SCIENCE AND WAR--PASTEUR, LISTER
In the history of science war is no mere interruption, but a great
stimulating influence, promoting directly or indirectly the liberties of
the people, calling into play the energy of artisan and manufacturer,
and increasing the demand for useful and practical studies. In the
activities of naval and military equipment and organization this
influence is obvious enough; it is no less real in the reaction from war
which impels all to turn with new zest to the arts and industries of
peace and to cherish whatever may tend to culture and civil progress.
Not infrequently war gives rise, not only to new educational ideals, but
to new institutions and to new types of institution favorable to the
advancement of science. As we have already seen, the Royal Society and
Milton's Academies owed their origin to the Great Rebellion. Similarly
the Ecole Polytechnique, mother of many scientific discoveries, rose in
answer to the needs of the French Revolution. No less noteworthy was the
reconstruction of education under the practical genius of Napoleon I,
the division of France into académies, the founding of the lycées, the
reëstablishment of the great Ecole Normale, and the organization of the
Imperial University with new science courses and new provincial
Faculties at Rennes, Lille, and elsewhere. With all these different
forms in which the influence of war makes itself felt in the progress of
science the life and career of Louis Pasteur (1822-1895), the founder
of bacteriology, stood intimately associated.
He was born at Dôle, but the family a few years later settled at Arbois.
For three generations the Pasteurs had been tanners in the Jura, and
they naturally adhered to that portion of the population which hailed
the Revolution as a deliverance. The great-grandfather was the first
freeman of Pasteur's forbears, having purchased with money his
emancipation from serfdom. The father in 1811, at the age of twenty, was
one of Napoleon's conscripts, and in 1814 received from the Emperor, for
valor and fidelity, the Cross of the Legion of Honor. The directness and
endurance of the influence of this trained veteran on his gifted son a
hundred fine incidents attest. In 1848--year of revolt in the monarchies
of Europe--the young scientist enrolled himself in the National Guard,
and, seeing one day in the Place du Panthéon a structure inscribed with
the words _autel de la patrie_, he placed upon it all the humble
means--one hundred and fifty francs--then at his disposal.
It was in that same year that Pasteur put on record his discovery of the
nature of racemic acid, his first great service to science, from which
all his other services were to proceed. As a boy he had attended the
_collège_ at Arbois where his teacher had inspired him with an ambition
to enter the great Ecole Normale. Before reaching that goal he took his
bachelor's degree in science as well as in arts at the Besançon college.
At Paris he came in contact with the leaders of the scientific
world--Claude Bernard, Balard, Dumas, Biot.
J. B. Biot had entered the ranks of science by way of the Ecole
Polytechnique and the artillery service. In 1819 he had announced that
the plane of polarized light--for example, a ray passed through Iceland
spar--is deflected to right or left by various chemical substances.
Among these is common tartaric acid--the acid of grape-juice, obtained
from wine lees. Racemic acid, however, which is identical with tartaric
acid in its chemical constituents, is optically inactive, rotating the
plane of polarized light neither to the right nor the left. This
substance Pasteur subjected to special investigation. He scrutinized the
crystals of sodium ammonium racemate obtained from aqueous solution.
These he observed to be of two kinds differing in form as a right glove
from a left, or as an object from its mirror-image. Separating the
crystals according to the difference of form, he made a solution from
each group. One solution, tested in the polarized-light apparatus,
turned the plane to the right; the other solution turned it to the left.
He had made a capital discovery of far-reaching importance, namely, that
racemic acid is composite, consisting of dextro-tartaric and
lævo-tartaric acids. Biot hesitated to credit a mere tyro with such an
achievement. The experiment was repeated in his presence. Convinced by
ocular demonstration, he was almost overcome with emotion. "My dear
boy," he exclaimed, "I have loved the sciences so much my life through
that that makes my heart jump."
