English, c. 1730-1740, black sharkskin covered case with instruments in gree velvet lined fitted interior, instruments include fine proportional dividers with locking cross-bar and ropework knurled knobs, engraved 'T Heath London', large compass with locking interchangable ink, pencil and divider ends, dividers with sprung fine adjustment by wingnut, a steel point tracer (?) that unscrews to become a pricker (thread worn), ink drawing pen, pencil and original combination adjustment tool/file/penknife (tool fits compass joint),the green silk lid interior lifts to reveal the fine brass sector with cross bar, and empty compartment probably for a parellel ruler, case 18.6cm across