The first account of a blood transfusion is published, in the form of a letter from physician Richard Lower to chemist Robert Boyle, in Philosophical Transactions of the Royal Society

Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but modern medical practice commonly uses only components of the blood, such as red blood cells, plasma, platelets, and other clotting factors. White blood cells are transfused only in very rare circumstances, since granulocyte transfusion has limited applications. Whole blood has come back into use in the trauma setting.

Philosophical Transactions of the Royal Society is a scientific journal published by the Royal Society. In its earliest days, it was a private venture of the Royal Society's secretary. It was established in 1665, making it the second journal in the world exclusively devoted to science, after the Journal des sçavans, and therefore also the world's longest-running scientific journal. It became an official society publication in 1752. The use of the word philosophical in the title refers to natural philosophy, which was the equivalent of what would now be generally called science.

December 17 is the 351st day of the year in the Gregorian calendar; 14 days remain until the end of the year.