Nicolas Steno (Danish: Niels Steensen; Latinized to Nicolaus Steno or Nicolaus Stenonius[notes 2]; 1 January 1638 – 25 November 1686[NS: 11 January 1638 – 5 December 1686]) was a Danishscientist, a pioneer in both anatomy and geology who became a Catholic bishop in his later years. Steno was trained in the classical texts on science; however, by 1659 he seriously questioned accepted knowledge of the natural world. Importantly he questioned explanations for tear production, the idea that fossils grew in the ground and explanations of rock formation. His investigations and his subsequent conclusions on fossils and rock formation have led scholars to consider him one of the founders of modern stratigraphy and modern geology.
Nicolas Steno was born in Copenhagen on New Year's Day 1638 (Julian calendar), the son of a Lutherangoldsmith who worked regularly for King Christian IV of Denmark. He became ill at age three, suffering from an unknown disease, and grew up in isolation during his childhood. In 1644 his father died, after which his mother married another goldsmith. In 1654–1655, 240 pupils of his school died due to the plague. Across the street lived Peder Schumacher (who would offer Steno a post as professor in Copenhagen in 1671). At the age of 19, Steno entered the University of Copenhagen to pursue medical studies. After completing his university education, Steno set out to travel through Europe; in fact, he would be on the move for the rest of his life. In the Netherlands, France, Italy and Germany he came into contact with prominent physicians and scientists. These influences led him to use his own powers of observation to make important scientific discoveries.
During his stay in Amsterdam, Steno discovered a previously undescribed structure, the "ductus stenonianus" (the duct of the parotid salivary gland) in sheep, dog and rabbit heads. A dispute with Blasius over credit for the discovery arose, but Steno's name remained associated with this structure known today as the Stensen's duct. In Leiden, Steno studied the boiled heart of a cow, and determined that it was an ordinary muscle and not the center of warmth as Galenus and Descartes believed.
Steno was the first to describe the lateral line system in fishes.
In October 1666 two fishermen caught a huge female shark near the town of Livorno, and Ferdinando II de' Medici, Grand Duke of Tuscany, ordered its head to be sent to Steno. Steno dissected the head and published his findings in 1667. He noted that the shark's teeth bore a striking resemblance to certain stony objects, found embedded within rock formations, that his learned contemporaries were calling glossopetrae or "tongue stones". Ancient authorities, such as the Roman author Pliny the Elder, in his Naturalis Historia, had suggested that these stones fell from the sky or from the Moon. Others were of the opinion, also following ancient authors, that fossils naturally grew in the rocks. Steno's contemporary Athanasius Kircher, for example, attributed fossils to a "lapidifying virtue diffused through the whole body of the geocosm", considered an inherent characteristic of the earth – an Aristotelian approach. Fabio Colonna, however, had already shown in a convincing way that glossopetrae are shark teeth, in his treatise De glossopetris dissertatio published in 1616. Steno added to Colonna's theory a discussion on the differences in composition between glossopetrae and living sharks' teeth, arguing that the chemical composition of fossils could be altered without changing their form, using the contemporary corpuscular theory of matter.
Steno's work on shark teeth led him to the question of how any solid object could come to be found inside another solid object, such as a rock or a layer of rock. The "solid bodies within solids" that attracted Steno's interest included not only fossils, as we would define them today, but minerals, crystals, encrustations, veins, and even entire rock layers or strata. He published his geologic studies in De solido intra solidum naturaliter contento dissertationis prodromus, or Preliminary discourse to a dissertation on a solid body naturally contained within a solid in 1669. This book was his last scientific work of note.[notes 3] Steno was not the first to identify fossils as being from living organisms; his contemporaries Robert Hooke and John Ray, as well as Leonardo da Vinci a century earlier also argued that fossils were the remains of once-living organisms.
Geology and stratigraphy
De solido intra solidum naturaliter contento dissertationis prodromus (1669)
Steno, in his Dissertationis prodromus of 1669 is credited with four of the defining principles of the science of stratigraphy. His words were:
the law of superposition: At the time when a given stratum was being formed, there was beneath it another substance which prevented the further descent of the comminuted matter and so at the time when the lowest stratum was being formed either another solid substance was beneath it, or if some fluid existed there, then it was not only of a different character from the upper fluid, but also heavier than the solid sediment of the upper fluid."
the principle of lateral continuity: "At the time when any given stratum was being formed it was either encompassed on its sides by another solid substance, or it covered the entire spherical surface of the earth. Hence it follows that in whatever place the bared sides of the strata are seen, either a continuation of the same strata must be sought, or another solid substance must be found which kept the matter of the strata from dispersion."
the principle of cross-cutting relationships: "At the time when any given stratum was being formed, all the matter resting upon it was fluid, and, therefore, at the time when the lowest stratum was being formed, none of the upper strata existed."
