Darwin’s Botanists: In the Family

Frontispiece for Eramus Darwin’s The Botanic Garden, Biodiversity Heritage Library

In this series of post’s I’ll be discussing key botanists who influenced Charles Darwin’s work:  John Stevens Henslow, Joseph Dalton Hooker, and Asa Gray.  But first I’ll look at those closer to home who were important to Darwin’s development as a naturalist.  The most obvious is his grandfather, Erasmus Darwin, a physician with broad interests including botany.  He worked with two others in his town of Litchfield to translate some of Linnaeus’s work, and after that wrote a volume of poetry, The Love of Plants, as an introduction to the Linnaean classification system.  It was well-received and was followed by The Economy of Vegetation; the two were then published together as The Botanic Garden.  There are hints of evolutionary thinking in them, but are more overt in Zoonomia, a two-volume medical work with a chapter on generation that presents a somewhat Lamarckian view of species change.  Erasmus died before Charles Darwin was born, so most of his grandfather’s influence on him was through his writings.  By the time Charles was studying at Cambridge, he was aware of Erasmus’s ideas as well as those of Lamarck.

Darwin’s father Robert was also a physician interested in botany, though not a writer.  However, he took pleasure in gardening with his children.  This is probably how Charles was first introduced to nature, and he early had a fascination with plants and animals, with closely observing nature as every good gardener must.  Since it’s impossible to garden without encountering insects, it was probably in working with his father that Charles developed his interest in insects and became a collector.  Robert also kept a notebook where he recorded phenological events such as first flowerings, something that his son and grandsons also did.  At one point Robert set the young Charles the task of counting the number of peony blooms each year.  What I find interesting about this is that the number varied from 160 to 363, an impressive display.

Robert Darwin hoped that Charles would follow in his father’s and grandfather’s footsteps, not only in gardening but in becoming a physician as Robert’s older son, Erasmus, did.  But after spending two years at the University of Edinburgh studying medicine, Charles had to break it to his father that he was not cut out to be a physician (Browne, 1995).  It was a tremendous relief to be free of that burden, and Robert sent his son off to Cambridge to become a clergyman, a profession that was at the time full of naturalists.  At Cambridge Darwin met the cleric/professor of botany, John Stevens Henslow, but that is the story of the next post.

While at the university, Darwin became friendly with a cousin, William Darwin Fox, who was also interested in natural history, particularly entomology.  It was Fox who introduced Darwin to the wonders of beetles.  This was a time when divisions between biological disciplines was permeable so in hunting for beetles it was impossible not to take an interest in birds, plants, and even aquatic life that filled the wetlands around Cambridge.  After acquiring a microscope from a friend, Darwin became fascinated by the world of aquatic invertebrates and studied their reproductive cycles.  There seemed to be no aspect of natural history that didn’t engage him.  At the end of his time at Cambridge, he went on a geological fieldtrip to Wales with Adam Sedgewick, professor of geology, and there he made what is considered his oldest existing herbarium sheet. 

After Cambridge came Darwin’s five years of travel on the Beagle which involved collecting specimens that he sent back to Henslow.  In fact, Henslow served as receiver for all eight shipments of plants, animals, fossils, and rocks that Darwin had amassed.  I’m skipping forward very rapidly, but much of this story is familiar to many of you, and for those who want more detail, Janet Browne’s two-volume biography is a joy to read (1995, 2002).  As he was creating the first draft of his theory of species change in 1838, Darwin decided to marry Emma Wedgewood.  They had 10 children, seven of whom lived to adulthood, and all were assistants in his work to a greater or lesser extent.  They pitched in with the endless experiments Darwin devised at Down House, their home in the country outside London.  As they got older, they took on more responsibility.  His daughter Henrietta was his editor and proofreader, and his sons George and William made many of the drawings for his botanical works.  Darwin even engaged George Sowerby, a member of a distinguished family of natural history artists, to teach engraving to George Darwin, whose daughter became the famous printmaker Gwen Raverat.  She also wrote a great book on growing up a Darwin in Cambridge (1952).

Francis Darwin was the son who was most involved in Darwin’s later scientific work, particularly in investigating plant movements and phototropism.  Francis’s first wife died in childbirth.  To ease his grief, his parents urged him to move back to Down House with his infant son.  This is when his collaboration with his father became particularly close, and they co-authored The Power of Movement in Plants, published in 1880, two years before Charles’s death.  Francis also edited collections of his father’s letters.  So even without going outside his family, Darwin received a great deal of inspiration and assistance from those related to him, across the generations.  In the following posts, I’ll discuss some of those outside the family who were also important to his botanical work.

References

Browne, J. (1995). Charles Darwin: Voyaging. Princeton, NJ: Princeton University Press.

Browne, J. (2002). Charles Darwin: The power of place. Princeton, NJ: Princeton University Press.

Raverat, G. (1952). Period Piece: A Cambridge Childhood. London: Faber & Faber.

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The Linnaean Apostles: Carl Thunberg

4 Thunbergia capensis LINN 815.1

Thunbergia capensis (LINN 815.1) from the herbarium of the Linnean Society, London

This is the last in a series of posts (1, 2, 3) on those who studied with Carl Linnaeus and then became his “apostles,” spreading his taxonomic system and traveling the globe searching for new species for him to identify.  The subject here is Carl Peter Thunberg (1743-1828) whose explorations took place so late in Linnaeus’s life that most of his collection did not reach Sweden until after the latter’s death in 1778.  Thunberg eventually became professor of botany at the University of Uppsala, a chair that had been passed on to Carl Linnaeus the Younger who died five years after his father.  Thunberg held the position for 44 years during which he used his professor’s taxonomic system to name and describe the many plants discovered on his travels.

Attending the University of Uppsala, Thunberg studied with Linnaeus, who recognized his student’s abilities and arranged a grant for him to study in the Netherlands and France.  In Holland Thunberg met the botanist Johannes Burman, a friend of Linnaeus from the latter’s time in that country (see earlier post).  Burman and his son Nicolas, also a botanist and a student of Linnaeus, were so impressed with Thunberg that they encouraged him to seek employment as a physician with the Dutch East India Company.   In the meantime, Thunberg went on to Paris where he spent a year studying with Bernard Jussieu, a noted plant taxonomist and teacher.  This gave him an opportunity to examine the extensive collections in the Paris herbarium, something that Linnaeus had done years before.  When Thunberg returned to the Netherlands, he was offered the position of surgeon at the Dutch outpost in Japan.  Since the Japanese had a strict agreement that only the Dutch would be allowed there, Thunberg had to learn the language before arriving.  He did this while staying in the Dutch colony in Cape Town, South Africa for almost three years.

