Spallanzani
Achievements: Anticipated Pasteur’s germ theory.
Born: January 12, 1729; Scandiano, Italy
Died: 1799; Pavia, Italy (Aged 70)
Field & Discipline: Science; Biology; Physiology; Physiologist
Education: Reggio Emilia Jesuit College, 1744-49; University of Bologna, 1749-54
Major Work:
“'Dissertazioni di Fisica Animale e Vegetabile” (1780, published in 1803 as “Tracts on the Natural History of Animals and Vegetables,” trans. by J Dalyell)
Life & Times:
After studying law at Bologna University, Spallanzani went to the College of Reggio Emilia in 1755, to teach logic, metaphysics and Greek. Two years later, he was ordained and became lecturer in applied mathematics at the new University of Reggio. In 1760, he took the chair of philosophy and also began to teach Greek. In that same year, he published his first work, a critique of a new Italian translation of Homer's “Iliad,” in the form of three letters to [corresponded with] Algarotti*, Chamberlain to Frederick the Great of Prussia. In the summer of 1761, Spallanzani went to Lake Ventasso and the Appennines, to study the origin of springs and fountains and begin his collection of specimens. The same year, when he came across the work of the French naturalist [work related to] Buffon* and the microscopist John Tuberville Needham, he began to look at the phenomena of life and reproduction.
In 1763, Spallanzani began work at the University of Modena as Professor of Physics. His first biological work, published in 1765, was an attack on the theory of spontaneous generation proposed by Buffon and Needham fifteen years earlier. They had both theorised that all living things contained, in addition to inanimate matter, ‘vital atoms’ responsible for all physiological activity. After death, they believed, these vital atoms passed into the soil and were taken up by plants, in an act of spontaneous generation. Spallanzani repeated Needham’s experiments, using a better microscope and confirmed the view of [confirmed work of] Leeuwenhoek*, published a hundred years earlier, that living organisms didn’t happen spontaneously. After hundreds of experiments with infusions of vegetables or cereal seeds, Spallanzani finally showed that a broth, boiled until sterile and then hermetically sealed, remained free of microorganisms until air was allowed in, when microorganisms would develop. Spallanzani concluded that microscopic life forms in pond water and other preparations were living organisms introduced from the air and that Needham's views were wrong. He published his essay on the subject, “Saggio di Osservazioni Microscopiche” in 1765. Spallanzani’s work on heat sterilization also inspired [inspired] Appert*, who developed a heat technique to preserve food in 1810.
Spallanzani sent his work to [sent material to] Voltaire* and the Swiss naturalist and philosopher [sent material to] Bonnet*, who encouraged him to study reproductive phenomena in animals and plants. In 1768, he published the results of his extensive regeneration and transplantation experiments. In this work, Spallanzani demonstrated regeneration in earthworms, slugs, snails, salamanders, toads and frogs and reached a number of general conclusions. He showed that the lower animals had a greater regenerative power than the higher orders, that young individuals had a greater capacity for regeneration than the adults of the same species and, except in the simplest animals, it was the outer parts, not the internal organs, that regenerated. Spallanzani’s findings were given a mixed reception, from surprised interest to complete disbelief, particularly his claims about decapitated snails growing new heads. Some scientists, particularly Voltaire, tried, without success, to repeat his experiments, but others, including Bonnet, [work related to] Senebier*, [work related to] Bassi* and [work related to] Lavoisier* proved him right.
In the same year that he revealed his regenerative results, Spallanzani published details of an investigation that he had carried out on the circulation of the blood through the lungs and other organs, which he addressed to the great physiologist [sent material to] Haller*. The following year, he was given the chair of Natural History at the University of Pavia, where he stayed for the rest of his life. In 1780, Spallanzani announced the results of a series of experiments on digestion, in which he proved that gastric juice contained the key digestive elements and that the digestive juices were made up of individual chemicals that were suited to particular foods.
Spallanzani supported the view that spermatozoa were parasites within the semen and demonstrated for the first time that contact between egg and semen was essential for the development of a new animal. He then showed that the more semen was filtered, the less effective it became. Spallanzani’s conclusion was that the protein and fat forming the bulk of the semen were essential and he continued to regard the spermatozoa within the sperm as inessential parasites. He carried out the first artificial insemination of a viviparous animal, when he produced three pups from a spaniel bitch.
He went on a number of scientific expeditions to Switzerland, the Mediterranean and the Adriatic and spent time in Constantinople and Sicily, where he studied not just the flora and fauna, but the geology, geography, meteorology as well and, in Sicily, the vulcanology. In the last five years of his life, Spallanzani did experiments on microscopic animals and plants and studied the electric charge of the torpedo fish and the sense organs in bats. About 15 years after his death, he was immortalized as the genius-wizard “Professor Spalanzani” in one of [immortalized by] Hoffmann's* most famous tales: “The Sandman.”
Extra Connections: His work related to that of the French mathematician [work related to] Maupertuis* and the German physician [work related to] Schonlein* , who carried out important work on disease transmission.
He anticipated [anticipated] Pasteur’s* germ theory.
Assessment: Famous in the eighteenth century for his innovative experimental methods.
Oneliner: Lazzaro Spallanzani, discoverer of early germ theory
Language: Italian.
Father: Gianniccolo Spallanzani
Mother: Lucia Zigliani
Siblings: Two sisters, one of which, Marianna, was a naturalist and one
brother, Niccolo, a lawyer and agronomist
Spouse: None
Children: None
Bibliography:
- Gasking, Elizabeth B., The Rise of Experimental Embryology, 1970.