Christmas 2016: In the Literature
    
            
BMJ
    2016;
    355
     doi: http://dx.doi.org/10.1136/bmj.i6516
    (Published 14 December 2016)
  
    Cite this as: BMJ 2016;355:i6516  
    
    
Dover’s
 Powder was introduced in the 19th century as a treatment for febrile 
illnesses and other ailments. The originator of the powder, Thomas 
Dover, was a man of many parts—doctor, privateer, rescuer of Alexander 
Selkirk (the inspiration for Daniel Defoe’s Robinson Crusoe), 
fashionable London physician, popular medical author for the general 
public, and self publicist.
Dover’s Powder
My
 father, a London GP, used to prescribe Dover’s Powder for me when I had
 various mild childhood febrile illnesses. This was probably common 
practice before and during the second world war. The preparation was a 
mixture of ipecacuanha, powdered opium, and lactose. It was available in
 Britain until the 1960s and in India until as recently as 1994. In many
 ways Dover’s Powder was an ideal preparation, its opium content having 
analgesic and soporific properties and a small dose of ipecacuanha 
having expectorant properties. However, opioid derivatives came to be 
considered unsuitable for minor illnesses, particularly for children. 
Dover’s Powder was used extensively during the American civil war, by 
Italian troops in the western desert, and during the second world war by
 the navy, in the coxswain’s box of medicines that was supplied to 
destroyers and smaller ships.1
Dover’s early years
Dover
 took his first degrees (bachelor of arts and then master of arts) in 
Oxford and then went to Gonville and Caius College, Cambridge, possibly 
because of the distinction of the master of the college, Robert Brady, 
who was regius professor of physic and a friend of Thomas Sydenham’s, a 
doctor who practised in Pall Mall. Sydenham was regarded as the English 
Hippocrates because of his ability to accurately record the natural 
history of disease. Dover became the house pupil of Sydenham and learnt 
the value of opium as a medication.2
While
 studying with Sydenham, Dover caught smallpox. Sydenham’s treatment 
consisted of cooling (no bed clothes and open windows), bloodletting, 
purging, and copious weak beer with “spirit of vitriol” (sulphuric 
acid). Not only did Dover recover, but he used this therapy on his 
patients, including seafarers. Surprisingly, many survived, although 
they may have had the milder strain (alastrim).
Dover’s 
bachelor of medicine was not recognised for practice within six miles of
 Westminster; for this a licence had to be obtained from the Royal 
College of Physicians. So Dover set up practice in Bristol; a thriving, 
wealthy city and a major sea port. About two thirds of Dover’s patients 
sought advice for fevers, most of which are now rare in the developed 
world, but many were, and still are, commonly encountered in developing 
countries. Many of Dover’s patients would have been sailors and traders,
 who caught infections or experienced trauma on long voyages to distant 
lands. Dover became wealthy in Bristol, but he also took care of the 
inmates of a workhouse (St Peter’s Hospital) free of charge.3
From physician to privateer
Unlike
 many wealthy merchants Dover not only financed privateering expeditions
 but also set out himself to plunder enemy ships and coasts. 
Privateering expeditions were aimed at shortening the war of Spanish 
succession (1701-14) by attacking the enemy’s commercial interests, 
particularly Spanish galleons.
He helped finance one of 
the most remarkable voyages, which was not only very long (over three 
years, starting in August 1708), but was also nearly free of accidents 
because it was so well prepared. The voyage accumulated more prize money
 than any comparable expedition in maritime history, and Dover took an 
active role. The voyage started with two ships, The Duke and The Duchess,
 and the expedition had a well respected, though young, 
commander—Captain Woodes Rogers (aged 29). William Dampier, a pilot and 
experienced navigator who had twice circumnavigated the globe, was also 
on board. Their route took them through the Atlantic to Cape Horn, along
 the South American coast, and across the Pacific (fig 1⇓).4
The
 ships were remarkably small, with a keel of about 80ft and a 25ft beam.
 Built for speed, they were poorly equipped for long distances and had 
