Ma'aseh Tuviyyah, Tobias Cohn, Venice: Bragadin, 1707

164 leaves (8 x 6 in.; 205x 152mm). foliation:(6), 1-90 (2), 93-130 (1), 132-158. Sectional title pages with architectural borders; frontispiece with portrait; numerous illustrations. Title page and first few leaves remargined, strengthened at gutter and with repairs to corners; Usual light soil and stain, heavier on title page and first few leaves. Owners' notes on title page. Modern quarter morocco over marbled boards, corners worn; label residue. Spine with stamped titles.

Vinograd, Venice 1572; Zedner, p. 758; Steinschneider 7305

During the 17th century the only Jews in Central and Eastern Europe who had an opportunity for advanced secular education were those who trained as physicians. Tobias ben Moses Cohn (1652-1729) succeeded in 1678, with the intervention of the great elector, Frederick William of Brandenburg, in gaining admission to the University of Frankfort on the Oder. When the Lutheran faculty refused to admit Jewish students to doctoral examinations, he was unable to obtain his degree and went to Padua. He practiced in Poland and in Turkey where he became physician to five successive sultans in Constantinople, before retiring to a life of Torah study in Jerusalem.

Ma'aseh Tuviyyah, Cohn's magnum opus, is an encyclopedia dealing with theology, astronomy, cosmography, geography and botany, with medicine taking up about half of the entire work. The author describes the system of Copernicus but rejects it on religious grounds. On the other hand, he enthusiastically endorses William Harvey's newly discovered system of blood circulation. He stresses the chemical aspect of stomach diseases, in contrast to the then still prevalent system of Galen. He also deals at some length with a disease of the hair then common in Poland, plica polonica, and his theories relating to infant care and pediatrics which were advanced by the standards of his era.

Although Cohn adheres to a traditional model of medicine, he is fully conscious of new trends, especially in surgery and in chemistry. He applies exact measurements in his scientific work, especially in thermometry. One of Cohn's innovations is the comparison of the human body to a house. The head was the roof, the eyes the windows, and the mouth, the doorway; the chest was the upper story, the intestines were the middle story, the lungs were water tanks and the legs, foundations. He subscribed to many popularly common remedies such laxatives, emetics, cupping glasses, and bleeding, but he argued forcefully against many superstitions.

Profusely illustrated, Ma'aseh Tuviyyah is also rich in historical references. For example, Cohn describes the lingering effects of Sabbatianism; in a seeming reference to his own brother-in-law, Rabbi Jair Hayyim Bacharach, he writes "Even many of the sages of the land and the great renowned rabbis, whom I would not want to mention publicly, accepted him [Sabbetai Zevi] as master and king over them." A full page copper-plate portrait of the author appears on the verso of the title page.