Steno gave the first accurate observations on a type of crystal in his 1669 book "De solido intra solidum naturaliter contento". The principle in crystallography, known simply as Steno's law, or Steno's law of constant angles or the first law of crystallography, states that the angles between corresponding faces on crystals are the same for all specimens of the same mineral. Steno's seminal work paved the way for the law of the rationality of the crystallographic indices of French mineralogist René-Just Haüy in 1801. This fundamental breakthrough formed the basis of all subsequent inquiries into crystal structure.
Steno's questioning mind also influenced his religious views. Having been brought up in the Lutheran faith, he nevertheless questioned its teachings, something which became a burning issue when confronted with Roman Catholicism while studying in Florence. After making comparative theological studies, including reading the Church Fathers and by using his natural observational skills, he decided that Catholicism, rather than Lutheranism, provided more sustenance for his constant inquisitiveness. In 1667, Steno converted to Catholicism on All Souls' Day when Lavinia Cenami Arnolfini, a noblewoman of Lucca, insisted.
In the year after he was made bishop, he was probably involved in the banning of publications by Spinoza, There he had talks with Gottfried Leibniz, the librarian; the two argued about Spinoza and his letter to Albert Burgh, then Steno's pupil. Leibniz recommended a reunification of the churches. Steno worked at the city of Hannover until 1680.
In 1683, Steno resigned as auxiliary bishop after an argument about the election of the new bishop, Maximilian Henry of Bavaria and moved in 1684 to Hamburg. There Steno became involved again in the study of the brain and the nerve system with an old friend Dirck Kerckring. Steno was invited to Schwerin, when it became clear he was not accepted in Hamburg. Steno dressed like a poor man in an old cloak. He drove in an open carriage in snow and rain. Living four days a week on bread and beer, he became emaciated.[notes 4] When Steno had fulfilled his mission, some years of difficult tasks, he wanted to go back to Italy. Before he could return, Steno became severely ill, his belly swelling day by day. Steno died in Germany, after much suffering. His corpse was shipped to Florence by Kerckring upon request of Cosimo III de' Medici and buried in the Basilica of San Lorenzo close to his protectors, the De' Medici family. In 1946 his grave was opened, and the corpse was reburied after a procession through the streets of the city.
After his death in 1686, Steno was venerated as a saint in the diocese of Hildesheim. Steno's piety and virtue have been evaluated with a view to an eventual canonization. His canonization process was begun in Osnabrück in 1938. In 1953 his grave in the crypt of the church of San Lorenzo was opened as part of the beatification process. His corpse was transferred to a fourth-century Christian sarcophagus found in the river Arno donated by the Italian state. His remains were placed in a lateral chapel of the church that received the name of "Capella Stenoniana". He was declared "beatus" — the third of four steps to being declared a saint — by Pope John Paul II in 1988. He is thus now called by Catholics Blessed Nicolas Steno. His feast day is 5 December.
Steno's life and work has been studied, in particular in relation to the developments in geology in the late nineteenth century.
^Friedrich von Tietzen, called Schlüter (1626–1696)
^Also known as Nikolaus or Nils Steensen, Stens. Steno took his surname from his father's given name. In accordance with the academic customs of his time, Nicolas latinized the Danish form of his name Niels Ste(e)nsen as Nicolaus Stenonis. The English form, Steno, is due to an error in parsing the Latin.
^Leibnitz came to know and esteem Steno in Hannover and expressed deep regrets that Steno had abandoned his earlier studies.
^On the other days there were never more than four courses plus a dessert, even though noblemen from the court often dined with him.
^Janker, Stephan M. (1990). Die Bischöfe des Heiligen Römischen Reiches : ein biographisches Lexikon (in German). Berlin: Duncker und Humblot. p. 516. ISBN978-3-428-06763-3.
Scherz, G. (2002). "Stensen, Niels, Bl.". In Catholic University of America. The New Catholic Encyclopedia. Volume 13 – Seq to The. Catholic University Press/Thomas Gale. pp. 508–509. ISBN0-7876-4017-4.
Cutler, Alan (2003). The Seashell on the Mountaintop: A Story of Science, Sainthood, and the Humble Genius Who Discovered a New History of the Earth. New York: Dutton. ISBN0-525-94708-6.
Tubbs, R. Shane; Mortazavi, Martin M.; Shoja, Mohammadali M.; Loukas, Marios; Cohen Gadol, Aaron A. (2010). "The bishop and anatomist Niels Stensen (1638–1686) and his contributions to our early understanding of the brain". Child's Nervous System (in Dutch). 27: 1–6. doi:10.1007/s00381-010-1236-5.
Tubbs, R. Shane; Gianaris, Nicholas; Shoja, Mohammadali M.; Loukas, Marios; Cohen Gadol, Aaron A. (2010). ""The heart is simply a muscle" and first description of the tetralogy of "Fallot". Early contributions to cardiac anatomy and pathology by bishop and anatomist Niels Stensen (1638–1686)". International Journal of Cardiology. 154 (3): 312–5. doi:10.1016/j.ijcard.2010.09.055. PMID20965586.