Germany has come to occupy so large a place in progressive medicine
during the last half-century that it is rather hard to conceive of a
time when the Teutonic race was not the head and front of modern
medical progress. The leadership that had existed in Italy for over
five centuries only passed to Germany at the beginning of the
nineteenth century. The first great leader in German medical thought
was Johann Mueller, and to the wonderful group of students that
gathered around him German medicine owes the initiative which
gradually forced it into the prominent place it still holds in the
world of medicine. The great institutions of learning that have since
come in Germany did not exist with anything like their modern
systematic arrangement when Mueller began his work. It was the
marvellous influence of the man as a teacher, and not the scientific
aids afforded by institutional methods, that brought forth the great
generation of teachers which followed immediately on Mueller's
footsteps. Nowhere more than in the life of Mueller can it be
recognized with absolute certainty that the system and the institution
count for little in education, as compared to the man and his methods.
The keynote of Mueller's career, even more than what he did for
biology, and for all the biological sciences related to medicine, is
the wonderful conservatism of thought which characterizes his
scientific conclusions, while at the same time he began the
application of the experimental methods {218} to medicine as they had
never been applied before. At a time when physiologists, because of
Woehler's recent discoveries of the possibility of the artificial
manufacture of urea, might easily have been led to the thought that
life counted for little in the scheme of the universe, Mueller
continued to teach consistently that vital energy may direct chemical
or physical forces, but must not be confounded with them. It looked as
if in the development of the chemistry of the carbon compounds, all of
which are the result of life action, that materialistic views must be
expected to prevail. Mueller insisted, however, that life ever remains
the guiding principle which rules and coordinates all the physical and
chemical forces at play, within living organisms; and that the vital
principle is entirely independent of these forces so closely attached
to matter.
All Mueller's disciples, and they were the representative biological
scientists in Germany during the nineteenth century, followed closely
in his footsteps in this matter, and the result was a conservatism of
thought in biology in Germany that is the more surprising when we
realize how much German philosophers in their systems emphasized the
necessity for absolute independence from all previous systems of
philosophical speculation. It is so much more interesting, then, to
find what was the method of education that made of Johann Mueller so
conservative a thinker, while not injuring his genius for experimental
observations. The influences that were at work in his earlier years
were evidently those that made him subsequently the bulwark against
materialistic tendencies in biology, and yet did not impair his
originality. His early education was obtained under influences that
are usually considered to be distinctly harmful to independence of
thought, and yet they seemed to have helped him to the fulfilment of
his destiny, as a great thinker and investigator. {219} Mueller is
undoubtedly one of the very great men of modern science, and is the
recognized founder of the system and methods of investigation which
have given German medicine its present prominence and prestige.
In recent years there have been many tributes to Mueller, because as
Virchow's teacher it was considered that some of the praise for the
work done by Virchow must naturally reflect on the man to whom the
great German pathologist acknowledged that he owed so much of his
inspiration and his training in methods of investigation. Virchow's
death too very naturally led to the recall of what had been
accomplished in German medicine during the nineteenth century, and for
much of this Johann Mueller must be considered as at least indirectly
responsible, since to him so many of the great German medical
scientists owed their early training. These men, all of them, did not
hesitate to attribute the progress of German medicine to the methods
introduced by Mueller. At the beginning of the twentieth century
something of the estimation in which he was held in a land far distant
from the German Fatherland may be gathered from the following tribute
paid to him in a recent meeting of the Medical Society of the State of
New York by Dr. C. A. L. Read, of Cincinnati, former President of the
American Medical Association. In the midst of his panegyric of Virchow
Dr. Read described in some detail the medical faculty of Berlin at the
time when Virchow was beginning his work as a student at that
University. He said:
"In the faculty there were Dieffenbach, the foremost surgeon of his
day; Schoenlein, the great physician who had come from Zurich the
same year to join, not only the teaching body, but to act as a
reporting counsellor for the ministry and to serve as
physician-in-ordinary to the King; Froriep, who was in charge of the
Pathological Institute; Caspar, who {220} was also medical
counsellor, with a seat in the special deputation for medical
affairs in the ministry; but towering above them all was the
intellectual figure of Johann Mueller, the Professor of Physiology.
He was an original genius with daring, actually engaged in winnowing
the wheat of demonstrated truth from the prevailing chaff of
egoistic opinion which divorced physical science from speculative
philosophy. Prompted by the inspiration which he had derived in turn
from Bichat and the French school, the Professor of Physiology was
busily retesting in the laboratory truths previously elaborated by
Haller, Whytt, Spalanzani, Cullen, Prochaska, John Hunter, the
Bells, Magendie, Berzelius and Bichat himself."
This is the tribute to Johann Mueller, nearly fifty years after his
death. That of Virchow, at his obsequies in Berlin, is even more
enthusiastic. Virchow, then at the age of thirty-seven, at the height
of his powers, already acknowledged the greatest of living
pathologists, just recalled to Berlin to become Professor of Pathology
in the University which he had left more or less in disgrace because
of his political opinions, could not say too much of the teacher whom
he respected and honored so highly and whose inspiration he felt stood
for so much in his own career.
He said:
"My feeble powers have been invoked to honor this great man whom we
all, representatives of the great medical family, teachers and
taught, practitioners and investigators, mutually lament and whose
memory is still so vividly with us. Neither cares by day nor labors
by night can efface from our mind the sorrow which we feel for his
loss. If the will made the deed, how gladly would I attempt the
hopeless task of proper appreciation. Few have been privileged, like
myself, to have this great master beside them in every stage of
development. It was his hand which guided {221} my first steps as a
medical student. His words proclaimed my doctorate and from that
spot, whence now his cold image looks down upon us, his kindly eyes
beamed warmly upon me, as I delivered my first public lecture as
Privat-Docent under his deanship. And, in after years, I was the one
out of the large number of his pupils who, by his own choice, was
selected to sit beside him within the narrow circle of the faculty.
"But how can one tongue adequately praise a man who presided over
the whole domain of the science of natural life; or how can one
tongue depict the master mind, which extended the limits of his
great kingdom until it became too large for his own undivided
government? Is it possible in a few short minutes to sketch the
history of a conqueror who, in restless campaigns, through more than
one generation, only made use of each new victory as a standpoint
whereon he might set his feet and boldly look out for fresh
triumphs?
