Secret Cures of Slaves: People, Plants, and Medicine in the Eighteenth-Century Atlantic World

By Londa Schiebinger

“Engaging unique sources . . . Londa Schiebinger untangles the complex relationships between European and local physicians, healers, plants, and slavery.” —François Regourd, Université Paris Nanterre
 
In the natural course of events, humans fall sick and die. The history of medicine bristles with attempts to find new and miraculous remedies, to work with and against nature to restore humans to health and well-being. In this book, Londa Schiebinger examines medicine and human experimentation in the Atlantic World, exploring the circulation of people, disease, plants, and knowledge between Europe, Africa, and the Americas. She traces the development of a colonial medical complex from the 1760s, when a robust experimental culture emerged in the British and French West Indies, to the early 1800s, when debates raged about banning the slave trade and, eventually, slavery itself. 
 
Massive mortality among enslaved Africans and European planters, soldiers, and sailors fueled the search for new healing techniques. Amerindian, African, and European knowledges competed to cure diseases emerging from the collision of peoples on newly established, often poorly supplied, plantations. But not all knowledge was equal. Highlighting the violence and fear endemic to colonial struggles, Schiebinger explores aspects of African medicine that were not put to the test, such as Obeah and vodou. This book analyzes how and why specific knowledges were blocked, discredited, or held secret.
 
“In this urgent, probing and visually striking volume, Londa Schiebinger, one of the pioneers of feminist and colonial science studies, shifts our understanding of Enlightenment racial attitudes to the domain of the medical, making a vital contribution to the dynamic new wave of research on science and slavery in the Atlantic world.” —James Delbourgo, Rutgers University

• Language: English
• Publisher: Open Road Integrated Media
• Release date: Jul 18, 2017
• ISBN: 9781503602984

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Stanford University Press

Stanford, California

© 2017 by Londa Schiebinger. All rights reserved.

No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or in any information storage or retrieval system without the prior written permission of Stanford University Press.

Printed in the United States of America on acid-free, archival-quality paper

Library of Congress Cataloging-in-Publication Data

Names: Schiebinger, Londa L., author.

Title: Secret cures of slaves : people, plants, and medicine in the eighteenth-century Atlantic world / Londa Schiebinger.

Description: Stanford, California : Stanford University Press, 2017. | Includes bibliographical references and index.

Identifiers: LCCN 2016049163 (print) | LCCN 2016051270 (ebook) | ISBN 9781503600171 (cloth : alk. paper) | ISBN 9781503602915 (pbk. : alk. paper) | ISBN 9781503602984 (ebook)

Subjects: LCSH: Human experimentation in medicine—West Indies—History—18th century. | Slaves—Health and hygiene—West Indies—History—18th century. | Blacks—Medicine—West Indies—History—18th century. | Traditional medicine—West Indies—History—18th century. | Tropical medicine—West Indies—History—18th century.

Classification: LCC R853.H8 S347 2017 (print) | LCC R853.H8 (ebook) | DDC 610.72/408996073—dc23

LC record available at https://lccn.loc.gov/2016049163

Londa Schiebinger

SECRET CURES of Slaves

PEOPLE, PLANTS, and MEDICINE in the EIGHTEENTH-CENTURY ATLANTIC WORLD

STANFORD UNIVERSITY PRESS

STANFORD CALIFORNIA

For Robert

CONTENTS

List of Figures

Acknowledgments

Introduction

Medical Experimentation in the Atlantic World

Human Subjects

The Taxonomy of Experiments

The Colonial Crucible

The Circulation of Knowledge

The Problem of Sources

1. The Rise of Scientific Medicine

Experimentation in the West Indies

The Science of Skin Color, or the Physiological Niceties of Race

L’Homme Planté: Place Versus Race

2. Experiments with the Negro Dr’s Materia Medica

Bois Fer and the Circulation of Knowledge

The African Hypothesis

The European Hypothesis

The American Hypothesis

The Greater Atlantic Hypothesis

3. Medical Ethics

Ethics in Europe: To Help, or at Least to Do No Harm

Ethics in the West Indies: The Question of Slaves

Who Goes First? Experiments with Cold Water

Slaves: A Protected Category?

