Hektoen International

A Journal of Medical Humanities

The ships’ surgeons’ toxic toolkit

Richard de Grijs
Sydney, Australia

Mercury ointment applied to a patient’s legs
. Paracelsus, Wundartzeney die Frantzosen genannt, I; Frankfurt, 1562. Out of copyright.

During the “Age of Sail,” months-long voyages gave rise to unique health concerns.1,2 Moreover, ships’ surgeons frequently encountered diseases brought upon uninhibited sailors through their own “adventurous” behavior. Following their arrival at far-flung ports, sailors often returned from shore visits with more than they bargained for, including sexually transmitted diseases like syphilis.

Descriptions of syphilis—grande verole, lux venereal (or “lues”), the “great pox”—first appeared following the invasion of Naples (Italy) by the French army of Charles VIII in 1495, when a devastating new epidemic disease rapidly spread among his soldiers.3 However, literary and religious works suggest that syphilitic afflictions may have simmered in Europe at much earlier times.4,5

In his celebrated poem, Syphilis sive morbus gallicus (Syphilis, or the French disease; 1530), the Italian physician Girolamo Fracastoro (Hieronymus Fracastorius; 1476/8–1553) highlighted the symptoms that made the disease particularly gruesome:

The most subtle of these morbid humors … take refuge either in the skin or in the extremities of the limbs. They … produce hideous eruptions on those points and these exanthems [widespread rashes] soon spread over the whole body and cover the face with a repulsive mask.6

Within weeks of “seeing a girl,” infected sailors would begin to display rashes, fever, and painful genital sores,7 soon followed by foul, repulsive abscesses and chancres (ulcers). In his 1765 surgical textbook, Richard Brookes (fl. 1721–1763) therefore recommended that “amorous Dalliance with Women … should be shunned like Death.”8

Paracelsus (c. 1493–1541), the “Father of Chemistry,” provided perhaps the best contemporary clinical description of the disease in his 1536 treatise Der grossen Wundartzeney (The Great Surgery Book). He favored heavy metals—mercury, lead, arsenic, and copper sulphate—as treatment agents for various diseases. To treat syphilis, he promoted applications of mercury. Mercury had been used to mitigate epidemic fallout since Guy de Chauliac (c. 1300–1368), personal physician to the Pope in Avignon (France), had recommended its use in 1363 in La Grande Chirurgie.9 Yet, the compound had already been administered since ancient times to treat skin diseases and other conditions. It was also commonly used to purify the drinking water on ships.

Urethral syringe recovered from the pirate Blackbeard’s ship Queen Anne’s Revenge, which shipwrecked off the North Carolina coast in 1718. Chemical analysis shows that the syringe contained mercury. Photo by North Carolina Department of Cultural Resources. Public domain.

Initially, Paracelsus advocated ingesting mercury in the form of an elixir. However, its toxicity soon forced him to administer it as an inunction (an ointment rubbed into the skin), as suffumigation (inhalation of and bathing in mercury fumes), or both. Mercurous chloride, known as “calomel,” was developed in the late nineteenth century as a purgative and laxative agent; it was initially applied as an ointment. Until the early twentieth century, mercury treatments were also frequently administered as urethral injections using bone syringes. Injections of the caustic mercury solution mainly aimed to flush out the urethra and bladder. Multiple, often painful and uncomfortable courses, spanning weeks to years, would be required before one was deemed cured.10 The infected sailors’ lewd activity was, hence, popularly and mockingly referred to as “A night with Venus, and a lifetime with mercury.”11

The British Army’s physicians preferentially prescribed calomel treatment.12 In the Royal Navy, however, contemporary treatments of syphilis and most other common diseases and conditions—consumption (tuberculosis), scurvy, toothache, constipation, apoplexy, parasitic infection (worms), pregnancy, depression—were usually administered by ingestion of the “Blue Pill”13:

Bleeding, blistering and purging causes most types of fever to cease and if needed one should then give mercury, calomel or blue pill either with or without mercury. (Sir William Burnett, Director-General, Royal Navy Medical Department; 1846).14