"Yet such is the task to which we are called. We have to inquire
what it was that raised Mueller to so high a place in the estimation
of his contemporaries; by what magic it was that envy became dumb
before him, and by what mysterious means he contrived to enchain to
himself the hearts of beginners and to keep them captive through
many long years? Some have said--and not without reason--that there
was something supernatural about Mueller, that his whole appearance
bore the stamp of the uncommon. That this commanding influence did
not wholly depend on his extraordinary original endowments is
certain, from what we know of the history of his mental greatness."
Virchow's tribute could not well be more enthusiastic or more ample.
His appreciation has been the standard for all other medical opinions
of the man. How much Mueller is honored at the present time in Germany
can be best {222} appreciated from the number of times that his name
is mentioned with respect and often with laudation in the proceedings
of German medical societies. Scarcely a meeting passes in which more
than once Johann Mueller is not referred to as the founder of the
scientific method in medicine which has given Germany her present
position in the very forefront of medical scientific progress. It is a
common expression, said half in jest it is true, but surely more than
half in earnest, that the proceedings of no medical society would be
really successful within the bounds of the German fatherland unless
they were hallowed by an invocation of the great name of Johann
Mueller, the revered patron of modern German medicine. This is no
witticism by exaggeration, after the American fashion, but a sincere
Teutonic expression of feeling that occupies German medical minds with
regard to the man who founded the most progressive school of modern
medicine, and in doing so brought honor to his native country.
Johann Mueller was born at Coblentz, on July 14, 1801. About six months
before, the Emperor of Austria by the treaty of Luneville, signed
February 9, 1801, ceded to the French Republic all the Austrian
possessions on the left bank of the Rhine. The electors of Treves, who
were archbishops and reigning princes and who had resided for
centuries at Coblentz, by this treaty disappeared forever from the
list of German rulers. When Johann Mueller was born, French prefects of
the Departments of the Rhine and Moselle took up their residence in
the old town which had been, since the beginning of the French
Revolution, a favorite dwelling place for the French nobility driven
from their homes by fear of persecution.
Mueller's father was a shoemaker and lived in a small house in the
street of the Jesuits, so called because the fathers had had a school
in it for many years. Johann was {223} not destined to receive his
education from the Jesuits, however, for the order had been suppressed
nearly thirty years before his birth, and did not re-establish itself
in the Rhineland for many years afterward. The circumstances of the
Mueller family were not such as to encourage hopes of a broad
education, though his father seems to have taken every possible means
to secure as much school training as could be obtained for his son.
The early death of his father promised to deprive Mueller of whatever
advantages might have accrued from family sacrifices, but his mother
was one of these wonderful women who somehow succeed in raising their
families well and affording their children an education in spite of
untoward circumstances.
Johann was the eldest of five children, with two sisters. He was very
proud himself of the fact, that while he took from his father a large,
strong, healthy frame and a dignified carriage, he had his mother's
skill for putting things in order, her constancy of enterprise and her
tireless faculty for hard work. After his father's death, his mother's
energy and good sense enabled her to carry on the business established
by the elder Mueller by means of assistants, and as Coblentz was the
centre of a district that during the Napoleonic wars was constantly
overrun with soldiery, the shoemaking trade was profitable.
Johann seems to have learned the trade, but his mother succeeded in
enabling him to begin his education seriously at the age of eleven or
twelve. About this time, Joseph Goerres, who was afterward the great
leader of Catholic thought in Germany, and after whom is named the
famous Goerres Gesellschaft which stands for so much in German Catholic
life and progress, was a professor in the Sekunden Schule, or
secondary school, in Coblentz, and had recently published treatises on
natural philosophy with special {224} reference to physiology. Mueller
entered this school in 1810 and Goerres did not resign his
professorship until 1814, when owing to the publication of a political
work he was obliged to flee from the country. It is not known how much
influence Goerres exercised over young Mueller, but some at least of his
precious love for the natural sciences, which even in his student days
led to the making of natural collections of various kinds, seems to
have been imbibed under the influence of the philosopher physiologist.
The touching of the orbits of the two men, who were destined, more
than any of their fellow-citizens of Coblentz, to influence Germany's
future, must always remain an interesting consideration in the lives
of both.
Johann's parents were, as might have been expected, down in the old
Catholic Rhineland in the capital of the spiritual principality of
Treves, faithful members of the Roman Catholic Church. Very early in
life, Johann conceived the wish to become a priest. His mother,
rejoiced at her son's idea, was ready to make every possible sacrifice
to secure his education. It was with the intention of education for
the priesthood, then, that Johann entered the Sekunden Schule, an old
college of the Jesuits, in which Jesuit tradition and methods of
education still survived, and in which some of the old Jesuit pupils
seem still to have held positions even during Mueller's time as a
student (1810 to 1817).
It would appear probable that because of the traditions of Jesuit
teachings that held over at the school in Coblentz, and perhaps, too,
because of the presence of some of the old masters and teachers
trained by them, Mueller knew the ancient languages so well. He made
his own translations of Plato and Aristotle, and consulted the latter
especially always in the original and had a lifelong reverence for the
great Greek philosophic naturalist's work, Latin he used {225} so well
as to speak it readily, and practice in the disputations of the
University at Bonn made the language still more familiar to him. It
was said that he wrote Latin better than German. After the fall of
Napoleon the Prussian government took up the reorganization of the
schools in this part of the Rhineland, and Mueller became more
interested in scientific studies. At this time he became devoted to
mathematics, which he studied under the old pupil of Pestalozzi,
Professor Leutzinger, to whom Mueller, in the sketch of his life
prefixed to his thesis at the university, expressed the feeling that
he owed a special debt of gratitude.
During his school days Mueller became a collector, as we have said, of
natural objects. He was especially interested in butterflies for a
time, and collected all the species in the country around. He had a
curious dislike for spiders which remained with him all his life. He
was able to overcome this, however, and made important studies of that
insect's eyes, and of its changing expressions under the influence of
fear or when about to fall upon its prey.
His feeling with regard to the insect is an index of a certain
feminine quality of mind that had a characteristic expression in later
life in his dislike for vivisection. He could not bring himself to the
conclusion that animals must be sacrificed in the midst of horrible
pain unless there was some very definite scientific point to be
determined, and unless every precaution was taken to avoid inflicting
needless suffering. Even then he preferred that others should do this
work and more than once took occasion to point out the fallacy of
physiological observations founded on animal experimentation under
such anomalous circumstances, and insisted that very frequently the
results gave conclusions only by analogy and not by any strict logic
of animal similarity or absolute physiological nexus.
