The Natural History of Pliny, Volume 5 (of 6)

In Short

This volume forms a dense, encyclopedic survey of ancient Roman medicine, botany, and natural phenomena, detailing the therapeutic properties of forest trees, cultivated plants, domestic and wild animals, human secretions, and mineral substances. Moving systematically across natural domains, the text outlines hundreds of empirical remedies, folkloric treatments, and historical anecdotes that define classical medical thought. It details how bark, leaves, animal blood, gall, and specialized salts were deployed to heal wounds, neutralize poisons, drive away pests, and treat chronic ailments. Beyond simple lists of recipes, the work charts the historical development of medical arts from divine origins through Greek physicians like Hippocrates to Roman practice. It has endured because it serves as an irreplaceable window into the intellectual landscape of classical antiquity, capturing a moment when empirical observation, religious superstition, and philosophical speculation were inextricably intertwined. Through its relentless cataloging of the natural world, the text reveals how ancient civilizations sought to understand physical reality, master human vulnerability, and harness the hidden sympathies and antipathies governing all living things.

The Story

The exposition opens by establishing that the natural world is governed by active sympathies and antipathies, setting the theoretical framework for understanding how physical substances interact with the human body. The survey begins in the forest, analyzing remedies derived from trees and woody plants. Sacred mistletoe gathered from the robur oak without iron tools acts as an emollient salve for sores, while the bark of the cork tree stops hemorrhage from the mouth and nose when taken in warm water, and beech leaves chewed by hand soothe painful gums. Boiled alder leaves resolve stubborn tumors, and pitch trees yield rich resins that heal wounds. Ivy varieties possess complex cooling properties that calm severe headaches when pounded with rose oil and vinegar, though excessive doses disturb the mental faculties. The investigation expands to marsh and crop plants like aron and dracunculus, which possess the remarkable ability to stupefy poisonous serpents and protect stored food.

From arboreal remedies, the inquiry shifts to wild herbaceous plants, simultaneously offering a trenchant critique of how medical knowledge has been preserved and lost. The historical narrative laments that vast numbers of beneficial herbs remain unnamed and untested because traditional wisdom was veiled in the Greek language, ignored by careless urban physicians, or kept secret by greedy practitioners who refused to share their findings. Discoveries often relied on sheer chance or royal patrons, such as King Juba of Mauritania, who named the fleshy euphorbia plant after his personal physician Euphorbus. Botanical cataloging continues through marsh plants like nymphæa, spear-shaped lonchitis, and coastal crethmos—a wild succulent eaten by rural peasants and celebrated for clearing internal obstructions. Every root, stem, and seed is mapped to specific physiological disorders, from fractured bones to persistent fevers.

The argument then advances from the botanical realm into remedies derived from living creatures, starting with human beings and foreign beasts. Human biology itself is shown to possess innate magical and antipathetic forces. Certain lineages, such as the Psylli and Ophiogenes, possess bodies that naturally repel serpents, while the islanders of Tentyris terrify crocodiles merely with the sound of their voices. Extraordinary rituals and folk traditions are recorded alongside physical therapies: Roman consuls like Mucianus carried live flies in white linen to ward off ophthalmia, and citizens affixed nail parings to doors to transfer fevers. Political figures exploited these natural properties for personal ends, as when the populist tribune Drusus drank goat's blood to create a sickly pallor, convincing the public that his political adversary Quintus Cæpio had poisoned him. The text then evaluates foreign megafauna, noting that elephant blood alleviates consumption, the touch of an elephant’s trunk cures headaches, and lion gall acts as a potent dispersive agent. Bull’s gall carries such intense power that it can impart a golden luster to copper surfaces, whereas horse gall is classified as a lethal poison.

As the scope narrows to domestic animals and specific internal maladies, the text details how physical contact transfers disease from humans to beasts. Placing a sucking whelp or a small Melitæi dog against a patient's abdomen draws out intestinal agony, often killing the animal while restoring the human. Diets of roasted African snails, kid's rennet, and deer horn ashes are systematically prescribed for dysentery, tapeworms, and bladder stones.