4. Exploitative Experiments

Quier’s Smallpox Experiments

Thomson’s Yaws Experiments

Soldiers and Sailors

Children and the Poor in Europe

Are Bodies Interchangeable? The Medical Context

5. The Colonial Crucible: Debates over Slavery

Obeah and Sorcery

Experiments with Placebos

Outlawing Slave Medical Practitioners

The Professional Exclusion of Gens de Couleur Libres

Are Bodies Interchangeable? The Colonial Context

Advocating Better Living Conditions

Experiments with Breeding

Conclusion: The Circulation of Knowledge

The European Colonial Nexus

The African Slave Trade Nexus

The Amerindian Conquest Nexus

Agnotology and the Atlantic World Medical Complex

Appendix: Featured British and French Doctors in the West Indies

Notes

Bibliography

Image Credits

Index

FIGURES

1. Atlantic World circa 1774.

2. The West Indies circa 1774.

3. The circulation of knowledge in the eighteenth-century Atlantic World medical complex.

4. Cap-Français, Saint-Domingue, 1779.

5. Analysis of race, Médéric-Louis-Élie Moreau de Saint-Méry.

6. Thermometer circa 1800.

7. The first of Colin Chisholm’s six experimental groups.

8. Colin Chisholm’s six experimental groups.

9. An early image of yaws.

10. Entry for bois de fer, Jean-Baptiste Pouppé-Desportes.

11. Bois de fer, Jean-Baptiste-Christophe Fusée-Aublet.

12. West Gondwana.

13. Negro Dr as knowledge broker.

14. William Wright (1735–1819).

15. Plan of the hospital for sick slaves, Good Hope Estate, Jamaica, circa 1798.

16. Edward Jenner’s lancet.

17. Burning of Cap-Français.

18. Elisha Perkins’s metallic tractors.

19. The European colonial nexus, the flow of knowledge between Europe and the Americas.

20. The African slave trade nexus, the flow of knowledges, diseases, people, medicines, and plants from Africa to the Americas.

21. The conquest nexus, Amerindian knowledge in the plantation medical complex.

22. Agnotological barriers in the Atlantic World medical complex.

ACKNOWLEDGMENTS

Writing history has changed. Over the years I worked on this book, vast resources became available online. My thanks to the diligent souls whose fingers are at times anonymously captured in the scans as they copy the pages of rare and valuable books, and to the Web designers who have improved the interfaces with these materials over the years. I have nearly an entire century and a half of rare books now downloaded to my own computer—and I can print out, mark up, and make notes on 250-year-old texts! Rather than traveling to Paris, Aix-en-Provence, London, Edinburgh, Jamaica, and beyond, scholars now have valuable texts at their fingertips. Texts can be consulted many times, perused without taking copious handwritten notes, searched, and generally enjoyed. Images are printable. Much can be learned by searching Eighteenth-Century Collections online—what a resource! Although one loses the tactile pleasure of eighteenth-century papers and leather bindings, one does not miss the mold, dust, jet lag, and hours waiting for things to be delivered to the reading-room table. Now one can read Jean-Barthélemy Dazille while taking breaks to do laundry (the benefits—physical and intellectual—of interspersing heavy-duty research and writing with mundane chores should not be underestimated). Nothing, of course, replaces travel to the places where the history was made to experience firsthand the people, sights, sounds, heat, and complexity of various environments. And nothing substitutes for research in the archives and talks with knowledgeable librarians and archivists.

Many thanks are due for the making of this book. My imagination was jolted and my learning advanced during my sabbatical year at the Stanford Humanities Center, where new ways of visualizing historical data have sprung up in the past decade. I benefited greatly from my colleagues there—especially Caroline Winterer, Nicole Coleman, Paula Findlen, and Dan Edelstein—who have devised new ways to map the Republic of Letters. Seeing data is exciting, and this book represents my first attempts at mapping the circulation of people, plants, and medicine in the Atlantic World. None of this would have been possible without my collaboration with Erik Steiner, Codirector of the Spatial History Project at the Center for Spatial and Textual Analysis (CESTA), Stanford University. Erik took my raw concepts and rendered them with visual elegance. Across this entire process, he provided exacting technical skills, frameworks, and guidance along with much good humor. It was difficult reducing what might have been beautifully layered colored images to two dimensions in black and white for print on paper. I might have done a complete Web production (similar to genderedinnovations.stanford.edu), but since this is a history project I have chosen a traditional mode of intellectual conveyance. Books are still wonderful to hold in your hand.

