The main source of published commentary on the Castle Rushen clock is Ernest Edwardes’ article The Old Clock at Castle Rushen (Horological Journal, July 1956). Passing mention of the clock also appears in the Journal of the Manx Museum (Vol. 1, p. 100). A very brief note on the clock appears in a recent edition of the Horological Journal.
There would not appear to be any documentary evidence to support the assertion of any connection to Queen Elizabeth the First, nor to the year 1597. A painting in the Manx National Art Collection, Castle Rushen from the Market Place by Moses Griffith, dated 1774, shows the lozenge dial as today, with a sundial that was “perhaps removed when the dial was restored in the later part of the last century”.
View of Castle Rushen in ye Ille of Mann on the South-West Side, a drawing attributed to Charles Frederick and bearing the IA monogram of James, Duke of Atholl with the date 1736, also shows the lozenge clock face, again surmounted by a sundial.
Castle Rushen as it appears on the South East side, drawn by Daniel King c. 1650, corresponds quite closely in point of view to the 1736 drawing, but shows no sundial and no clock face.
None of the early drawings show the tower surmounted by a campanile.
An inventory of the household effects of the 7th Earl of Derby from 1651 suggests that the clock was in its current location at that time.
A turret clock such as this would originally have had a verge and foliot escapement. Many were converted to pendulum escapement as here, from the second half of the seventeenth century. The early clock would not have had a face, and it is tempting to associate the conversion of the escapement with the provision of a clock face sometime between 1650 and 1736. Close inspection of the methods of manufacture and the materials of construction reinforce the opinion of E.L. Edwardes, adopted by subsequent commentators that the clock was made in the 16th century for this location.