JOHN SWAMMERDAM.
As a naturalist, Swammerdam is chiefly celebrated for the extent and accuracy of his inquiries into the structure of insects; though anatomy and physiology are equally indebted to his labours. He was the first who discovered the method of rendering the blood-vessels more easy to be traced in dissection, by injecting them with coloured wax in a fluid state; and although he cannot for that reason alone claim all the discoveries that have been made in anatomy, any more than the first person who skinned birds can claim the honour of determining the numerous species that have been conveyed from distant countries, or he who first cut a slice of petrified wood, all the results that have emanated from his experiment, yet he certainly devised the means of extending our knowledge of the human body as well as of pathology. His works on insects are the following:—1. The General History of Insects, published in Dutch at Utrecht in 1669, and subsequently in French and Latin, in which he gives a classification of these animals, founded on their structure and metamorphoses. 2. The History of the Ephemeris, published in Dutch at Amsterdam in 1675, and in Latin at London in 1681. 3. The Biblia Naturæ, sive Historia Insectorum in Classes Certas Redacta, Leyden, 1737-38, 2 vols folio, which has been translated into German, English, and French. This important work was published after his death by Boerhaave, in Dutch and Latin, and contains a masterly exposition of the structure of such insects as came under his observation.
It has been remarked by an eminent entomologist, that natural history, which, during the long series of ages in which barbarism reigned, shared the fate of the other sciences, underwent the same treatment when a taste for knowledge began to revive. For example, it was chiefly in Aristotle that the history of animals was sought; whereas, if Aldrovandi, Gesner, Moufet, and other physiologists, had studied nature as much as they studied the ancient writers, the assiduous labour of so many active minds would have secured for that science a more sure and rapid progress. The material world was then observed only for the purpose of confirming the reports made by the authors of antiquity. At length Nature opened the eyes of those who were trying to see in her only what they had seen in Aristotle and Pliny. She disclosed to them facts worthy of being noticed, which they vainly sought in the books which they imagined to contain every thing; and unfolded others, which gave them reason to doubt the truth of those that had been transmitted from former ages. After having thrown off the fetters of authority, farther, perhaps, than was quite consistent with the respect that was really due to the ancients, men perceived that they ought to study facts, verify whatever had been related, and try to discover more. It was thus that Malpighi, Swammerdam, Redi, and other illustrious authors proceeded. Even those, such as Goedart and Madame Merian, who, from an ignorance in some degree fortunate, were unable to read the ancients, laboured with advantage as observers.[H]
The subject of this memoir was born at Amsterdam on the 12th February 1637. His father, an apothecary, was fond of natural history, and, being in prosperous circumstances, embellished his house with preserved animals, shells, and minerals, insomuch that it became an object of attraction to the curious. Young Swammerdam was intended for the church, and received instructions in the Greek and Latin languages, to qualify him for the study of divinity; but, on seriously considering the importance of the task designed for him, he judged himself incapable of discharging the duties of a religious instructor. On representing the matter to his parents, he received their permission to commence the study of medicine. Being frequently employed in cleaning and arranging his father's cabinet, he gradually acquired a liking to natural history, and even at an early age began to form a collection of insects, which he disposed into classes, agreeably to ideas derived from observation and the descriptions of authors. Day and night he pursued his favourite employment, searching the woods and fields, the sandhills and muddy shores, the lakes, rivers, and canals, for insects, worms, and mollusca, until he acquired, even while a youth, a more extensive and more accurate knowledge of the lower animals than all the naturalists who had preceded him.
In 1661, he went to Leyden, for the purpose of attending the lectures at the celebrated university of that city. There he remained two years, studying surgery with Van Horne, and medicine with Franciscus Sylvius de le Boe, with as much diligence as he had previously displayed in his other pursuits. During the whole of this time he enjoyed the friendship of Steno and De Graaf; and, becoming much attached to the study of anatomy, he exerted his utmost ingenuity in devising means for effectually preserving his preparations.