{226}
In a sketch of Mueller's life, by Professor Bruecke, of Vienna, himself
one of the most distinguished physiologists of the nineteenth century,
to whom the University of Vienna has paid the tribute of a marble bust
and tablet in its courtyard, the great Austrian physiologist sums up
very well the reasons for Mueller's fame. Professor Bruecke's tribute
may be found in the _Medical Times and Gazette_, of London, July 17,
1858. "If we inquire," he says, "what were the circumstances to which
Mueller, independently of his high intellectual endowment, his gigantic
power for work, the energy and massiveness of his character, and his
active and vigorous bodily constitution, owed the commanding position
he incontestably held among men of science in our day, we must admit
that before all things this was due to the breadth and depth of the
foundations upon which his intellectual cultivation had been built."
Professor Bruecke then dilates on the variety of scientific interests
which occupied Mueller's earlier years and the thoroughness with which
he accomplished everything that he set himself to.
A very curious reflection on our modern methods of education, and
especially the tendency to specialization and the formation of
specialists from their very early years, is to be found in Bruecke's
account of the extent and variety of Mueller's studies in all lines.
Far from considering that these diverse intellectual interests
hindered the development of his genius, he seems to consider that they
rather aided in the evolution of that largeness of mind characteristic
of the great genius. He says:
"In his schooldays Mueller's attention was directed to subjects of
study far beyond the mere medical curriculum, for we find him
attending the lectures of celebrated professors on poetry and
rhetoric, on the German language and literature, on Shakespeare and
Dante." As a matter of {227} fact, Bruecke seems to have understood
that no one is so little likely to make scientific discoveries as he
whose mind has been directed without diversion along the narrow lines
of a specialty in science. Constantly trained to see only what lies in
the sphere of this short-sighted interest, the mind never raises
itself to a view beyond the horizon of the already known.
The old classical training, supposed to be so useless in this
matter-of-fact, practical age, trained the minds of the men who have
given us all the great discoveries in science. The evolution of
intellectual power consequent upon the serious study of many things
proved an aid rather than a hindrance to future original work. Not one
of these great scientific investigators had at the beginning any hint
of the work that he was to do. It seems almost an accident that their
researches should have been conducted along certain lines which led to
important discoveries. What was needed for them was not special
training, but that mental development which puts them on a plane of
high thinking above the already known, to look for progress in
science.
Mueller continued for many years to entertain the idea of eventually
becoming a priest. At about the age of sixteen, however, he became
deeply interested in Goethe's work, and was especially attracted by
the great poet's studies of scientific subjects. About this time he
became interested in the collection of plants and animals and took up
seriously the study of physiology. Lavater's work was, at that time,
still sufficiently recent to have little of the novelty worn off, for
young students, at least. At the age of eighteen Mueller went to Bonn
and, when about to begin his university career, hesitated as to
whether he should study theology or not. His natural liking for nature
study, however, finally caused him to decide in favor of a scientific
career, and he began the study of medicine.
{228}
He took up his medical studies with the greatest enthusiasm. Under the
special guidance of Mayer, who besides being his teacher was a
personal friend, he applied himself zealously to the study of anatomy.
One of his expressions in his early student days that has often been
repeated, but which Mueller took the greatest care in later life to
correct and deny as a lasting impression, was the famous "Whatever
cannot be demonstrated by the scalpel, does not exist." The professor
of physiology at the time at Bonn was the famous Fredrich Nasse,
especially known for the wonderful attractiveness of his lessons and
his power of arousing enthusiasm in others, and it is not surprising
that Mueller, naturally so enthusiastic in scientific studies, should
have acquired a liking for the study that he never afterward lost.
During Mueller's second year of medical study the University of Bonn
announced its first prize, which was to be given for an investigation
of the subject of respiration in the foetus. Although Mueller was only
in his first year as a medical student at the time, he grappled with
the difficult subject and devoted all his spare time to arranging
experiments for the demonstration and investigation of doubtful
points. He received the prize, and Virchow, surely a good judge in the
matter, says that this work of his student days is distinguished alike
by the extent of its learning and by the number and boldness of the
experiments detailed. At the moment of his graduation, the young
doctor, in his twenty-first year, was already a marked man. From this
time on everything that he did attracted attention and had a ready
audience.
Mueller's mind was constantly occupied after this time with the
arranging of experiments to demonstrate natural principles. How far he
carried this habit of experimenting can be understood from some of the
habits of control over {229} his muscles which he had acquired by
continual practice and intense attention. He had thorough control over
the muscles of his ears and used often to amuse his fellow-students by
their movements. The anterior and posterior muscular portions of this
occipito-frontalis muscle were able readily to move his scalp and
produce curious disturbances in his hair. These habits of muscular
control many people have acquired. Other acquisitions of Mueller's are,
however, much rarer. He could, at will, contract or dilate his pupils,
having secured control over his iris by practice before a mirror, and
he could use the little muscles that connect the bones within the ear,
the hammer, anvil and stirrup, so as to make them produce an audible
click at will.
His habits of experimentation on one occasion at least placed him in a
rather ridiculous position. While making his military service, it
happened one day that when the command "Order arms" was given, Mueller
amused himself by inserting one finger after another into the muzzle
of his firelock. At last his middle finger got fairly wedged into the
weapon. When the order attention was given, Mueller could not withdraw
his finger. His predicament at once attracted notice, and he was
ordered to the front to be reprimanded by the major, to the no small
amusement of his comrades, who laughed heartily at his ridiculous
predicament. He was sent to his quarters in disgrace and the
regimental surgeon had no little trouble in liberating the thickly
swollen finger.
While everything thus seemed to promise a life of experimentation,
Mueller's imagination had a powerful hold on him, and he gave himself
up for some time to certain mystical theoretical questions and
problems of introspection which, for a time, threatened to take him
away from his real calling of an experimental physiologist.
Fortunately for Mueller, as we shall see, though at the moment he
doubtless {230} thought it a serious misfortune, these excursions into
a too introspective psychology were followed by nervous troubles, what
we could now call neurasthenia, and he was consequently led back to
the study of external nature.
Just after Mueller's promotion to the doctorate in medicine, the
Rhenish universities came once more under the authority of the
Prussian government, and Berlin became a Mecca for students, who
looked upon it in a way as the mother university. After his graduation
at Bonn, then, Mueller was attracted to Berlin, and came especially
under the influence of Rudolphi, who recognized his talents and gave
him special opportunities for original investigation. Rudolphi's
private library and his collection were placed at the command of this
young original worker, who had already proved his power of
investigation and his capacity for following a subject to its ultimate
conclusions, even though those were not yet extrinsically known. While
at Berlin, too, Mueller came under the influence of the younger Meckel,
whom he learned to respect very much. After Meckel's death the
_Archives of Physiology_, previously edited by Meckel, fell into
Mueller's hands, who successfully continued it for many years.