This leads directly into an overarching history of the medical profession itself. The narrative traces medicine from its divine roots with Aesculapius through the Trojan War, when practitioners focused exclusively on treating battlefield wounds. A major shift occurred during the Peloponnesian War when Hippocrates of Cos copied out patient records from the temple of Aesculapius—allegedly burning the building down afterward—to establish the clinical branch of medicine. Disciples like Prodicus created lucrative subfields like iatraliptics, while Erasistratus earned immense wealth, including one hundred talents for curing King Antiochus. Subsequent medical theorists like Chrysippus refined these doctrines with elaborate rhetorical arguments, transforming medical practice into an immensely profitable industry across the Greek and Roman worlds. The Sicilian physician Acron founded the Empirics, grounding practice in experimental observation rather than theoretical speculation.

Despite this professionalization, unusual animal cures continued to proliferate. House weasels and bedbugs are analyzed as surprisingly potent counter-poisons; bedbugs eaten by poultry render the birds completely immune to fatal asp strikes. Birds also supply crucial preparations, such as male pigeon blood for bloodshot eyes and swallow ashes for improving vision.

Finally, the text culminates in an examination of inorganic earth phenomena, specifically deadly waters and natural salts. It surveys dangerous springs across the ancient Mediterranean, including Armenian waters containing fatal black fish, the petrifying stream of Nonacris, Mount Soracte's boiling sunrise spring, and the corrosive waters of Tempe. The entire volume concludes with an exhaustive survey of sea, lake, and fossil salts. From the deep red salt of Memphis and the purple salt of Centuripa to the luminous, mirror-like salt of Gela and the fragrant saffron salt of Cappadocia, salt is presented as nature's ultimate seasoning, preservative, and medicinal gift, bringing the vast catalog of natural wonders to a structured close.

How It Unfolds

• The woods yield secret cures

The survey opens among forest trees and climbing vines, detailing how raw bark, leaves, and sap cure human bodily injuries. Oak mistletoe harvested without iron calms inflamed swellings, while cork tree bark and cypress leaves arrest internal hemorrhage. Even noxious plants like ivy yield cooling topical salves for severe headaches when mixed with rose oil and vinegar.

• Ignorance and secrecy obscure botanical knowledge

The text turns to wild plants while condemning the historical decline of botanical research. Many beneficial simple remedies remain completely unknown because ancient texts remained veiled in Greek or uneducated rural gatherers failed to record their discoveries. Furthermore, secretive medical practitioners deliberately hid effective herbs to protect their own professional profits.

• Wild herbs reveal hidden power

A vast catalog of wild flora highlights specialized treatments for severe internal and external ailments. King Juba discovers the fleshy euphorbia plant on Mount Atlas, while aquatic plants like nymphæa regulate reproductive faculties and induce temporary impotence. Coastal succulents like crethmos are harvested from rocky shores to relieve strangury, clear kidney humours, and enrich rural peasant meals.

• Human nature manifests magical sympathies

The examination shifts to human biology, asserting that human bodily secretions and specialized lineages possess intrinsic supernatural powers. Members of the Psylli and Ophiogenes tribes neutralize serpent venom by physical touch, while Egyptian villagers put Nile crocodiles to flight with a shout. Roman citizens employ written charms, nail parings, and linen-wrapped flies to transfer fevers and ward off ophthalmia.

• Foreign beasts supply potent essences

Exotic animals provide powerful therapeutic substances derived from their blood, organs, and bodily excretions. Elephant blood alleviates consumption and lion gall acts as a strong dispersive agent for internal swellings, while bull's gall possesses enough intensity to turn copper surfaces golden. In contrast, horse gall and fresh bull's blood are classified as lethal human poisons.

• Domestic animals absorb human suffering

The narrative examines domestic animals as biological conduits for drawing disease directly out of the human frame. Small dogs and sucking whelps placed upon a patient's stomach absorb fatal visceral ailments into their own bodies, perishing so the human may recover. Diets of roasted African snails, kid's rennet, and deer antler ashes expel tapeworms and heal intestinal ulcers.

