Popular Science Monthly/Volume 24/November 1883/Sketch of Lamarck

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LAMARCK.


SKETCH OF LAMARCK.

THERE are two classes of scholars. Those of the one class, who travel in the footsteps of their predecessors, increase the domain of knowledge, and add new discoveries to those that were made before them; their labors are immediately appreciated, and they enjoy their well-earned fame in full measure. Others, who leave the trodden ways, emancipate themselves from traditions, and expose to the light of the sun the germs of future discovery which lie buried in the teachings of the present. Sometimes they are appreciated at their full value during their lifetime, but more frequently they pass away, misunderstood by the scientific public of their time, which is incapable of comprehending and following them. Indolence, routine, and ignorance oppose an invincible resistance against them during their career, and they die isolated and forsaken. In the mean time, science advances, facts increase, methods are perfected, and their contemporaries who survive them gradually come up to the mark they had left. Then all their forgotten services are brought into the light, justice is partly done to their labors, their genius is admired, it is recognized that they foresaw the future, and a tardy posthumous fame comforts their pupils for the neglect which the masters had to endure during the years of vain struggle for the triumph of the truth.

Lamarck belonged to both of these classes. By his descriptive labors in botany and zoölogy, and by the improvements which he introduced in the classification of animals, and which were accepted by his contemporaries, he gained a first place among the naturalists of his time; but his philosophical views on organic beings in general were rejected, and did not even enjoy the honor of a sincere testing. They were only accorded a polite silence, or treated with scornful irony.

Jean Baptist Pierre Antoine de Monet, known as the Chevalier de Lamarck, was born on the 1st of August, 1744, at Bazentin, a little town between Albert and Bapaume, in Picardy. He was the eleventh child of Pierre de Monet, lord of the manor, who was descended from an old family in the county Béarn, and called only a small hereditary estate his own. His father had designed him for the church, then the common destination for the younger sons of noble families, and took him to the Jesuit college at Amiens. This, however, was not the natural vocation of our young nobleman. Everything in his family associations inclined his mind toward military fame. His eldest brother had fallen in the breach at the siege of Berg-op-Zoom; the other two brothers were still in the service, while France was exhausting its forces in an unequal contest. His father opposed his wishes on this point; but, when the father died, Lamarck, following his own inclination, betook himself on a poor horse to the army, which was encamped near Lippstadt, in Westphalia. He was furnished with a letter of introduction from Frau von Lameth, proprietor of a neighboring estate, to Colonel de Lastic, of the Beaujolais regiment. This officer, when he saw the seventeen-year-old youth, who looked much younger, sent him to his quarters. A battle took place on the next day. M. de Lastic drew up his regiment, and noticed his protégé in the front rank of a company of grenadiers. The French army was under the command of Marshal Broglie and Prince Soubise while the allied troops were commanded by Prince Ferdinand of Brunswick. The two French officers, who did not agree together, were killed. The company Lamarck had joined was broken up by the enemy's fire, and was forgotten in the confusion of the retreat. The officers and under-officers were killed, and only fourteen were left standing. The oldest of these counseled retreat; Lamarck, who had, on the spur of the moment, improvised himself to the command, answered: "We have been assigned to this position, and we must not forsake it till we are relieved." The colonel, who now remarked that the company was not with his regiment, recalled it by an order which he managed to get back to it by a secret way. On the next day Lamarck was appointed an officer, and soon afterward a lieutenant. Fortunately for science, this brilliant beginning of a military career was not decisive of the future of the youth. After the conclusion of peace he performed garrison duty in Toulon and Monaco, till an inflammation of the lymphatic glands of the neck made it necessary for him to go to Paris to undergo an operation by Tenon, the scar of which he carried all his life.

