| Signature | Maker | Instruments | Comments | Location | References | 
| DOVER, JOHN | England, 1824-81, NIM PHIM | Inclinometer = USNM; Magnetometer = USNM; Dip Needle = Royal Greenwich Observatory, Cambridge. | father of A.W. Dover; apprenticed to Thomas Charles Robinson; balance maker; exhibited a balance at the Great Exhibition of 1851, in London. | 14 Little Street, London; Charlton, Kent. | Multhauf and Good; Bryden 8; G.L'E. Turner 24; RSW. | 
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