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THE LIFE WORKS of some men seem to have been specially designed as vehicles by which
bits of wisdom of the Infinite may be conveyed to waiting mankind. Among those so
selected must have been Louis Pasteur. “By the design of his life,’’
wrote Stephen Paged, “he was always being led straight . . . from each discovery
to the next . . . he taught the whole world a new way of thinking of the infective
disease, and a new way of dealing with them.’’ Not only had Pasteur
the ability to discover new facts: he knew how to adapt his findings to practical
applications, and how to teach and inspire others. His discoveries live on in the
works of man who came after him. By the middle of the nineteenth century, medical
men knew but little more than had their Greek forebears about actual causes of the
great scourges of the race-the plagues, the fevers, and the pestilences. At the
close of the century, at the end, of Pasteur’s career, the germ theory had
been proved and no longer was seriously contested; the patterns of many infective
disease were understood; methods had been devised for preventing or for combating
some of the most serious infections; conditions under which surgical procedures
were carried out had been revolutionized; and the sciences of bacteriology and of
preventive medicine had been launched. Indeed, within few life spans have such revolutions
taken place in medicine; and he who had brought them about was not a physician,
but a chemist. His laboratories were not spacious expanses of glass and steel, but
miserable garrets; he had not a background of wealth and means, but was the son
of a poor tanner. Louis Pasteur was born December 27, 1822, to Jean-Joseph Pasteur
and his life, Jeanne-Etiennette, in a very modest hone adjacent to a tannery, in
Dile, Department of Jura, and France. He grew up in nearby Arbois, in which city
his father set up a tannery in 1827. Louis’ preliminary education was in schools
in Arbois, and his early inclinations were toward art-as in borne out by his youthful
paintings of his mother, of his father, and of neighbors. Lousi attended the Royal
College of Besancon, from which he received his baccalaureates in science in 1842,
ironically with a grade of “mediocre” in chemistry. His eyes set upon
the goal of the Ecoloe Normale, Pasteur went to Paris in the fall of 1842, where
he tutored to finance his studies until he passed examinations admitting him to
the Ecole Normale, Pasteur went to Paris in the fall of 1842, where he tutored to
finance is studies until he passed examinations admitting him to the Ecole Normale
in October, 1843. Pasteur was appointed assistant to the chemist A.J. Balard at
the Ecole Normale, in 1946, and attended courses given by Jean-Baptiste Dumas, then
France’s most celebrated chemist, at the Sorbonne. In 1847, Pasteur passed
his tests in chemistry and in physics, and developed interest in crystallography.
The year 1848 proved to be fateful for Louis Pasteur; he participated in the revolution
of that tear. Peace restored, he returned to his study of crystals, and in his twenty-sixth
year, achieved his first claim to scientific fame by presenting to the Academy of
Sciences his Report on the Relationship between the Crystalline Form, the Chemical
Composition, and the Direction of Rotatory Polarization. Therein he reported having
found that tartaric acid crystallizes in two chemically identical but physically
different forms, and that these right-faceted and left-faceted crystals in solution
consistently rotate rays passing through a polarimeter to the right, or to the left,
in accordance with their physical character. Met with skepticism, Pasteur won attention
and friendship from leading French scientists, including Jean-Baptiste Biot, when
at their insistence he presented them with carefully worked out proof. The joy of
this initial triumph was marred for Pasteur by the sudden death of his mother.
In September, 1848, Pasteur was appointed Professor pf Physics at the lyceum (High
school) in Dijon, but in December he was offered a collegiate position as Assistant
Professor Chemistry at the Faculty of Sciences in Strasbourg. There he could continue
his researches on crystals. There, too, he married, may19, 1849, Marie Laruent,
daughter of Rector of the college. Marie Pasteur proved to be just the type of wife
the scientist needed-she was tolerant of his devotion to research, assisted him
with his notes and his records, and looked after his physical well during an active
and hectic career.
Pasteur’s teaching career progressed. He was made full Professor off Chemistry
at Strasbourg in 1852, and in 1854 he was appointed to the Chair of Chemistry of
the Faculty of sciences in Lille, as well as Dean of the University. His work and
crystals had launched a new branch of science, stereochemistry; and in Lille, in
the heart of the sugar beet country, Pasteur began his studies on fermentation of
sugar to form alcohol. Thus did Pasteur, the chemist, begin transformation to Pasteur,
the microbiologist? With the help of his microscope Pasteur found the microorganisms
were responsible for alcoholic fermentation; and that faulty fermentation resulted
from contamination by unwanted types of organisms.
