Both in Salem and Bethlehem, Moravians continued to use music in their ceremonies. Instruments included organs and trombones, and voices were usually in choirs. Players generally played on rooftops for most any occasion, ensuring that they could be heard for great distances. A legend has arisen claiming that a group of Native American warriors approachied a Moravian settlement during the French and Indian War, but left after hearing a trombone choir because they believed it to be the voice of their Great Spirit. Moravians were devoted to missionary work, especially among African slaves and Native Americans; in 1763, they published a collection of hymns in the Delaware language.