This was a wonderful opportunity for Thunberg to investigate the rich Cape flora.  Linnaeus was thrilled with this, since his interest in South African flora dated back to his time in the Netherlands, where he studied Paul Hermann’s herbarium, the first organized collection from the area.  Thunberg found traveling companions for his explorations including Anders Sparrman another Linnaean apostle who had already collected in China and then traveled with James Cook on his second circumnavigation of the globe.  Thunberg was wary of Sparrman usurping his collections, so he felt more comfortable traveling on brief trips with the British botanist Francis Masson, who was collecting for the Royal Botanic Gardens, Kew.  Thunberg also made three longer collecting tours that lasted for months and covered 5,000 km.  He took extensive notes, not only on plants but on local customs and information on the Hottentot language (Fraser & Fraser, 2011).

After mastering Dutch, Thunberg sailed for Japan.  He stayed at Deshima, an island in Nagasaki constructed as a Dutch port where the Dutch were held during their stays in Japan.  While biding his time in Deshima, Thunberg would go through the fodder brought in for animals to find interesting seeds to plant.  Access to the rest of the country was forbidden, except for a yearly journey to the capital at Edo to pay homage to the emperor.  This trip took a couple of months and involved a large entourage paid for by the Dutch, but with only a few Dutch allowed to participate, including the colony’s surgeon, Thunberg.  He tried to do as much collecting as possible, relying on Japanese he had befriended to find plants for him.  One thing that disappointed him was that he found few roadside weeds such as he would have seen in Europe because the Japanese worked diligently to eradicate all weeds (Vande Walle & Kasaya, 2001).

Thunberg definitely made the most of his time in Japan, and the Japanese who had an interest in natural history learned from him.   He remained in Japan for about 18 months and then traveled to Batavia in what is now Indonesia collecting there for six months and in Ceylon (now Sri Lanka) before returning to the Cape.  After landing in Holland, he spent two months in England.  He managed to visit another Linnaean student, Daniel Solander, who was working at the British Museum (see last post), and study the collections Solander and Joseph Banks had made in Asia.  Thunberg finally returned to Sweden in 1779.  He had been appointed lecturer in botany at the University of Uppsala, a position he held until Linnaeus’s son died in 1783, then the master’s chair finally belonged to Thunberg.  In 1784 he produced his Flora Japonica, and at the turn of the century, published a series of illustrations on plants described in the flora.  He described his African plants many years later in Flora Capensis of 1807.  Both his floras were long in use, not replaced by new publications for decades.  Thunberg’s herbarium, including the Japanese collection, is preserved in the Museum of Evolution at the University of Uppsala.  Its value is indicated by the fact that it is kept in fire-proof vault along with other treasures of the collection, among them the herbarium of Joachim Burser.  The latter is important because it was used by Caspar Bauhin in creating his Pinax Theatri Botanici, one of the early and great compendia of known plants.  Linnaeus referenced the collection as a guide to the plants that Bauhin had used in writing his descriptions.  So even though Linnaeus’s own herbarium is not in Uppsala, but in the Linnaean Society of London, there are still extraordinary botanical treasures at his university.

References

Fraser, M., & Fraser, L. (2011). The Smallest Kingdom: Plants and Plant Collectors at the Cape of Good Hope. Richmond, UK: Kew Publishing.

Vande Walle, W. F., & Kasaya, K. (Eds.). (2001). Dodonæus in Japan: Translation and the Scientific Mind in the Tokugawa Leuven: Leuven University Press.

The Linnaean Apostles: Daniel Solander

3 Solandra tridentata LINN 332a.2

Solandra tridentata (LINN 332.2) from the herbarium of the Linnean Society, London

In the last post I discussed one of Carl Linnaeus’s students, Peter Forsskål, who never returned from his expedition to the Near East.  Daniel Solander (1733-1782) traveled farther and also lived to study the fruits of his exploration.  He was born in Lapland and, not surprisingly, studied in Uppsala where he was considered Linnaeus’s favorite pupil.  When British botanists asked Linnaeus to send someone to England to boost the use of Linnaean taxonomy, Solander was chosen.  He left in 1760 and never again lived in Sweden.  At first, he spent time reorganizing the herbaria of wealthy patrons such as the Duchess of Portland and Peter Collinson, who was one of those who had encouraged Linnaeus to send an “apostle” to England.  He was influential in British botanical circles as a member of the Royal Society, a trustee of the newly formed British Museum, and a patron of the American nurseryman John Bartram.  Solander sent specimens from Collinson and others on to Linnaeus.  When the British Museum was looking for someone to care for the herbarium of Hans Sloane, the donor of the museum’s founding collection, Collinson asked Lord Bute, then Prime Minister, to suggest Solander to the King as the ideal choice (Rose, 2018).  This is a fascinating, though tiny, piece of history because all of the individuals involved were interested enough in plants that the care of a plant collection would be discussed at the highest government levels.

Solander began working at the museum in 1763 and set about giving the plants in the herbarium Linnaean names without disrupting the physical order of its 265 bound volumes.  This was a compromise that would allow those not familiar with the new system to still find plants in the collection using Sloane’s system, which was essentially an annotated copy of John Ray’s Historia Plantarum in which Sloane or his botanical curator had written the volume and folio numbers for each species, noting new species when necessary.  Solander began with the first volumes of the herbarium, those containing the collections Sloane had made while he served as physician to the Duke of Albemarle on the island of Jamaica in 1687-1688.  Among the 800 species were hundreds of new ones that Sloane described in his two volume Natural History of Jamaica (1702-1727).  Solander wrote the names on labels that he added to Sloane’s sheets, but retained the older labels, an approach that not been taken by many earlier botanists though later became the norm.

While at the museum, Solander began to receive visits from a young botanical enthusiast, Joseph Banks, heir to a large fortune who had attended but not graduated from the University of Oxford.  He supplied Solander with an unmarked copy of the Sloane Jamaica volumes to annotate.  This was a good way to keep track of the Jamaican species.  When Solander moved on to the rest of the collection, he used slips of paper to record the new names and crossreferenced them with the volume and folio numbers.  He also annotated a copy of Linnaeus’s Species Plantarum.  In this way, the collection was “modernized” without being rearranged.  This went on until 1768, when Solander took on a very different kind of challenge.