At Mueller's departure from Berlin he was presented by Rudolphi with an
English microscope, as a testimonial of the old professor's
appreciation of the young man's labors while under his observation. As
Mueller's pecuniary resources were very limited, this must have been an
especially acceptable gift, since it enabled him to continue his
researches in embryology, and it was not long before these began to
bear fruit. At Bonn, to which Mueller returned, he set up as a
Privat-Docent in the University, and for several years eked out by
teaching the allowance his mother could give him, and even by the
practice of medicine.
Bonn, at this time, had a population of perhaps 30,000, {231} and had
some eighteen regular practitioners of medicine. It is easy to
understand, then, that Mueller's practice did not add materially to his
pecuniary resources. It was not long before he gave up the practice of
medicine entirely, led to the step by the sad death of a friend, who,
while under his care, suffered from perforation of the intestines,
followed by peritonitis. Notwithstanding the rather precarious state
of his finances, at the age of twenty-six, Mueller married Anna Zeiler,
the daughter of a landholder in the Rhineland, not far from Bonn. He
had previously dedicated to her a poem, in which he promised her, in
lieu of more material advantages as a marriage settlement, an immortal
name. The young man seems to have felt something of the genius that
was in him, but, then, so have others, and their presages have not
always been confirmed by the issue. Shortly before and after his
marriage, he applied himself so hard to his investigations of many
kinds that within a few months he broke down. The government allowed
him a furlough, and for several months he wandered with his bride
along the Rhine, in what has been described by a biographer as a
"one-horse shay," and came back to his work renewed in mind and body.
As a matter of fact, Mueller's breakdown was what would be called at
the present time a neurasthenic attack, induced by overwork and too
great introspection. He had been experimenting upon himself in many
apparently harmless ways, but by methods which often cause serious
trouble. It was not an unusual thing for him to fast, in order to note
the physiological effect on his mind and senses of the absence of
proper nutrition. He would often lie awake for hours at night in the
darkness, experimenting upon himself and noting the phenomena induced,
especially in his sight, by the total absence of light. He devoted
himself, too, to the investigation of the curiosities of second sight;
those interesting {232} reminders of things seen long ago, though
without producing much impression, and which recur at unexpected
moments, to make us think that we are seeing again when we are really
only unconsciously remembering. He used to exercise a good deal the
faculty of bringing up objects into his vision with all the physical
peculiarities of actual sight. In this his master was Goethe, who had
written extensively on this subject in treating of the phenomena of
vision, and who was able himself to recall to his imagination with
great vividness the many shades of colors of objects with the sensory
satisfaction of actual vision. Mueller had this imaginative power only
for the reds.
It is not surprising that a young man, engaged too exclusively at this
sort of investigation, should have impaired his nervous equilibrium to
some degree, and made symptoms, otherwise unimportant, appear to him
as the index of serious illness. For a time Mueller despaired of ever
being himself again. When he had regained his health, however, he
realized what had been the essential cause of his nervous condition;
and so he never went back to his introspective observations,
considering their results somewhat in the nature of a series of
illusions.
After this, Mueller devoted himself for ten years strictly to his
physiological investigations. The best knowledge of what Mueller
accomplished for scientific medicine, during these early years, can be
obtained from Virchow's summation of the discoveries of this period
made shortly after his great teacher's death.
Virchow says:
"It was Mueller who introduced to the knowledge of physiologists and
physicians the doctrine of reflex actions, which had been already
indicated by Prochaska, and simultaneously discovered by Marshall
Hall and himself. Just before this Mueller succeeded in showing an
{233} easy mode of performing experiments on the anterior and
posterior roots of the spinal nerve in corroboration of Bell's
teaching of their diverse functions. Thus he had the privilege of
establishing for all time two of the greatest practical discoveries
of the physiology of the nervous system.
"Next to the nerves the blood became the subject of his researches
and he not only naturalized in German medicine the accurate
knowledge of the fibrin and blood-corpuscles, which Hewson had
cultivated with such fertility in English literature, but he also
managed by simple experiment to demonstrate the peculiar composition
of the vital fluid. The discernment of right methods of
investigation lay ever open to his clear and cultivated intellect,
and he knew well that there were cases in which the scalpel and
experiments could not determine a question, and where the truth was
only to be elicited by means of chemical agents and physical
instruments. It was thus he discovered the peculiar gelatinous
substance found in cartilage, called chondrin; thus he proved the
existence of lymphatic hearts in the amphibia, and thus that he
determined not only the organs but all the laws which are concerned
in the production of the human voice.
"The special researches of the Bonn epoch are those of the minute
structure and anatomy of the glands. They put an end to the
controversy which had existed so long between adherents of Malpighi
and Ruysch, concerning the sacculated extremities of the glandular
follicles, and obtained for us a correct knowledge of these
important organs throughout the whole animal kingdom. Perhaps his
most important work is that of the Ducts of Mueller, the structures
(named after him) which form so important a part of the
genito-urinary system in the embryo."
Practically all this had been accomplished before he was {234} quite
thirty-two years of age. In the autumn of 1832, Rudolphi, the
professor of physiology at Berlin, died. As Virchow says, candidates
sprung up on every side, and some who were the least qualified
considered themselves best fitted for the position. Mueller took an
unusual step which illustrated his decision in character, though in
any other it would have seemed an evidence of conceit. He declared, in
an open letter, laid before the Minister of Prussia, that his claims
were superior to those of any other living physiologist, except John
Frederick Meckel. So powerful was the impression produced upon the
minister by this letter that he immediately appointed Mueller to the
vacant chair.
Not long after his appointment to the chair of physiology at the
University of Berlin Mueller completed the well-known "Hand-book of
Physiology," which established his reputation. The book is sometimes
spoken of as an experimental physiology, but this is not correct.
Mueller was no more a mere experimentalist than Haller, and he,
himself, heartily detested the tendency which experimental physiology
had assumed in France, especially under the influence of Magendie.
