James Lind (1716 in Edinburgh – 1794 in Gosport) was the pioneer of naval hygiene in the Royal Navy. By conducting the first ever clinical trial, he proved that citrus fruits cured scurvy. He also proposed that fresh water could be obtained by distilling sea water. He also fought for the drying of ships by using better ventilation, improved the clothing and cleanliness of sailors, and introduced fumigation with sulphur and arsenic. By his work he also influenced practices of preventive medicine and good nutrition among British soldiers.
James Lind began as an apprentice of George Langlands, a fellow of the Royal College of Surgeons of Edinburgh. In 1739, he entered the Navy as a surgeon's mate, serving in the Mediterranean, off the coast of West Africa, and in the West Indies. By 1746 he had become surgeon of HMS Salisbury in the Channel Fleet. Two years later he retired from the Navy, wrote his MD thesis on venereal diseases, and was granted a license to practice in Edinburgh, Scotland. (citation neededed )
Scurvy is a disease now known to be caused by a deficiency of vitamin C, but in Lind's day, the concept of vitamins was unknown. Vitamin C is necessary for the maintenance of healthy and connective tissue. Its deficiency causes ulcers to form in the lower legs and feet, excessive bleeding, loss of teeth and hair, opening of old wounds, depression, hallucinations, blindness, and eventually death.
In 1740 the catastrophic result of Anson's circumnavigation attracted much attention in Europe; out of 1900 men, 1400 had died, most of them allegedly from having contracted scurvy. According to Lind, scurvy caused more deaths in the British fleets than French and Spanish arms.
Since the 1600s, it had been known that citrus fruit had an antiscorbutic effect, when a surgeon of the British East India Company recommended them, but their use wasn't widespread. Although Lind was not the first to suggest citrus fruit as a cure for scurvy, he was the first to study their effect by a systematic experiment in 1747. It ranks as one of the first clinical experiments in the history of medicine.
Lind thought that scurvy was due to putrefaction of the body which could be prevented by acids; that is why he chose to experiment with dietary supplements of acidic quality. In his experiment he divided twelve scorbutic sailors into six groups. They all received the same diet, and in addition group one was given a quart of cider daily, group two twenty-five drops of elixir of vitriol, group three six spoonful of vinegar, group four half a pint of seawater, group five received two oranges and one lemon and the last group a spicy paste plus a drink of barley water. The treatment of group five stopped after six days when they ran out of fruit, but by that time one sailor was fit for duty and the other had almost recovered. Apart from that, only group one also showed some effect of its treatment.
Shortly after this experiment Lind retired from the Navy and at first practised privately as a physician. In 1753 he published A treatise of the scurvy, which was virtually ignored. In 1758 he was appointed chief physician of the Royal Naval Hospital Haslar at Portsmouth. When James Cook went on his first voyage he carried wort (0.1 mg vitamin C per 100 g), sauerkraut (10-15 mg per 100 g) and a syrup of oranges and lemons (the juice contains 40-60 mg of vitamin C per 100 g) as antiscorbutics, but only the results of the trials on wort were published. In 1762 Lind’s Essay on the most effectual means of preserving the health of seamen appeared. In it he recommended growing salad, i.e. watercress (662 mg vitamin C per 100 g) on wet blankets. This was actually put in practice, and in the winter of 1775 the British Army in North America was supplied with mustard and cress seeds. Lind also continued to advocate citrus fruit. But because he – and most other physicians – still believed that their curative effect was due to the acid, it was reasonable to substitute them with cheaper acids.
It was Gilbert Blane who implemented citrus fruit. In an experiment in 1794 lemon juice was issued on board the Suffolk on a twenty-three week, non-stop voyage to India. The daily ration of two-thirds of an ounce mixed in grog contained just about the minimum daily intake of 10 mg vitamin C. There was no serious outbreak of scurvy. The following year the Admiralty took up the general issue of lemon juice to the whole fleet. This was not the end of scurvy in the Navy, as lemon juice was considered as a cure for scurvy and consequentially was dispensed by the ship's surgeon. Only after 1800 were the preventive qualities increasingly recognised.
For example, a frigate with 240 men, equipped with stores for four months, carried more than hundred tons of drinking water. Water quality depended on the original source of the water, the condition of the casks and for how long it had been kept. During normal times sailors were allowed to take as much water from a guarded butt as they wanted, but weren't allowed to take any water away. When water got scarce, it was rationed and rain water was collected with spread sails. Fresh water was also collected when an opportunity presented itself en voyage, but watering places were often marshy, and in the tropics infested by malaria.
In 1758, Lind discovered that the steam of heated salt water was fresh and tasted like rain water. He also proposed to use solar energy for the distillation of water. But only when a new type of cooking stove was introduced in 1810 did the possibility arise of producing fresh water by distillation on a useful scale.