Banks had convinced the British Admiralty to make him part of the round-the-world expedition to be led by James Cook on the Endeavor.  It’s major aim, and the publicized one, was to observe the transit of Venus across the sun, which would take place on June 3, 1769.  However, Cook was also instructed to visit Australia, acquiring as much navigational and geographic information for future use in possible colonization (O’Brian, 1993).  Banks, at his own expense, put together a team to study natural history.  It included Solander, Herman Spöring of Finland as secretary, two artists, and two servants.  Banks paid to outfit the ship for his group as well as for scientific instruments and other supplies for preserving specimens and even for growing plants.  There is obviously a lot to this story, but for now I will stick to Solander and plants.

Apparently Banks and Solander made a good team.  They developed a system for dealing with the huge amount of material they collected, in all, about 30,000 plant specimens.  They would return to base each day, give the artist Sydney Parkinson the fresh material to sketch and make color notes, while they, with Spöring’s help, wrote up their notes.  The plants were pressed, though at times, as when they reached Australia, their system couldn’t keep up with collecting.  Plants weren’t drying fast enough, so the pair laid them out on deck on sails during the day.  Needless to say, this massive collection proved daunting to tackle for publication.  Banks and Solander worked on it for years, with engravings made of about 800 species from the Parkinson drawings.  The artist hadn’t survived the voyage, but he did produce 900 complete watercolors and as well as hundreds of sketches.  Unfortunately, Solander died in 1782 before the project was completed, and Banks seems to have given up first-hand work on botany after his death.  Instead, Banks became more involved in projects to promote botanical exploration as well as agriculture.  The Banks’ Florilegium wasn’t published until the 1980s in 34 massive volumes.  Solander did not publish much but he was obviously essential to the Endeavour mission, and perhaps even more importantly, to making the Sloane Herbarium a continuingly useful botanical resource.

References

O’Brian, P. (1993). Joseph Banks: A Life. Boston, MA: Godine.

Rose, E. D. (2018). Specimens, slips and systems: Daniel Solander and the classification of nature at the world’s first public museum, 1753–1768. The British Journal for the History of Science, 5 (2), 1–33.

The Linnaean Apostles: Peter Forsskål

2 Forskohlea sp Linn

Forskohlea sp. (LINN 605.1) from the herbarium of the Linnean Society, London

I should note before introducing the second of the students of Carl Linnaeus whom he sent out to gather exotic plants for him, that I am only going to deal with four of them in this series of posts, though there were about 20 by one count and 17 are listed in a booklet available online, The Apostles.  I chose these men because they are the ones I’ve most often encountered in my reading about botanical explorations, and they seemed particularly intriguing, as in the case of this post’s subject, Peter Forsskål (1732-1763).  Like several others in the group, he died on his travels and had interests that stretched well beyond botany.  Born in Finland, he spent much of his childhood near Uppsala and then attended the university there, studying with Linnaeus.  However, his chief interest was in orientalism.  He showed such promise that he was sent to Germany to study with Johann Michaelis, a leading biblical scholar and specialist in Near Eastern languages.  Forsskål again excelled, and his intellectual thirst was so great he continued to study botany as well as entomology and philosophy (Baack, 2013).

There was a liberal political environment at the university that excited Forsskål and inspired him to write a pamphlet called Thoughts on Civil Liberty.  In 1759, he had it published in Swedish and Latin, though only after the Swedish government censors had made some changes to the text.  This essay contributed to a Swedish freedom of the press act in 1766 (Goldberg, 2013).  However, it did not endear Forsskål to the faculty in Uppsala who refused to offer him a faculty position.  Meanwhile, Johann Michaelis urged the Danish king to finance a scholar fluent in Arabic to go to Yemen to study the natural sciences and geography of the Near East.  Scholars from Britain and the Netherlands were investigating this field, and Michaelis wanted to have a direct line to the area.  The King’s advisers were interested in encouraging Danish culture and science, so they even provided extra funds—two years of support for preparations.

Forsskål spent his time studying with Linnaeus on how to describe plants accurately and take notes on geography and climate.  He also continued studying Arabic and biblical history, though as the expedition continued it became more about natural history and less about religious studies.  There were five in the scientific contingent besides Forsskål:  a philologist to study language and custom, a physician, an artist, an assistant, and finally a cartographer and mathematician, Carsten Niebuhr, who was the only one of the six to return alive from the expedition that lasted over six years.  They sailed from Copenhagen in January 1761 and reached Alexandria in September.  Several difficulties kept them in Egypt for almost a year.  Forsskål used his time well once he worked out how to function effectively in the area.  He was attacked and robbed twice while exploring in the desert, so he hired a Bedouin guide who led him to interesting local specimens.  He also grew a beard, took an Arabic name, and dressed in robes.  Eventually he collected 576 species in Egypt; half were new species.  This was the most extensive Egyptian plant collection made in the 18th century.  He also wrote on the fertility of Egyptian soil and the relationship between geography and plant characteristics.  Though I am focusing on plants here (of course), Forsskål also collected insects and shells, sending everything back to Linnaeus.

From Egypt, the group then set out for Yemen, sailing across the Red Sea where Forsskål made extensive observations on marine biology.  In Yemen, he and Niebuhr often explored together, taking multi-day excursions into its biologically and geologically varied regions:  coastal plain and marshes, desert, and highlands.  Local officials and inhabitants were helpful.  In six months he managed to collect 693 different plant species, more than half new to science.  He also took extensive notes on plant habitats and distributions.  It’s obvious that Niebuhr as a cartographer would have had input here, and it’s easy to envision their conversations as they traveled.  Unfortunately, Forsskål only managed to complete six months of collections in Yemen before he died there of malaria in July 1763.  Niebuhr, surviving Yemen, went on with the expedition to India.  He eventually returned to Denmark in 1768 and arranged for the publications of Forsskål’s Flora Aegyptiaco-Arabica in 1775, even using his own funds to see the project through to completion.

