Although the tax records for 1796 described Dring as an "Optician" he was also a clockmaker and maker of scientific instruments. At least three of his tall-case clocks have survived, and a stick type of barometer which he made for Edward and Hannah Hicks in 1796. The instrument is now in the collection of the Chester County Historical Society. It measures 39 inches in height, and is signed on the thermometer dial THOMAS DRING/West Chester. This instrument (fig. 14) is one of the very rare barometers produced in America in the 18th century. Another craftsman who emigrated from England was Robert Clark, who opened a shop at 5-1/2 Church Street in Charleston, South Carolina, in 1785. In that year he announced himself as a Math., Optical and Philosophical Instruments maker and Clockmaker from London ... As the Advertiser has lately had an opportunity of working and receiving instruction under the first masters in the above branches in Great Britain, flatters himself that he shall give satisfaction to those who may be pleased to favor him with their orders ... for Surveyors compasses, Quadrants, Telescopes, Microscopes, Spirit Levels, etc.[21] W. Fosbrook was another craftsman originally from London. He was a cutler and maker of surgical instruments, with a shop in Beekman's Slip in New York City in 1786 or earlier. He specialized in leg irons and rupture trusses, and he made instruments and files for setting the teeth as well as standard items for surgeons.[22] [Illustration: Figure 14.--Barometer made in 1796 by Thomas Dring of West Chester, Pa., for Edward and Hannah Hicks. Photo courtesy the Chester County Historical Society.] Several immigrant instrument makers established themselves in Philadelphia during the same period. John Denegan (or Donegan), stated to have been "late from Italy," moved his shop in March 1787 to the corner of Race and Fourth Streets at "the sign of the Seven Stars".[23] There he made barometers and thermometers as well as glasses for philosophical experiments. It seems too much of a coincidence that in October 1787 an instrument maker named Joseph Donegany established a shop at 54 Smith Street in New York City,[24] where--according to an advertisement in the October 17, 1787, issue of _The New York Daily Advertiser_--he made "thermometers, barometers and sold hydrostatic Bubbles and hygrometers for proving spirits, and also ... glasses for experimental purposes." It is probable that Denegan and Donegany were one and the same; since Denegan was stated to have been of Italian origin, the name may originally have been "De Negani."