserve ? It is sure, however, that the other 
causes claimed for suppuration are steadily losing ground, and 
even conservatively disposed natures that have followed the 
discussion of this highly important scientific question must 
ask themselves : Will not the pyogenic fungi control their 
domain as uncontestedly in future as the fermenta- 
tion fungi control theirs now ? Certainly nobody has ever 
doubted that micro-organisms may produce suppuration, 
but the microbes were believed to be one of many irritants 
that have this effect. The above experiments, made accord- 
ing to the methods used in the bacteriological laboratories 
of Berlin, have had for their object to ascertain by plain 
demonstration how far mere traumatism carried to its 
utmost limits can be made responsible for the formation of 
pus in the limited field of eye operations, and how far the 
pyogenic species of bacteria that have been purely cultivated 
during the last few years are concerned in suppuration. 
The experiments without exception have sustained the 
bacteriological influence on the formation of pus. I have 
reported them as they have appeared, leaving it to the 
reader to draw practical conclusions from them. Yet I 
should not omit to point out that this field of experimenta 
tion, already so happily cultivated by Eberth, Leber, 
1 Virchow’s Arch. 
3 Deutsche med. Wochenschr., No. 48, Nov. 26, 1885. 
3 Arch. f. klin. Med., Bd. xxxii., p. 500. 
4 Zeitschr. f. klin. Med., Bd. x.f 1 u. 2. Deutschmann, and others, is likely to yield the most import- 
ant results, particularly now that the methods of investiga- 
tion have gained accuracy and system chiefly through the 
genius of R. Koch.1 
H. Knapp. 
50 
1 To those that wish to make themselves acquainted with the present stand- 
point of practical bacteriology the following works may be recommended : 
Hiippe, “ Methoden der Bacterienforschung.” 3 Aufl. Wiesbaden, 1886. 
Hiippe, “ Formen der Bacterien.” Wiesbaden, 1886. De Bory, “ Vorlesun- 
gen uber Bacterien.” Leipzig, 1885. J. S. Woodhead and W. H. Hare, “ Prac- 
tical Mycology.” Edinburgh, 1885. Cornil-Babes, “ Les Bacteries.” Paris, 
1885. PUTNAMS’ PRINT