Nicolas Steno - Sarcasm Wiki

Contents

1. Overview
2. Etymology
3. Cultural Impact

Blessed

Niels Steensen Vicar Apostolic of Nordic Missions

Portrait of Steno as bishop (1867) See Titiopolis Appointed 21 August 1677 by Pope Innocent XI Term ended 25 November 1686 Predecessor Valerio Maccioni Successor Friedrich von Tietzen [a]

Early life and career

Niels Steensen made his entrance into the world on New Year’s Day, 1 January 1638, according to the Julian calendar , in Copenhagen , the bustling capital of Denmark-Norway . His father, Steen Pedersen, was a respected Lutheran goldsmith who frequently received commissions from the king himself, Christian IV of Denmark . His mother was Anne Nielsdatter. Steensen’s early years were marked by isolation, a consequence of an unknown, debilitating illness he contracted at the tender age of three. This period of solitude, perhaps, fostered the intense observational skills and independent thought that would later define his scientific career. The shadow of mortality loomed large in his childhood; in 1644, his father passed away, and his mother remarried another goldsmith. A more widespread tragedy struck in 1654–1655, when a devastating outbreak of the plague claimed the lives of 240 pupils at his school. Across the street from his home lived Peder Schumacher , a man who, years later, would offer Steensen a prestigious professorship in Copenhagen in 1671. At the relatively young age of 19, Steensen enrolled in the University of Copenhagen , embarking on the rigorous path of medical studies, a decision that would ultimately lead him far beyond the confines of traditional medicine.

Upon the completion of his university education, Steensen, driven by an insatiable curiosity, set out on what would become a lifelong series of travels across Europe. He was, in essence, a man perpetually in motion. His journeys took him through the Netherlands, France, Italy, and Germany, where he sought out and engaged with many of the era’s most prominent physicians and scientists. These encounters were not merely social calls; they profoundly influenced him, honing his critical faculties and reinforcing his commitment to direct observation as the cornerstone of scientific discovery.

At the specific urging of the renowned anatomist Thomas Bartholin , Steensen initially traveled to Rostock , a prominent port city. From there, he proceeded to Amsterdam , a thriving center of intellectual and scientific activity. In Amsterdam, he found lodging and mentorship with Gerard Blasius , a notable anatomist of the time, under whose guidance he delved into the intricacies of anatomy , with a particular focus on the complex lymphatic system . It was during this period, within a mere few months, that Steensen made a significant discovery. However, a rather predictable dispute over credit for this finding erupted between Steensen and Blasius, a testament to the persistent ego and competitive spirit inherent in scientific circles. Despite the contention, Steensen’s name ultimately endured, forever associated with the structure now known as the Stensen’s duct .

Leaving Amsterdam, Steensen relocated to Leiden , another intellectual hub, where he found himself in the company of a remarkable cohort of students and thinkers. Among them were Jan Swammerdam , Frederik Ruysch , Reinier de Graaf , and Franciscus de le Boe Sylvius , a celebrated professor whose influence was widespread. Intriguingly, he also crossed paths with Baruch Spinoza , the controversial philosopher whose radical ideas were challenging the very foundations of contemporary thought. It was in this stimulating environment that Steensen began to openly doubt Descartes’s recently published, and widely accepted, explanation for the origin of tears—a theory that posited they were produced directly by the brain. His skepticism was not idle; it was a prelude to empirical investigation.

In 1665, Steensen accepted an invitation to Paris from Henri Louis Habert de Montmor and Pierre Bourdelot , prominent figures interested in supporting new research. There, he connected with Ole Borch and Melchisédech Thévenot , who were keen to witness demonstrations of his anatomical skills and engage with his novel research. His intellectual journey continued as he traveled through Saumur , Bordeaux, and Montpellier , where he encountered Martin Lister and William Croone . These connections proved vital, as Lister and Croone were instrumental in introducing Steensen’s groundbreaking work to the esteemed Royal Society in London, ensuring his discoveries reached a wider, influential audience.