• Greek physicians monetize the art of medicine

A critical historical retrospective traces the evolution of medicine from divine origins to lucrative commercial practice. Hippocrates establishes clinical medicine after allegedly copying and burning temple records at Cos, while his successors earn fortunes treating royal clients. Competing medical sects like the Empirics in Sicily attempt to ground medical theory in direct observation and practical experiment.

• Insects and birds offer strange counter-poisons

The investigation details how humble creatures like bedbugs, house weasels, and common birds provide potent remedies against fatal toxins. Swallowing bedbugs protects domestic poultry from deadly asp bites, and house weasels preserved in salt neutralize snake venom. Male pigeon blood applied to the eyes clears bloodshot vision, and blinded swallow nestlings burned to ashes restore failing eyesight.

• Lethal springs warn of earth's hidden dangers

The scope broadens to inorganic natural marvels, documenting dangerous and miraculous bodies of water across the ancient Mediterranean world. Springs in Armenia nurture fatal black fish, while the icy waters of the Styx petrify whatever touches them. Boiling springs on Mount Soracte kill birds instantly, and corrosive streams in Thessaly dissolve iron and copper implements.

• Minerals and salts complete nature's bounty

The volume concludes with an exhaustive survey of natural salts gathered from oceans, inland lakes, and underground fossil mines. Salt varies wildly in visual color and texture, ranging from deep red Memphis salt to purple Sicilian crystals and fragrant saffron fossil salt from Cappadocia. Beyond seasoning food and stimulating grazing livestock, salt stands as nature's ultimate mineral remedy for human health.

The People

Hippocrates of Cos seeks to liberate medicine from secretive temple traditions and transform it into a standardized, clinical discipline. Hindered by the absence of systematic records and the insular nature of ancient religious shrines, he takes drastic action by copying down patient prescriptions from the temple of Aesculapius and allegedly burning the building to the ground. Through this aggressive act, he institutes clinical practice, forever changing medicine from an informal, sacred oral craft into an organized, highly profitable profession.

King Juba of Mauritania desires to establish his royal intellectual authority by exploring the natural world and expanding botanical science. Standing in his way are remote, inhospitable landscapes and uncataloged wildernesses like Mount Atlas. By conducting rigorous exploratory expeditions, Juba discovers the fleshy euphorbia plant, authors an influential botanical treatise on its medicinal virtues, and immortalizes his personal physician Euphorbus by naming the species after him.

Erasistratus, Prodicus, and the Hellenistic medical theorists seek professional prestige, wealth, and systemic dominance over competing medical schools. They are challenged by public skepticism, the limitations of early anatomy, and rivals who dismiss theoretical speculation in favor of pure empiricism. Through rhetorical skill and specialized subfields like iatraliptics, they end up radically transforming the economic standing of physicians, commanding vast fortunes—including Erasistratus receiving one hundred talents for curing King Antiochus—while entrenching medical practice within elite political circles.

The specialized lineages, including the Psylli, Marsi, and Tentyrites, desire to preserve their hereditary immunity and living traditions of controlling deadly animals. Their quiet existence is threatened by Roman imperial authority, which views their natural gifts with intense suspicion and subjects them to public verification. Figures like Euagon of the Ophiogenes end up thrust into public trials, such as being thrown into vessels of living vipers before Roman consuls, ultimately serving as living proof for Roman naturalists that human biology operates through innate physical sympathies and antipathies.

Empiric practitioners like Acron of Agrigentum want to strip medical practice of philosophical dogma and base healing entirely on observable trial and error. They are hindered by entrenched dogmatists and magical practitioners who rely on incantations and charms. They end up establishing a lasting rival school that prioritizes repeatable experimental evidence, leaving a permanent divide in classical medical philosophy.

In Its Own Voice

Pliny explains that botanical research has stagnated because rural gatherers lacked formal education while urban Romans relied passively on foreign physicians.