The aspect of the vegetation in the neighborhood of Toulon and Monaco had attracted the attention of the young officer, who had already acquired some knowledge of botany from the "Traité des plantes usuelles" of Chomel. After he withdrew from the military service and had been awarded a modest pension of four hundred francs, he became engaged with a banker in Paris. Moved by an irresistible impulse to the study of Nature, he observed from his attic-room the forms and movements of the clouds, and made himself acquainted with plants in the royal gardens, and by means of botanical excursions. He felt that he was on the right way, and recalled Voltaire's judgment on Condorcet, that discoveries to come would secure him more fame with posterity than a company of soldiers. Dissatisfied with the botanical systems in use, he wrote in a half-year his "Flore française," and published his "Clé dichotomique," by the aid of which it is easy for a beginner to ascertain the name of the plants he is accustomed to see. This was in 1778. Through Rousseau botany became a fashionable study; the lords and ladies of the world of society busied themselves with plants; Buffon had the three volumes of the "Flore française" published at the Royal Printing-House; and in the next year Lamarck entered the Academy of Sciences. Buffon, who wished his son to travel, gave him Lamarck as a conductor, with a commission from the government. They journeyed through Holland, Germany, and Hungary, and Lamarck became acquainted with Gleditsch in Berlin, Jaquin in Vienna, and Murray in Göttingen.

The "Encyclopédic methodique," begun by d'Alembert and Diderot, was not yet finished. Lamarck composed four volumes of this work, and in them described all the then known plants the names of which begin with the letters from A to P—a huge work, which was completed by Poiret, and included twelve volumes, appearing between 1783 and 1817. A still more important work, which also forms a part of the "Encyclopædia," and is continually quoted by botanists, is entitled "Illustration des genres" ("Illustration of Genera"), in which Lamarck described the characteristics of two thousand species. The work, says the title-page, is illustrated with nine hundred copper-plate engravings. Only a botanist can form a conception of the researches in herbaria, gardens, and books, which such an undertaking demanded. Lamarck accomplished it all by means of the most restless industry. If a traveler came to Paris, he was the first one to announce himself to him. Sonnerat returned from India with immense collections. Nobody but Lamarck took the trouble to look at them, and Sonnerat was so pleased with him for this that he presented the splendid herbarium to him. In spite of his indefatigable labors, Lamarck's situation was miserable enough. He lived by his pen, and in the service of the book-sellers. Even the petty position of overseer of the Royal Herbarium was refused him. Like the majority of naturalists, he contended for many years with the difficulties of life. A fortunate circumstance, which gave his activity another direction, brought improvement in his condition. The convent ruled over France. Carnot organized victory. Lamarck undertook to organize the sciences. The Museum of Natural History was founded upon his motion. They had been able to name professors for all the branches except zoölogy; but, in those times of ardent enthusiasm, France found warriors and men of science wherever it needed them. Étienne Geoffroy Saint-Hilaire was twenty-one years old, and was engaged with Haity in mineralogy. Daubenton said to him: "I take the responsibility for your inexperience upon myself; I have the authority of a father over you. Be so bold as to assume the chair of zoölogy, and it may be said some day that you have made a French science of it." Geoffroy acceded, and undertook the higher animals. Lakanal had well comprehended that a single professor would not be adequate to the task of working out the whole animal kingdom. Since the classification of the vertebrates only was taken care of by Saint-Hilaire, the whole list of invertebrates, including the insects, mollusks, worms, zoophytes, etc., still remained in chaos—in the unknown. Lamarck, says Michelet, undertook the unknown. He had busied himself a little, under Bruguières's direction, with the mollusks, but he still had nearly all to learn, or, to speak more accurately, nearly all to create, in that uninvestigated world in which Linnæus had failed to introduce the methodical arrangement which he had been so successful in introducing among the higher animals. After devoting a year to preliminary studies, Lamarck began his lectures in the Museum in the spring of 1794; he immediately instituted the great division of animals into vertebrates and invertebrates, which has become fixed in science. Adhering to the Linnæan division of the vertebrates into mammalia, birds, reptiles, and fishes, he divided the invertebrates into mollusks, insects, worms, echinoderms, and polyps. In 1799 he separated the order of crustaceans from the insects with which it had been confounded; in 1800 he separated the arachnids from the insects; in 1802 he set off the annelids as a subdivision of the worms, and the radiates as separable from the polyps. Time has confirmed the justice of his division, which depends in every respect upon the organization of the animals. This is the rational method, incorporated in science by Cuvier, Lamarck, and Geoffroy Saint-Hilaire.