After his extensive travels through France, Steensen finally settled in Italy in 1666. His initial position was as a professor of anatomy at the prestigious University of Padua . Subsequently, he moved to Florence , where he assumed the role of in-house physician to Grand Duke of Tuscany Ferdinando II de’ Medici . Ferdinando II was a renowned patron of both the arts and sciences, and Steensen had previously met him in Pisa . The Grand Duke’s support provided Steensen with an ideal environment for his research. He was even invited to reside in the opulent Palazzo Vecchio , a privilege that came with the rather charming obligation to contribute to the Grand Duke’s impressive cabinet of curiosities . During this period, Steensen undertook a journey to Rome , where he had the opportunity to meet Pope Alexander VII and the esteemed anatomist Marcello Malpighi , whose work he greatly admired. On his return trip to Florence, while observing a Corpus Christi procession in Livorno , a moment of profound introspection struck him. He found himself questioning the veracity of his own religious beliefs, a seed of doubt that would eventually blossom into a complete transformation of his life’s path.

Scientific contributions

Anatomy

During his intellectually fertile stay in Amsterdam , Steensen made a rather significant anatomical discovery: a previously undescribed structure, which he aptly named the " ductus Stenonis “—the duct of the parotid salivary gland —observed in the heads of sheep, dogs, and rabbits. As previously noted, this discovery led to a rather unedifying dispute with Gerard Blasius over who deserved the credit, a common enough squabble in the competitive world of 17th-century science. However, Steensen’s name, thankfully, remained firmly associated with this structure, which is still known today as the Stensen’s duct . Later, in Leiden , Steensen applied his meticulous observational skills to the heart of a cow. By carefully dissecting and boiling it, he definitively determined that this vital organ was, in fact, nothing more than an ordinary muscle . This was a radical departure from the prevailing, rather poetic, beliefs of the time, which, following ancient authorities like Galenus and even contemporary thinkers like Descartes , considered the heart to be the very center of warmth and life-giving spirit, rather than a mere pump. Steensen’s work was a stark, empirical challenge to centuries of accepted wisdom.

Upon his relocation to Florence , Steensen shifted his anatomical focus to the intricate muscular system and the fundamental nature of muscle contraction . He quickly became an active member of the esteemed Accademia del Cimento , an early scientific society dedicated to experimental inquiry, where he engaged in lengthy and intellectually stimulating discussions with luminaries like Francesco Redi , a pioneer in experimental biology. Alongside Vincenzo Viviani , Steensen proposed a groundbreaking geometrical model of muscles. This model elegantly demonstrated that a contracting muscle changes its shape but, crucially, does not alter its overall volume —a concept that laid important groundwork for later biomechanical studies.

Furthermore, Steensen holds the distinction of being the first scientist to accurately describe the complex lateral line system in fish, a sensory organ that allows them to detect movement and vibration in the surrounding water. One might think such a fundamental observation would have been noted earlier, but then, not everyone possessed Steensen’s peculiar talent for actually seeing what was there.

Paleontology

In October of 1666, an event occurred that would inadvertently propel Steensen into the realm of geological revolution: two fishermen near the town of Livorno hauled in a truly enormous female shark . Ferdinando II de’ Medici , ever the patron of science, wisely ordered the shark’s head to be sent directly to Steensen for examination. Steensen, with his characteristic thoroughness, dissected the head and promptly published his findings in 1667. His observations were startlingly clear: the shark’s teeth bore an uncanny, striking resemblance to certain stony objects that were commonly found embedded within rock formations throughout the region. These objects, his learned contemporaries, clinging to ancient wisdom, were still calling glossopetrae, or “tongue stones.”

The prevailing theories for these “tongue stones” were, to put it mildly, rather imaginative. Ancient authorities, such as the Roman author Pliny the Elder , in his monumental Naturalis Historia , had quaintly suggested that these stones had simply fallen from the sky or, even more fancifully, from the Moon . Other scholars, also deferring to ancient authors, maintained the opinion that fossils were not organic remains but rather grew naturally within the rocks, as if the earth itself had a peculiar capacity for mineral mimicry. Athanasius Kircher , for example, a contemporary polymath, attributed fossils to a “lapidifying virtue diffused through the whole body of the geocosm,” which he considered an inherent characteristic of the earth—a rather convenient Aristotelian explanation that neatly sidestepped any inconvenient questions of origin.

