"Silver Sundial By Butterfield"
Horizontal pocket dial in silver (discharge hallmark) octagonal in shape, folding style "a l'oiseau" adjustable according to the latitude. Signature of Butterfield the inventor of this type of dial. Four scales for reading the time, alternately in Arabic and Roman numerals. The latitude of 26 cities is specified under the plate plus 7 under the compass bowl. L ointment 7.8 cm, width 6.6. Louis XIV period. 
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