In October, 1857, Pasteur returned to Pairs, having accepted appointments as Administrator
of the Ecole Normale abd as Director of Scientific Department of the College. There
he sought a place for a LABORATORY. The Only space available was two small rooms
in an attic, dark, unsuitable, hot in summer, cold in winter. Nevertheless, Pasteur
made the best of them and was able to continue his research. A year later, he moved
to a slightly better suite of five narrow rooms. Hid incubator, installed under
a stairway, could be approached only on his knees. Finances for laboratory operation
came largely from Pasteur’s own pocket. However, as his associate, Emile Ducal,
said in later years, “From this wretched garret, which nowadays would hardly
be considered fit for a rabbit’s cage, radiated the movement that has revolutionized,
all aspects of science.” In these laboratories Pasteur continued his studies
on fermentation, culmination in a paper before the Academy of Sciences in 1859.
From alcoholic fermentation Pasteur processed to study lactic fermentation; then
to butyric microoganisma. Fermentation studies in these laboratories at the Ecole
Normale let to Pasteur’s greatest and most revolutionary contributions to
science-study and refutation of the theory of spontaneous generation, undisputable
proof of their specificity in causing disease. These studies began in 1860.
Pasteur began with study of atmospheric air. His microscope confirmed his belief
that germs floated in it. The next question was: Do germs enter putrescible substances
due to exposure to air, or are they generated within the substance? Pasteur conducted
exhaustive experiments, in the laboratory, on mountain tops, and under every Conceivable
condition. When his flasks were heated to boiling and sealed to air, no growths
appeared. When his flasks opened, exposed, and resealed in comparative’s pure
air of mountain heights remained clear. When reopened at lower levels, growths appeared.
But Poached and other supporters of spontaneous generation dogged Pasteur with denunciation,
with derision, and with purported contrary evidence.
Pasteur’s most spectacular demonstrations were made with his swan’s
neck flasks. Broth was placed in the flask, the neck of which was heated and drawn
out to form a lazy, the swan’s neck shape. When the broth in the flask was
heated to boiling, air was forced out; on cooling, air pressure outside forced air
to re-enter the flask. Due to the lazy shape of the small tubular neck, if entering
air were permitted to flow into the flask slowly, air-borne particles would fall
by gravity to the surface of the lower curve of the neck, and, as long as the flask
was not tipped or agitated, no microbial growth occurred. If, however, the flask
were tilted until broth touched the lower curve of the neck, or, if air were drawn
in rapidly by violent agitation, growth appeared.
Pasteur summed up his findings in a treatise entitled: Organized Corpuscles Existing
in Atmosphere, for which the Academy of Sciences awarded him a prize. But, to clarify
his position and to confound his opponents, Pasteur requested that a commission
be appointed to settle the debates. Interest in the dispute had reached far beyond
the walls of the Academy, however; and on April 7, 1864, Pasteur held a symposium
on spontaneous generation, at the Sorborne, before a large audience which included
leading scientists of the day. After describing his experiments in detail, Pasteur
summed up his findings with these words:
“There is now no circumstance known in which it can be confirmed that microscopic
beings have come into the world without germs, without parents similar to themselves.
Those who maintain this view are the victims of illusions, of ill-conducted experiments,
blighted with errors that they have either been unable to perceive or unable to
avoid.” Thus was spontaneous generation laid to rest and the “germ theory’
officially introduced to science. A year later, in 1865, medicine was to receive
its first dividend from Pasteur’s work: Joseph Lister, surgeon of Glasgow,
Scotland, seeking to apply in practice Pasteur’s findings, used carbolic acid
to disinfect the wound of a compound fracture in a patient at the Glasgow Infirmary,
and introduced the era of antisepsis in surgery. Detractors were long-lived, however,
in Pasteur’s own country and elsewhere. As late as 1886, Morris Longstreth,
M.D., of Philadelphia, Pennsylvania, published a serious, 16-page dissertation “Against
the Germ Theory of Disease,” in The Therapeutic Gazette.
