Notes:
A Butterfield type sundial and compass by Zvolochy Samoliovy with its leather case sold at auction for £11,000.
Similar exampleby the same maker
Michael Butterfield (1635-1724) was a British clockmaker who worked in Paris in the late 17th and early 18th century. He was primarily known for producing sundials for use by Grand Tour travellers, enabling them to determine the time in the towns they visited. He opened a shop selling precision instruments in 1677 in rue Neuve-des-Fosses, in Saint Germain, where his sundial became fashionable. From this location he sold all types of sundials, dominating the market with his small travelling sundial featuring an adjustable bird gnonom and three chapter rings. This type of dial became the height of fashion and became known as the 'Butterfield Dial'. In addition, he worked at the Royal Court and was appointed engineer by the King Louis XIV.
They were used from the late 17th century onwards and could be more accurate than clocks
Similar examples can be found in the British Maritime Museum, V&A and the British Museum.
A Butterfield dial is a portable horizontal sundial designed to be folded flat and used in latitudes between 35° and 60°. It was named after the English gnomonist Michael Butterfield, who was active in Paris around 1690.
The dials were constructed with a hinged gnomon, whose angle could be adjusted for the latitude; the latitude was indicated by the beak of a bird. The gnomon was held in place by a rivet which was displayed by the birds eye, and thumbscrew.
The dial plate had three chapter rings for 44°, 48° and 52° which would be sufficiently accurate to be used between 35° and 60° (roughly between Gibraltar to the Shetland Isles). There would also be a compass and a plumb bob.[1