Needless to say, Linnaeus made good use of the materials Forsskål sent him; these were particularly important because they included the Arabic names for the plants.  Paired with the specimens, these provide information that is still valuable on what was growing in the area.  Forsskål did collect duplicates, but the bulk of his collection, over 1300 sheets, is held in the herbarium of the Natural History Museum in Copenhagen where it is considered the institution’s greatest treasure.  Forsskål was only 31 when he died, but he made a significant contribution to science and also to human rights with his essay on civil liberty.

References

Baack, L. J. (2013). A naturalist of the Northern Enlightenment: Peter Forsskål after 250 years. Archives of Natural History, 40(1), 1–19.

Goldberg, D. (2013). Peter Forsskal: Goettingen prodigy and author of one of the least known jewels of Enlightenment literature. Goettingen Academy of Sciences.

The Linnaean Apostles: Pehr Kalm

1 Kalmia angustifolia 560.2

Kalmia angustifolia (LINN 560.2) from the herbarium of the Linnean Society, London

In the last series of posts (1,2,3,4), I discussed Carl Linnaeus’s time in the Netherlands where he was able to broaden his knowledge of plants and solidify his ideas on taxonomy.  When he returned to Sweden, he stayed put for the rest of his life, never leaving his native land again.  However while in Holland, England, and France, his exposure to plant collections from all over the world—living and preserved—made him realize that what was available in Sweden was indeed limited.  He tackled this problem in two ways.  First by maintaining a large correspondence with a broad range of botanists and collectors throughout the world, and secondly helping to engineer collecting trips by some of his students and proteges.  He himself called them “apostles,” but in most cases they were less involved in proselytizing his taxonomic system and more committed to collecting new species to augment his massive work, Species Plantarum, his attempt to name and describe all known plants.

One of the first travelers for Linnaeus was Pehr Kalm (1716-1779), who studied at the University of Uppsala in the early days of Linnaeus’s professorship there.  They were both interested in useful plants that would strengthen Swedish agriculture, and Kalm studied economics with an eye toward this issue.  Canada seemed a particularly attractive area in which to search for new species, because it was at a similar latitude to Sweden.  In addition, Linnaeus was interested in obtaining more plants and information from two men in the British colonies, with whom he had already been in communication, John Bartram and Cadwallader Colden.  He and other professors managed to finance Kalm’s trip.  While spending several months in London waiting for transport, he visited Peter Collinson, a merchant and botanical enthusiast who had met Linnaeus several years earlier during the latter’s London visit (Blunt, 1971).  Kalm also went to the farm of another gentleman botanist, William Ellis, author of The Practical Farmer (1732). They discussed how weeds such as bracken could be useful within the economics of farming.  No trip to London for a botanist would be complete without a visit to Chelsea Physic Garden, and in his journals Kalm also noted plants in the fields and meadows he encountered on his walks.

Kalm finally reached Philadelphia in September 1748 with a letter of introduction from Linnaeus to Benjamin Franklin, who in turn connected him with John Bartram, a Philadelphia farmer and nurseryman.  Bartram had been sending seeds, specimens, and plants for several years to Peter Collinson from whom Linnaeus had received some Bartram material.  But of course Linnaeus wanted more, and Kalm was able to dispatch specimens and seeds.  He stayed with Bartram for a couple of days, examining his living collection and herbarium, and remained in the Philadelphia area until the following spring.  Most of his time was spent in and around a Swedish colony in Racoon, New Jersey.  The Swedish government had established it in the 1630s, and though it was taken over by the British after 20 years, residents in the area maintained Swedish traditions, yet today the town no longer exists.

In spring 1749, Kalm explored further north, visiting Cadwallader Colden in his home north of New York City.  Colden was interested in botany, had corresponded with Linnaeus, and welcomed Kalm’s visit.  While there, Kalm also met Colden’s daughter Jane, another plant enthusiast.  Robbins (1969) speculates that it might have been Kalm who encouraged her to begin work on her flora of the region, which she eventually produced with 300 of her own drawings.  From there, Kalm ventured farther north eventually reaching Montreal and then went on to Quebec.  In November he returned to Philadelphia by way of Albany and Saratoga.  On this trip he gathered watermelon, walnut, pumpkin, cotton, and early-ripening maize seeds which could possibly grow in Sweden (Juel & Harshberger, 1929).  Because he was thinking in terms of agriculture he was also interested in meteorology, kept weather records on his trip, and asked Bartram to also take readings in Philadelphia.

During the winter of 1749-50, Kalm married Anna Sadin, a Philadelphia widow.  In the spring he set out again traveling through western Pennsylvania and north to Niagara Falls, providing the first detailed account of the area and visiting the Iroquois who lived there.  This meant more specimen and seed collecting, and he packed up his materials back in Philadelphia in fall 1750.  He and his wife sailed to England in February, 1751 and arrived in Sweden in May.  He quickly distributed seeds for cultivation, and of course, visited Linnaeus who was thrilled with Kalm’s specimens.  In his 1753 Species Plantarum, Linnaeus describes 700 North American species, including 60 new ones that were collected by Kalm.  These included a species of Kalmia, a beautiful Ericaceae that its namesake had found in New Jersey. 

Kalm appeared to have made three collections of North American plants, one for Linnaeus which is now part of the collection at the Linnean Society, London, one for himself that was destroyed in a fire, and one given to Queen Lovisa Ulrika of Sweden for her support of his travels.  The latter specimens are now in the herbarium of the Museum of Evolution at the University of Uppsala (Lundqvist & Moberg, 1993).  Kalm spent the rest of his life teaching in Åbo, Finland.  In 1752 he published a journal of his travels which was translated into English, and also wrote several articles on agriculture for the Swedish Academy.  Unfortunately, none of the plants he grew from North American seeds were ever used in Swedish farming, and even the mulberry trees he tended as the first step in developing a Swedish silk industry eventually died.  His most lasting fame is in Kalmia and that is wonderful in itself.

References

Blunt, W. (1971). The Compleat Naturalist: A Life of Linnaeus. New York, NY: Viking.

Juel, H. O., & Harshberger, J. W. (1929). New light on the collection of North American plants made by Peter Kalm. Proceedings of the Academy of Natural Sciences of Philadelphia, 81, 297-303.

Lundqvist, S., & Moberg, R. (1993). The Pehr Kalm Herbarium in UPS, a Collection of North American Plants. Uppsala, Sweden: Uppsala University.

Robbins, P. I. (2009). Jane Colden: America’s First Woman Botanist. Fleischmanns, NY: Purple Mountain Press.