My thanks go, too, to the Alexander von Humboldt-Stiftung for support for the research freedom that started this project. Lorraine Daston’s gracious hospitality during my stay at the Max-Planck-Institut für Wissenschaftsgeschichte and the excellent Moral Authority of Nature group made for an auspicious beginning. I thank the National Science Foundation (grant no. 0723597) and the National Library of Medicine, National Institutes of Health (grant no. 1162326), for supporting this work. Any conclusions are mine and do not necessarily reflect the views of the NSF or NLM. A special thanks to Marcella Phillips, National Archives of Jamaica; the very helpful Biodiversity Heritage Library; the Wellcome Library; Drew Bourn, Historical Curator, Stanford Medical History Center, Lane Medical Library; and Mary Munill, Interlibrary Borrowing, Stanford University Libraries.

James Delbourgo, James McClellan, and François Regourd offered excellent comments on the manuscript. Other colleagues and audiences also thought along with me throughout the process. These included Mary Pickering, my dear friend from graduate school; Hal Cook and his Early Modern Drug Trade in the Atlantic World Conference, Wellcome Trust Centre for the History of Medicine at University College London; Bernard Bailyn and the International Seminar on the History of the Atlantic World, Harvard University; Theresa Levitt and Deirdre Cooper Owens, who organized the Porter Fortune Symposium on Science, Medicine, and the Making of Race, University of Mississippi; the Historisches Seminar, Johann Wolfgang Goethe-Universität, Frankfurt; and Paula Findlen, who directed the Empires of Knowledge: Scientific Networks in the Early Modern World workshop at Stanford University. A special thanks to the many patient students who read large portions of this book in seminar and offered helpful comments; to Hannah LeBlanc, who helped with notes and bibliography; and to Halley Barnet, who did some last-minute research for me in Paris.

Earlier versions of portions of this book have been published elsewhere as Human Experimentation in the Eighteenth Century: Natural Boundaries and Valid Testing, in The Moral Authority of Nature, ed. Lorraine Daston and Fernando Vidal (Chicago: University of Chicago Press, 2003), 384–408; Scientific Exchange in the Eighteenth-Century Atlantic World, in Soundings in Atlantic History: Latent Structures and Intellectual Currents, 1500–1825, ed. Bernard Bailyn (Cambridge, MA: Harvard University Press, 2009), 294–328, reprinted in Waltraud Ernst, ed., Ethik—Geschlecht—Medizin: Körpergeschichten in politischer Reflexion (Berlin: LIT, 2010), 41–69; Medical Experimentation and Race in the Eighteenth-Century Atlantic World, Social History of Medicine 26, no. 3 (2013): 364–82, reprinted in The History of Science, ed. Massimo Mazzotti (London: Routledge, 2015); and The Atlantic World Medical Complex, in Empires of Knowledge: Scientific Networks in the Early Modern World, ed. Paula Findlen (New York: Routledge, forthcoming). I thank these journals, editors, and presses for their interest in my work.

Finally, to Robert Proctor, Geoffrey Schiebinger, and Jonathan Proctor, as always, my love.

INTRODUCTION

These Observations determined me to try some Experiments.

