An early 18th century French

An early 18th century French, Butterfield dial of canted oblong form with a sprung hinged gnomon with degrees of adjustment and a bird pointer the reverse engraved with twenty-four European cities and their degrees of latitude (40-51) signed "Le Maire Fils a Paris" and struck with a small discharge mark for Paris 1744-50 and contained in original fitted case, 2.9in (7.5cm) long.