Pasteur began his regular professional experience as a teacher of
physics in the Dijon lycée, but he was soon transferred to the
University of Strasburg (1849). There he married the daughter of the
rector of the académie, and three years later became Professor of
Chemistry. In 1854 he was appointed Dean of the Faculty of Sciences at
Lille, a town then officially described as the richest center of
industrial activity in the north of France. In his opening address he
showed the value and attractiveness of practical studies. He believed as
an educator in the close alliance of laboratory and factory. Application
should always be the aim, but resting on the severe and solid basis of
scientific principles; for it is theory alone which can bring forth and
develop the spirit of invention.
His own study of racemic acid, begun in the laboratories of Paris, and
followed up in the factories of Leipzig, Prag, and Vienna, had led to
his theory of molecular dissymmetry, the starting point of modern
stereo-chemistry. It now gave rise on Pasteur's part to new studies and
to new applications to the industries. He tried an experiment which
seems almost whimsical, placing ammonium racemate in the ordinary
conditions of fermentation, and observed that only one part--the
dextro-rotatory--ferments or putrefies. Why? "Because the ferments of
that fermentation feed more easily on the right hand than on the left
hand molecules." He succeeded in keeping alive one of the commonest
moulds on the surface of ashes and racemic acid, and saw the
lævo-tartaric acid appear. It was thus that he passed from the study of
crystals to the study of ferments.
In the middle of the nineteenth century little was known of the nature
of fermentation, though some sought to explain by this ill-understood
process the origin of various diseases and of putrefaction. Why does
fruit-juice produce alcohol, wine turn to vinegar, milk become sour, and
butter rancid? Pasteur's interest in these problems of fermentation was
stimulated by one of the industries of Lille. He was accustomed to visit
with his students the factories of that place as well as those of
neighboring French and Belgian cities. The father of one of his students
was engaged in the manufacture of alcohol from beetroot sugar,
and Pasteur came to be consulted when difficulties arose in the
manufacturing process. He discovered a relationship between the
development of the yeast and the success or failure of the fermentation,
the yeast globules as seen under the microscope showing an alteration of
form when the fermentation was not proceeding satisfactorily. In 1857
Pasteur on the basis of this study was able to demonstrate that
alcoholic fermentation, that is, the conversion of sugar into alcohol,
carbonic acid, and other compounds, depends on the action of yeast, the
cells of which are widely disseminated in the atmosphere.
In this year of his second great triumph Pasteur was appointed director
of science studies in the Ecole Normale, from which he had graduated in
1847. Two years later the loss of his daughter by a communicable
disease--typhoid fever--had a great effect on his sensitive and profound
mind. Many of his opponents, it is true, found Pasteur implacable in
controversy. Undoubtedly he had the courage of his convictions, and his
belief that, for the sake of human welfare, right views--_his_ views won
by tireless experiment--must prevail, gained him the name of a fighter.
But in all the intimate relations of life his essential tenderness was
manifest. Like Darwin he had a horror of inflicting pain, and always
insisted, when operations on animals were necessary in the laboratory,
on the use of anæsthetics (our command of which had been greatly
advanced by Simpson in 1847). Emile Roux said that Pasteur's agitation
at witnessing the slightest exhibition of pain would have been ludicrous
if, in so great a man, it had not been touching.
A few months after his daughter's death Pasteur wrote to one of his
friends: "I am pursuing as best I can these studies on fermentation,
which are of great interest, connected as they are with the impenetrable
mystery of life and death. I am hoping to make a decisive advance very
soon, by solving without the least lack of clearness the famous question
of spontaneous generation." Two years previously a scientist had claimed
that animals and plants could be generated in a medium of artificial air
or oxygen, from which all atmospheric air and all germs of organized
bodies had been precluded. Pasteur now filtered atmospheric air through
a plug of cotton or asbestos (a procedure which had been followed by
others in 1854), and proved that in air thus treated no fermentation
takes place. Nothing in the atmosphere causes life except the
micro-organisms it contains. He even demonstrated that a putrescible
fluid like blood will remain unchanged in an open vessel so constructed
as to exclude atmospheric dust.