However, the Italian polymath Fabio Colonna had already, by 1616, demonstrated through simple experimentation (burning the material) that glossopetrae were, in fact, organic matter (limestone) rather than mere soil minerals, publishing his findings in his treatise De glossopetris dissertatio. Steensen, building upon Colonna’s crucial work, expanded the theory with a detailed discussion on the observable differences in chemical composition between these fossilized glossopetrae and the teeth of living sharks. He argued, quite presciently, that the chemical composition of fossils could indeed be altered over vast stretches of time without necessarily changing their original form, a concept he explained using the contemporary, and increasingly influential, corpuscular theory of matter .

Steensen’s profound work on shark teeth naturally led him to the much broader and more fundamental question of how any solid object could come to be found embedded within another solid object, such as a rock or a distinct layer of rock. The “solid bodies within solids” that so captivated Steensen’s analytical mind included not only the biological fossils we recognize today but also minerals, crystals, encrustations, veins, and even entire rock layers or strata . His comprehensive geological studies culminated in the publication of his seminal work, 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, with its rather verbose title, marked his final scientific work of significant note. It is worth acknowledging that Steensen was not entirely alone in his deductions; his contemporary Robert Hooke also independently argued that fossils were the undeniable remains of once-living organisms. The truth, it seems, was slowly beginning to pry itself free from the grip of ancient, imaginative conjecture.

Geology and stratigraphy

The year 1669, and specifically the publication of Steensen’s Dissertationis prodromus, stands as a monumental landmark in the history of earth sciences. Within this single work, Steensen articulated four fundamental principles that would come to define the burgeoning science of stratigraphy . These were not mere suggestions but foundational truths, laid out with the precision of a man who had clearly grown weary of unsubstantiated speculation. His exact words, translated, offer a glimpse into the clarity of his thought:

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.” In simpler terms, he observed that in any undisturbed sequence of rock layers, the oldest layer is at the bottom, and the youngest is at the top. It seems obvious now, doesn’t it? But someone had to actually say it.
The principle of original horizontality : “At the time when one of the upper strata was being formed, the lower stratum had already gained the consistency of a solid.” This principle posits that layers of sediment are originally deposited horizontally under the action of gravity. Any tilting or folding observed today must have occurred after the layers were formed. The earth, it turns out, prefers things neat and level, at least initially.
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.” This means that sedimentary layers extend horizontally in all directions until they thin out, pinch out, or encounter a barrier. So, if you see a canyon, you can assume the same layers once connected across the gap.
The principle of cross-cutting relationships : “If a body or discontinuity cuts across a stratum, it must have formed after that stratum.” This is arguably the most straightforward: whatever cuts across something else must be younger than what it cuts. A fault cutting through rock layers, or an igneous intrusion, must have formed after the layers themselves. It’s a basic principle of cause and effect, applied to rocks.

These remarkably clear and concise principles, once articulated, provided a logical framework for understanding the Earth’s history. They were later applied and further extended in 1772 by Jean-Baptiste L. Romé de l’Isle , building directly upon Steensen’s foundational work. Indeed, Steensen’s ideas still form the indisputable basis of modern stratigraphy and were absolutely key in the later development of James Hutton ’s groundbreaking theory of infinitely repeating cycles of seabed deposition, uplifting, erosion, and submersion—the very concept of deep time that revolutionized geological thought.

Crystallography

Beyond the grand sweep of geological formations, Steensen’s meticulous eye also discerned fundamental truths in the seemingly static world of minerals. In his pivotal 1669 book, De solido intra solidum naturaliter contento (the very same Dissertationis prodromus that laid out stratigraphy), Steensen presented the first truly accurate observations on a specific type of crystal. This work led to a foundational principle in crystallography , known simply as Steensen’s law , or, more formally, the law of constancy of interfacial angles or the first law of crystallography.

This elegant law states, with disarming simplicity, that the angles between corresponding faces on crystals are precisely the same for all specimens of the same mineral, regardless of their size or how they were formed. It was an insight into the inherent geometric order of the natural world, a testament to the underlying rules governing atomic arrangement. Steensen’s seminal work, by establishing this constant geometric relationship, paved the way for the more advanced law of rational indices , formulated by the French mineralogist René-Just Haüy in 1801. This fundamental breakthrough, born from Steensen’s keen observation, ultimately formed the basis of all subsequent inquiries into crystal structure and symmetry, proving that even the most seemingly inert substances held profound secrets of order.