—A. J. Alexander, planter, Bacolet, Grenada, 1773

IN 1773, AN EXTRAORDINARY EXPERIMENT pitted purported slave cures against European treatments in Grenada, a small island south of Barbados, just off the coast of South America (figure 1). The planter Alexander J. Alexander’s experiment with his Negro Dr’s Materia Medica, as he styled it, reveals how Europeans tested and evaluated what they deemed slave cures. The disease in question was yaws, a bacterial infection that produces horrid ulcers and lesions in its victims and, in advanced stages, excruciating pain, especially in the hands and feet. Yaws thrives in humid, tropical areas where overcrowding and poor sanitation prevail. Needless to say, slaves throughout the West Indies were plagued by it. Planters took note because slaves with yawey feet often could not walk and hence could not work. Jamaican physician James Thomson wrote, Any proprietor of Negroes is well aware of the loss he sustains from the yaws. . . . The finest looking slave will . . . in a few months become a burden to himself and his master.¹

This book analyzes the eighteenth-century Atlantic World medical complex from the 1760s, when a robust experimental culture emerged in the British and French West Indies, to the early 1800s, when debates raged about banning the slave trade and, eventually, slavery itself. Three questions motivate this work. A first investigates the circulation of knowledge in the Atlantic World. When A. J. Alexander tested his slave’s medicine, what was he actually investigating? African cures transported to the Americas? Remedies developed by Amerindians—Arawaks, Tainos, and Galibis or Kali’na—and transmitted to African slaves, who, unlike Europeans, were familiar with what we today call tropical medicine? Cures developed by plantation slaves in the Americas? Or, by some great twist of irony, cures communicated by the French to the slave via the plantation complex?

A second overarching question digs into the ethics of experiments using enslaved bodies. How were human subjects chosen for experimentation? What ethical brakes kept scientific enthusiasm from overwhelming vulnerable populations?

Figure 1. Atlantic World circa 1774. The Atlantic Ocean is not an empty space but alive with winds and currents that influenced merchant shipping lanes, patterns of the slave trade, and, ultimately, the circulation of knowledge among its littoral regions. The currents are broadly circular, allowing European ships passage to Africa, then sweeping them on to Brazil, the Caribbean, and North America before propelling them back to Europe. Plying directly from the West Indies to Africa was nearly impossible.

A third question investigates race and the interchangeability of bodies. What notions of uniformity and variability across living organisms drove the testing of new drugs and medical techniques? Were tests done on white bodies thought to hold for black bodies (and vice versa)? Were male and female bodies considered interchangeable in this regard? We must remember that these were not purely scientific queries but questions fired in the colonial crucible of conquest, slavery, violence, and secrecy.

The sun-drenched sugar islands of the West Indies provide a fascinating setting for this study (figure 2). Still in the eighteenth century there was a robust mix of and competition between Amerindian, African, and European diseases, medicines, and practitioners. The West Indies—the string of islands in the Caribbean that constitute the Greater and Lesser Antilles—were embedded in what I call the Atlantic World medical complex. Here I borrow from Philip Curtin’s notion of the plantation complex. For Curtin, the plantation complex—stretching from Bahia, Brazil, to Charleston, South Carolina—was an economic and political order centering on slave plantations in the New World tropics.² We add to Curtin’s analysis the medical order that melded people, plants, and their knowledges in the Atlantic World. Europe dominated the medical complex as it did the plantation complex economically, politically, and militarily, yet people, goods, labor, food, timber—and, we will add, disease, knowledge, and medical remedies—moved promiscuously between continents, masters and slaves, and imperial monopolies. Here we examine the dynamics of the Atlantic World and how that larger medical complex shaped experimental practices on the ground in the Caribbean.

Figure 2. The West Indies circa 1774. This book focuses on British territories, including Jamaica, Grenada, and Saint Christopher, and French territories, including Saint-Domingue (renamed the Republic of Haiti in 1804), Guadeloupe, Martinique, and Cayenne in French Guiana. Jamaica and Saint-Domingue were the most valuable eighteenth-century sugar islands and, consequently, hubs of plantation medicine and experimentation.