crews of just over 100 people.5
 Dover was the ships’ doctor and president of the council of senior 
officers, deciding strategy and resolving disputes. He was also in 
charge of landing and boarding parties. The cramped conditions were 
ideal for the transmission of infectious diseases, such as smallpox, 
plague, dysentery, typhus, and arthropod-borne infections. Scurvy was a 
perennial problem on particularly long voyages, where fresh produce was 
unavailable. Unlike many seafarers, Rogers and Dover were aware that 
fresh produce was both preventive and curative for scurvy some 40 years 
before James Lind’s classical experimental studies.
Inspiration for Robinson Crusoe
One day the crew of The Duke
 saw a fire on one of the islands of Juan Fernandes, about 400 miles off
 the Chilean coast. Despite advice not to pursue, lest there were 
Spaniards, Dover took a party of eight to investigate. They found a 
hairy, wild looking man, clothed in goat skins: Alexander Selkirk, a 
Scotsman. The only other inhabitants of the island were goats and cats, 
left behind by previous ships; there was no Man Friday nor eight desert 
island discs.
Selkirk had been marooned there for four 
years having quarrelled with the captain of his ship about its 
seaworthiness. Selkirk was right—that ship sank with major loss of life.
 Dampier knew of Selkirk’s navigational ability and appointed him TheDuke’s mate.
The
 voyage lasted for three years and three months. We don’t know whether 
Daniel Defoe met Selkirk or Dover, but Defoe was obviously captivated by
 Selkirk’s widely publicised story and may have read Rogers’ account of 
the voyage, A Cruising Voyage Round the World, which was published in 1712. In 1719 Defoe’s work The Life and Surprising Adventures of Robinson Crusoe was published.
Dr Quicksilver
After
 returning to England in October 1711 Dover took a prolonged vacation in
 eastern Europe and Anatolia. While there he became convinced of the 
value of mercury as therapy for a variety of ills.6
 He was known as “Dr Quicksilver,” but whether any of his patients 
developed mercury poisoning is not recorded. Perhaps they died before 
the link could be established.
Dover was initially 
wealthy as a privateer but lost most of this money in the “south sea 
bubble.” He settled his debts by selling his inherited family estates. 
To accumulate wealth again Dover was keen to establish himself as a 
doctor with a lucrative London practice. Aged 61 he obtained a licence 
from the Royal College of Physicians, but this was hindered with 
bureaucracy. Firstly his bachelor of medicine certificate could not be 
found, then an examiner failed to appear, and, finally, the key for the 
container for the diploma seal was lost. He practised in some of the 
more fashionable parts of London, behaving pompously and being overtly 
critical of his colleagues.
He published his book The Ancient Physician’s Legacy to his Country
 in 1719, reviewing 120 diseases and running to eight editions. This was
 aimed at the general public and directed towards self diagnosis. It was
 available in most coffeehouses; perhaps it was a predecessor of the 
internet. This self laudatory book contained letters from grateful 
patients and polemics against his fellow physicians and apothecaries. He
 thought that apothecaries grossly overcharged and that his college was a
 “clan of prejudiced gentlemen.”3
 The General Medical Council did not yet exist, but Dover’s conduct was 
chastised by the Royal College of Physicians, the president of which was
 his student contemporary Hans Sloane.
Dover spent his 
declining years in the village of Stanway near Cheltenham. He died in 
April 1742, but, despite his adventures and the lasting popularity of 
Dover’s Powder, there are no memorials to this remarkable man. Before we
 are too critical of the standards of medicine in the early 18th 
Century, we should ask what our successors will say about our practice 
and behaviour in 300 years’ time.
Footnotes
- Competing interests: I have read and understood BMJ policy on declaration of interests and declare that I have no competing interests.
 - I am grateful for advice from Dr Tim Beattie, a maritime historian, Dr D N Phear, retired physician, The Middlesex Hospital, Dr J Banatvala, Southbank University, and Madeleine Banatvala, Queen Mary College, Paris.