Blood type theory is one of the fundamental bases for surgical operations. Only with this theory can safe transfusions occur, allowing many surgical procedures to proceed.
Li Ang took out the tools he had prepared in advance from the medical kit he carried with him—a large number of syringes, glass slides, glass test tubes, and the human-powered centrifuge he had previously used at the Duke Yan Mansion.
Li Ang drew a small amount of blood from himself, Yang Yu, Li Wei, Zhang Yuyan, and a few other classmates from the Academic Palace and placed it into glass test tubes, attaching labels.
Then, taking a small amount of fresh blood from each test tube, he combined them in pairs, dropping them onto glass slides for mutual mixing.
Under the watchful eyes of the Academic Palace Doctors and students, some blood samples began to clump together, while others merged smoothly.