Important as they were, Pasteur’s experiments concerning spontaneous generation
and controversies with Pouchet did not occupy all of his time: he introduced the
autoclave to kill hardy germs and spores; he applied his growing knowledge of microbes
to problems of fermentation; in 1861, he showed Orleans vinegar manufactures how
to improve their yield. From vinegar, he turned to the study of wines. He demonstrated
that proper fermentation resulted from action of air-borne wild yeasts deposited
on ripening fruit; and that “diseases’ of wines, affecting both their
flavor and their keeping qualities, resulted from other parasitic germs either having
fallen on the fruit, or having been introduced into the vats or presses. From these
studies arose Pasteur’s suggestion that vintners might protect their product,
without injury, by heating bottled wine for several minutes at 55 C. (131 F.). Thus
was the process, now called pasteurization, introduced. Importance of its subsequent
application, in fields of public health and of food preservation, is well known.
Pasteur’s wine studies were summed up in his book, Wine and Its Maladies,
published in 1866.
Pasteur accepted a professorship at the School of Fine Arts in 1863, in addition
to his work at Ecole Normale. The triumphs of this active period of his life were
marred by deaths of his father, in 1865, and of three of his daughters: Jeanne,
in 1859; Camille, in 1865; and Cecile, in 1866. Only his son, Jean-Baptiste, born
in 1851, and his daughter, Marie-Louise, born in 1858, survived. In later years,
the son entered government service; and Marie married a young secretary, Rene Vallery-
Radot, who became Pasteur’s confidant and biographer.
In 1865, at the insistence of the French Senate, Pasteur undertook studies of two
diseases that were responsible for eliminating passage of these parasitic diseases
from one generation of worms to the next. Pasteur’s methods saved the silk
industry, not only in France, but also in Austria, in Italy, and in Asia Minor.
More troubles were in store for Pasteur. In 1867, a series of disturbing incidents
at Ecole Normale resulted in Pasteur’s is being relieved of administrative
duties. He accepted a chair at the Sorbonne, and a laboratory for physiologic chemistry
was built for him at the direction of Napoleon III. In 1868, Pasteur suffered a
stroke; which seriously threatened his life and resulted in partial paralysis of
his left arm and leg. About the time his work on silk worms was completed, in 1870,
the Franco-Prussian War broke out. Not only was Pasteur’s work disrupted;
he faced dual concern for the welfare of his country and for that of his only son,
then serving in the military. Election of Pasteur (by a margin of one vote) to membership
in the Academy of Medicine, in 1873, was a great tribute to the chemist. It brought
him into close contact with his friend, Claude Bernard. It also precipitated an
almost endless fight with official medicine.
In 1874, too, Pasteur was forced by health to give up his chair at the Sorbonne.
He also received from the National Assembly an award in the form of a life pension.
Though Pasteur already had made many important and basic discoveries, the years
1877 t0 1886 were filled with new discoveries of great significance to medicine
and to science. Studies a anthrax in livestock proved both that a aerobic spore-forming
bacterium is its cause, and that genres cause disease. Further work demonstrated
that other germs cause furunculous (boils) and puerperal (childbed) fever in new
mothers. These findings demonstrated-despite constant attacks from opponents-the
importance of measures to prevent infection and to avoid contagion. However, it
was during his work on chicken cholera, in 1879, that a laboratory “accident”
led Pasteur to discover methods of attenuating bacterial cultures, of decreasing
band of increasing their toxic attributes, at will and of taming dangerous microbes
so that they might be changed from killers to benefactors – there by to pave
the way for development of vaccines and of antitoxins.
With the collaboration of his former pupil, Emil Roux, Pasteur in 1880 began the
study of rabies (hydrophobia), a dreaded infection that always fatal to man and
to animals. Terror reigned when rabid dogs or other animals were fiscovere4d, for
it was well known that prolonged, agonized illness leading to death frequently followed
vicious biters characteristic of these animals’ attacks. Pastier set out to
see what could be done to combat rabies.
By 1884, Pasteur had not only developed a method of cachinnating dogs to render
them immune to rabies; he had also developed a vaccine against swine erysipelas,
and had supervised an expedition to Egypt to study a local outbreak of cholera.
