The sailor's teeth wobbled in his jaw when he pushed at them gently with his tongue. A week later his teeth fell out, and his bloody gums erupted with boils. Exhausted, he was unable to drag himself from his hammock for his watch until the boatswain forced him to his feet by whipping him with a rope end. Once on deck, in the sunlight, the sailor saw that his old wounds and sores from years of work at sea, scars he thought had healed, had reopened. Worn out from climbing the ladder, he fell to his knees and then collapsed on the wooden deck. He was dead.
Those crewmates who had the strength arranged his funeral, such as it was: one man wrapped the sailor in an old scrap of sail and tied a few small cannonballs to his feet. A short prayer from the captain, a plank tipped over the rail, a splash. Deprived of a grave, the body rested on the ocean floor. One more sailor dead from scurvy, dead for the lack of a daily spoonful of lemon juice.
The scurvy deaths were perhaps the most tragic, as they could have been easily prevented. The specific cause of scurvy--a deficiency of vitamin C--was not discovered until the 20th century, but the knowledge that citrus fruit or cabbage (in the durable form of sauerkraut) could prevent the disease had been known to at least some sailors since the 16th century. For every man scurvy killed three were spared but left sick and weak, often scarred and toothless. By one estimate, crews too enfeebled by scurvy to control their ships were the cause of half of all the shipwrecks in history.
Physicians were stymied by the many manifestations of scurvy. It was not always understood that what appeared to be many different diseases afflicting the crew of a ship were, in fact, just one disease. When sailors went to shore and were cured of the disease, it was not clear what it was that had cured them. This confusion was part of why it took physicians so long to recommend a simple cure and a preventative, and why so many sailors, in the words of one of their own, "took their habitation among the haddocks."
Recommended cures for shipboard scurvy included keeping the crew dry and the ship clean; serving bread and diluted wine for breakfast; laxatives; sprinkling vinegar about the ship; burning tar; bleeding eight ounces of blood from the left arm; rice; rum punch; cooking in iron boilers instead of copper ones; wearing warm clothing in cold weather; drinking malt wort; and, in the case of Magellan's historic circumnavigation, eating the ship's rats. (It is now known that rats can synthesize and store vitamin C.)
Richard Hawkins was the first to realize, on a 1593 voyage to the Pacific, that introducing sour oranges and lemons to his crewmates' diet improved general health and saved lives
Seven years later, in 1601, Sir James Lancaster made all on board for his voyage to India take three spoonfuls of lemon juice every morning, also with life-preserving results. (At a stop in Madagascar to replenish the fruit supply, unfortunately, many of the crew "did devour immoderately" plantains and lemons, and died of dysentery.)
Bad air was often blamed for scurvy
In 1607, the English East India Company wrote in its minutes that "lemon water"--what we would call lemon juice--would be included in the provisions for future voyages, although the amount to be carried is not specified. Not all expeditions went out with it, however, and some that left home with lemon juice ran out, with resulting (but not surprising) deaths.
In 1736, the physician William Cockburn published a new edition of his book Sea Diseases, in which he declared that scurvy attacked the idle sailor.
During Commodore Anson's voyage from 1740 to 1744, one hundred and forty years after Lancaster served up lemon juice to his crew, half of the nearly two thousand men who embarked died. Anson's men had been careful to keep their ships clean, and the ports open, and had been able to catch plenty of rain water for drinking, so they were surprised by the huge number of casualties. What more could they be expected to do? News of the deaths on Anson's voyage shocked the English ship's surgeon James Lind, who was then inspired to perform the first controlled study of scurvy; the first controlled study in nutrition, in fact, and possibly the first in any clinical science.
Lind was on the man-of-war Salisbury and, while cruising the English Channel in 1747, he used some of the scurvy-stricken sailors as his subjects. Twelve men, with as close to the same symptoms as he could find, were confined and given the same diet. (Gruel with sugar for breakfast, broth with mutton or pudding for dinner; "for supper, barley and raisins, rice, and currants, etc.") He divided his subjects into six pairs, giving each a different suspected remedy every day for two weeks. The tested antiscorbutics were a quart of hard cider; drops of elixir vitriol; two spoonfuls of vinegar three times a day; half a pint of sea water; a paste of garlic, mustard sea, balsam of Peru, dried radish root, and gum myrrh; and, to the lucky pair, two oranges and one lemon.
The lemon-receiving patients improved after six days, at which time Lind ran out of fruit and they switched to elixir vitriol. At the end of the two weeks they were the healthiest of the subjects, followed by the men who drank hard cider. There was no improvement for the others.
Lind's 400-page Treatise of the Scurvy was published in the 1753. Read using hindsight and in the light of 20th century knowledge, Lind's Treatise is frustrating. He is so close to saving thousands of lives a year, but instead he decided that a damp climate and an unhappy disposition caused scurvy. (This brings to mind an image of a peg-legged pirate captain throwing towels to his crew and telling them to just cheer up.)