Electronic edition published by Cultural Heritage Langauge Technologies (with permission from Charles Scribners and Sons) and funded by the National Science Foundation International Digital Libraries Program. This text has been proofread to a low degree of accuracy. It was converted to electronic form using data entry.
STENSEN, NIELS, also known as Nicolaus Steno
(b. Copenhagen, Denmark, 1%6111 January 1638; d.
Schwerin, Germany, 25 November/5 December
1686), anatomy, geology, mineralogy.
Stensen was the son of Sten Pedersen, who
came from a family of preachers and was a goldsmith.
After graduating from the Liebfrauenschule,
Stensen entered the University of Copenhagen in
1656. There he studied medicine and came under
the special influence of Simon Paulli and Thomas
Bartholin. The customary study journey took him
at the end of March 1660 to Amsterdam and, on
27 July for his matriculation, to the University of
Leiden, from which, after three years of diligent
research, he was called home because of the death
of his stepfather.
The University of Copenhagen failed to enlist
Stensen's services, and so he went to Paris; he is
known to have been there as late as November
1664 and to have received on 4 December his M.D.
from the University of Leiden in absentia. After a
fruitful year in the circle of Thévenot, the king's
chamberlain, Stensen went in the autumn of 1665
to Montpellier; and from there he went to Pisa,
where he stayed until the beginning of March 1666.
He remained in Tuscany until July 1668, mostly
at the court of Grand Duke Ferdinand II in
Although he came from a deeply religious Lutheran
family, Stensen became a convert to Catholicism
on All Souls' Day 1667 during a period of
research in anatomy and geology. This research
was interrupted, probably by a summons to Denmark,
from August 1668 to June 1670. Upon his
return to Florence, Stensen again worked in Tuscany,
exploring two alpine grottoes at Lake Garda
and Lake Como for the Accademia del Cimento.
Following a call to return to Denmark as royal
anatomist, Stensen arrived at Copenhagen on 3
July 1672. Here, mostly for a circle of interested
friends, he held a series of anatomical demonstrations.
But he left his native city on 14 July 1674 to
return to Florence, where he was consecrated a
priest, probably in the middle of April 1675, and
where he worked for two years as educator and
tutor of the crown prince. Upon the invitation of
Duke Johann Friedrich of Hannover, he went to
Rome, where he was appointed apostolic vicar of
northern missions by Pope Innocent XI on 21
August 1677 and was consecrated titular bishop of
Titiopolis on 19 September. Until the end of June
1680, he ministered to the scattered remnants of
Catholicism in northern Germany, Denmark, and
Norway. Then after the death of the duke, he was
appointed assistant bishop of Münster in West-phalia,
where he was very active. On 1 September
1683 he left the city in protest against the simoniac
election of the bishop's successor. After two years
of apostolic activity in Hamburg and Schwerin, he
died in acute pain from gallstones.
Two educational influences upon Stensen's youth
deserve special attention. Since his father's goldsmith
shop was near the Round Tower, his scientific
interest may have been directed at an early
age into technical-mathematical channels to which
he wished to return even in the midst of his first
period of biological investigations in Leiden. He
was interested in minerals and metals; in lenses and
light refraction; and in telescopes, microscopes,
and thermoscopes. Thomas Walgesten, the inventor
of the laterna magica, belonged to the circle of his
acquaintances. Stensen, of course, knew the medical
authors Thomas Bartholin, Pierre Borel, Henricus
Regius, Paracelsus, Helmont, and Santorio.
Stensen's physical-mathematical interests are indicated
by his reading not only the works of Galileo
(Sidereus nuncius ) and Kepler (De nive
sexangula ) but also those of Gassendi,
Clavius, Gaspar Schott, Snel, and Varenius. Stensen
had a precocious desire for methodically