Fox dip and intensity apparatus by George
circa 1840
Dip circle by Nairne and Blunt
1775
Dip circle and part
Dip circle
1775
Kew pattern dip circle by Henry Barrow
1851-1864
Dip circle
1904
Kew pattern dip circle by Dover, c.1870
1870
Dip circle by Dover
1891