A Charles Essex & Co. Pocket Sundial Compass or Pantochronometer, dating from c.1825, and signed on the dial 'C. Essex & Co, London'. Charles Essex is known to have been in business as an optician in Clerkenwell, London between 1824 and 1828. This sundial compass has a wooden case with a domed push-fit lid, a paper compass card with a jewelled pivot, and a brass gnomon. The interior of the wooden case is painted red, and the compass card is protected by a domed glass cover.
This type of sundial compass - a floating sundial on a compass card - is also known as a Pantochronometer or 'Magnetic Dial'. The system was already in use in the 18th century, but the term Pantochronometer was coined in the 1820's by Charles Essex, an optician whose shop was at 28 Gloucester Street, Clerkenwell, London. He is mentioned in an article published in The London Literary Gazette on 17th December 1825, in which the Pantochronometer is decribed as 'one of those clever little philosophical instruments, the invention of which does credit to the ingenuity of modern science. It has been produced by Mr Charles Essex and is at once a curious and useful thing. In a box, about the size of a small snuff-box, are combined the machinery of a compass, sun-dial, and universal time-dial; and a compass card, a gnomon, and an indexed border, form the whole of the simple process. It is a desirable power to be able to pull this "dial from your poke" and ascertain at once what o'clock it is, the situation of the spot where you are, and the way you ought to go. We must say it is a very neat and ingenious production'. An advertisment in the same issue stated that 'Its novelty, elegance, construction, and scientific utility, render it peculiarly suitable for a New Year's gift, or Christmas present. Sold retail at Opticians, Stationers &c, and wholesale by Charles Essex & Co, 28 Gloucester Street, Clerkenwell, London'.
Various other types of wooden domed-glass sundial compasses were produced in England in the first half of the 19th century - including the 'Magnetic Sundial' made by Samuel Porter in 1824. Elliot Brothers also produced a range of high quality brass-cased pocket sundials in the 1850s.
(Thanks to compassmuseum.com for the information about Charles Essex. Further details of sundial compass design, and the history of pocket sundial compasses, can be found at the excellent compassmuseum.com website, page: http://www.compassmuseum.com/sundials/sundials.htm)
***Please note: the small white areas on the glass in the photographs are just reflections - there are no white marks on the glass. It is almost impossible to photograph a high-domed glass like this without reflections***
Condition
In excellent condition, full working order and finds North well. The wooden case is in very good condition, with no damage, just minor signs of wear and use. The lid fits very well. The original domed glass is in very good condition. The compass card and gnomon are in very good condition.
Dimensions:
wooden case: 60mm diameter x 35mm height
compass card: 40mm diameter