Such was the state of medical knowledge in ancient times, wholly concealed as it was in the language of the Greeks. But the main reason why the medicinal properties of most plants remain still unknown, is the fact that they have been tested solely by rustics and illiterate people, such being the only class of persons that live in the midst of them: in addition to which, so vast is the multitude of medical men always at hand, that the public are careless of making any enquiries about them.

The author defends documenting distasteful remedies by arguing that an editor must faithfully record how ancient authors understood natural sympathies.

There are some things, of a most revolting nature, but which are recommended by authors with such a degree of assurance, that it would be improper to omit them, the more particularly as it is to the sympathy or antipathy of objects that remedies owe their existence.

In evaluating superstitious magical prescriptions, the narrative details an elaborate folk ritual designed to transfer fevers from a sick individual onto a neighbor's house.

Take the parings of the toe-nails and finger-nails of a sick person, and mix them up with wax, the party saying that he is seeking a remedy for a tertian, quartan, or quotidian fever, as the case may be; then stick this wax, before sunrise, upon the door of another person—such is the prescription they give for these diseases!

What It's Really About

Underneath its sprawling taxonomy of plants, animals, and minerals, this work is fundamentally an inquiry into the hidden order governing physical reality. It argues that nature operates through an intricate web of cosmic sympathies and antipathies, where every organ, plant, and mineral possesses inherent forces capable of acting upon others. Pain and disease are framed not as isolated biological failures, but as physical disharmonies that can be corrected by introducing corresponding natural elements.

At the same time, the text engages in a philosophical critique of human greed, scientific secrecy, and intellectual hubris. It repeatedly questions why humanity fails to master available natural cures, pointing out how social elitism, medical commercialization, and the hoardings of practitioners hinder true progress. The narrative contrasts the pure utility of nature with human excesses, showing how necessary knowledge degrades into commercial exploitation or superstitious folly when unchecked by disciplined observation.

Ultimately, the book poses fundamental questions about authority and evidence: Should medical knowledge rest upon divine revelation, historical tradition, theoretical speculation, or empirical trial? By juxtaposing folk charms with empirical observations and historical anecdotes, the text exposes the tension at the heart of ancient science, caught between an earnest desire for empirical truth and a deep susceptibility to magical thinking.

Why Read It Today

This volume will deeply absorb historians of science, classical scholars, herbalists, and readers fascinated by how ancient minds attempted to structure human knowledge. Reading it feels like wandering through a vast, labyrinthine museum of the Roman world, where brilliant natural observations sit directly alongside startling folk magic and bizarre medical prescriptions. The prose moves with incredible momentum, shifting seamlessly from meticulous botanical breakdowns of ivy and oak mistletoe to sweeping historical critiques of greedy Greek physicians and strange tales of African snails, river monsters, and poisonous springs. By mapping every leaf, horn, and spring, it reveals an empire attempting to conquer mortality through exhaustive knowledge. What stays with you long after reading is the astonishing earnestness of the classical effort to comprehend nature—a relentless determination to find healing in every root, animal gland, and mineral crust.

However, prospective readers must prepare for significant stylistic and intellectual challenges. The narrative structure is intentionally exhaustive rather than plot-driven, functioning as a massive reference work that presents relentless lists of remedies for endless physical ailments. The nineteenth-century translation retains archaic terminology, Latin weight measures, and classical vocabulary that require patience to navigate. Furthermore, modern readers will encounter jarring period attitudes, including unabashed endorsement of magical sympathetic practices—such as transferring fevers using fingernail parings—and remedies involving animal sacrifice or revolting ingredients like crushed bedbugs and puppy entrails.

Yet these difficulties are precisely what make the work so valuable today. The text does not sanitize or modernize antiquity; instead, it presents the Roman worldview in all its strange, unvarnished complexity. It forces us to confront a world where empirical observation had not yet separated from religious magic, offering a rare, humbling reminder of how science evolves over centuries. Readers who embrace its dense cataloging will discover a remarkable portrait of human curiosity striving to find order, health, and meaning within an unpredictable natural world. It stands as a towering testament to antiquity's intellectual ambition.