Part of Mueller's aversion to experimental physiology was aesthetic. He
could not bear the idea of inflicting so much pain as many of his
colleagues inflicted without a thought. In his panegyric of Rudolphi,
Mueller says: "Rudolphi looked upon physiological experiments as having
no relation to anatomical accuracy, and it is no wonder that this
admirable man, who had at every opportunity expressed his abhorrence
of vivisection, took up a hostile position against all hypotheses and
conclusions insufficiently established upon physiological
experiments." Mueller adds: "We could not have failed to share his
righteous indignation, had we seen how many physiologists were using
every effort to reduce physiology to an experimental science by the
live dissection and agonies {235} of innumerable animals, undertaken
without any definite plan, and yielding often only insignificant and
imperfect results."
Mueller shared these views of Rudolphi with regard to vivisection. The
uncertainty of the conclusions, the amount of suffering inflicted, and
the indefiniteness of the conditions of experiment, so that the
conclusions could not have any very great weight, or any special
accuracy of information, made him consider such experiments, unless
very carefully conducted by trained investigators, as largely a waste
of time and infliction of unnecessary pain and a leading astray of
physiological advance because of the uncertainty involved.
The qualities in Mueller's "Hand-book of Physiology," which gave it its
greatest value, are the thorough review of all of the physiological
literature of the world which it contains, and the greatest number of
original observations it details as the basis of the principles
enunciated. Mueller himself said, in the preface to his "Hand-book": "I
need scarcely remark that it is the duty of a scholar to make himself
acquainted with the progress of science among all nations; and this is
now possible and, moreover, quite indispensable in these days of
progress. A purely German, French, or English school of medical
science is barbarism; and in Germany we would consider the idea of an
isolated English or French system of natural history, physiology or
medicine just as barbarous as the notion of Prussian, Bavarian, or
Austrian medicine or physiology."
How valuable the book was as the corner-stone of modern German
medicine, may best be judged from Virchow's opinion of it. He says in
his panegyric of Mueller:
"There are two qualities in his 'Hand-book of Physiology' which have
particularly enhanced my estimation of its value--its strictly
philosophical method and its completeness {236} in facts. Since the
time of Haller no one has so thoroughly mastered the entire
literature of natural history or collected in all directions so many
original experiences, and no one has been at the same time familiar
with medical practice, as well as with the remotest provinces of
zoology. It has been well said that while Haller often, in doubtful
questions, espoused a side which must eventually be forced to
succumb, Mueller always had the luck (if we may call that luck which
was preceded by so much intelligent activity), sooner or later, to
discern the opinion that was sure, eventually, of the victory. He
was wonderfully fitted for the office of critic by his comprehensive
knowledge. He knew how to discriminate the healthy from the unsound,
the essential or real from the adventitious or accidental. And, in
surveying the whole series of forms--often widely different--among
which a well-determined plan of nature seemed to be realized, he
knew the changes which not infrequently altered considerably the
arrangement and composition of the substances within these forms. In
Mueller, as a physiologist, it is not the genius of the discoverer,
nor the ground-breaking nature of his observations we admire, but
rather the methodical exactness of investigation in calculating
judgment, the confident tranquility and the perfect consummation of
his knowledge."
In a word, Mueller owed the success of his career to the perfect poise
of his intellect and the admirable critical faculty that guided him in
the thorny path of knowledge at a time when there were so few
landmarks of real scientific significance to show the investigator
what the probable course and progress of real science must be. It was
for this reason that, as Virchow has said, the reform of newer views
became embodied in him, and in spite of the almost monastical
retirement of the scholar, the influence of the method introduced by
Mueller was not limited to physiology, but continues to {237} spread
beyond that science in ever-widening circles into the domain of all
the biological sciences.
Virchow concludes: "Mueller vanquished mysticism and phantasms in the
organic kingdom and he was most distinctly opposed to every dangerous
tendency, whether it was pursued under the pretext of physiology or
belief, or merely in accordance with conjectures. Mueller did not
discover, but he firmly established the exact method of investigating
natural sciences: Hence, he did not found a school in the sense of
dogmas--for he taught none, but only in the sense of methods. The
school of natural science which Mueller created knew no community of
doctrine, but only of facts and still more of methods."
He did not confine himself in his studies, however, to the physiology
and pathology, nor even to the anatomy and embryology of man. After
1840 he devoted himself to the study of invertebrates and investigated
the starfish and the pentacrinites. While engaged in his work on the
invertebrates he found that the fossil remains of animals had not been
carefully explored, so for a time he devoted himself to paleontology.
While his salary as professor was ample for his own support, it was
not what would be called generous at the present time, yet Mueller
became so devoted to his science that he paid certain of the workmen
to be on the lookout for fossil remains for him in the quarries of the
Eifel. He became deeply interested, too, in life in the sea and made
his vacations times of specially hard work, investigating the
conditions of low life among marine organisms. He passed from one
class of life to another. From sea-urchins and starfish to infusoria
and polycystina, whose varieties he was himself the first to recognize
and describe.
Mueller was one of the first to point out that certain of the lower
animals could propagate similar and dissimilar {238} generations, that
is, reproduce by alternate generations. He studied and demonstrated
especially the metamorphoses in the echinodermata, and his broad
vision and careful observation in this new and surprising scientific
field cleared up many things that had been mysteries before.
In paleontology Mueller worked with our own Agassiz, then a young man,
or perhaps it should rather be said that Agassiz worked with Mueller. A
paper, for whose compilation they made a series of observations
together, appeared at Neufchatel, in 1834. It was a note on the
vertebrae of living and fossil dog fishes. At this time Mueller was
interested in fossil fishes of many kinds and wrote several articles
in later years on this subject. Toward the end of Mueller's life he
studied especially the polycystina, certain of the radiolaria, and
some of the many chambered specimens, fossil and living, that were
attracting much attention at that time. As a matter of fact he went
the day before his death to the zoological museum of Professor Peters
in Berlin, in order to obtain some polythalamacea.
How open to advance in science and how ready to encourage the work of
others Mueller was, may be gathered from his attitude to parasites as
the cause of disease, when these began to be discovered. After
Professor Schoenlien's discovery of the parasite of favus, Mueller
became interested in it, confirmed Schoenlein's observations and added
something to our knowledge of it. About this time, also, he discovered
the psorosperm as a parasite of animals and possibly of man, and
devoted considerable attention to it. His work was afterward greatly
extended by one of his pupils, Lieberkuehn, whose researches with
regard to these minute organisms attracted the attention of the
medical world.