Pasteur's critics maintained that if putrefaction and fermentation be
caused solely by microscopic organisms, then these must be found
everywhere and in such quantities as to encumber the air. He replied
that they were less numerous in some parts of the atmosphere than in
others. To prove his contention he set out for Arbois with a large
number of glass bulbs each half filled with a putrescible liquid. The
necks of the bulbs had been drawn out and hermetically sealed after the
contents had been boiled. In case the necks were broken (to be again
sealed immediately), the air would rush in, and (if it held the
requisite micro-organisms) furnish the conditions for putrefaction. It
was found that in every trial the contents of a certain number of the
bulbs always escaped alteration. Twenty were opened in the country near
Arbois free from human habitations. Eight out of the twenty showed signs
of putrefaction. Twenty were exposed to the air on the heights of the
Jura at an altitude of eight hundred and fifty meters above sea-level;
the contents of five of these subsequently putrefied. Twenty others were
opened near Mont Blanc at an altitude of two thousand meters and while a
wind was blowing from the Mer de Glace; in this case the contents of
only one of the bulbs became putrefied.
While his opponents still professed to believe in the creation of
organized beings lacking parents, Pasteur was under the influence of the
theory of "the slow and progressive transformation of one species into
another," and was becoming aware of phases of the struggle for existence
hitherto shrouded in mystery. He wished he said to push these studies
far enough to prepare the way for a serious investigation of the origin
of disease.
He returned to the study of lactic fermentation, showed that butyric
fermentation may be caused by organisms which live in the absence of
oxygen, while vinegar is produced from wine through the agency of
bacteria freely supplied with the oxygen of the air. Pasteur was seeing
ever more clearly the part played by the infinitesimally small in the
economy of nature. Without these microscopic beings life would become
impossible, because death would be incomplete. On the basis of Pasteur's
study of fermentation, his demonstration that decomposition is owing to
living organisms and that minute forms of life spring from parents like
themselves, his disciple Joseph Lister began in 1864 to develop
antiseptic surgery.
Pasteur's attention was next directed to the wine industry, which then
had an annual value to France of 500,000,000 francs. Might not the
acidity, bitterness, defective flavor, which were threatening the
foreign sale of French wines, be owing to ferments? He discovered that
this was, indeed, the case, and that the diseases of wine could be cured
by the simple expedient of heating the liquor for a few moments to a
temperature of 50° to 60° C. Tests on a considerable scale were made by
order of the naval authorities. The ship Jean Bart before starting on a
voyage took on board five hundred liters of wine, half of which had been
heated under Pasteur's directions. At the end of ten months the
_pasteurized_ wine was mellow and of good color, while the wine which
had not been heated had an astringent, almost bitter, taste. A more
extensive test--seven hundred hectoliters, of which six hundred and
fifty had been pasteurized--was carried out on the frigate la Sibylle
with satisfactory results. Previously wines had been preserved by the
addition of alcohol, which made them both dearer and more detrimental to
health.
In 1865 Pasteur was called upon to exercise his scientific acumen on
behalf of the silk industry. A disease--_pébrine_--had appeared among
silkworms in 1845. In 1849 the effect on the French industry was
disastrous. In the single _arrondissement_ of Alais an annual income of
120,000,000 francs was lost for the subsequent fifteen years. The
mulberry plantations of the Cévennes were abandoned and the whole region
was desolate. Pasteur, at the instigation of the Minister of
Agriculture, undertook an investigation. After four or five years, in
spite of repeated domestic afflictions and the breakdown of his own
health, he arrived at a successful conclusion. _Pébrine_, due to
"corpuscles" readily detected under the microscope, could be recognized
at the moment of the moth's formation. A second disease, _flacherie_,
was due to a micro-organism found in the digestive cavity of the moth.
