Nicolas Steno

Nicolas Steno (Danish: Niels Stensen; latinized to Nicolaus Stenonis) (January 10, 1638 - November 25, 1686) was a pioneer in both anatomy and geology. Already in 1659 he decided not to accept anything simply written in a book, instead resolving to do research himself. He is considered the father of geology and stratigraphy.

Early career

Steno was born in Copenhagen on New Year's Day (Julian calendar), as a son of a Lutheran goldsmith, regularly working for the king, Christian IV of Denmark. Stensen grew up in isolation in his childhood, because of an unknown disease. In 1644 his father died, his mother remarried to another goldsmith. In 1654-1655, 240 pupils of his school died because of the plague. Across the street lived Peder Schumacher, (who would offer Steno a post as professor in Copenhagen in 1671). After completing his university education, he 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. At a time when scientific questions were mostly answered by appeal to ancient authorities, Steno was bold enough to trust his own eyes, even when his observations differed from traditional doctrines, illustrated by the following quote:

Fair is what we see, Fairer what we have perceived, Fairest what is still in veil

On instigation of Thomas Bartholin Steno first travelled to Rostock, then to Amsterdam and studied anatomy under Gerard Blasius, focusing again on the Lymphatic system. 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 is associated with this structure. Within a few months Steno moved to Leiden. There Steno met the students Jan Swammerdam, Frederik Ruysch, Reinier de Graaf, Franciscus de le Boe Sylvius, a famous professor, and Baruch Spinoza. Also Descartes was publishing on the working of the brain, and Steno did not think his explanation of the origin of tears was correct. Steno studied the heart, and found out it was an ordinary muscle.

He travelled to Saumur were he met Melchisédech Thévenot and Ole Borch. Steno travelled to Montpellier, where he met Martin Lister and William Croone, who introduced his work to the Royal Society. In Pisa he met the Grand Duke of Tuscany, who supported arts and science. Steno was invited to live in the Palazzo Vecchio, in return he had to gather a Cabinet of curiosities. Steno first went to Rome and met Alexander VII and Marcello Malpighi. As an anatomist in the hospital Steno focused on the muscular system and the nature of muscle contraction. He also became a member of Accademia del Cimento in Florence. Like Vincenzio Viviani Steno used geometry to show that a contracting muscle changes its shape but not its volume.

Contributions to paleontology and geology

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 Historiae, 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", consided 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 treaty 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. Steno was not the first to identify fossils as being from living organisms; his contemporaries Robert Hooke and John Ray also argued that fossils were the remains of once-living organisms.

Steno, in his Dissertationis prodromus of 1669 is credited with three of the defining principles of the science of stratigraphy: the law of superposition: " the time when any given stratum was being formed, all the matter resting upon it was fluid, and, therefore, at the time when the lower stratum was being formed, none of the upper strata existed"; the principle of original horizontality: "Strata either perpendicular to the horizon or inclined to the horizon were at one time parallel to the horizon"; the principle of lateral continuity: "Material forming any stratum were continuous over the surface of the Earth unless some other solid bodies stood in the way"; and the principle of cross-cutting discontinuities: "If a body or discontinuity cuts across a stratum, it must have formed after that stratum. These principles were applied and extended in 1772 by Jean-Baptiste L. Romé de l'Isle. Steno's landmark theory that the fossil record was a chronology of different living creatures in different eras was a sine qua non for Darwin's theory of natural selection.

Another principle, known simply as Steno's law, or Steno's law of constant angles, states that the angles between corresponding faces on crystals are the same for all specimens of the same mineral, a fundamental breakthrough that formed the basis of all subsequent inquiries into crystal structure.

Religious studies

Steno's questioning mindset 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. Steno converted to Catholicism on All Souls' Day when Lavinia Cenami Arnolfini insisted.

Steno travelled to Hungary, Austria and in Spring 1670 he arrived in Amsterdam. There he met with old friends Jan Swammerdam, Reinier de Graaf. With Anna Maria van Schurman and Antoinette Bourignon he discussed scientific and religious topics. It is not sure if he met Nicolaes Witsen, but he did read his book on shipbuilding. In 1671 he accepted a post in Copenhagen, but promised Cosimo III de' Medici he would return when he would be appointed as the tutor of Ferdinando III de' Medici. In 1675 Steno was back in Florence and ordained a priest. Athanasius Kircher expressly inquired to the reason. Steno had left science and became one of the leading figures in the Counter-Reformation.

In the year after he was made bishop, and probably involved in banning the publications by Spinoza. He came on a mission in Lutheran North on an invitation by John Frederick, Duke of Brunswick-Lüneburg. There he regularly 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 from the city of Hannover until 1680. Steno accepted a position in Münster (Church Saint Liudger) while the new prince-elector Ernest Augustus, Elector of Hanover was a Protestant. Earlier his wife Sophia of Hanover had made fun of Steno's piousness. He sold his bishop's ring and cross to help the needy.

In 1684 Steno moved to Hamburg, after an argument about un-churchlike character of the election of the new bishop, c.q. Maximilian Henry of Bavaria. There he became involved anew in the brain and the nerve system by 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 on beer he became emaciated. When Steno had fulfilled his mission, years with difficult tasks, he wanted go back to Italy. Before he could return Steno became severely ill with his belly swelling daily. Steno died after days of suffering. His corpse was shipped by Kerckring to Florence and buried in the Basilica of San Lorenzo close to his protectors, the De' Medici family. In 1953 his grave was discovered, and the corpse (without the missing skull) was reburied after a procession throught the streets of the city.


Steno's life and work has been studied, in particular in relation to the developments in geology in the late nineteenth century. His piety and virtue have been especially evaluated with a view to an eventual canonization. In 1953 his corpse was exhumed, and reburied in the Capella Stenoniana, but without the missing skull. The Italian state donated a fourth-century Christian sarcophagus that had been found in the river Arno. In 1987, he was declared "beatus" - the first step to being declared a saint - by Pope John Paul II. He is thus now called by Catholics Blessed Nicolas Steno.

  • The Steno Museum in Århus, Denmark, named after Nicolas Steno, holds exhibitions on the history of science and medicine. It also operates a planetarium and a medicinal herb garden.
  • Impact craters on Mars and the Moon are named in his honor.
  • In 1950 the "Niels Steensens Gymnasium", the only Catholic gymnasium in Scandinavia, was founded on a Jesuit monastery in Copenhagen.


Major works

  • Anatomical Observations (1662)
  • Concerning Solids naturally contained within solids (1669)
  • Elementary Mylogical Specimens (1669)
  • Discours de Monsieur Stenon sur L'Anatomie du Cerveau ("M. Steno's lecture on the anatomy of the brain", Paris 1669)


  • The Seashell on the Mountaintop: A Story of Science, Sainthood, and the Humble Genius Who Discovered a New History of the Earth by Alan Cutler, 2003 ISBN 0-525-94708-6
  • Blessed Nicholas Steno (1638-1686). Natural-History Research and Science of the Cross by Frank Sobiech, in: Australian EJournal of Theology, August 2005, Issue 5, ISSN 1448-632 (
  • Steno article at UC Berkeley
  • Niels Stensen

External links

Search another word or see churchlikeon Dictionary | Thesaurus |Spanish
Copyright © 2015, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature