LAZZARO, a celebrated naturalist, was born at Scandiano, in the duchy of Modena, on the 12th of January 1729. He began his studies in his native country, and at the age of fifteen, went to Reggio de Modena, where he was instructed in rhetoric and philosophy by the Jesuits, who contended with the Dominicans in order to secure his attachment. His thirst for knowledge determined him to go to Bologna, where his relative Laura Bassi, a woman highly celebrated for her genius, eloquence, and skill in natural philosophy and mathematics, was one of the most distinguished professors of Italy. Under this enlightened guide, he was taught to prefer the study of nature to that of her commentators, judging of the real value of the commentary by its resemblance to the original. He availed himself of the wisdom of that lady's counsels, the happy effects of which he very soon experienced. Spallanzani's taste for philosophy was not exclusive, for he carefully studied his own language, became a proficient in the Latin tongue, and attached himself above every other to the Greek and French. By the advice of a father whom he ardently loved, he applied himself to jurisprudence; but being urged by Antonio Vallisnieri to renounce his vocation, by procuring the consent of his father, he gave himself up to the study of mathematics with more zeal than ever, at the same time devoting himself to the study of languages, both living and dead.

It was not long before he was known all over Italy, and what is seldom the case, his own country first made that estimate of his talents which they justly merited. In the year 1745, he was chosen professor of logic, metaphysics, and Greek, in the university of Reggio, where he taught during ten years, devoting every moment of his leisure to the study and contemplation of the works of nature. The attention of Haller and Bonnet was fixed by his observations on the animalcule of infusions, the latter assisting him in his laudable career, and ever after distinguishing him as one of the learned interpreters of nature. He was invited to the university of Modena in 1760; and some years after he declined to accept of the advantageous offers made to him by the academy of Petersburg, as well as similar ones from Coimbra, Parma, and Cesena. He preferred his native spot, and therefore continued at Modena till the year 1768, and saw raised up by his care a generation of men constituting at that time the glory of Italy, among whom we find Venturi, Belloni, Lucchesini, and Angelo Mazzo.

In 1765, while he resided at Modena, he published his "Saggio di Osservazioni Microscopiche concernenti il Sistema di Needham e di Buffon;" in which he establishes, by a number of the most ingenious and solid experiments, the animality of microscopic animalcula. This work was sent by the author to Bonnet, who drew from it a prediction respecting the future celebrity of Spallanzani, which he lived to see accomplished. This circumstance gave birth to the most intimate friendship, which lasted to the close of life, and constituted their chief happiness. During the same year he published a truly original work, entitled "De Lapidibus ab Aqua resilientibus;" in which he proves, by the most satisfactory experiments, and in opposition to the common received opinion, that what are called ducks and drakes, are not produced by the elasticity of the water, but by the effect naturally resulting from the change of direction experienced by the stone in its movement, after it has struck the water, and has been carried over the hollow of the cup formed by the concussion.

When the university of Padua was re-established upon a larger scale, the Count de Firmian was directed by the empress Maria Theresa, to invite Spallanzani to be professor of Natural History, although the chair was solicited by many celebrated characters. His reputation justified this preference, and immense crowds of students thronged to his lectures. He possessed much ingenuity, and his knowledge was of vast extent: his method was simple, but rigorous in its nature, and what he knew he connected with principles firmly established.

In the year 1776 he published, in two volumes quarto, his work entitled "Opuscoli di Fisica Animale e Vegetabile," containing the explanation of part of the microscopic observations which were previously given to the world. It must be admitted, that the art of accurate observation is one of the most difficult, and it cannot be denied, that it is at the same time the most necessary, and requires a rare combination of talents. These were possessed by Spallanzani in a remarkable degree, as is fully evinced by the researches which his admirable writings have recorded. The polite manner in which he conducted his dispute with Needham respecting the phenomena of generation, secured for him a high degree of applause. On this occasion, he treated of the influence of cold upon animals, and proved that the torpidity of some during winter, does not depend on the impression which the blood may receive from it, since a frog deprived of blood becomes torpid when reduced to the same cold state, by being immersed in ice. Spallanzani travelled through Switzerland and the Grisons in the year 1779, after which he went to Geneva, spending a month with his friends, by whom his conversation was not less admired than his masterly writings. In the year 1780 he published, in two volumes quarto, his "Dissertazioni di Fisica Animale e Vegetabile," in which he unfolded the secrets of the interpretation of two very intricate phenomena, concerning the economy of animals and vegetables. To this study he was led, from some experiments made by him upon digestion; and he repeated the experiments of Reaumur on gallinaceous birds, remarking that the trituration which in this case is favourable to digestion, could not be a very powerful means. He perceived that the gizzard of those birds, by which the stones of fruit are pulverized, did not digest the powder thus formed; it being necessary that it should undergo a new operation in the stomach, previous to its becoming chyle for the production of the blood and other humours. This subject may be regarded as one of the most difficult in physiology, because the observer is always under the necessity of finding his way in the midst of darkness: the animal must be managed with care, that the derangement of the operations may be avoided; and when the experiments are completed with great labour, it is requisite that the consequences be well distinguished. In this work, Spallanzani analyses facts with scrupulousness, in order to ascertain their causes with certainty; comparing nature with his experiments, in order to form a correct judgment respecting them; laying hold of everything essential to them in his observations, and measuring their solidity by the increase or diminution of supposed causes. John Hunter appears to have been greatly hurt by this work; and in the year 1785, he was induced to publish "Some Observations upon Digestion," in which he throws out some bitter sarcasms against the Italian naturalist. Spallanzani took ample revenge by publishing this work in the Italian language, and addressing to Caldani in 1788, "Una Lettera Apologetica in Risposta alle Osservazioni del Signor Giovanni Hunter." Here he exposed with great moderation, but at the same time with logic which nothing could resist, the mistakes and errors of the British physiologist.