Linnaeus Beyond the Netherlands

4 Chelsea Garden

Chelsea Botanical Garden, London

This is the last of a series of posts about Carl Linnaeus’s three-year stay in the Netherlands and how it shaped his future career.  While there he had two opportunities to travel to other parts of Europe and meet leading botanists of the day.  It was while living on the estate of George Clifford at Hartekamp and working on cataloging his collection (see last post), that Linnaeus took time off for a month in England to look into what he had heard to be a vibrant botanical community there.  Clifford agreed to this hiatus and even financed it, with the stipulation that Linnaeus return with new plants for his estate.

Not surprisingly, Linnaeus first visited Hans Sloane, then an aged icon among collectors, who opened his herbarium to the Swede.  Jan Frederik Gronovius had already sent Sloane a copy of Linnaeus’s Systema Naturae, and Herman Boerhaave wrote a letter of introduction in which he put Linnaeus on a par with Sloane, describing them as “a pair of men whose equal is hardly to be found in all the world” (quoted in Blunt, 1971, p. 110).  Sloane didn’t quite see things that way and didn’t pay that much attention to Linnaeus who later described Sloane’s herbarium as disorganized.  His first meeting with Philip Miller, the head of the Chelsea Physic Garden, was also less than a success, but eventually Miller gave Linnaeus a good selection of plants to take back to Clifford, as well as herbarium specimens that William Houston had collected in Central America.

In London, Linnaeus met another key member of the botanical confederacy, Peter Collinson, who had already begun a long-term correspondence with John Bartram, the Philadelphia naturalist and nurseryman.  Over a 30-year period, Bartram sent a large array of specimens, seeds, and cuttings to Collinson, who in turn distributed them to a number of the leading gardeners of the day who were anxious to have the latest finds from North America.  Collinson got along well with Linnaeus, and they continued to correspond over the years, with Linnaeus examining some Bartram specimens that thus became types for Linnaean species.  Linnaeus must have met up with Georg Ehret in London, since the artist wrote that he had given him plates to finish Clifford’s catalogue.  In addition, John Martyn, a professor of botany at Cambridge and a London physician, was impressed enough with Linnaeus that their meeting led to a regular correspondence.

Linnaeus also managed time for a trip to Oxford where Johann Jacob Dillenius was professor of botany.  As with several other Linnaean first meetings, this one did not go well because Dillenius had read some of Linnaeus’s early publications, and he felt they threw botany into confusion.  After a few frosty meetings, they finally reconciled when Linnaeus showed Dillenius that he was wrong about his description of the genus BlitumThen Dillenius finally appreciated the depth of Linnaeus’s knowledge, and they had a lively conversation and continued to correspond afterwards.  Obviously Linnaeus’s time in England was very fruitful and provided him with several important contacts who would continue writing to him with information for years to come.

When Linnaeus left Hartekamp in fall of 1937 after finishing the catalogue that would become Hortus Cliffortianus, he went back to Leiden and spent the winter there, working with Adriaan van Royen in the botanic garden, classifying plants according to his sexual system (Rutgers, 2008).  In the spring, he started out for his return to Sweden by going in the opposite direction, to Paris, to visit the famous Jardin des Rois where he met the de Jussieu brothers.  Antoine was older, a professor of botany at the Jardin and a physician; he was a busy man.  He had one meeting with Linnaeus and introduced him to Bernard who then served as his guide.  Bernard de Jussieu showed him the herbarium, and they went through Joseph de Pitton Tournefort’s specimens, a broad collection that included plants from his voyages to the Middle East as well as to the Caribbean area.

Linnaeus also worked in the Jardin’s botanical library, where there were many books of which he had been unaware.  He prepared a ‘wish list’ and later procured a number of these titles.  At the Jardin, he met two of the most accomplished botanical artists of the day, the elderly Claude Aubriet, who had worked with Tournefort, and his pupil Françoise Madeleine Basseporte.  Aubriet showed Linnaeus the large collection of paintings of plants in the Jardin done over the years, so again, as with the time he spent with Georg Ehret, Linnaeus developed a taste of what the best botanical art looked like.  Paris allowed him to deepen still further his knowledge of botany in terms of specimens, living plants, books, and art.  All these were to figure in his future work, and he left for Sweden having made the best possible use of his three years away from home.  Those who read the first post in this series might remember that Linnaeus’s journey had in part been urged upon him by his future father-in-law who agreed to his daughter’s engagement only with the proviso that there be a three-year hiatus in their relationship.  Having fulfilled the agreement, Linnaeus was still an ardent suitor, and when he got back to Sweden, plans for the wedding proceeded.

References

Blunt, W. (1971). The Compleat Naturalist: A Life of Linnaeus. New York, NY: Viking.

Rutgers, J. (2008). Linnaeus in the Netherlands. TijdSchrift Voor Skandinavistiek, 29, 103–116.

Linnaeus in the Netherlands: George Clifford

3 Clifford Hypericum androsaemum

Hypericum androsaemum from the Clifford Herbarium, courtesy of the Natural History Museum, London

As I mentioned in the first post in this series, Carl Linnaeus had just begun work with Johannes Burman at the Leiden Botanic Garden when George Clifford (1685-1760) asked Linnaeus to write a catalogue of the plants in his garden at Hartekamp, near Haarlem in the Netherlands.  It took some convincing for Burman to release him, but it ended up well for Linnaeus.  He spent over two years at Hartekamp, where he had available to him a large collection of tropical plants from around the world.  Linnaeus had already sketched out his Systema Naturae (1735) before he left Sweden, but his knowledge of plant diversity was limited to northern Europe.  Then he met Jan Frederik Gronovius, who had studied plants that John Clayton had sent him from Virginia and Burman, who had Paul Herman’s specimen collection from Ceylon (now Sri Lanka).  His horizons were broadening (see last post).

