Portable Drum Clock
Portable timekeepers could not be produced until clockmakers were able to reduce the size of the mechanism, and the first successful attempt is believed to have been in Italy around 1500. Throughout the sixteenth century, portable clocks, often in the shape of small drums, were made elsewhere in Europe, notably Augsburg, Germany, which became a leading producer of clocks during the Renaissance. This early example has small touch pins at each hour to allow the user to tell time at night by simply feeling the position of the hour hand. Over the next fifty years, the drum clock evolved into the more convenient pendant watch.
Source: Vignon, Charlotte. The Frick Collection Decorative Arts Handbook. New York: The Frick Collection/Scala, 2015.