In the navy, indeed, the practice of administering mercury is so uniform that it rarely becomes a question whether it is necessary in any individual case; and the patient is forthwith subjected for every species of genital affection succeeding to sexual intercourse … whether recent or remote, to a mercurial course, to be renewed if the inguinal glands become subsequently affected, and repeated again and again if other symptoms appear, or the original affection returns, until at length the surgeon … not knowing whether he has to treat a mercurial or a syphilitic disease, finds it necessary to recommend a change of air, decoction of sarsaparilla [a soft drink], and alternative doses of blue pill.15

Mercury was an important ingredient of the blue pill. It was often combined with licorice root, rosewater, dried rose petals, althaea (marshmallow), glycerol, sugar, and honey. Patients were directed to take one pill twice or three times a day. For each pill ingested, a patient would absorb 750 μg of mercury,16 so a standard daily dose contained more than one hundred times the mercury concentration considered safe today.

Mercury became the third most prescribed medicine, after opium and morphine, between 1854 and 1887.17 It is, however,

easily absorbed in the body, travels within to the kidneys, poisons the blood-filtering structures and causes renal failure. It is bound easily to the sulphur atoms of proteins and inactivates them … This poisoning inactivates diverse processes in the body—food digestion and absorption, growth and development, sensory perception, nerve conduction and brain function.18

As with repeated injections of mercury compounds, prolonged and repeated ingestion of blue pills led to complications. Those were usually attributed to the original disease, however. In the seventeenth century, treating a patient with mercury until he started to salivate was considered a sign of success19,20; it showed that the body had started to purge itself. Most physicians believed that diseases could be purged from the body by administering large quantities of drugs that enhanced the secretion of bodily fluids.21

Today, we know that excessive salivation is evidence of mercury poisoning.22 Other common symptoms of poisoning include irritability, anxiety, hostility, neuropathy (nerve damage), tremors, depression, insomnia, memory loss, tooth loss, mouth ulcers, violent gastrointestinal irritation, kidney failure, and dexterity problems. Mercury-based treatments naturally caused significant concern:

More infants are destroyed by the pestal [sic] and mortar than Herod slew. Scarcely a child can reach one year without being poisoned … All the quackery in the world comes from the regulars’ dispensatories.23

Memory will recal[l] to every old surgeon numbers of aggravated cases of secondary disease subsequent to the most liberal use of mercury in the primary affection.24

Medical practice during the Age of Sail still emphasized treating outward symptoms rather than the underlying causes. Physicians were encouraged to follow the teachings of the ancients, emphasizing Hippocrates’ theory of the Four Humors and, later, Galen’s early modern recommendations.25 Standard treatments included bloodletting; excessive bleeding frequently led to unintentional death, however.

The notoriously dangerous conditions on extended oceanic voyages made recruitment of qualified physicians challenging. Yet, desperate times called for desperate measures, and so despite their crucial, live-saving role, ships’ surgeons were not always formally trained. Thus,

physicians developed a small number of medically invalid therapies—like bloodletting, calomel, and blisters—that produced consistent and demonstrable changes in the patient’s physiological condition. Most … physicians used these standardized therapies almost exclusively, even though textbooks on therapeutics contained hundreds of alternatives. One physician stated in 1849 that for many physicians the lancet, mercury, antimony or opium, are the great guns that they always fire on all occasions.26

While the toxicity of mercury treatments was readily recognized, the dire consequences of exposure to mercury vapor became apparent only gradually. Fortunately, mercury vapor exposure was rare, despite the habitual decontamination of ships’ lower decks with mercury fumes. Indeed, as recently as 1911, the U.S. Public Health and Marine Hospital Service still recommended “that a vessel should carry for every 100 passengers: Bichloride of mercury, 5 pounds” as disinfecting solution.27

A major change in the Royal Navy’s appreciation of the dangers posed by exposure to mercury vapor occurred following the salvaging, by H.M.S. Triumph and H.M.S. Phipps, of a mercury cargo from a ship-wrecked Spanish vessel, possibly the Nuestra Señora de las Mercedes (Our Lady of Mercy), in March 1809:

