One of the most important craftsmen of Maryland was Frederick 

 A. Heisely (1759-1839). A native of Lancaster, Pennsylvania, 

 he served an apprenticeship there with John Hoff, the master clock- 

 maker, from 1777 to 1783. Heisely served in the Revolution. In 

 1783, presumably upon the completion of his apprenticeship, he 

 married Catherine HofF, the clockmaker's daughter. He moved to 

 Frederick, Maryland, where he established his own clockmaking 

 shop and where he specialized in making mathematical instruments. 

 A tower clock made in Frederick is in the collection of the U.S. 

 National Museum. Heisely returned to Lancaster to become 

 Hoff's partner, and worked with him until 1802. He then moved 

 his shop to Harrisburg and worked there until 1820. He moved 

 once more, this time to Pittsburgh where he advertised himself as 

 a "Clock, Watch and Instrument Maker," with a shop at No. 6 

 St. Clair Street. 



George Heisely (1789-1880), Frederick's son, who was born at 

 Frederick, Maryland, achieved note in his own right as a maker of 

 clocks and instruments. He worked at Second and Walnut 



Figure 28. — Brass surveying compass made by Goldsmith Chandlee for Laurence 

 Augustine Washington in about 1795. In the library at Mount Vernon. 

 Photo courtesy the Mount Vernon Ladies Association of the Union. 



57 