He then went to Paris to improve himself in his profession. There he continued the examination of insects, and had the good fortune to discover the valves in the lymphatic vessels. After this he resided for some time at Lyons, where he lived on terms of intimacy with Thevenot the celebrated traveller, who introduced him to the learned men by whom his house was frequented. In their society he usually remained a listener, and could not be prevailed upon to communicate his ideas; but, being repeatedly urged to exhibit one of his minute dissections, he gratified the wishes of his friends, and, by the profound knowledge which he displayed, acquired at once their esteem and admiration. Thevenot recommended him to Van Beuningen, a senator at Amsterdam, who, on his returning to that city, obtained permission for him to examine the bodies of patients dying in the hospital,—an opportunity of increasing his knowledge which he took care not to neglect.
In his native town he frequented a society of medical men, who met once a-fortnight for the purpose of discussing subjects connected with their profession, and made observations on the structure of the spinal marrow and nerves, on respiration, and on the effects produced by the injection of fluids into the blood-vessels of animals.
About the end of 1666, he returned to Leyden with the view of obtaining his medical diploma, and there continued his researches in company with his former teacher, Van Horne, in whose house he injected the uterine vessels with wax,—a method of showing the distribution of the arteries and veins afterwards greatly improved by him, and which has been productive of much advantage in the study of anatomy. In February 1667, he received the degree of doctor, and in March published his thesis on respiration, which he dedicated to Thevenot. He next invented a new method of preserving anatomical subjects by inflating them with air. But the eagerness with which he engaged in these occupations was prejudicial to his health, and he was seized with a quartan ague, which reduced him to a state of extreme debility. On recovering from this disease, he remitted his professional studies for two years; resuming the investigation of insects, the structure of which he unfolded with astonishing precision and success.
It happened about this time that the Grand Duke of Tuscany visited Amsterdam. Accompanied by Thevenot, he examined the collections made by Swammerdam and his father, and was so struck by the wonderful dissections of insects that he offered 12,000 florins for the museum, on condition that its proprietor should accompany it to Florence, and take up his residence in the palace. But the young naturalist had been no much accustomed to roam about at will, that he could not relinquish his liberty, and therefore refused the offer.
In 1669, he published his General History of Insects, which he dedicated to the senate of Amsterdam. The expense which he incurred in procuring specimens from all quarters, while no emoluments resulted from his labours, so displeased his father, that he earnestly urged him to relinquish his unprofitable pursuits, and engage in the practice of medicine. At length, finding him unwilling to follow his advice, he was obliged to threaten a total intermission of supplies; though by this time the ardent student had fallen into such a state of debility that he was totally unfit to undergo the fatigues of practice. He was, however, sensible of the propriety of the counsel which was administered to him, and retired to the country to recruit his strength; but he had scarcely arrived when he recommenced his studies, being wholly unable to resist the temptation offered by solitude and by the presence of the objects which invited his research. In the mean time, Thevenot, being made acquainted with these circumstances, urged him to return to France, generously offering him every thing necessary to enable him to follow the bent of his genius. His father, however, did not approve of this scheme, which was therefore relinquished; but the son did not the less continue to pursue his former occupations.
In 1672, he published his Miraculum Naturæ, seu Uteri Muliebris Fabrica. He soon afterwards entered upon an extensive examination of fishes, having reference chiefly to the pancreas. About this time he began to be impressed with religious ideas; becoming sensible of the vanity of human pursuits, as well as of the sinfulness of that inordinate ambition which impels men to aim at the highest place in the estimation of their fellows. He accordingly resolved to eradicate that base passion from his breast. In this state of mind he imbibed the mystical notions of the celebrated Antoinette Bourignon.
This lady, who was a native of Lisle in Flanders, had become at an early age impressed with the idea that pure Christianity was in a state of decay, and that she was called to revive it. She became governess of the hospital of her native city, and took the order and habit of St Augustin; but owing to the disturbances caused by her violent temper and pretensions to inspiration, the magistrates were obliged to expel her from her office, when she retired to Ghent. The fortune which she inherited from her parents, and that bequeathed to her by her convert De Cordt, enabled her to publish several works of her own composition, and rendered her, notwithstanding the deformity of her person, the object of much hypocritical admiration. Such was her extreme parsimony, and so inconsistent was her conduct with her professions, that she declared she would rather throw her wealth into the sea than bestow the smallest sum on the poor, or on "beastly persons who had no souls to be saved."