MEDICAL EXPERIMENTATION IN THE ATLANTIC WORLD

In step with the broader culture of experimentalism that arose across Europe in the seventeenth and eighteenth centuries, physicians in both Europe and its colonies developed new standards for observation and experimentation in medicine. Since antiquity, physicians and healers of all sorts had tried new and untested cures in the regular care and management of patients, and especially in desperate situations. By the late eighteenth century, however, as the historian Andreas-Holger Maehle has shown, medical treatments were increasingly tested according to a set of procedures—what we today call protocols—agreed upon by the European medical community at large. Physicians at the time self-consciously labeled these procedures trials or experiments, essais, épreuves, or expériences, and even controlled experiments (Regeln [sic] Versuche). Francis Home, royal physician and professor at the University of Edinburgh, wrote in his Clinical Experiments that real experiments . . . tend to make medicine as certain as most other sciences.³

While modern medical regimes have deep historical roots, eighteenth-century experimental practices differed significantly from those of today. Early modern experimental trials were not randomized, and although the historian of medicine Ulrich Tröhler has reported some therapeutic blind trials, they were not double or triple blind. By and large, experiments did not employ placebos, even though what would eventually be called the placebo effect was well understood (chapter 5). Physicians sparingly employed statistical or probabilistic statistical methods.⁴

Historians have begun to rigorously investigate experimentation in the eighteenth century. The canonical experiments are well known: the Newgate Prison experiment in 1721 launched the testing of the smallpox inoculation in Britain; James Lind’s 1747 controlled study of twelve sailors demonstrated that oranges and lemons could prevent and cure scurvy; John Hunter’s 1767 self-inoculation with gonorrheal pus proved that the disease was transmissible; and Edward Jenner’s 1798 experiments established the value of vaccination against smallpox. Historian Rolf Winau has examined to what extent eighteenth-century experimental practices were controlled and repeatable.⁵

This book examines medical testing with humans in French and British West Indian colonies. Colonial drug testing and human experimentation were driven by physicians’ desire to create scientific medicine. Tropical disease—a term that arose in this period—was something new to Europeans, and physicians struggled to find cures in the face of massive mortality.⁶ Thomas Dancer, longtime physician in Jamaica and island botanist, warned that whatever the merit of medical books imported from Europe, their findings are not so well suited to . . . tropical climates, where diseases put on a different aspect and character; where they commonly run a shorter course, and have a more fatal tendency.⁷ Fine educations in Europe could not guarantee success on the ground in the tropics.

I have written extensively elsewhere about European bioprospecting in the West Indies for Amerindian and African cures.⁸ Europeans, from the sixteenth through to the end of the eighteenth century, tended to value medical knowledge of the peoples they encountered around the world, including that of Africans and Amerindians. With the decline of Amerindian populations in the Caribbean, slave medicines took on an unexpected importance, even though in the first half of the eighteenth century Africans on the big sugar islands were no more native to the area than Europeans (at least 80 percent had been born in Africa). Unlike Europeans, however, Africans knew tropical diseases, their prevention, and their cures. Here we delve into how various new remedies were tested.

We must keep in mind that physicians’ desire to develop new cures in the Caribbean was largely driven by the political and economic ambitions of European states. Medicine of warm or tropical climates was necessary to keep slaves—as valuable commodities of powerful masters—alive on West Indian plantations. Tropical medicine was also required to keep large populations of soldiers and sailors healthy and ready for combat. In his Treatise on Tropical Diseases; or on Military Operations, Jamaican surgeon Benjamin Moseley highlighted how the failure of European cures led to political defeat. It was chiefly owing to the ravages of . . . [dysentery] in the French armies, Moseley wrote, that the English islands were not invaded earlier; and it was also owing to the same cause, that the English forces were, in many instances, unable to defeat their enemies. Moseley developed a cure for dysentery while stationed in the West Indies—a cure that was implemented everywhere that Britain had troops. Yellow fever also wreaked havoc when the British attempted to invade and take Saint-Domingue during revolution in the 1790s. The invasion was beaten back primarily by mortality rates as high as 70 percent—not by soldiers’ guns and bayonets.⁹

HUMAN SUBJECTS

Finding new and effective cures requires testing new drugs in living organisms. A perennial question for doctors, patients, and ethicists is: Who will go first? On whose body will unknown and potentially dangerous drugs be tested? By whom, and for whose benefit? Today, such questions are mediated through carefully crafted codes of patients’ rights (chapter 3). Here we explore how drugs were tested in the eighteenth century, and specifically how human subjects were chosen for experiments.