Conversion and priesthood

Steensen’s relentlessly questioning mind, which had so effectively dismantled scientific dogma, eventually turned its formidable gaze inward, profoundly influencing his religious views. Having been raised within the established Lutheran faith, he nevertheless found himself interrogating its teachings with the same rigor he applied to anatomical specimens. This internal struggle became particularly acute and pressing when he was confronted with Catholicism during his period of study and residence in Florence . Applying his characteristic analytical approach, he undertook extensive comparative theological studies, delving into the writings of the early Church Fathers and employing his innate observational skills to discern truth. His conclusion, after this period of intense spiritual and intellectual discernment, was that Catholicism, rather than his inherited Lutheranism, offered a more profound and satisfying sustenance for his constant inquisitiveness—a framework that, perhaps, embraced mystery as readily as science embraced empirical fact. Consequently, in 1667, on All Souls’ Day , Steensen formally converted to Catholicism. This pivotal decision was influenced, among others, by Lavinia Cenami Arnolfini, a noblewoman from Lucca who was known for her piety and intellectual depth.

Following his conversion, Steensen’s travels continued, though now imbued with a different spiritual purpose. He journeyed through Hungary and Austria , eventually arriving back in Amsterdam in the spring of 1670. Here, he reconnected with old friends such as Jan Swammerdam and Reinier de Graaf , intellectual giants of the age. He also engaged in deep discussions on both scientific and religious topics with prominent spiritual figures like Anna Maria van Schurman and Antoinette Bourignon , both influential mystics and intellectuals. A particularly poignant quote from a 1673 speech he delivered encapsulates his evolving worldview: “Fair is what we see, Fairer what we have perceived, Fairest what is still in veil.” A rare moment of poetic introspection from a man usually so focused on the concrete. It remains unclear whether he met Nicolaes Witsen , a prominent Amsterdam regent and cartographer, but he certainly read Witsen’s influential book on shipbuilding, indicating his continued, if perhaps more peripheral, engagement with practical sciences. In 1671, he accepted a post as professor of anatomy at the University of Copenhagen , a brief return to his scientific roots and homeland, but he had already promised Cosimo III de’ Medici that he would return to Florence, which he did, to serve as tutor to the Grand Duke’s son, Ferdinando III de’ Medici .

At the beginning of 1675, Steensen made the decisive choice to fully commit to his theological studies, which he had, in fact, begun even prior to his formal conversion, with the explicit goal of ordination to the priesthood. His progress was remarkably swift; after only four intense months of preparation, he was ordained a priest and celebrated his first Mass on 13 April 1675, Easter Sunday, in the magnificent Basilica of the Santissima Annunziata in Florence. He was 37 years old. The renowned scholar Athanasius Kircher , a man who himself straddled the worlds of science and spirituality, expressly inquired about Steensen’s profound reasons for abandoning his scientific pursuits for the priesthood—a question many still ponder. Steensen had, by this point, definitively left the natural sciences behind, dedicating himself entirely to education and theology, thereby becoming one of the most intellectually formidable figures in the Counter-Reformation movement.

His ecclesiastical career advanced rapidly. At the request of Duke Johann Friedrich of Hanover , Pope Innocent XI appointed him Vicar Apostolic for the Nordic Missions on 21 August 1677. Just a month later, on 19 September, he was consecrated titular bishop of Titiopolis by the esteemed Cardinal Gregorio Barbarigo and promptly embarked on his mission to the largely Lutheran North. During his time in Hannover , Steensen engaged in profound intellectual exchanges with Gottfried Leibniz , then the ducal librarian. The two famously debated the controversial philosophy of Baruch Spinoza and his correspondence with Steensen’s own pupil, Albert Burgh , who had also converted to Catholicism. Leibniz, ever the reconciler, even recommended a reunification of the fragmented Christian churches. Steensen diligently worked in the city of Hannover until 1680, striving to strengthen the Catholic presence.