Pasteur did not consider the rabies problem solved by vaccine alone. Inability to
discover the causative microbe (later found to be a sub-microscopic virus) handicapped
him; however, he did discover the moist virulent source of infective material: the
medulla oblongata, or lowermost portion of the brain. Also, Pasteur found that by
drying the cord aseptically, the virulence of causative factor that it drying the
cord aseptically, the virulence of the causative factor of rabies decreased to the
point of virulence in 14 days. Since the incubation decreased to the point of virulence
in 14 days. Since the incubation period (from time to bite to onset of disease)
for rabies was several weeks, Pasteur found that he could successfully treat an
animal, already bitten by a rabid animal, if treatment were began within a few days
after the injury. Treatment consisted of injecting daily ban emulsion of cord, beginning
to the least virulent material (dried for 14 days) and progressing to the most corpulent
(dried for 1 or 2 days). Thus, rabies could be prevented and lives saved. These
experiments on animals were repeated and repeated; but Pasteur hesitated to try
his method on humans.
Fate precipitated the crucial, experiment: A provincial mother appeared at the laborites
with her nine-year-old son, Joseph Meister. The boy had been bitten fourteen times,
two days before, by a dog declared rabid. The age of the child, plus the severity
of his wounds, made it seem inevitable that he would develop rabies and die. The
mother’s imploring, the family doctor’s urging, and the favorable consensus
of this scientific colleagues persuaded Pasteur to try his vaccine on the boy. A
physician began treatment, July 7, 1885-first, administering a dose of the weakest,
then progressively, doses of more virulent emulsions of infected cord. Pasteur anxiously
watched for signs of reaction; but the boy stood the test, far better than the scientist.
(In later years, Joseph Meister was to join the staff of the Pasteur Institute.)
A few weeks later, Pasteur presented to the Academy of Sciences his famous report:
Method of Preventing Rabies after a Bite. Publication of this report brought pilgrims
to his laboratory for rabies treatment-some patients coming from as far away as
New York. On March 1, 1886, Pasteur submitted to the Academy of Sciences his further
report. Of 350 persons who had received treatment following bites of rabid animals,
there had been but one death-a girl brought to him thirty-seven days after she had
been bitten by a rabid animal.
Physicians and scientists from all over the world now flocked to Pasteur’s
laboratories to learn firsthand about prophylactic treatment against rabies, and
about other Pasteurian doctrines which were rapidly revolutionizing the practice
of medicine.
The excitement and labor of this period proved too much for the ageing man: in November,
1886, he developed symptoms of coronary insufficiency. However, with the help of
Madame Pasteur and his loyal son-in-law, Rene Vallery-Radot, Pasteur was enabled
to supervise the ever-widening scope of work of his associates.
November 14, 1888, the Institute that bears his name was dedicated. The good work
went forward: Roux then developed servo-therapy for tetanus; Chalmette, serotherapy
for snake bites; and Metchinikoff established existence and action of phagocytes
in the blood, and car fried out basic studies on syphilis. Pasteur’s seventieth
birthday, December 27, 1892, was occasion for an ovation at the Sorbonne, attended
by scientists and political figures from all over the world. Lister paid the tribute:
“Pasteur has lifted the veil that for centuries has hidden the infections
diseases.’’ At the end of the ceremonies, Pasteur, too moved to speak,
asked his son to read his acknowledgment.
The great scientist’s health steadily declined, limiting him to occasional
observance of work in the laboratories and to visits from members of his devoted
staff. After a series of cerebrovascular accidents, death came to Pasteur, September
28, 1895.
The government of France arranged an imposing state funeral for its great citizen,
and Pasteur’s body was interred in a marble crypt in a small chapel within
the Institutes On its walls may be seen mosaics and plaques all duding to his work;
and most impressive is the imposing list of the areas in which Pasteur’s principal
discoveries were made: Molecular Asymmetry; Fermentations; Spontaneous Generation;
Studies On Wine; Diseases of Silkworms; Studies on Beer; Virulent Diseases; Virus
Vaccines; and Prophylaxis of Rubies.
THE PICTURE
Proof that microbes are reproduced from parent organisms, and do not result from
spontaneous generation, came from careful experiments in makeshift laboratories
of France’s famed chemist and biologist, Louis Pasteur (1822-1895), at Ecole
Normale, Paris. Behind him are portraits of his father and mother, which he painted
during his youth. Mme. Pasteur waits patiently for him to complete an observation.
From basic work begun in these laboratories came proof of the germ theory of disease,
which transformed medical practice; vaccines for virulent diseases, including anthrax
and rabies; solution of many industrial biochemical problems; and founding of the
famed Pasteur Institute.
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