Clifford was a wealthy Dutch financier and a director of the Dutch East India Company (VOC) that oversaw a worldwide shipping organization making the Netherlands a mercantile power.  From the VOC’s creation in 1602, its captains and ship surgeons were given directions on how to make collections and transport specimens, seeds, bulbs, and cuttings back home.  The more exotics that reached home, the more the Dutch became avid gardeners hungry for still more plant novelties.  Because of his position, Clifford had first dibs on the plants that arrived in Holland, and he had the interest and knowledge to appreciate them.  To give a sense of the scope of his collection, he had four greenhouses, one each for plants from Europe, Asia, Africa, and the Americas.  At this time, gardening and sophisticated plant collecting were status symbols for the elite; Clifford’s Hartekamp was obviously a premier example.  Even his herbarium specimens reflected his status.  The sheets had elaborately printed labels, and the cut end of each plant was covered with a printed urn (Thijsee, 2018).  This became a fad at the time among the rich and botanically sophisticated (see figure below).

Among the living plants in Clifford’s unique collection was a banana tree, which was growing well but had never blossomed or produced fruit.  Linnaeus gave it special attention and took credit for inducing it into flower in four months with a regimen of restricting watering, and then watering generously.  This was one of the first times this feat had been achieved in Europe and was so noteworthy that Linnaeus wrote a short book on the plant, and Clifford had it published (Rutgers, 2008).  This added luster to both their names; it also indicated Linnaeus’s skills with living plants as well as with identifying specimens.

Another important event during this time was the arrival of the German artist Georg Ehret at Hartekamp in 1736.  Ehret had already produced a large portfolio of botanical watercolors for several patrons, none of whom paid very well.  He had come to the Netherlands after doing some work in England and called on Clifford in the hope of finding further employment.  Clifford was indeed interested in Ehret’s work and even paid his asking price for a number of paintings.  Ehret remained at Hartekamp for a month, working on illustrations for Clifford’s catalogue.  Linnaeus explained to Ehret his plant classification system based on the reproductive structures in flowers.  He had worked out 24 classes simply by counting the number and arrangement of the stamens or pollen-producing male organs, with the 24th class reserved for those without visible stamens.  Within each class were subclasses depending up on the number of female organs.  The beauty of the system was its relative simplicity, grounded in traits that were usually visible and countable.

Ehret illustrated the system with a chart that has become famous, a simple visual representation of the 24 classes (see figure below).  He published it shortly after leaving Hartekamp and Linnaeus also published it much later, but not crediting Ehret.  Working in close proximity together, even for a month, must have been important to them both during this early formative period in their careers.  Ehret, who had already developed the practice of dissecting flowers and illustrating their parts, often with magnification, learned from Linnaeus the pivotal importance of these structures in identifying species.  On the other hand, Linnaeus was able to see the artistic and intellectual work that went into creating first-rate botanical art.  In their book Objectivity, Lorraine Daston and Peter Galison (2007) write of four-eyed sight, which results from an artist and a scientist working and looking together, resulting in an image that satisfies both.  Linnaeus and Ehret could very well have collaborated in this way.  After he left Hartekamp, Ehret had a long career in England producing illustrations for many major botanical works including those of Philip Miller and Christoph Jacob Trew, who had been an early patron of Ehret’s in Germany.

3 Ehret
Georg Ehret’s diagram of Carl Linnaeus’s classification system, courtesy of the Biodiversity Heritage Library

Most of the illustrations in the Clifford catalogue were done by Ehret and the remainder by Jan Wanderlaar, who also engraved the plates.  It took Linnaeus nine months to write the text (Blunt, 1971).  The species descriptions were organized according the classification system Linnaeus had laid it out in his Genera Plantarum, which was also published during this time (1737).  While he was in Hartekamp, he published early versions of other works as well.  Clifford also afforded him the time and the resources to become better educated in botany.  Besides his herbarium and garden, Clifford also had a substantial library, with all the leading botanical references of the day.  Hartekamp must have been a difficult place to leave.  However, after spending almost three years in the Netherlands, Linnaeus’s thoughts were of Sweden.  Yet he didn’t go directly home.  His further wanderings will be examined in the next post.

References

Blunt, W. (1971). The Compleat Naturalist: A Life of Linnaeus. New York, NY: Viking.

Daston, L., & Galison, P. (2007). Objectivity. New York: Zone.

Rutgers, J. (2008). Linnaeus in the Netherlands. TijdSchrift Voor Skandinavistiek, 29, 103–116.

Thijsse, G. (2018). A contribution to the history of the herbaria of George Clifford III (1685–1760). Archives of Natural History, 45(1), 134–148.

Linnaeus in the Netherlands: Mentors

2 Claytonia virginica

Specimen of Claytonia viriginia collected by John Clayton, courtesy of the Natural History Museum, London.

In the last post, I outlined the early days of Linnaeus’s three years of travel (1735-1738) and mentioned his early meetings with Herman Boerhaave, a physician and retired director of the Leiden botanic garden, and Jan Frederik Gronovius, a botanist with a large herbarium.  Linnaeus was much younger than them, and he learned a great deal from both, especially because they allowed him to study their specimen collections.  So they deserve more attention in this series of posts on Linnaeus’s travel experiences (Blunt, 1971).

For many years, Herman Boerhaave taught medicine at the University of Leiden and elevated the institution’s stature.  He then headed the university’s botanical garden and worked to increase its holdings of exotic plants.  He was aided in this by his contacts with the Dutch East India Company ( VOC), one of the leaders at the time in trading with Asia.  Following company instructions, surgeons and captains on VOC ships brought back cuttings, seeds, and specimens of plants they encountered on their travels.  Boerhaave was able to add many of these to his garden and herbarium, four volumes of which are now in the Sloane Herbarium at the Natural History Museum, London.  In addition, he published descriptions of new species and built on the work of botanists such as John Ray and Joseph de Pitton Tournefort in attempting to develop a natural classification system (Rutgers, 2008).  It is no wonder that with this background Boerhaave appreciated what Linnaeus was attempting to do with his Systema Naturae, which he had already sketched out by the time he went to Leiden.

Jan Gronovius was a student of Boerhaave’s.  He was an avid specimen collector and kept up a wide correspondence with naturalists in Europe and beyond.  It was through this network that he obtained John Clayton’s specimens from Virginia (see figure above).  Clayton became interested in botany and plant collecting after meeting Mark Catesby on his second trip to the American Southeast collecting for what became the impressive The Natural History of Carolina, Florida, and the Bahama IslandsAfter Catesby returned to England, Clayton shipped him specimens, which Catesby then passed on to Gronovius.  Eventually Clayton sent specimens and letters directly to Gronovius.