She was at that time in Holstein; and Swammerdam wrote to a friend of his who accompanied her, to obtain permission to consult her in writing respecting his doubts. The result of their correspondence was a resolution on his part no longer to addict himself exclusively to pursuits which had reference to this world only, but to endeavour to make his peace with God. He did not, however, entirely relinquish his anatomical studies, but on the contrary engaged with astonishing ardour in the examination of the structure of bees, which he finished on the last day of September 1674. "He had laboured so assiduously at this work," says Boerhaave, "as to destroy his constitution; nor did he ever recover even a shadow of his former strength. The labour, in fact, was beyond the power of ordinary men: all day he was occupied in examining subjects, and at night described and delineated what he had seen by day. At six in the morning, in summer, he began to receive sufficient light from the sun to enable him to trace the objects of his examination. He continued dissecting till twelve, with his hat removed lest it should impede the light, and in the full blaze of the sun, the heat of which caused his head to be constantly covered with a profuse perspiration. His eyes being continually employed in this strong light, the effect of which was increased by the use of the microscope, they were so affected by it, that after mid-day he could no longer trace the minute bodies which he examined, although he had then as bright a light as in the forenoon." A month of this excessive labour was necessary to examine and depict the intestines of bees alone; and the investigation of their entire structure cost him much additional labour; and all this was done, with a body debilitated by disease, and a mind agitated by conflicting passions, amid sighs and tears. At one time the bent of his disposition impelled him to investigate the wonderful works of Omnipotence; at another a voice within told him that he ought to set his affections on God alone. After finishing his examination of the structure of bees, he was so affected with remorse, that he gave the manuscript and drawings to a friend, careless what might happen to them. At the same time, however, he wrote two letters to Boccone, on the nature of corals.
These occupations being ended, he was more powerfully impressed than ever with the vanity of human pursuits, and after this period he never engaged in his customary investigations. He acknowledged that hitherto ambition alone had incited him to undergo so many labours, but now resolved to devote the remainder of his life to the cultivation of Christian piety. Being encouraged in this resolution by the approbation of Antoinette Bourignon, he firmly adhered to it; and estimating the annual sum necessary for his subsistence at 400 Dutch florins, he endeavoured to dispose of his collections, which formed the only treasures that he possessed. For this purpose, he applied to Thevenot, who, however, was unable to find a purchaser in France. He then had recourse to another friend, Nicolas Steno, who had abjured the Protestant faith and was living at Florence, and whom he requested to represent the matter to the Grand Duke of Tuscany, in case he might feel disposed to purchase them. This person advised him to follow his example, relinquish his creed, embrace the Catholic faith, and proceed to Florence, promising that he should induce the duke to accept the offer. Swammerdam replied indignantly, that he would not sell his soul for money.
Being without any fixed occupation, he devoted his leisure to arranging and cleaning the contents of his museum, and writing out a catalogue of them. They consisted of anatomical preparations and insects, of the latter of which there were nearly three thousand distinct species. These were all described and arranged into classes, and the entire structure of many of them had been demonstrated by the most minute dissection. He then published his Treatise on the Ephemeris, which he had commenced when in France, and which is considered as one of the most remarkable productions of any age. He did not, however, venture upon this step without consulting Bourignon. These arrangements completed, he now determined in earnest to lead a holy life, and being desirous of a personal consultation with his directress, he went to Holstein, where he remained with her some time. On returning to Amsterdam, he again endeavoured to dispose of his museum, but without success; and his sister, who had hitherto presided over the domestic establishment, happening at this time to be married, his father resolved upon living with his son-in-law, so that he was obliged to look out for another residence. On this occasion his allowance was limited to 200 florins, and as he could not find any one to purchase his collection he was reduced to great perplexity. However, a thought struck him that he might apply to an old friend, who had formerly treated him with great kindness; but in this he also failed.
