James Lind

20 May 1747, in the fore-hold of HMS Salisbury

On 20 May 1747, aboard HMS Salisbury with the Channel Fleet, the ship's surgeon James Lind selected twelve sailors who already had scurvy and began a prospective comparison of six treatments.

He described putrid gums, spots, lassitude and weak knees. Eighty of the roughly 350 men aboard had been affected during ten weeks away from shore.

Lind housed the twelve together in the fore-hold and put them on a common basic diet — gruel, broth, puddings, biscuit, barley, raisins, rice, currants, sago and wine — before assigning the six pairs different supplements.

Six remedies, two men each

The treatments were cider, elixir of vitriol, vinegar, seawater, oranges and lemons, and a compound containing ingredients such as garlic, mustard seed, horseradish, balsam of Peru and myrrh. Each was a remedy already advocated in Lind's time.

The citrus pair received two oranges and one lemon a day for as long as supplies lasted. They lasted six days.

What the six days showed, and what they did not

By the time the fruit ran out, one citrus-treated sailor was fit for duty and the other had recovered enough to nurse the remaining sick men. Lind judged cider the next-best treatment.

The comparison held quarters and base diet constant, but Lind reported no random allocation, no concealment, no blinding, no placebo and no untreated group. All twelve subjects were already ill, so what he tested was treatment rather than prevention.

The finding stayed shipboard evidence until Lind published his retrospective account in the 1753 first edition of A Treatise of the Scurvy, where it occupied only a few pages. The 20 May date comes from that account, not from a surviving day-of-trial protocol.