In early modern Europe many poor souls were subjected to medical testing. Drug trials tended to overselect subjects from wards of the state, such as prisoners, hospital patients, and orphans. Most experimental subjects came from the same groups used for dissection: that is, persons with no next of kin to insist on Christian burials or, in the case of medical care, to seek out and pay for expensive cures. Because it was thought that these subjects owed their well-being to the state, it was generally accepted that they should repay their debt and benefit society more generally by being used in medical testing. Nine children from the Hôpital de la Pitié, for example, were used in an experiment for a remedy for the itch in the 1780s. As was often the case in experiments that were recorded, all were perfectly cured. (Publication bias to record only positive results ran rampant.)¹⁰ In addition to charity patients, physicians used their own bodies to evince their confidence in a cure and, rarely, royal bodies to promote public health measures, such as inoculation for smallpox. Experimentalists generally assumed an interchangeability of bodies, so that testing on charity patients was thought to provide valuable data for physicians’ private practice among the wealthy.

One population not available in Europe and used in colonial experiments was slaves. The question of underrepresented minorities in medical experimentation is still volatile today: minorities, especially African Americans in the United States, tend to be simultaneously underrepresented in medical research and historically exploited in experimentation.¹¹ As the ethicist Robert Baker has written, modern bioethics arose from the need to protect vulnerable subjects, such as racial minorities, the economically disadvantaged, the very sick, and the institutionalized, who may be recruited as research subjects because of their dependent status and their frequently compromised capacity for free consent or because they are easy to manipulate as a result of their illness or socioeconomic condition. The 1979 Belmont Report was issued as a response to researchers’ exploitation of vulnerable populations, most notably the six hundred impoverished Alabaman African American sharecroppers recruited by the US Public Health Service in its Tuskegee Syphilis Study (1932–72). This study followed the natural progression of untreated syphilis in rural African American men, 399 of whom suffered from the disease and went untreated even after penicillin became widely available.¹²

The legacy of Tuskegee and other abuses persists today among many African Americans, who are understandably reluctant to participate in clinical trials. Some African Americans believe that researchers (the majority of whom are white) will expose them to unnecessary risk; others doubt that they, as a group, will benefit from the research. Yet US federal law requires that minority populations be included in clinical research to support their health and well-being.¹³

Historians of the US South have emphasized that slaves were exploited in medical experiments and dissections. Historian Todd Savitt’s excellent work has carefully documented that physicians in the American South, especially in the nineteenth century, often took advantage of African Americans by testing new techniques and remedies. In several instances, Savitt tells us, physicians purchased blacks for the sole purpose of experimentation. Though white subjects were included in some experiments, blacks constituted the overwhelming majority. The power of the master joined to the authority of medical men tended to render slaves vulnerable. Blacks were considered more available and more accessible in this white-dominated society, Savitt has concluded. They were rendered physically visible by their skin color and were legally invisible because of their slave status.¹⁴

Experimentation and the use of human subjects are specific to particular times and places. This book investigates medical practices in the late eighteenth-century Atlantic World. A major finding of this book is that, in many instances, European physicians in the British and French West Indies did not—as might be expected—use slaves as guinea pigs. Slaves were considered valuable property of powerful plantation owners whom doctors were employed to serve. The master’s will prevailed over a doctor’s advice, and colonial physicians did not always have a free hand in devising medical experiments to answer scientific questions. The overarching motive was economic: the profitability of the plantation complex depended on slave labor (chapter 5).¹⁵ Importantly, as we shall see, clinical wards of medical schools—epicenters of medical testing in Europe and the American South—were not established in the Caribbean in this period (chapter 1).

Persons of African descent in the Caribbean may have become more vulnerable after emancipation, when doctors had no masters to answer to. Discussing the legal status of free people of color, Jamaican Robert Renny stated that they were placed in a worse situation than slaves, who have masters interested in their protection.¹⁶ Much of Renny’s sentiment, however, was informed by his loyalty to the British crown and the colonial enterprise.

As we shall also see, some experiments with slaves in the eighteenth century were exploitative (chapter 4). But it is important to emphasize that in the eighteenth-century West Indies strong parallels emerged between slaves, soldiers, and sailors—as large populations in economies of few resources. Medical men might serve both populations—soldiers and sailors in time of war, and slaves in time of peace. Health was precarious: in desperate situations, physicians serving large populations often experimented with new remedies as a last resort.