Following the death of John Frederick, Steensen was appointed as Auxiliary Bishop of Münster (Church Saint Liudger) by Prince-Bishop of Paderborn Ferdinand of Fürstenberg on 7 October 1680. This move placed him under the authority of the new prince-elector , Ernest Augustus, Elector of Hanover , who was, inconveniently, a Protestant. It’s said that Augustus’s wife, Sophia of Hanover , found amusement in Steensen’s rather extreme piousness; he had, for example, sold his bishop’s ring and cross, symbols of his office, to provide aid to the needy. He continued, with zealous determination, the work of counter-reform that had been so vigorously initiated by Bernhard von Galen , solidifying his role as a spiritual warrior.

Death

In 1683, Steensen, ever a man of principle, resigned from his position as auxiliary bishop following a disagreement concerning the election of the new bishop, Maximilian Henry of Bavaria . This act of defiance led him to relocate to Hamburg in 1684. There, in a brief but telling return to his former life, Steensen found himself once again immersed in the study of the brain and the complex nervous system, collaborating with an old friend, Dirck Kerckring . It seems old habits, particularly intellectual ones, die hard.

However, his time in Hamburg proved contentious, and when it became clear he was not truly accepted, Steensen was invited to Schwerin . His later years were marked by an almost ascetic devotion to his spiritual duties. He adopted a lifestyle of extreme simplicity, dressing like a pauper in an old cloak and enduring harsh conditions, such as traveling in an open carriage through snow and rain. His self-imposed austerity was profound, as he reportedly lived on little more than bread and beer four days a week, leading to severe emaciation. Once his demanding mission in Schwerin was fulfilled, after years of difficult tasks, he expressed a profound desire to return to the warmer climes of Italy .

Before he could realize this wish, Steensen became gravely ill, suffering from a swelling in his abdomen that worsened day by day. He died in Germany on 25 November 1686, at the age of 48, after a period of intense suffering. In a final testament to his enduring patronage and influence, his corpse was shipped to Florence by Kerckring, at the express request of Cosimo III de’ Medici . He was laid to rest in the Basilica of San Lorenzo , a place of honor close to his powerful protectors, the De’ Medici family. Centuries later, in 1946, his grave was opened as part of the ongoing process towards his beatification, and his corpse was reburied with much ceremony after a procession through the streets of the city, a testament to his lasting impact.

Beatification

Following his death in 1686, Steensen’s profound piety and unwavering virtue did not go unnoticed, particularly within the diocese of Hildesheim , where he was already venerated as a saint. This informal recognition eventually paved the way for a formal evaluation of his life with a view to an eventual canonization . The official process for his canonization began in Osnabrück in 1938, initiating a thorough examination of his life and works by the Church.

In 1953, as a direct part of this beatification process, his grave in the crypt of the Basilica of San Lorenzo in Florence was opened. His remains were then ceremoniously transferred to a fourth-century Christian sarcophagus , a venerable artifact discovered in the Arno river and generously donated by the Italian state. This sarcophagus, containing his remains, was subsequently placed in a lateral chapel within the church, which was fittingly dedicated and renamed the “Capella Stenoniana” in his honor. Finally, on 23 October 1988, Niels Steensen was formally beatified by Pope John Paul II , a recognition of his holiness and an official step towards sainthood. His feast day is now observed annually on 5 December, commemorating the day of his death.

Legacy

Steensen’s extraordinary life and groundbreaking work have continued to be a subject of intense study and fascination, particularly in relation to the profound developments in geology that unfolded in the late nineteenth century. His intellectual shadow, it seems, stretched far beyond his own lifetime, influencing generations of scientists and theologians alike.