At this time, “sending a letter” across the Atlantic could mean waiting months to a year or more for a response, if indeed a response ever came.  Also at that time there was great interest in North American plants and not only because of their novelty.  Since the climate there was temperate as was that of Europe, species were more likely to acclimatize well and could be introduced into gardens.  Wealthy landowners were clamoring for the latest novelties, and botanists wanted to be the first to describe new species.  This helps to explain why Gronovius published a book, Flora Virginica, based on Clayton’s manuscript and specimens without letting him know about it ahead of time and gaining his permission.  This sounds rather dubious, but he did credit Clayton with finding the plants and sending him information on them along with the specimens.  Also, later observers have noted that because Gronovius was so well connected, his publication likely made Clayton’s work more broadly known than if Clayton himself had written on them.  As a case in point, Gronovius allowed Linnaeus to study the Clayton specimens, and so they became type specimens for a number of the North American plants Linnaeus described in Species Plantarum.  Linnaeus spent the winter of 1737-1738 with Gronovius right before returning to Sweden.  They worked on Clayton’s 1737 shipment of plants, to which they gave Linnaean names, a very early use of his system.

Gronovius was also in touch with another American botanist, John Bartram in Philadelphia.  They were originally connected by Bartram’s patron in England, Peter Collinson, another adept networker.  Bartram sent material to Gronovius, who again allowed Linnaeus to examine it.  This was later than with the Clayton material; Linnaeus by then had his long-term academic position in Uppsala and the two sent packages of specimens back and forth between them.  Eventually Gronovius and Bartram corresponded directly, as did Gronovius and Cadwallader Colden, a New York naturalist whose daughter Jane Colden was also involved in botany and produced an illustrated manuscript on New World plants (Colden, 1963).

One last name that should be mentioned as a Linnaean mentor is someone of his own age whom he had worked with while studying at the university in Uppsala.  There they planned to develop a system to organize all living things.  They divided up different groups between them.  For example, Linnaeus opted for most of the plants, and Peter Artedi selected fish and the Brassicaceae as among his favorites.  Finishing their studies, they went their separate ways, then met by chance in Amsterdam and took up where they left off.  Unfortunately, Artedi soon drowned in one of the city’s canals.  Linnaeus saw to the publication of Artedi’s manuscript on fish, and the approaches they developed to classification greatly influenced Linnaeus’s future work.  This is one of those cases where it’s interesting to speculate on what they would have achieved if they had been able to work together for years.

While the three individuals discussed here were important to Linnaeus’s career, it could be argued that the most important individual of his Netherlands sojourn was George Clifford with whom Linnaeus lived and worked for over two years.  Clifford will be the subject of the next post.

References

Blunt, W. (1971). The Compleat Naturalist: A Life of Linnaeus. New York, NY: Viking.

Colden, J., Rickett, H. W., & Hall, E. C. (1963). Botanic Manuscript of Jane Colden, 1724-1766. New York: Garden Club of Orange and Dutchess Counties.

Rutgers, J. (2008). Linnaeus in the Netherlands. TijdSchrift Voor Skandinavistiek, 29, 103–116.

Linnaeus in the Netherlands

 

1 Systema Naturae

Title page of Carl Linnaeus’s Systema Naturae (1735), courtesy of the Biodiversity Heritage Library.

There is a great deal of talk about the European Union these days, and the advantages of open travel among nations.  Freedom of movement is a wonderful concept in any age, and it’s one experienced by Carl Linnaeus (1707-1778) when he was in his late 20s.  Having completed his education in Uppsala, Sweden and having become engaged to a woman whom he very much desired, he set out for three years of study and travel.  This wasn’t entirely his own idea.  His future father-in-law was not thrilled with his daughter’s beloved, a physician with few financial resources, so he would only bless the match by having Carl agree to a three-year hiatus.  Linnaeus might not have been a man of means, but he was a man who had already learned a great deal about botany and had developed original ideas about how plant diversity should be organized.  He also had some experience of travel having spent a few months exploring Lapland, the northern reaches of Scandinavia.  So in 1735 he took his manuscripts, packed his bags, and headed to the Netherlands, traveling through Germany on the way.  His experiences in Holland and elsewhere in Europe did a great deal to form his ideas and shape his career.  This series of posts will look at some of those influences (Blunt, 1971).

It seems that Linnaeus did not make a good first impression on many people.  There are a number of stories about men who were put off by his self-possessed manner, and then, as they realized what a good mind lurked behind the bravado, became good friends with him.  This was the case with Johannes Burman, a professor of botany and director of the Amsterdam botanic garden.  Burman, who was the same age as Linnaeus, had been at the garden for several years working on the Flora of Ceylon, using primarily the herbarium of Paul Hermann, who had collected there in the 1670s.  After this brief meeting where Burman was unimpressed by Linnaeus, it would probably have been difficult for either of them to predict that they would be lifelong friends.  At this time Linnaeus also visited Albertus Seba who had amassed a large cabinet of curiosities including materials he collected on trips to the East and West Indies.  During these years the Netherlands was an important naval power with far-flung mercantile interests, so along with trade goods—like spices and silks, exotic plants, animals, and artifacts also poured into Dutch ports.  Even though Seba had sold his original massive collection, he was able to build another and showed some of it to Linnaeus on two visits to his home.  He later asked Linnaeus to assist him in preparing a book he was writing on his holdings, but by then the Swede had made other connections (Rutgers, 2008).

Linnaeus next spent two weeks in Harderwijk, the site of a university where for a week’s residency he qualified as a doctor, submitting a thesis he had written in Sweden.  Then he went to Leiden and showed his manuscript of Systema Naturae to the Dutch botanist Jan Frederik Gronovius, who was so impressed with the work that he arranged for its immediate publication as a thin volume of 14 pages that set out the rudiments of Linnaeus’s taxonomic system.  Gronovius also gave him a letter of introduction to Herman Boerhaave, who had retired as head of the Leiden Botanic Garden.  As with Burman, their relation did not begin smoothly, but eventually Boerhaave appreciated Linnaeus’s intelligence and energy.  However, none of these meetings landed him a position where he could earn enough money to allow him to remain in the Netherlands.  He told them that he would have to return home.  That’s when Boerhaave offered to fund a trip to Cape Town, South Africa which was then under Dutch control and was proving to be a botanically rich area.  Linnaeus, however, after his Lapland expedition, did not much relish a long journey with many probable hardships; Sweden was a safer and easier option.