THE TAXONOMY OF EXPERIMENTS

To what extent were slaves exploited in eighteenth-century West Indian experiments? To answer this question I develop a taxonomy of the varieties of experiments within the context of eighteenth-century medical ethics: exploitative (taking undue risk with human life) versus nonexploitative (testing with care in the group likely to benefit from the cure); invasive versus noninvasive; therapeutic to the individual involved versus nontherapeutic. Today informed consent would also be a key consideration in judging the exploitative nature of experiments. This, however, was not the case for experimental populations—the poor, soldiers, sailors, or slaves—in the eighteenth century. It was enough that physicians judged the treatment to be in a subject’s best interest. Although patient consent was not required, physicians often complied with patients’ or parents’ wishes (chapter 3).

Chapter 1 focuses on two sets of experiments and how race was investigated in each: those by the Jamaican physician James Thomson, searching specifically for anatomical and physiological differences between the races, and those by Colin Chisholm, inspector general for troops in the British West Indies, examining human constants in both blacks and whites across temperature zones.

James Thomson is a complex character. The historian Richard Sheridan praised him for seeking to blend the best elements of African and European cultures. And, as we shall see throughout this book, Thomson was a strong advocate of Africans and their medical knowledge. Intimating his closeness to slaves, he insisted that physicians should consider patients’ wishes, when they do not materially interfere with the actual state of disease.¹⁷ Yet Thomson engaged in a grotesque set of experiments to understand skin color through dissection of persons of African origin. I focus on this experiment—done late in the period we investigate here—because it is what we expect to find. Motivated by debates on racial difference taking place in Europe, Thomson mounted a search to locate the ultimate physiological source of blackness in human skin. Thomson’s were among the most detailed experiments in the Caribbean at this time aimed at understanding racial differences.

Colin Chisholm, naval inspector and plantation owner in Demerara (later part of British Guiana) on the coast of South America, designed experiments to understand basic human nature and not, like Thomson’s, to uncover racial difference. Chisholm’s study included race as a variable, but his focus was place, specifically the birth and immigration status of patients. Were they born in Europe or Africa, and had they subsequently immigrated to the West Indies? Were they newly arrived or residents of long standing? Were they West Indian Creoles (persons of European or African origins born in the islands)? For Chisholm, these, and not race per se, were important factors predicting health.

Employing newly developed thermometers, Chisholm’s experiments were designed to answer questions crucial to the colonial enterprise. Specifically, he sought to determine whether animal heat changed dramatically with climate and whether a period of habit or assimilation was required for humans to regain their internal equilibrium. Chisholm’s experiments were not intended to be therapeutic. They were noninvasive (measuring only axillary temperature) and nonexploitative in the sense that they did not take undue risk with human life.¹⁸

Chapter 2 turns to experiments to test the enslaved African’s cure for yaws featured in A. J. Alexander’s experiment. One of my purposes in this book is to expand our knowledge of African contributions to science. Alexander considered his slave’s cure for yaws Negro Materia Medica.¹⁹ And indeed historians often write about slave medicine, tending to assume an African origin of a particular cure. One question we will explore is whether Africans brought their medicines and techniques with them from their homelands or whether they experimented with new plants and cures found in the West Indies. This raises methodological questions about how to trace the circulation of knowledge in the Atlantic World. In chapter 2, we attempt to identify the provenance of Alexander’s slave cure. When documents fail, I turn to the plants in the Negro doctor’s cure: Were they indigenous to Africa? The Americas? Or both? What can the plants tell us?

Alexander’s experiment was designed to test a cure, in this case for yaws. Ethicists at the time accepted that therapeutic experiments were permissible when commonly used medicines failed, which was often in the tropics. Edinburgh physician John Gregory stated in his medical lectures that desperate measures should be used in some cases, where every other method has been proved ineffectual. In such circumstance we should have recourse to medicine which under more favourable circumstances might be thought dangerous.²⁰ (Gregory’s were lectures that numerous physicians in the British Caribbean would have known about because the vast majority