As our sketch has so far dealt only with Lamarck's achievements in natural history, we pass with a simple mention a few works in which he treated of physics and chemistry; mistakes of a good intention, which attempted to establish truths that rest exclusively on experiment, by reasoning alone, or to resuscitate old theories like that of phlogiston. These efforts did not even receive the honor of a contradiction; they did not deserve it; and they should serve as a warning to all those who would write upon any science without being acquainted with it, and without having had practical experience in it.

The generalizations of Lamarck in geology and meteorology, sciences which at the time he wrote had hardly come into existence, were mistaken in another sense. They were premature. Every science must begin with the knowledge of facts and phenomena. When these are numerous enough, a partial generalization is possible; as they increase, the basis grows broader; but systems which can justly claim to be absolute and definitive can never be, for they presuppose that all the phenomena and facts are known, a condition which will be impossible as long as man lives. In the beginning of this century geology did not exist, and little was known of the matters of which it treats; but systems were created that included the whole earth. Lamarck elaborated his system in 1802; and twenty-three years afterward the clear mind of Cuvier succumbed to the prevailing tendency, and he published his treatise on the revolutions of the globe. It was Lamarck's merit that he perceived that there were no revolutions in geology, and that the slow manifestations of force through hundreds of thousands of years far better explained the wonderful changes of which our planet has been the scene than violent disturbance could do. "To nature," he said, "time is nothing: it is no obstacle. Nature always has time enough at its disposal; time is a means of unlimited capacity, through which it produces the greatest as well as the smallest effects."

He was the first who distinguished the littoral fossils from the deep-sea fossils. Yet no one will to-day accept his idea that the sea, by force of its ebb and flow, could have hollowed out its bed and changed its local position on the surface of the earth without altering the relative level of the different points on the surface. In view of recognized facts, it is impossible to ascribe the origin of all the valleys to the wear of the waters. Just as Lamarck's conclusions in the science of organic beings, which he knew so well, were sharp-sighted and prophetic, so were they, in the sciences which were strange to him, careless, hazardous, and destined to be contradicted in the future. Like the metaphysicians, he built in the air, and his structure, like theirs, fell for want of a firm foundation. Limited by his lectures in the Museum, and by the duty of classifying the collections to a definite scientific work, he devoted himself entirely to this double object. In 1802 he published his "Considérations sur l'organisation des corps vivants" (Considerations on the Organization of Living Bodies); in 1809, his "Philosophic Zoologique" ("Zoölogical Philosophy"), an expansion of the "Considerations," and from 1816 to 1822 the "Histoire naturelle des animaux sans vertèbres" ("Natural History of the Invertebrate Animals"), in seven volumes. This was his principal work, and, as it was exclusively descriptive and systematic, it was received by the learned world with great favor. His paper on the fossil mollusks of the neighborhood of Paris, in which his profound knowledge of living mollusks permitted him to make an accurate classification of those remains of animals that had laid for thousands of years in the bosom of the earth, was likewise well received.

Lamarck had begun his zoölogical work when fifty years old. The painstaking study of minute animals, visible only through the lens and the microscope, wore upon his eyesight, which grew feebler and feebler till he became totally blind. Four times married, the father of seven children, he saw his little inheritance, and also his earlier savings, disappear in one of those high-sounding speculations with which a credulous public is often deluded. His modest salary as a professor only kept him from want. The friends of science, whom his fame as a zoölogist attracted to him, were shocked when they observed in what neglect he lived. He spent the last years of his life in total darkness, but comforted by the loving care of his two daughters. The elder daughter wrote at his dictation a part of the sixth, and some of the seventh, volume of his "History of the Invertebrates." After the father could not leave his room, the daughter would not go out of the house; and, when she did at last go out, she could not endure the open air from which she had been excluded so long. Lamarck died on the 18th of December, 1829, at the age of eighty-five years. It has been more the fashion to condemn Lamarck for his speculations than to give him the credit that is his due for his great work in classification. Recently, however, two naturalists have endeavored to present these speculations in a more favorable light, and, without denying that they embodied much that was not well enough established, to show that much in them was only anticipatory of what science has since accepted: Herr Haeckel, in Germany, who declares that in Darwin, Goethe, and Lamarck, "each of the three great civilized nations of middle Europe has presented mankind in the course of a hundred years with an intellectual hero of the first rank, who comprehended in its full significance the fundamental idea of the concordant development of the world from natural causes"; and M. Barthélemy, in France, who considers that Lamarck was a forerunner of Darwin, and a greater than he.