It is not a little surprising how many of the investigations that
afterward were to give fame to Virchow were initiated {239} by his
great teacher, Mueller. It was Mueller whose study of tumors led Virchow
to devote himself to this subject and give us the best pathological
work on it that has ever been written. Virchow himself notes with
regret that Mueller turned aside from pathology and never finished the
promised work which was to have contained his theory of the origin of
tumors. Another work in which Virchow followed in Mueller's footsteps
was the development of craniometry and, in general, the scientific
investigations of skulls. Mueller had interested himself very much in
microcephalic skulls and Virchow assisted him in the investigations of
them. Many years afterward Virchow established the science of
craniology in the department of anthropology, and succeeded in
throwing not a little light on the origins of races by his discoveries
in this matter.
After Schoenlien's discovery of the parasite of favus, Mueller became
interested in the parasitology of human beings, and with Retzius, the
famous Swedish anatomist, investigated certain molds which occur in
the respiratory passages of birds. They succeeded in demonstrating
that these vegetable parasitic growths were a form of Aspergillus.
Their studies in the white owl particularly called general attention
to the possibility of such molds occurring as parasites of animals.
Later on, Virchow showed that these same molds occur occasionally in
the respiratory passages of men. Virchow found them in three bodies at
autopsy, all of them being run down individuals, two of them old
subjects, and all sufferers from chronic bronchitis. Usually, when the
parasites were found, there was a distinct tendency to very low
resistive vitality in the tissues, sometimes proceeding even to the
extent of beginning pulmonary gangrene. In reviewing the subject
Virchow [Footnote 7] said that the light thrown {240} upon it by the
investigations of Mueller and Retzius was of the greatest possible
assistance in enabling him to identify the parasite when he found it
in human subjects.
[Footnote 7: Virchow's Archiv, Bd. ix.]
The number of positive facts which Mueller brought to light in the most
diverse departments of science is almost beyond calculation, and yet
it is astonishing how seldom the slightest error, or even an
incomplete observation, can be found in his work. On the other hand,
it has happened, over and over again, that when the correctness of his
observations in the beginning seemed according to other investigators
to be dubious, they have come eventually to be acknowledged as
representing the truth. As a rule, he went over every set of
observations three times. During the second series he wrote about
them. He always repeated the experiments on which his observations
were founded while his material was going through the press. His
manuscripts were a mass of corrections; notwithstanding this, his
proof sheets were the despair of the printers.
Mueller accomplished all this only by the most careful husbanding of
his time. He knew how to make use even of the ends of hours and brief
intervals which others waste without a thought about them. He used to
call these periods of short duration between the duties "the gold-dust
of time," and said that he did not wish to lose a particle of it. In
the quarter of an hour between two lectures it was not an unusual
thing to find that he took up some dissection at which he was engaged,
or continued his work sketching the observations that he had been
making during the previous day.
How thorough was Mueller's work in everything that he devoted himself
to can be gathered from certain excursions into pathology, which was,
after all, only a side issue in his work, and to which he gave very
little serious attention. Mueller's assistant in the Museum of Berlin,
and one of his {241} favorite pupils, Schwann, made a series of what
Virchow calls comprehensive and magnificent investigations on the cell
structures of the animal tissues, on which progress in pathology so
essentially depends. Mueller followed up these discoveries, and, to
quote Virchow once more, he was in this matter the authority of
authorities; for the medical world owes to him practically all its
knowledge of tumors. Mueller first demonstrated the harmony which
existed between the pathological and the embryonic development of
tumors.
This physiological observation is of the highest importance. It came
at a time when tumors were considered to have nothing of the
physiological about them, but to be entirely manifestations of morbid
processes foreign to all natural functions of the body. Mueller's
observation of the identity of the pathological and the embryonic
development of tumors is really the key to the whole doctrine of
morbid formations. Virchow assures us that Mueller's labors gave the
strongest impulse to the employment of the microscope in pathological
investigations. Undoubtedly this was his most important contribution
to scientific medicine. With this he laid the foundation of the
explanations of tumors--a work that his great pupil was destined to
carry on. Some of Mueller's work in this line, his study of
enchondromata for instance, Virchow confesses to have been part of the
inspiration that led to his own later work. Mueller was occupied,
however, with too many things to devote himself to the study of
pathology in the way that would have been necessary to make great
discoveries in the science. He promised that he would sometime settle
down to make a classification of tumors, and that the principle of
such a classification would not be based either on their fineness of
structure or on their chemical composition, but that their
physiological nature and tendency to grow must be taken into account.
When he died, however, he {242} left behind him nothing unfinished
except the long-expected conclusion of his book on tumors.
Mueller's most important work in physiology, and his most far-reaching
influence on the biological sciences, which were just then beginning
their modern development, came from his assertion of vital force as a
thing entirely different from and absolutely independent of the
physical or chemical forces which it directs and makes use of. Vital
force for Mueller was the ultimate cause and supreme ruler of vital
phenomena, so that all the energies of an organism follow a definite
plan. It was for him the complete explanation of all the physical
manifestations of life. It disappears in death without producing any
corresponding effect. Without losing anything of itself it hands over
in multiplication or reproduction a force equal to itself to the new
being that is born from it. This vital force that is thus handed over
need not necessarily manifest itself at once, but may lie dormant for
a long time to be awakened to manifestations of life by the
concurrence of proper conditions in its environment.
In a word, Mueller appreciated fully the mystery of life, faced the
problem of it directly, stated it in unequivocal terms, and by so
doing saved the rising science of biology from wandering off into
speculations which were seductive enough at that time, but which would
have proved vain and wasteful of time and investigative energy.
Mueller's influence on his students was sufficient in this matter to
set the seal of vitalism, as it is called, on most of the biological
work done in Germany about the middle of the century, and it was a
recurrence to his observations and his methods which led the reaction
to vitalistic theories that characterized the concluding years of the
nineteenth century.
With regard to the significance of Mueller's work, Professor Du
Bois-Reymond, himself a pupil of Mueller, in his memorial {243} address
delivered before the Royal Academy of Sciences of Berlin in 1859,
[Footnote 8] says: "It has been objected by those who insist on the
greatness of Mueller's reputation that he himself made no discovery
that can be said to be of the first rank. Mueller's fame is great
enough for us to allow that there is something true in this objection.
He accomplished more in developing the ideas of others than in
original research of his own. That he did not make any great discovery
is, however, rather due to the fact that he came at a time when great
discoveries were no longer lying around loose as they had been in the
preceding century, waiting to be made, as it were; and what he
accomplished was of more value than one or two single discoveries of
primary importance. He made the original ideas of other men so clear
that they were at once accepted by all the medical and scientific
world. In this way he furthered the progress of medicine better than
any devotion, however successful, to one single feature could possibly
have accomplished.