The generation of animals and plants is discussed in the second volume of his Dissertazioni; where, by experiments as satisfactory as surprising, he proves the pre-existence of germs to fecundation, shewing also the existence of tadpoles in the females of five different species of frogs, in salamanders, and toads, before their fecundation. He likewise recounts the success of some artificial fecundations upon the tadpoles of those five species, and even upon a quadruped.

In the year 1781, he took the advantage of the academical vacation, for the purpose of making a journey, in order to add to the cabinet of Pavia. In the month of July he set out for Marseilles, where he began a new history of the sea, which presented him with many new and curious facts on numerous genera of the natives of the ocean. He went also to Finale, Genoa, Massa, and Carrara, to make observations on the quarries of marble, held by statuaries in such estimation. He then returned to Spezzia, and brought thence to Pavia a vast number of fishes, which he deposited in the cabinet of that city, wholly collected by himself. With the same view and success he visited the coasts of Istria in 1782, and the Apennine mountains the subsequent year, taking notice of the dreadful hurricanes, and the astonishing vapours by which that year became so noted in meteorology. The emperor Joseph, on examining this cabinet, presented Spallanzani with a gold medal. In 1785, he was offered the chair of natural history by the university of Padua, vacant by the death of Antonio Vallisnieri; but in order to prevent his acceptance of it, his salary was doubled by the archduke, and he went to Constantinople with Zoliani, who had been appointed ambassador from the Venetian republic. He set out on the 21st of August, and on the 11th of October reached the Turkish metropolis, where he remained during eleven months. His attention was fixed by the physical and moral phenomena of this country, which were new even to Spallanzani. He wandered along the borders of the two seas, and ascended the mountains in the vicinity; he paid a visit to the island of Chalki, discovering to the Turks a copper mine, the existence of which they had never once conjectured. In the island of Principi, not far from Constantinople, he discovered an iron mine, of which the Turks were equally ignorant.

A voyage by sea was undoubtedly the safest, but the dangers to which he would be exposed by land were regarded as nothing when contrasted with the idea of being beneficial to science and to man. Having reached Bucharest, Mauroceni, the friend of science, received Spallanzani with marks of distinction, presented him with many rarities which the country produced, and supplied him with horses for travelling, with an escort of thirty troopers, to the confines of his own dominions. The philosopher passed by Hermannstadt in Transylvania, and on the 7th of December 1786, reached Vienna, where he remained during five days, and had two long conferences with the emperor. He was much esteemed by the nobility of that city, and respectfully visited by many literary characters. When he arrived at Pavia, the students advanced from the city-gates to meet him, and testified their joy at his return by repeated acclamations. He was almost instantly drawn to the auditory, and compelled to ascend the chair from which he had been accustomed to deliver his fascinating lectures; but in the midst of these demonstrations of joy and shouts of applause, he requested them to indulge him with that repose in his own house which was now so absolutely necessary. His students this year exceeded 500.

The reputation of Spallanzani was sufficiently brilliant to excite envy and detraction. His discoveries were too original and solid to be successfully disputed; but some of those who could not rival his successful ingenuity, began to call in question his integrity in the management of the museum at Pavia. A judicial investigation completely established the purity of his character; and it must be mentioned to his honour, that he had the fortitude to forget this event. His enemies in general confessed their mistake, renounced their unprovoked animosity, and still hoped to regain a friendship of which they had proved themselves so unworthy.

In 1792 he published at Pavia, in 6 vols. 8vo, his "Viaggi alle due Sicilie, ed alcune parti d'Appennino." Here we meet with what may be denominated a new volcanology. We are instructed how to measure the intensity of volcanic fires, and almost to touch the particular gas which tears those torrents of stone in fusion from the bowels of the earth, and raises them to the top of Mount Etna. This delightful work is closed by some important inquiries into the nature of swallows, the mildness of their dispositions, the rapidity of their flight; discussing the celebrated problem respecting their remaining torpid during the winter season; proving that artificial cold, much more intense than what is ever naturally experienced in our climates, does not reduce these birds to the torpid state.

Things apparently impossible were discovered by Spallanzani. In the year 1795 he made one of this description, which he gave to the world in his "Lettere sopra il Sospetto di un nuovo Senso nei Pippistrelli." In that work we are informed that bats, deprived of sight, act with the same precision in every instance as those which have their eyes; that they shun in the same manner the most trivial obstacles, and also know where to fix themselves when their flight is terminated. Several philosophers confirmed these much exactness, and amidst so many different journeys, he could find sufficient time to write the various books which he published. It may be said of him, that he acquitted himself in his negotiations like a person who had nothing else in his thoughts; and that he wrote like a man who had spent his whole time in his study. His works display a very profound and variegated erudition. The most elaborate of them is entitled, "Dissertationes de Praestantia et Usu Numismatum antiquorum," first printed at Rome in quarto in the year 1664. The best edition, extending to two volumes folio, was printed at London in 1706–17. Another valuable work is his "Orbis Romanus," of which the best edition is that of London, 1704, 4to. He translated the Caesars of Julian into French, and illustrated them with annotations. He likewise contributed notes on Aristophanes, Callimachus, and some other Greek writers, of whom he did not himself publish editions.