His enduring impact is celebrated in numerous ways:

The Steno Museum in Aarhus , Denmark, proudly bears his name. It serves as a vital institution dedicated to preserving and showcasing exhibitions on the history of science and medicine. Beyond its core exhibits, the museum also operates a planetarium , a meticulously cultivated medicinal herb garden, and a series of greenhouses nestled within the Aarhus Botanical Gardens , extending its educational reach.
The prestigious Steno Medal , awarded by the Geological Society of Denmark, stands as a testament to his geological contributions. This honor is bestowed upon prominent geologists who have made significant, lasting contributions to Danish and Greenlandic geology, carrying his name forward in the very field he helped to found.
His name has even reached beyond Earth. Impact craters on both Mars (located at 68°00′S 115°36′W / 68.0°S 115.6°W / -68.0; -115.6 (Steno)) and the Moon have been named in his honor, a cosmic recognition of his earthly insights.
The mineral Stenonite, a crystalline calcium fluoride carbonate, was likewise named in his honour, a fitting tribute given his pioneering work in crystallography.
The Catholic parish church of Grevesmühlen , in North Germany, constructed between 1989 and 1991, is dedicated to Niels Steensen, a modern edifice honoring his spiritual legacy in a region where he once served.
In 1950, the “Niels Steensens Gymnasium,” a Catholic preparatory school, was established in Copenhagen by the Jesuit Order , providing education rooted in the values of inquiry and faith that Steensen exemplified.
The Steno Diabetes Center , a leading research and teaching hospital focused on diabetes, located in Gentofte , Denmark, also carries his name, connecting his anatomical and medical background to contemporary health initiatives.
The Istituto Niels Stensen was founded in 1964 in Florence, Italy, administered by the Jesuit Order and dedicated to his memory, continuing his intellectual and spiritual heritage in the city where he spent so many formative years.
On 11 January 2012, Steensen was prominently commemorated with a Google doodle , appearing on the search engine’s homepage worldwide. This digital tribute celebrated him as the undisputed founder of geology, a somewhat ironic, yet fitting, nod from the digital age to a 17th-century pioneer.

Major works

Steensen’s intellectual output, though sometimes diverted by his spiritual calling, produced several pivotal works that reshaped scientific understanding:

Steensen, Niels / Sténon, Niels. Nicolai Stenonis Observationes anatomicae quibus varia oris, oculorum et narium vasa describuntur, novique salivae, lacrymarum et muci fontes deteguntur, et novum nobilissimi Bilsii de lymphae motu et usu commentum examinatur et rejicitur, Lugduni Batavorum: apud J. Chouet, (1662) via Bibliothèque interuniversitaire de médecine (Paris) [Archived 9 August 2018 at the Wayback Machine ](https://web.archive.org/web/20180809220023/http://www.biusante.parisdescartes.fr/histmed/medica/cote?00523x01 )
Steensen, Niels /Steensen, Niels. Nicolai Stenonis De Musculis et glandulis observationum specimen, cum epistolis duabus anatomicis, Hafniae: lit. M. Godicchenii, (1664). via Bibliothèque interuniversitaire de médecine (Paris) [Archived 9 August 2018 at the Wayback Machine ](https://web.archive.org/web/20180809220023/http://www.biusante.parisdescartes.fr/histmed/medica/cote?00523x01 )
Nicolai Steensennis Elementorum Myologiae Specimen, seu Musculi Descriptio Geometrica, cui accedunt canis carchariae dissectum caput et dissectus piscis ex canum genere… Florentiae : ex typ. sub signo Stellae, (1667) via Bibliothèque interuniversitaire de médecine (Paris) [Archived 9 August 2018 at the Wayback Machine ](https://web.archive.org/web/20180809220023/http://www.biusante.parisdescartes.fr/histmed/medica/cote?00523x01) .
Discours de M. Stenon sur l’anatomie du cerveau…, R. de Ninville (Paris), 1669 via Gallica
Nicolai Stenonis solido intra solidum naturaliter contento dissertationis prodromus … Florentiae : ex typographia sub signo Stellae (1669) , via Google Books The Prodromus of Nicolaus Steno’s Dissertation concerning a solid body enclosed by process of nature within a solid; an English version with an introduction and explanatory notes by John Garrett Winter, New York: Macmillan Company, (1916) via the Internet Archive
Nicolai Stenonis ad novae philosophiae reformatorem de vera philosophia epistola, Florentiae, 1675 (letter to Spinoza)
Nicolai Stenonis Opera philosophica, edited by Wilhelm Maar… vol. I, Copenhagen : V. Tryde, (1910) via Gallica
Nicolai Stenonis Opera philosophica, edited by Wilhelm Maar… vol. II, Copenhagen : V. Tryde, (1910)