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, Italy 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.