Happy in this toil when he was well, for it was all about what was entirely new and previously unknown, he often laboured on, when he was ill, with “sighs and tears.” Naturally sensitive, pious, and very amiable, he at one time quite gave up his work under the influence of a remarkable woman, Antoinette Bourignon. She was a wealthy, well-educated person, extremely plain, and who believed that a mission had been given her to preach according to her own fancies, and not in accordance with the general doctrines of the age. She seems to have stimulated Swammerdam to lead a purely religious life, and to give up his studies. It was the age of sects and of intolerance; and possibly the disagreeable reception which this certainly very good woman met with, made the man care more about her peculiar tenets. He began, seriously, to try and sell his collections, made catalogues of his possessions, and corresponded with Antoinette. While various negotiations were pending, Swammerdam published the results of his ten years’ labour and the “Anatomy of the Day Fly,” a great work, and his best. Then he went on a journey into Denmark to use his influence with the king in order to get Antoinette a home in that kingdom, the Lutherans of Holland having ordered her to leave their country. He was not successful; and probably this affair made a great commotion at home. On Swammerdam’s return, his father, enraged at him for his utter carelessness about earning money and his want of application to business, determined to allow him only a small sum of money to live upon. He was in utter despair, for this prevented his following his wish to lead, for the future, a life of meditation and religion. The father died soon afterwards, and a lawsuit was commenced by the family to prevent Swammerdam having his share of the property. This trouble brought on illness, and severe ague followed, and, although recovery took place, the sensitive, able man sank soon afterwards. Swammerdam made an epoch in zoology by showing the value of the microscope, and by his extreme exactitude in descriptions, drawings, and dissections. His contributions to human anatomy alone will always render his name illustrious.
Although everybody must regret that Swammerdam had not good means, and that his work was so sadly brought to a close by poverty and trouble, yet it must be remembered that wealth is not a great incentive to distinction in subjects that require great self-denial, and which are not much valued by what is called public opinion. The temptations incident to, and the real duties of wealth, are as great antagonists of successful scientific research, as poverty. And certainly the frivolity and vice of the wealthier classes of Europe, during the earlier part of the eighteenth century, were not likely to inspire any of their members with a desire for natural science. But some very remarkable instances occurred, in which the genius and determination of some great men prevailed over the intolerance and habits of the age, and enabled them to become men of great mark in zoology and other subjects.
The first to be noticed is René Antoine Ferchault de Réaumur, who was born at Rochelle, in western France, in 1683. Well born, and having wealthy parents, he was well educated, and destined for the law. He did not follow the propensities of the age, but began to study the arts and manufactures of France with great care, and to spend his spare time in natural history researches. From what is known of his career, it is very evident that he had learned chemistry and mineralogy, and that his education had been a most careful and liberal one. His fortune was considerable, and it not being necessary for him to work for his bread, he determined to follow the bent of his inclinations. When twenty years of age, Réaumur went to Paris, and his first essay was in the form of some geometrical work which was read before the Academy of Sciences. At the early age of twenty-four he was admitted a member of that learned and somewhat emotional body, and was a very constant contributor to its publications for fifty years. At first his desire was to improve the arts and manufactures of his native land, and in 1711 he made experiments upon the manufacture of ropes, and he showed that the strength of a cord is less than the sum of the strength of the threads of which it consists, whence it follows that the less a rope is twisted after a certain point, the stronger it is. In 1715 he began to study the process of colouring artificial pearls, and probably it was during these researches that his attention was attracted towards natural history. He found out the nature of the substance which gives the pearly lustre to fish scales, and then he investigated the growth of scales. Following up his subject, he examined into the method of growth of the shells of molluscs. In one of his journeys in Languedoc, he discovered some substances resembling turquoise in colour, and they were used as gems; but he pushed the matter further, and discovered a very remarkable fact. The extinct animal called mastodon, from the peculiar teat-shaped projections on its huge teeth, roamed over Europe in the last geological age, and its teeth, covered with a very strong enamel, have been preserved in strata, or in fissures. Under the influence of the chemical action going on in rocks, the enamel becomes occasionally coloured, so as to resemble a turquoise-coloured porcelain. This was evident to Réaumur, who wrote upon the fact. Other studies took him away from natural history for a while, but they certify to the energy and hard work of the man and his great accuracy. Réaumur’s experiments in the manufacture of iron and steel were of great importance, and it was an attempt to get the art of making steel introduced into France, that urged him on. He made good use of his knowledge, for on publishing his methods of work, the Regent gave him a pension of 12,000 livres a year. Next he discovered the art of tinning iron, and whilst experimenting, Réaumur first noticed