An alarming illness broke out among the crews, all of whom were more or less salivated. The surgeons, pursers, and three petty officers, who were nearest the place where it was stowed, felt its effects the most; their heads and tongues have swelled to the most alarming degree … Every rat, mouse, and cock-roach on board has been destroyed, and the symptoms of general salivation have appeared in a strong degree.28

Many sailors involved in the salvage effort exhibited evidence of neurological trauma—tremors, partial paralysis, excessive salivation, mouth ulcers, tooth loss, gangrene of the face and tongue, and lung, bowel, and pulmonary complaints.29 They may have been exposed to mercury concentrations of more than 140 times the current maximum permissible level.30 The dangers of poisoning by a mercurialized atmosphere were popularized in Lewis Carroll’s Alice’s Adventures in Wonderland (1865), where the Cheshire Cat calls the Hatter and the March Hare “both mad”—specifically referencing the symptoms of dementia displayed by many contemporary felt hat makers.

By 1910, the quest for an effective, less toxic cure for syphilis started to bear fruit when the German physician Paul Ehrlich (1854–1915) discovered the anti-syphilitic properties of arsenic and developed arsphenamine (Salvarsan), the “magic bullet”31,32:

Arsenobenzol, designated “606,” … is now actually a more or less incredible advance in the treatment of syphilis and in many ways is superior to the old mercury – as valuable as this will continue to be – because of its eminently powerful and eminently rapid spirochaeticidal property.33

Eventually, the treatment with penicillin in 1943 of four patients suffering from primary syphilis sores at the U.S. Marine Hospital, Staten Island, New York, signaled the beginning of the end for mercury as a syphilitic treatment agent.34