Measures were taken to select the seed of the healthy moths and to
destroy the others. These investigations revealed the infinitesimally
small as disorganizers of living tissue, and brought Pasteur nearer his
purpose "of arriving," as he had expressed it to Napoleon III in 1863,
"at the knowledge of the causes of putrid and contagious diseases."
Returning in July, 1870, from a visit to Liebig at Munich, Pasteur heard
at Strasburg of the imminence of war. All his dreams of conquest over
disease and death seemed to vanish. He hurried to Paris. His son,
eighteen years of age, set out with the army. Every student of the
Ecole Normale enlisted. Pasteur's laboratory was used to house soldiers.
He himself wished to be enrolled in the National Guard, and had to be
told that a half-paralyzed man could not render military service. He was
obsessed with horror of wanton bloodshed and with indignation at the
insolence of armed injustice. Trained to serve his country only in one
way he tried, but in vain, to resume his researches. He retired to the
old home town of Arbois, and sought to distract his mind from the
contemplation of human baseness. Arbois was entered by the enemy in
January with the usual atrocities of war. Pasteur accompanied by wife
and daughter had gone in search of his son, sick at Pontarlier. The boy
was restored to health and returned to his regiment the following month.
During this crisis Pasteur and his friends felt, as many English
scientists feel in 1917, in reference to ignorance in high places. "We
are paying the penalty," he said, "of fifty years' forgetfulness of
science, and of its conditions of development." Again he speaks, as
Englishmen to-day very well might, of the neglect, disdain even, of the
country for great intellectual men, especially in the realm of exact
science. In the same strain his friend Bertin said that after the war
everything would have to be rebuilt from the top to the bottom, the top
especially. Pasteur recalled the period of 1792 when Lavoisier,
Berthollet, Monge, Fourcroy, Guyton de Morveau, Chaptal, Clouet, and
other scientists had furnished France with gunpowder, steel, cannon,
fortifications, balloons, leather, and other means to repel unjust
invasion.
On the day after Sedan the Quaker surgeon Lister had published
directions for the use of aqueous solutions of carbolic acid to destroy
septic particles in wounds, and of oily solutions "to prevent
putrefactive fermentation from without." He recognized that the earlier
the case comes from the field the greater the prospect of success.
Sédillot (the originator of the term "microbe"), at the head of an
ambulance corps in Alsace, was a pioneer in the rapid transport of
wounded from the field of battle. He knew the horrors of purulent
infection in military hospitals, and regretted that the principles of
Pasteur and Lister were not more fully applied.
After the war was over, Pasteur kept repeating his life-long
exhortation: We must work--"_Travaillez, travaillez toujours!_" He
applied himself to a study of the brewing industry. He did not believe
in spontaneous alterations, but found that every marked change in the
quality of beer coincides with the development of micro-organisms. He
was able to tell the English brewers the defects in their output by a
microscopic examination of their yeast. ("We must make some friends for
our beloved France," he said.) Bottled beer could be pasteurized by
bringing it to a temperature of 50° to 55° C. Whenever beer contains no
ferments it is unalterable. His scrupulous mind was coming ever closer
to the goal of his ambition. This study of the diseases of beer led him
nearer to a knowledge of infections. Many micro-organisms may, _must_,
be detrimental to the health of man and animals.
In 1874 the Government conferred upon Pasteur a life annuity of twelve
thousand francs, an equivalent of his salary as Professor of Chemistry
at the Sorbonne. (He had received appointment in 1867, but had been
compelled by ill-health to relinquish his academic functions.) The grant
was in all respects wise. Huxley remarked that Pasteur's discoveries
alone would suffice to cover the war indemnity of five milliards paid by
France to Germany in 1871. Moreover, all his activities were dictated by
patriotic motives. He felt that science is of no country and that its
conquests belong to mankind, but that the scientist must be a patriot in
the service of his native land.
