Zinn was a student of Albrecht von Haller. In 1753 he was appointed Professor of Medicine at Göttingen, and Director of the Botanical Garden. He published a catalogue of the plants in the Garden, which was praised by Linnæus, who named the Zinnia plant in his honour. Descriptio anatomica oculi humani was a fundamental work on the anatomy of the eye, and the first complete work of ophthalmology. Zinn describes the fibræ radiatæ, and shows that the number of fibre bundles in the optic nerve is constant, and continuous with those of the retina. His name is connected with several of the fine structures of the eye, including the central artery of Zinn, the circulet of Zinn, and the zonule of Zinn. There are twenty-eight illustrations on seven plates, engraved by Joel Paul Kaltenhofer.