[Footnote 8: Gedaechtnissrede auf Johannes Mueller, von Emil Du
Bois-Reymond, Berlin, Buckdruckerei der Koeniglichen Akademie der
Wissenschaften (Dummler), 1860.]
"Mueller made mistakes, but then who ever fails to make mistakes in the
face of nature? As a rule, however, he hit the nail on the head. There
are many suggestive thoughts from him that the investigators of later
times have proved to be true. He suggested, for instance, that there
must necessarily be some connection between the ganglionic bodies and
the nerve stems. He suggested, also, that there must be a special
nerve system for the intestinal tract. Later discoveries in physiology
have established both of these thoughts and have shown that Mueller had
so entered into the spirit of nature and her processes as to be able
to think her thoughts. There is no doubt that there are suggestions in
{244} his writings, especially those of the later years of his life,
which will give a series of triumphal substantiations of the same
kind."
Du Bois-Reymond's final judgment is of special interest, because it
tries to point out the comparative place that will be occupied by
three great men in the biological sciences of a century ago:
"Haller and Mueller must be considered as giants of earlier days,
though when future generations compare them with Cuvier they will
occupy somewhat of the position that Galileo and Newton hold in
comparison to La Place and Gauss, or Lavoisier in comparison to
Berzelius. The first of these men had the opportunity to do great
things while it was yet possible to do them, and left to their
successors only the possibility of developing their thoughts."
[Footnote 9]
[Footnote 9: Some idea of the estimation in which Mueller was held
by his contemporaries, German and foreign, may be gathered from
the number of scientific bodies of which he was a member. He was
an associate in practically every serious scientific body in
Germany. He was, besides, foreign member of the scientific
academies at Stockholm, Munich, Brussels, Amsterdam; the
scientific societies of Goettingen, London, Edinburgh, Copenhagen;
foreign honorary member of the Academy of Sciences of Vienna;
corresponding member of the Academies of St. Petersburg, Turin,
Bologna, Paris and Messina; of the Society for Science at Upsala,
of the Mecklenburg Naturalist Society of Rostock, of the
Senkenberg Institute of Frankfort-on-Main, of the Academy of
Natural Sciences of Philadelphia, of the Society of the Museum of
Natural History at Strasbourg, of the Naturalists' Association of
Dutch East India; member of the Holland Society of Sciences,
Haarlem; of the Naturalist Society of Frieburg in Breisgau, Halle,
Dantzig and Mainz; of the American Philosophical Society of
Philadelphia, of the Society of Biology of Paris; honorary member
of the Cambridge Philosophical Society, of the Natural Science
Union of Hamburg, and the Natural Science Association of the
Prussian Rheinland and Westphalia, of the American Academy of Arts
and Sciences in Boston, of the Ethnological Society of London, of
the Microscopic Association of Giessan, member of the Society for
Science and Medicine at Heidelburg, of the Naturalists' Society at
Dresden; corresponding member of the Scientific and Medical
Association of Erlangen and Moscow; member of the Academy of
Medicine of Paris; honorary member of the Academy of Medicine of
Prague and of Dorpat, of the Medico-Chirurgical Academies of Wilna
and of St. Petersburg, of the Medical Society of Guy's Hospital in
London, of the Medical Society of Edinburgh and of the Hunterian
Society of the same city, and of the Medico-Chirurgical Societies
of London and of Zurich, of the Medical Societies of Budapest, of
Lisbon, of Algiers and Constantinople; corresponding member of the
Medico-Chirurgical Academy of Turin and of the Medical Society of
Vienna.
Even this long list does not include all his various honorary and
active memberships in scientific and medical societies. He was,
besides, the laureate, that is, a prize winner, of the Medical
Faculty of the University of Bonn, of the Soemmering Prize of the
Senkenberg Institution, of the Copley Medal of the Royal Society
of London, of the Culver Prize Monthyon of the same institution,
as well as laureate of the Academy of Sciences of Vienna for
Experimental Physiology. He had been honored by the King of
Prussia by the conferment of the knighthood of the Order of the
Red Eagle, by the King of Sweden by the Royal Swedish Order of the
North Star, by the King of Bavaria by the Royal Bavarian
Maximilian Order, and by the King of Sardinia by a knighthood in
the Order of SS. Mauritius and Lazarus.]
{245}
It is as a teacher that Mueller did his best work. He was not by nature
a good talker and never said much, but he was very direct; and, as he
spoke from the largest possible and most progressive knowledge of the
subject, his lectures were always interesting to serious students.
There seems to be a more or less general agreement that for the mass
of his students he was uninteresting because likely to be above their
heads. For the talented members of his class, however, he was an ideal
teacher--always suggestive, always to the point, and eminently
complete. Du Bois-Reymond says that he never was confused, never
repeated himself, and never contradicted himself.
He was able to illustrate his lectures by sketches on the board in a
way that enabled students to follow every step of {246} even a
complex, embryological developmental process. He could trace, step by
step, with the chalk, every stage of evolution in the organism and
bring it clearly before his students. To a narrow circle of the best
men within his class he became a personal friend, whose inspiration
led them on to the deepest original researches. Among his students
were some of the men who made German medicine and German science known
all over the world in the last fifty years. Chief among them may be
mentioned Virchow, Helmholtz, Du Bois-Reymond, Schwann, Lieberkuhn,
the discoverer of the follicles in the intestines; Max Schultze, whose
work in histology and physiology are well known; Claparede, Remak,
Guido, Wagener, Lachmann and Reichert.
What he demanded of his students above all was that they should learn
to help themselves. He set them tasks, gave them suggestions, directed
their work, corrected their errors, but he wanted them to do work for
themselves. His very presence was an inspiration. Both Virchow and Du
Bois-Reymond speak of the power of his eye. Du Bois-Reymond says that
there was in him an almost demoniac magic, and that students looked to
him as the soldiers of the first Napoleon did when the great Emperor's
words were in their ears--"Soldiers, the Emperor has his eye on you."