There are more twists to this story.  On his way home, Linnaeus stopped in Amsterdam and again visited Burman, this time with a letter of introduction from Boerhaave.  Burman paid more attention to his visitor, especially after Linnaeus was able to identify a rare plant Burman showed him.  The latter offered to pay Linnaeus for helping to prepare the Flora of Ceylon, and also convinced him that he should definitely call on George Clifford, a wealthy merchant and horticulturalist who lived near Haarlem.  Clifford and Linnaeus got on well because Linnaeus identified many of his hosts’ Indian plants and was sorely tempted by Clifford’s offer to live and work on his estate, with access to his garden and herbarium.  But Linnaeus was committed to Burman.  In the end, Burman and Linnaeus visited Clifford, and Burman agreed to free Linnaeus if Clifford would give him a very desirable book displayed in his library: the second volume of Hans Sloane’s Natural History of Jamaica.  Clifford and Linnaeus were both very fortunate, with the gardener/financier getting an expert to bring order to his collection of specimens, properly name his plants—those in the herbarium and those in the garden—and help in producing a catalogue to make public his botanical treasures.  Linnaeus, on the other hand, was freed of economic worries, had a very comfortable place to live, and great resources to work with, including a first-class library.  What happens then will be the subject of a later post.

References

Blunt, W. (1971). The Compleat Naturalist: A Life of Linnaeus. New York, NY: Viking.

Rutgers, J. (2008). Linnaeus in the Netherlands. TijdSchrift Voor Skandinavistiek, 29, 103–116.

Natural History in 17th-Century Britain: Nehemiah Grew

4 Grew plum

Transverse section through plum branch, from The Anatomy of Plants, Biodiversity Heritage Library

When I think of Nehemiah Grew (1641-1712), an image of a cross section through a stem appears in my mind’s eye (see above).  I remember Grew as the creator of magnified images of plant tissue that have a rather inorganic feel to them in their rigid rows of cells.  He was doing microscopic studies at about the same time as Robert Hooke, whose illustrations of plant cells are less regular, and somehow have a more organic feel.  They were both attempting to communicate the new world they were exploring and trying to make sense of it.  In an article to commemorate the tercentenary of Grew’s birth, the plant morphologist Agnes Arber (1941) noted that Grew held a mechanistic view of the universe and saw the microscope as a way to clear up mysteries of life by observing its constituents.  Because of this viewpoint he also developed mathematical descriptions and was concerned with how to communicate the scale of objects seen under the microscope.  This is a reminder that at the time there were no adequate standards of measurement for the microscopic world.  So Grew used comparison to give his reader some idea of the size of what he was seeing, for example, that something was one-fifth the size of the cheese mite or the width of a marsh mallow seed.

Another major contributor to the beginnings of plant anatomy was the Italian Marcello Malpighi who like Grew was a physician, though Grew practiced medicine while Malpighi taught in a medical school and also did a great deal of research on animal anatomy.  In fact, he began studying plants because he found animal tissue so complex and wanted to see if the “simpler” structures of plants could give him clues.  Grew and Malpighi are usually mentioned together because in some ways, their work is similar.  They labored independently without any knowledge of the other’s research until Grew produced a paper for the Royal Society of London (RS) shortly before Malpighi sent a manuscript read at an RS meeting.  After that they followed and cited each other work.

The consensus is that they achieved similar results.  Alan Morton  (1981) claims that Malpighi saw more clearly than Grew in some details, but Grew’s culminating The Anatomy of Plants is the fuller and clearer work, with a more integrated view of plant structure.  Agnes Arber (1942) also wrote a comparison of their contributions and contends that Grew may be better known because he wrote in English, while Malpighi published in Latin.  Arber notes:  “His Latin, though lively, is not very correct, and its interpretation is often by no means easy” (p. 15).  But she considers Malpighi’s illustrations, made from his drawings, as excellent.  Some of Grew’s illustrations are noteworthy because, while Malpighi made attempts at depicting microscopic structures in three dimensions, Grew did it more successfully.

Since this set of posts is on British botanists, I’ll end by noting some of Grew’s most important findings, though in many cases, Malpighi also produced similar results.  Grew described the main anatomical differences between roots and stem.  This required a great deal of work examining a variety of different species.  The same was true of deciphering the vascular network in these structures.  Grew admits that he got the idea for the spiral form of vessels from Malpighi, but he came up with the name “parenchyma” for the material packed around the vessels.  While he depicted a great deal of order in plant tissue as orderly, he did not really conceive of cells as the basic unit of plant structure, though Robert Hooke had already coined the term for the structures he saw in cork cambium.  Grew was able to differentiate between the scattered vascular bundles in monocots and the more ordered structures in dicots; he identified the medullary rays in dicot stems as well.  Grew compared the cell walls to woven fibers and more generally compared a plant’s inner structure to a textile fabric.  Arber (1913) quotes a long passage where he describes plant tissue as fine lace with an intricate and delicate texture.  At one point he writes:  “One who walks with the meanest Stick, holds a Piece of Nature’s Handicraft, which far surpasses the most elaborate Needle-Work in the World” (p. 54).

Grew also went into detail on the structure of flowers.  Though he accepted the idea of sexual reproduction in plants, he wasn’t able to work out the process.  He presented much information on seed structure in a variety of species and carefully observed seed development, coining the term radicle for the embryonic root.  He also did simple experiments on the movement of sap, but his major work was anatomical.  For a century and a half after Grew and Malpighi there was little further development in the field.  It may be that it had to wait for the creation of better microscopes, or for further work in plant physiology.  Or perhaps some of the lack of interest in the field may have been due to those images that so intrigue me.  They presented such a well-developed, finished view of plant structure, that others might have considered the job of working out plant architecture to be complete.  After all, plants were simpler than animals, how much more was there to know?

References

Arber, A. (1913). Nehemiah Grew (1641-1712). In F. W. Oliver (Ed.), Makers of British Botany (pp. 42–64). Cambridge, UK: Cambridge University Press.

Arber, A. (1941). Tercentenary of Nehemiah Grew (1641-1712). Nature, 147(3734), 630–632.

Arber, A. (1942). Nehemiah Grew (1641-1712) and Marcello Malpighi (1628-1694): An essay in comparison. Isis, 34, 7–16.

Morton, A. G. (1981). History of Botanical Science. New York, NY: Academic Press.