M. Barthélemy, while admitting that Lamarck's theories on physics, chemistry, and meteorology were frequently rash and lacking the precision that experiment gives, says: "He believed in natural laws, in the unity and transformation of physical and physiological forces, because he attributed a special signification to nature. To him nature was a power subordinate to God, its sublime author, who must not be confounded with it, and whose function it is to put to work forces and laws which it has not made, and can not modify. His cosmical system is summarized in the three elements: God, nature, and the universe. Transformism, with Lamarck, is not born of abstract meditations and a priori conceptions, as has sometimes been said. It is connected with the whole of the theories that precede. He rose from the careful study of the immense multitude of beings he had to examine to carry order and light into the chaos of invertebrate animals. In his first lectures he began with the most rudimentary beings, the origin of which he attributed to physico-chemical forces, and then saw the organization and the circulation of the fluids become more complicated and more perfect as the scale of being rose with new faculties resulting from the acquisition of new organs derived from the cellular tissue, and owing their origin to new wants or new circumstances in which the being found itself placed. He conceived very clearly the influence of external conditions, and attributed the modifications of organisms to two factors, one interior and constant and regular in its operation; the other exterior and irregular, and including modifications of media, temperature, nutrition, etc. He concluded from this that a continuous chain of beings is not possible, for, if such a chain existed, it would quickly be broken by the accidental or irregular circumstances to which beings are obliged to adapt themselves."

Herr Haeckel pronounces Lamarck's "Philosophic Zoologique," in respect to its uniform and complete deduction of the development theory, as well as to its many-sided empirical basis, far more important than the similar efforts of all his contemporaries, even than the similar work of Geoffroy Saint-Hilaire, and styles it "the greatest production of the great literary epoch of the beginning of our century." According to this naturalist's review of Lamarck's system, it supposes that "all the forms of animals and plants which we distinguish as species have only a relatively temporary stability, and the varieties are incipient species. Therefore the form-group or type of the species is just as much an artificial product of our analyzing reason as are the genus, order, class, and other categories of the system. Changes in the conditions of life on one side, the use and non-use of the organs on the other side, constantly exert a formative influence on the organism; through adaptation they bring about a gradual metamorphosis of forms, the principal features of which are transmitted by inheritance from generation to generation. The whole system of animals and plants is thus peculiarly their genealogical tree, and reveals to us the relations of their natural blood-kinship. The course of development on the globe has therefore been continuous and unbroken, like that of the earth itself. . . . Lamarck regarded life as only a very complicated physical phenomenon; for all the phenomena of life depend on mechanical antecedents, which are themselves dependent on the adaptedness of the organic matter. Even the phenomena of the mental life are not different in this respect from the others. For the conceptions and acts of the mind depend upon motor-organs in the central nerve-system." He did not shrink from the solution of the difficult question of the origin of life on the globe, and assumed "that the common primitive forms of all organisms were absolutely simple beings which originated by spontaneous generation, under the combined operation of different physical causes, out of the inorganic matter in water." "Undoubtedly," adds Herr Haeckel, "the greatest defect in Lamarck's work was the insufficient number of observations and experiments which he adduced in proof of his far-reaching theories." A great part of Darwin's immense success was owing to the fact that he was backed by a host of clear and convincing observations and experiments, while "poor Lamarck, trusting too much to the logical acumen of the naturalist, in great part neglected them."