Du Bois-Reymond adds that, consciously or unconsciously, every student
felt the winning influence of his great personality. With all this he
knew how to unbend, especially with favorite students, and many a joke
from him found its way around the laboratory even during working
hours. He was not one to stand on his dignity, and Virchow tells of
him that even when nearly fifty he was known to race with a student
down the corridor from one class-room door to another. He took up
skating at the age of forty-five, and though he had not many friends
and was too entirely devoted to his work to make {247} many
acquaintances, it was always a source of pleasure to young men to be
allowed to associate with him, and many eagerly sought the privilege.
How impressive a figure Mueller made in his character of teacher can be
gathered best, perhaps, from a note added to Virchow's panegyric
during its progress through the press, in which the pupil tells his
impressions of the master:
"I must confess that Mueller, in his lectures and in his manner,
reminded me of a Catholic priest, which might be accounted for by
the impressions of his early childhood. When as the dean of the
Faculty he mounted the _cathedra superior_, dressed in his official
robes, and pronounced the Latin formulary of the proclamation of the
doctors of medicine, with short, broken and contracted words; when
he began his ordinary lectures in almost murmured syllables; or,
when with religious earnestness he was discussing any of the
abstruse questions of physiology, his tone and manner, his gestures
and looks, all betrayed the traditional training of the Catholic
priest."
Virchow adds, "Mueller himself was what he styled one of his greatest
predecessors--perpetually a priest of nature. The religion which he
served attached his pupils to him as it were by a sacred bond; and the
earnest, priest-like manner of his speech and gestures completed the
feeling of veneration with which everyone regarded him."
In the recently issued life of von Helmholtz, the great German
physicist, his biographer makes it very clear how much Helmholtz
thought of Mueller, one of the earliest teachers. [Footnote 10]
Helmholtz, Bruecke, and Du Bois-Reymond were warm personal friends
(college chums we would call them in America), and all fervent
admirers of their greatest {248} master, who showed them, as Helmholtz
says, "how thoughts arise in the brains of independent thinkers." A
half-century later, in his recollections of the time, he said: "He who
has come in contact with one or more men of the first rank has his
mental intellectual standard for all time broadened, and such contact
is the most interesting thing that life can hold." Curiously enough,
one of the most interesting things in Helmholtz's recollections is
that, despite the fact that the poverty of his parents made it
advisable for him to get through his medical studies as soon as
possible, Mueller persuaded him to take another year's medical work
before going up for his graduation. This was mainly for the purpose of
having his pupil complete an essay in physiology on which he was
engaged. Mueller offered him the use of his own laboratory and all his
instruments for this purpose. His judgment was justified by
Helmholtz's wonderful work on the conservation of energy made within a
few years after his graduation.
[Footnote 10: Herman von Helmholtz, von Leo Koenigsberger. Bd. 2,
Braunschweig, Friedrich Viewig und Sohn, 1902-3]
Mueller's death was sudden, though not entirely unexpected. He had been
ailing for many months and had resolved to give up his lectureship. He
had made most of his preparations for settling up his affairs, and had
even sent for his son, who was practising medicine at Cologne, to come
up to see him. He made a special engagement for a consultation with
his physician for a certain morning, and having gone to bed in
reasonably good spirits, in fact, feeling better than he had for a
long while, was found dead in the morning. Some time before he had
made his will forbidding an autopsy, and so the exact cause of death
will never be known, though it is rather easy to surmise that it was
due to apoplexy, as arteriosclerosis--that is, degeneration of
arteries--had been noticeable in Mueller for some years, and his
temporal artery particularly had become hard and tortuous.
Mueller was buried with all the rites of the Church, and as {249} in
Germany the ecclesiastical authorities are very strict in this matter,
there can be no doubt that the great physiologist had been a faithful
Catholic. He was known for his edifying attendance at Mass on all the
Sundays of the year. Many years afterward, in the midst of the
Kulturkampf in the early seventies, a monument was erected to him in
his native Coblentz, and the occasion of its unveiling was taken by
the Catholic Rhineland for a celebration in honor of their great
scientist.
For a time, in his younger years, Mueller appears to have been not all
unaffected by the materialistic tendencies so rife in the science of
the time. His early anatomical investigations seem to have clouded
somewhat his faith in things spiritual. One of the expressions
attributed to him before his twenty-fifth year is that nothing exists
in the human being which cannot be discovered by the scalpel. It was
not long, however, before Mueller repudiated this expression and came
back to a realization of the importance of the immaterial. Another
expression attributed to him, "Nemo psychologus, nisi physiologus,"
"No one can be a psychologist, unless he is a physiologist," has been
often repeated as if Mueller meant it in an entirely materialist sense.
As a matter of fact, however, it is intended to convey only the idea
that no one can really exhaust the science of psychology unless he
knows the physiology of the brain, the organ which the mind uses in
its functions in this life. The expression is really the foundation of
the modern physiological psychology, which is by no means necessarily
materialistic in its tendency, and has become a favorite subject of
study even with those who appreciate thoroughly the importance of the
immaterial side of psychology.
Mueller seems never to have gotten so far away from the Church as that
other great physiologist of the succeeding generation in France,
Claude Bernard, who for many years allowed himself to be swamped by
the wave of materialism {250} so likely to seem irresistible to a
scientist engaged in physiological researches. But, even Claude
Bernard came back to the Church before the end, and, under the
guidance of the great Dominican, Pere Didon, reached the realization
that the only peace in the midst of the mysterious problem of life and
the question of a hereafter is to be found in a submissive faith of
the doctrines of Christianity.
Many years ago, when Virchow took it upon himself to say harsh words
in public of Catholic scholarship, and to put forward the hampering
influence of the Church on intellectual development as a reason for
not allowing Catholics to have any weight in educational matters, the
organ of the Catholics of Germany, _Germania_, reminded him that his
own teacher, the great Johann Mueller, the acknowledged father of
modern German medicine, and the founder of the fecund scientific
method to which so many discoveries in the biological and medical
sciences are due, had been brought up and educated a Catholic, had
lived all the years of his productive scholarship and fruitful
investigation in her bosom, and had died as an acknowledged son of the
great mother Church.
Mueller is certainly one of the great names of nineteenth century
science. When many another that seems now as well, or perhaps even
better known, shall have been lost, his will endure, for his original
researches represent the primal step in the great movement that has
made possible the advances in nineteenth century medicine. He was
honored by his contemporaries, venerated by the men of science who
succeeded him; he has been enshrined in a niche for himself by
posterity, and his name will remain as that of one of the great
geniuses to whose inventive faculty the world owes some of those steps
across the borderland into the hitherto unknown which seem so obvious
once made, yet require a master mind to make and mean so much for
human progress.
{251}