  1. de Grijs R, 2021. “Plague of the Sea, and the Spoyle of Mariners”: A brief history of fermented cabbage as antiscorbutic.” https://hekint.org/2021/06/17/plague-of-the-sea-and-the-spoyle-of-mariners-a-brief-history-of-fermented-cabbage-as-antiscorbutic/.
  2. de Grijs R, 2023. “Temporary insanity in tropical waters.” https://hekint.org/2023/05/01/temporary-insanity-in-tropical-waters/.
  3. Frith D, 2012. “Syphilis – Its Early History and Treatment Until Penicillin, and the Debate on its Origins.” Journal of Military and Veterans’ Health, 20, 49–58.
  4. Garrison FH, 1929. An Introduction to the History of Medicine. 4th ed. Philadelphia PA, W. B. Saunders Co.
  5. Rolleston JD, 1934. “Venereal disease in literature.” British Journal of Venereal Disease, 10, 147-174.
  6. Fracastoro G, 1530. Syphilis sive morbus gallicus. Verona; English translation: https://ia600509.us.archive.org/15/items/hieronymusfraca00frac/hieronymusfraca00frac.pdf.
  7. Watson JC, 1801. Medical journal of H.M.S. Albion between 13th April 1799 and 2nd January 1801. PRO ADM 101 82/3 (U.K. Public Records Office).
  8. Brookes R, 1765. The General Practice of Physic …, Vol. 2. London, J. Newbery. P. 36.
  9. Schreiber W, and Mathys, FK, 1987. Infectio. Historia de las Enfermedades Infecciosas. Basel, Editione Roche.
  10. Gillett MC, 2009. The Army Medical Department 1917–1941. Army Historical Series. Washington DC, Center of Military History, United States Army.
  11. Dobson M, 2007. Disease: The Story of Disease and Mankind’s Continuing Struggle Against It. London, Quercus.
  12. Brockliss L, Cardwell J, and Moss M, 2005. Nelson’s Surgeon. William Beatty, Naval Medicine, and the Battle of Trafalgar. Oxford, Oxford University Press. P. 54.
  13. Gerard T, 2016. The “Blue Pill”. His Majesty’s Ship Acasta. http://www.hmsacasta.com/2016/09/the-blue-pill.html.
  14. Coulter L, 1963. Medicine and the Navy 1200–1900, Vol. IV: 1815–1900. Edinburgh and London, E&S Livingstone Ltd.
  15. Donnelly W, 1835. “Art. XI.—Facts and Observations regarding the Treatment of Venereal Diseases.” Edinburgh Medical and Surgical Journal, 35, 109–110.
  16. Hirschhorn N, Feldman RG, and Greaves IA, 2001. “Abraham Lincoln’s Blue Pills. Did our 16th president suffer from mercury poisoning?” Perspectives in Biology and Medicine, 44, 315-332.
  17. Flannery MA, 1999. “Another House Divided: Union Medical Service and Sectarians During the Civil War.” Journal of the History of Medicine and Allied Sciences, 54, 503–504.
  18. Markham JD (ed.), 2005. Napoleon and Doctor Verling on St Helena. Barnsley, Pen and Sword; cited by Holmberg T, 2005. https://www.napoleon-series.org/reviews/memoirs/c_verling.html.
  19. Frith, 2012. Op. cit.
  20. Brown K, 2015. The Seasick Admiral. Nelson and the Health of the Navy. Barnsley, Pen and Sword.
  21. Haller JS, Jr., 1997. Kindly Medicine: Physio-Medicalism in America, 1836–1911. Kent OH, Kent State University Press. P. 7.
  22. Falck ND, 1774. The seaman’s medical instructor. London, Edward and Charles Dilly.
  23. Hamilton AT, 1857. Notebook, 16 November 1857–11 April 1858; entry for 4 December 1857. http://civilwarrx.blogspot.com/2015/11/mercury-and-water-two-civil-war.html.
  24. Donnelly, 1835. Op. cit. P. 109.
  25. Clowes W, 1637. A Profitable and Necessarie Booke of Observations, … Last of all is adjoyned a short Treatise, for the cure of Lues Venera by Unctions and other approved wayes of curing …, 3rd ed. Londen, M. Dawson.
  26. Rothstein WG, 1992. American Physicians of the Nineteenth Century: From Sects to Science. Baltimore MD, Johns Hopkins University Press. Pp. 61-62.
  27. Supervising Surgeon General of the Public Health and Marine-Hospital Service of the United States, 1911. Annual Report for the fiscal year 1910. Vol. 39, p. 90.
  28. Medical Intelligence (No. XXIV), 1810. “Extract of a Letter from Lisbon, dated 12th May 1810, giving an Account of a singular Effect of the Fumes of Quicksilver, in the Crews of two Ships on that Station.” The Edinburgh Medical and Surgical Journal, 6, 513-514.
  29. Burnett W, 1823. “An account of the effect of mercurial vapours on the crew of His Majesty’s Ship Triumph, in the year 1810.” Philosophical Transactions of the Royal Society, 113, 402-408.
  30. Herzog N, and Niesel D, 20 June 2016. “Ships revealed mercury toxicity.” Abilene Reporter News. https://www.reporternews.com/story/life/columnists/norbert-herzog-and-david-niesel/2016/06/20/ships-revealed-mercury-toxicity/92295016/.
  31. Garrison, 1929. Op. cit.
  32. Frith, 2012. Op. cit.
  33. Neisser A, 1910. Die Behandlung der Syphilis mit dem Ehrlichschen Präparat 606. Deutsche Medizinische Wochenschrift, 36, 1889-1893; English translation: Benedek TG, n.d. Albert Neisser (1855–1916): Microbiologist and Venereologist. http://www.antimicrobe.org/h04c.files/history/Neisser.asp.
  34. Mahoney JF, Arnold RC, and Harris AD, 1943. “Penicillin treatment of Syphilis.” American Journal of Public Health, 33, 1387-1391.

RICHARD DE GRIJS, PhD, is a professor of astrophysics at Macquarie University in Sydney, Australia. He has a keen interest in the history of science and navigation. Richard is also a consultant, as well as a volunteer speaker and guide on the historical tall ships at the Australian National Maritime Museum.

Spring 2023 



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