‘The Roots of Healing’: The books that fed our knowledge of medicinal plants

The German polymath Hildegard von Bingen, a Benedictine abbess in the High Middle Ages, developed a holistic view of healing while working in her monastery’s herb garden and caring for the sick in its infirmary. 

She likened a physician treating patients to a gardener tending to plants. Between 1151 and 1158, von Bingen put this perspective to parchment, composing “Physica,” a medical treatise that documents the medicinal properties of 230 plants. Many of the herbal remedies she describes — ginger to treat stomachaches and aloe to soothe rashes — are still used today.

A 1533 printed copy of “Physica” is displayed in “The Roots of Healing: Six Centuries of Medical Herbals,” an exhibit on view in the Hanke Exhibition Gallery in Sterling Memorial Library through March 22 that explores the history, content, and influence of herbals — written guides that describe plants and their medicinal properties.

Drawn from the Yale Library’s collections, particularly those at the Beinecke Rare Book and Manuscript Library and the Harvey Cushing/John Hay Whitney Medical Library, the objects on view include early 15th-cenutry herbals that pre-date Gutenberg’s printing press to modern-day examples. 

“Herbal-derived medicines still have a prominent place in our hospitals and medicine cabinets,” said Dr. Matthew Morrison, an emergency physician and lecturer in the Medical Humanities at Yale College, who curated the exhibition. “The herbals on display intertwine art, botany, human physiology, and spirituality. They demonstrate the idea that there is no science without a human touch, without a human eye.”

Abbess von Bingen, Morrison said, embodies the intersection of science and the humanities at the exhibit’s heart. “She was an artist-scientist par excellence, which captures the spirit of what we’re trying to convey,” he said.

Here are five more things to know about “The Roots of Healing”:

1. The exhibit covers the history of bookmaking, particularly the transition from manuscripts to printed books.

A manuscript on display is opened to pages bearing several crude but lively illustrations, including a depiction of two boars munching on what looks to be a wild carrot. The book, which dates to circa 1400, draws from various ancient and late-antique texts, including “De materia medica,” a five-volume pharmacopeia written between 50 and 70 C.E. by Pedanius Dioscorides, a Greek physician.

Herbals, like other books, became much more widely available in the mid-15th century with Johannes Gutenberg’s invention of the moveable-type printing press. At the same time, Morrison said, the authors of Renaissance-era herbals began to prize data and evidence over the theories that drove classical texts. 

Herbals also became more aesthetically pleasing as printmaking advanced, allowing the creation of lifelike illustrations. 

The first generation of printed herbals, represented in the exhibit by copies of the “Buch der Natur,” from 1499, or “Hortus Sanitatis,” from 1491, contain woodblock-printed illustrations that are austere, in silhouette, and feature rudimentary coloring. “It’s certainly elegant in its way,” Morrison said, “but if you have to rely on this image to identify a plant you might be ingesting, God help you.” 

By the 16th century, the illustrations become more elegant and precise, as in works like the live-drawn “Historia Stirpium” by German physician and botanist Leonhart Fuchs. A copy in the Yale exhibition is opened to illustrator Albrecht Meyer’s lovely depictions of a chrysanthemum on one page and an eranthemum on the other. “The draftsmanship by Albrecht Mayer is exquisite, and it is, in my opinion, among the most sumptuous herbals ever created,” said Morrison.

2. An 18th-century herbal on view represents a genuine labor of love.

Elizabeth Blackwell’s “A Curious Herbal,” published between 1737 and 1739, is the product of her tireless efforts to free her husband, Alexander, from debtors’ prison. A trained artist and amateur botanist, Blackwell poured herself into creating an herbal that depicted and documented medicinal plants. She provided Alexander, who had medical training, with her botanical illustrations, and he would add the plants’ scientific names and properties from his prison cell. 

Their book documented 500 plants and proved popular on the strength of Elizabeth’s illustrations. Indeed, the project raised sufficient funds to get Alexander released. But, alas, a happy ending eluded the Blackwells: A genuine rogue, Alexander soon again fell into debt, fled to Sweden, and was beheaded for conspiracy against that country’s king in 1747.

3. Several medicinal plants represented in the exhibit are still used today.

In “The American flora, or History of plants and wildflowers,” an 1847 herbal, visitors will see an illustration of an aloe plant. A recent study found that gel produced from aloe leaves reduces the healing time of second-degree burns by four days, according to the exhibit label.

They’ll also learn about quinine, which is derived from the bark of the Peruvian cinchona tree and remains a powerful treatment against malaria. During the 17th century, Spanish Jesuit missionaries in South America noticed Indigenous peoples using the tree’s bark to treat fevers. They exported the cure to Europe, where apothecaries dubbed it “Jesuit’s bark.” 

Purple anise, depicted in an 1817-1820 copy of volume three of “American medical botany” on view, is a close relative of star anise, the source of shikimic acid — a vital precursor in the synthesis of Tamiflu, the popular flu medicine. 

4. One of the works on view is a canonical work of Japanese botanical culture.

“Honzō zufu” is an encyclopedic tome of 2,920 plant descriptions accompanied by sumptuous woodblock prints. Compiled by Kan’en Iwasaki, a naturalist and samurai in the Tokugawa Shogunate, the work was published in 95 volumes from 1830 to 1844. 

“The ‘Honzō zufu’ began as an herbal but evolved into a semi-compendium of the plants of Japan,” said Morrison. “It was Iwasaki’s life’s work, and only compiled and published by his family after his death. It’s truly one of the crowning achievements of Japanese herbal art.”

5. The exhibition documents a remarkable modern success story in herbal medicine. 

In 1972, Chinese biochemist Tu Youyou discovered artemisinin, a potent anti-malarial compound, through extensive research in ancient Chinese herbals. The compound was first referenced as a remedy for quartan malaria in Ge Hong’s “Handbook of Prescriptions for Emergencies,” which dates to between 317 and 420 C.E. 

Artemisinin is a crucial malaria therapy, credited with saving millions of lives. Youyou was awarded the 2015 Nobel Prize in Medicine for her discovery. In her Nobel lecture, the biochemist stressed the value of integrating traditional herbal medicine with modern scientific methods. 

“From our research experience in discovering artemisinin, we learned the strengths of both Chinese and Western medicine,” she said. “There is great potential for future advances if these strengths can be fully integrated.”

Morrison noted that only about 5% of 250,000 known species of flowering plants have been studied for medicinal uses. The discovery of a single molecule with medicinal properties, he added, can potentially yield dozens of treatments.

“We live in an exciting time for herbal medicine, given the technology that has become available,” he said. “There is a universe out there remaining to be discovered.”