Answer:
James Lind during his voyage and experiments at the sea used his medical expertise to develop a vaccine for scurvy.
Step-by-step explanation:
James Lind during his voyages across the ocean began to notice that the sailors suffered a strange disease. The patients started feeling weak, bleeding from the gums, edema, hypothermia, dry skin, progressing to internal bleeding and even death.
James Lind administered to the sailors concentrated citrus fruits like lemon and orange. But he did it because he thought that scurvy could be prevented with acids.
After years of research it was learned that scurvy is produced by ascorbic acid(vitamin c) deficiency and since we humans do not have the necessary machinery to synthesize it for ourselves, we need to consume it exogenously.