that many metallic substances in passing from the heated fluid condition to the cold state, have a tendency to assume particular geometrical or crystalline forms. Among his useful discoveries were plans for the manufacture of porcelain, and they were of great use to France. A thermometer, with a scale of temperature, still largely used in some parts of the world, was invented by him, and he took the freezing and boiling points of water as fixed points, and divided the interval into eighty degrees. The present centigrade thermometer used in France is made on the same plan, but the interval is divided into one hundred degrees. Labouring as a physicist, still all this time Réaumur was doing wonderful work in zoology. He described the means by which many echinodermata—sea-urchins and sea-stars—execute their movements, and discovered the curious manner in which many crustacea, such as crabs and lobsters, throw off their limbs and repair them. But his real and lasting work was on insects, which occupied all his best and later years. Living in perfect quietude, without any great worries, sometimes at his estate at Saurlonge, and at other times at Bercy, near Paris, he worked on, giving all his energies to his subject. His labours, he stated, were published with a view to assist future investigators, and most of them were original. He kept up his pretty country house and garden, and observed the insects and their habits, and especially their methods of changing form. He followed Swammerdam in these investigations, and although there are some differences of opinion between the two great men, still they both made their mark in the investigation of that part of natural history which deals with the progressive development of the minute young to the full-grown creature. Réaumur was sufficiently wealthy to form a large collection of animals, and a very able man, M. Brisson, was employed by him as its curator, and was allowed to describe the quadrupeds and birds. Réaumur did not care so much about classifying insects, as describing their habits and anatomy; but his six great volumes are still most valuable memorials of his conscientious care. He says that the number of observations necessary for a tolerably complete history of so many minute animals is prodigious. When one reflects on all that an accomplished botanist ought to know, it is enough to frighten him. His memory is loaded with the names of twelve or thirteen thousand plants, and he is expected to recall, on occasion, the image of any one of them. There is perhaps not one of those plants but has insects peculiar to itself; and some trees, such as the oak, give sustenance to several hundred different species. And after all, how many are there that do not live on plants? How many species that devour others? How many that live at the expense of other animals? How many species are there, some of which pass the greater part of their time in water, while others pass it entirely there? The immensity of nature’s works is nowhere more apparent than in the prodigious multitudes of these little animals. This being the case, he deems it impossible for any one man to acquire a knowledge of all the insects of even a limited district; therefore, instead of burthening the memory with the characteristic distinctions of these creatures, to the neglect of matters of greater importance, he recommends attention to particular genera, and especially to those which are of most frequent occurrence, that a knowledge of their peculiarities, food, and propagation, and the different forms they assume, may be accurately obtained.
In the first two volumes, Réaumur treats of caterpillars, their changes of form into the chrysalis, and this into the butterfly; about their different kinds and habits, and concerning the other insects which attack them, and live within them, in their early stage.
The third volume includes the description of the habits of the clothes moths, and the plant-lice, or aphides; the fourth treats of gall insects and two-winged flies; the fifth contains the history of bees, and the sixth of wasps and hornets. The natural history of the grasshoppers, crickets, and beetles was to have been written in a seventh volume, but it was never completed. The published volumes contain much very valuable information, and their great merit consists in the wonderful care Réaumur took, in investigating facts and in recording them carefully and systematically. He especially studied the instincts of insects, and thus brought their nervous system into prominent notice, and also the evident connection between the surrounding conditions and the peculiar lives of animals.
Years rolled on and the worthy man became old, but still persisted in his simplicity of life and desire for study. He was so superior in intellect to the class to which he belonged, that he lived free from jealousy and intrigue. Probably few men have led a happier life than Réaumur, and certainly his useful works will last as long as mankind. At the age of seventy-four he met with an accident whilst riding, and died October 18th, 1757. He had no personal vanity, and, being influenced by the true scientific spirit, sought truth and not personal distinction and reward.
Linnæus, whose life has been given under the title of a hero in botanical science, was almost as great a zoologist as botanist and mineralogist. His classification of animals produced as great a change in the direction and possibility of studying zoology, as that of plants did in the case of botany. It led the way, through an artificial system, by which animals could be readily known, to a natural system which united animals not only by their common general shape, but also by the nature, position, and use of their internal organs. His system of naming animals was equal to that of plants, and the reasonable generic and the applicable specific names, going together, stamped the animal with a kind of individuality. Classification, description, and proper naming were the important parts of Linnæus’s zoology.