Pasteur now applied his energies to the study of virulent diseases,
following the principles of his earlier investigations. He opposed those
physicians who believed in the spontaneity of disease, and he wished to
wage a war of extermination against all injurious organisms. As early as
1850 Davaine and Rayer had shown that a rod-like micro-organism was
always present in the blood of animals dying of anthrax, a disease which
was destroying the flocks and herds of France. Dr. Koch, who had served
in the Franco-Prussian War, succeeded in 1876 in obtaining pure cultures
of this bacillus and in defining its relation to the disease. Pasteur
took up the study of anthrax in 1877, verified previous discoveries,
and, as we shall see, sought means for the prevention of this pest. He
discovered (with Joubert and Chamberland) the bacillus of malignant
edema. He applied the principles of bacteriology to the treatment of
puerperal fever, which in 1864 had rendered fatal 310 cases out of 1350
confinements in the Maternité in Paris. Here he had to fight against
conservatism in the medical profession, and he fought strenuously, one
of his disciples remarking that it is characteristic of lofty minds to
put passion into ideas. Swine plague, which in the United States in 1879
destroyed over a million hogs, and chicken cholera, also engaged his
attention.
Cultures of chicken cholera virus kept for some time became less active.
A hen that chanced to be inoculated with the weakened virus developed
the disease, but, after a time, recovered (much as patients after the
old-time smallpox inoculations). It was then inoculated with a fresh
culture supposed sufficient to cause death. It again recovered. The use
of the weakened inoculation had developed its resistance to infection. A
weakened virus recovered its strength when passed through a number of
sparrows, the second being inoculated with virus from the first, the
third from the second, and so on (this species being subject to the
disease). Hens that had not had chicken cholera could be rendered immune
by a series of attenuated inoculations gradually increasing in strength.
In the case of anthrax the virus could be weakened by keeping it at a
certain temperature, while it could be strengthened by passage through a
succession of guinea-pigs. There are of course many instances where
pathogenic bacteria lose virulence in passing from one animal to
another, the human smallpox virus, for example, producing typical cowpox
in an inoculated heifer. These facts help to explain why certain
infections have grown less virulent in the course of history, and why
infections of which civilized man has become tolerant prove fatal when
imparted to the primitive peoples of Australia.
Pasteur's preventive inoculation for anthrax was tested under dramatic
circumstances at Melun in June, 1881. Sixty sheep and a number of cows
were subjected to experiment. None of the sheep that had been given the
preventive treatment died from the crucial inoculation; while all those
succumbed which had not received previous treatment. The test for the
cows was likewise successful. Pasteur thought that in places where sheep
dead of anthrax had been buried, the microbes were brought to the
surface in the castings of earthworms. Hence he issued certain
directions to prevent the transmission of the disease. He also aided
agriculture by discovering a vaccine for swine plague.
When Pasteur at the age of fifteen was in Paris, overcome with
homesickness, he had exclaimed, "If I could only get a whiff of the old
tannery yard, I feel I should be cured." Certainly every time he came in
contact with the industries--silk, wine, beer, wool--his scientific
insight, Antæus-like, seemed to revive. All his life he had preached the
doctrine of interchange of service between theory and practice, science
and the occupations. What he did is more eloquent than words. His theory
of molecular dissymmetry, that the atoms in a molecule may be arranged
in left-hand and right-hand spirals or other tridimensional figures
corresponding to asymmetrical crystals, touches the abstruse question of
the constitution of matter. His preventive treatment breathes new life
into the old dictum _similia similibus curantur_. The view he adopted of
the gradual transformation of species offers a new interpretation of the
speculations of philosophy in reference to being and becoming and the
relation of the real to the concrete. Yet Pasteur felt he could learn
much of value from the simplest shepherd or vine-dresser.
He was complete in the simplicity of his affections, in his compassion
for all suffering, in the warmth of his religious faith, and in his
devotion to his country. He thought France was to regain her place in
the world's esteem through scientific progress. He was therefore
especially gratified in August, 1881, at the thunders of applause which
greeted his appearance at the International Medical Congress in London.
There he was introduced to the Prince of Wales (_fondateur de l'Entente
Cordiale_), "to whom I bowed, saying that I was happy to salute a friend
of France."
