The personage who typifies best the enlightened Slavonic Jew of the pre-Haskalah period is Tobias Cohn (1652-1729). He was the son and grandson of physicians, who practiced at Kamenetz-Podolsk and Byelsk, and after 1648 went to Metz. After their father's death, he and his older brother returned to Poland, whence Tobias, in turn, emigrated first to Italy and then to Turkey. In Adrianople he was physician-in-ordinary to five successive sultans. In the history of medicine he is remembered as the discoverer of the _plica polonica_, and as the publisher of a Materia Medica in three languages. To the student of Haskalah he is interesting, because he marks the close of the old and the beginning of the new era. Like the Maskilim of a century or two centuries later, he compiled and edited an encyclopedia in Hebrew, that "knowledge be increased among his coreligionists." His acquaintance with learned works in several ancient and modern languages of which he was master, enabled him to write his magnum opus, _Ma'aseh Tobiah_, with tolerable ease. This work is divided into eight parts, devoted respectively to theology, astronomy, pharmacy, hygiene, venereal diseases, botany, cosmography, and chemistry. It is illustrated with several plates, among them the picture of an astrolabe and one of the human body treated as a house. From the numerous editions through which it passed (Venice, 1707, 1715, 1728, 1769), we may conclude that it met with marked success.[37] * * * * * To understand the _raison d'Etre_ of the Haskalah movement, it may not be superfluous to cast a glance at the inner social and religious life of the Slavonic Jews during pre-Haskalah times. The labors of the farmer are crowned with success only when nature lends him a helping hand. His soil must be fertile, and blessed with frequent showers. Nor would the Maskilim have accomplished their aim, had the material they found at hand been different from what it was. The Jews in the land of the Slavonians were fortunate in being regarded as aliens in a country which, as we have seen, they inhabited long before those who claimed to be its possessors by divine right of conquest. If their position was precarious, their sufferings were those of a conquered nation. As the whim and fancy of the reigning prince, knyaz, varied, they were induced one day to settle in the country by the offer of the most flattering privileges, and the next day they were expelled, only to be requested to return again. Now their synagogues and cemeteries were exempt from taxation, now an additional poll-tax or land-tax was levied on every Jew (serebshizna); one day they were allowed to live unhampered by restrictions, then they were prohibited to wear certain garments and ornaments, and commanded to use yellow caps and kerchiefs to distinguish them from the Gentiles (1566).