PETER, professor of physic at Upsal, and physician extraordinary to the queen of Sweden, was born at Breslau in 1577. He studied Greek, Latin, Hebrew, Syriac, natural philosophy, anatomy, botany, and other sciences. Being told that a man could not distinguish himself in physic unless he understood Avicenna, he applied himself to the study of Arabic; and not only to read Avicenna, but also Mefue, Khafis, Abenzoar, Abukans, and Averroes. He visited Spain, Italy, England, and did not return home from his travels till after seven years. He was chosen by the magistrates of Breslau to have the direction of their college and of their schools. A fit of sickness having obliged him to resign that difficult employment, with which he was also much disgusted, he applied himself chiefly to the practice of physic, and went with his family into Prussia. Here he obtained the friendship and esteem of the chancellor Oxenstiern, whom he accompanied into Sweden; where he was made professor of physic in the university of Upsal, and physician to the queen. He died in 1642. It is said in his epitaph, that he understood 26 languages. He wrote many works; among which are, 1. Liber secundus Canonis Avicennae, typis Arabici, ex MSS. editus, et ad verbum in Latinum transtinctus, in folio. 2. De vero usu et abusu Medicinae. 3. Grammatica Arabica, folio. 4. Viva quatuor Evangelii rerum, ex antiquissimo codice MSS. Arabica eruta, in folio. 5. Note in Evangelium S. Mathei, ex collatione textuum Arabicorum, Syriacorum, Egyptianorum, Graecorum, et Latinorum, in folio, &c.

He ought not to be confounded with George Kerstenius, another learned physician and naturalist, who was born at Stettin, and died in 1662; and is also the author of several works.