Cohn was familiar with ten languages – Hebrew, German, Polish, Italian, French, Spanish, Turkish, Latin, Greek, and Arabic. This great linguistic knowledge made it possible for him to write his ''
Ma'aseh Toviyyah'' (Work of Tobias), published in Venice in 1707, and reprinted there in 1715, 1728, 1769, and 1850. The work is encyclopedic, and is divided into eight parts: (1) theology; (2) astronomy; (3) medicine; (4) hygiene; (5) syphilitic maladies; (6) botany; (7) cosmography; and (8) an essay on the four elements. The most important is the third part, which contains an illustration showing a human body and a house side by side and comparing the members of the former to the parts of the latter (see illustration). In part 2 are found an
astrolabe and illustrations of astronomical and mathematical instruments. Inserted between parts 6 and 7 is Turkish-Latin-Spanish dictionary; and prefixed to the work is a poem by
Solomon Conegliano. Cohn's medical knowledge and experiences seem to have been of considerable importance. He gave, from his own observations, the first description of the "plica polonica," as well as many local symptoms and newly discovered medicinal herbs. He also published in three languages a list of remedies. ==References==