グリニッジ天文台
In 1826 Dent submitted two chronometers, Nos. 54 and 55, for trial at Greenwich. This must indicate that he had made at least 55 chronometers by 1826. His submitting chronometers for trial brought him to the notice of the authorities at Royal Observatory, Greenwich. Indeed, in 1828 Dent was employed by Royal Observatory, Greenwich to examine and repair chronometers. His charges for repairing chronometers were as high as 25 guineas – an apparently exorbitant cost, but one that was nevertheless accepted.