In the following year, his father died, leaving him heir to his property, which was sufficient for his support; but he became involved in disputes with his sister, which, together with his assiduous endeavours to discharge his religious duties, so agitated his mind, that he was again seized with a severe ague. For three entire months he was confined to his bed, and even when the accessions of the fever had become more gentle and less frequent, he still persisted in remaining in the house. In vain did his friends, Sladus, Ruysch, Schrader, Hotton, and Guenellon, urge upon him the propriety of adopting means for improving his health. He would not yield to their proposals; and, when they still persisted, at length maintained an obstinate silence.
Finding all his endeavours to sell his collection fruitless, he determined to expose it to public auction; but before the period arrived, his disease was much aggravated by the various agitations to which his mind was now habitually subject. The fever proved again regular and continuous, the countenance was emaciated, the eyes were sunk, the feet, the legs, and at length the whole body, dropsical. His friends dared not speak to him respecting his former studies, for he detested all allusion to them, and wished to withdraw his mind entirely from earthly concerns. At length, on the 25th January 1670, when he perceived his end approaching, he wrote his will, leaving to Thevenot all his original manuscripts on the history of bees, butterflies, and anatomy, with 52 plates; all of which were at that time in the house of Herman Wigendorp in Leyden, to whom they had been delivered to be translated into Latin. He bequeathed his property to Margaret Volckers, wife of Daniel de Hoest, appointing her and Christopher Wyland his executors. The remainder of his time he spent in devotion, and died on the 17th February.
It was some years before Thevenot obtained possession of the manuscripts, and after his death they passed into various hands, but were bought in 1727 by the illustrious Boerhaave, who arranged and published them in two folio volumes, prefixing a life of the author, from which we have drawn the materials of this notice.
The learned editor gives an interesting account of the instruments and expedients employed by Swammerdam in dissecting insects and other minute animals. When the anatomical preparations, insects, and apparatus, were offered for sale, no purchaser could be found, and the collection was subsequently dispersed. The manuscripts and drawings of the Biblia Naturæ were deposited by Boerhaave in the library of the University of Leyden.
The works of Swammerdam contain more original and accurate observations than those of any naturalist who preceded him, excepting Aristotle. He refuted numerous errors committed by his predecessors, and carried his observations to a degree of minuteness and accuracy truly astonishing; but it is not a little surprising that he succeeded less in describing the structure of large objects than in delineating the organs of the most minute.
His classification of insects differs very materially from those now in use. The characters of his four classes he derives from the state in which each insect appears after its birth, and those through which it passes before attaining its entire development. In the first he places all those which issue from the egg with nearly the same form as that which they have at the period of their full growth; such as spiders, slugs, leeches, &c. In the second are included those which, like the grashopper, issue with six feet, and some time after cast off the covering under which the wings were concealed. These insects run or leap with agility in their first stage, which is not the case with those of the next class. To the third are referred insects which undergo greater changes, such as caterpillars, and which proceed from the egg in the state of a worm, remain in that state for some time, cast off their hairy covering, assume the form of a chrysalis, when they become motionless, and finally emerge in a winged state. The fourth class consists of such as, like the common fly, on changing the form under which they issued from the egg to assume that of a worm, do not cast their covering, but become separated from it, while it remains and forms a shell or egg-like investiture, in which the insect remains in the pupa state until it finally emerges with wings.
The history of Swammerdam must excite our sympathy and commiseration; but that, as some have alleged, he lost his reason towards the end of his life, and became subject to mania, arising from religious melancholy, no one who has any share of that piety which he evinced will feel disposed to admit. Although he lived in misery, the close of his life was perhaps more enviable than that of many who have gone smiling to their final rest; and it is well for those who, before the period arrives when as the tree falls so it must lie, can like him become truly sensible of the vanity of all earthly pursuits, even although after death they should be pointed out as the victims of a distempered imagination.