Pasteur's investigation of rabies began in this same year. Difficulty
was found in isolating the microbe of the rabic virus, but an
inoculation from the medulla oblongata of a mad dog injected into one of
the brain membranes (dura mater) of another dog invariably brought on
the symptoms of rabies. To obtain attenuation of the virus it was
sufficient to dry the medulla taken from an infected rabbit. The
weakened virus increased in strength when cultivated in a series of
rabbits. Pasteur obtained in inoculations of graded virulence, which
could be administered hypodermically, a means of prophylaxis after
bites. He conjectured that in vaccinal immunity the virus is accompanied
by a substance which makes the nervous tissue unfavorable for the
development of the microbe.
It was not till 1885 that he ventured to use his discovery to prevent
hydrophobia. On July 6 a little boy, Joseph Meister, from a small place
in Alsace was brought by his mother to Paris for treatment. He had been
severely bitten by a mad dog. Pasteur, with great trepidation, but moved
by his usual compassion, undertook the case. The inoculations of the
attenuated virus began at once. The boy suffered little inconvenience,
playing about the laboratory during the ten days the treatment lasted.
Pasteur was racked with fears alternating with hopes, his anxiety
growing more intense as the virulence of the inoculations increased. On
August 20, however, even he was convinced that the treatment was a
complete success. In October a shepherd lad, who, though badly bitten
himself, had saved some other children from the attack of a rabid dog,
was the second one to benefit by the great discovery. Pasteur's exchange
of letters with these boys after they had returned to their homes
reveals the kindliness of his disposition. His sentiment toward children
had regard both to what they were and to what they might become. One
patient, brought to him thirty-seven days after being bitten, he failed
to save. By March 1 Pasteur reported that three hundred and fifty cases
had been treated with only one death.
When subscriptions were opened for the erection and endowment of the
Pasteur Institute, a sum of 2,586,680 francs was received in
contributions from many different parts of the world. Noteworthy among
the contributors were the Emperor of Brazil, the Czar of Russia, the
Sultan of Turkey, and the peasants of Alsace. On November 14, 1888,
President Carnot opened the institution, which was soon to witness the
triumphs of Roux, Yersin, Metchnikoff, and other disciples of Pasteur.
In the address prepared for this occasion the veteran scientist wrote:--
"If I might be allowed, M. le Président, to conclude by a philosophical
remark, inspired by your presence in this home of work, I should say
that two contrary laws seem to be wrestling with each other at the
present time; the one a law of blood and death, ever devising new means
of destruction and forcing nations to be constantly ready for the
battlefield--the other, a law of peace, work, and health, ever
developing new means of delivering man from the scourges which beset
him.
"The one seeks violent conquests, the other the relief of humanity. The
latter places one human life above any victory; while the former would
sacrifice hundreds and thousands of lives to the ambition of one. The
law of which we are the instruments seeks, even in the midst of carnage,
to cure the sanguinary ills of the law of war; the treatment inspired by
our antiseptic methods may preserve thousands of soldiers. Which of
these two laws will ultimately prevail God alone knows. But we may
assert that French science will have tried, by obeying the law of
humanity, to extend the frontiers of life."
REFERENCES
W. W. Ford, _The Life and Work of Robert Koch_, Bulletin of the Johns
Hopkins Hospital, Dec. 1911, vol. 22.
C. A. Herter, _The Influence of Pasteur on Medical Science_, Bulletin
of the Johns Hopkins Hospital, Dec. 1903, vol. 14.
E. O. Jordan, _General Bacteriology_ (fourth edition, 1915).
Charles C. W. Judd, _The Life and Work of Lister_, Bulletin of the
Johns Hopkins Hospital, Oct. 1910, vol. 21.
Stephen Paget, _Pasteur and After Pasteur_.
W. T. Sedgwick, _Principles of Sanitary Science_.
René Vallery-Radot, _Life of Pasteur_.