An unusual late 17th Century yew wood Horary Quadrant, stamped with initials and dated N H 1694 (initials may be those of the maker or owner), the scale marked with latitude 52° 15=f, laid out on semicircles that fold together by brass hinges, two hooks hold the leaves closed for the pocket, the reverse with twin pegs (for bar, now missing to provide rigidity), the obverse with hour lines that occupy 60 degrees along the altitude scale, within a heart-shaped figure, lines for a single altitude, Cambridge (modern figure 52° 13=f), month scale, missing plumb line and pin, with old style perpetual calendar the rows of stamped numbers labelled Mo months, (where 1=March) Dai day, DL Dominical Letter, LY Leap year, Epa Epact, - diameter 5¾in. (14.7cm.)

Details

An unusual late 17th Century yew wood Horary Quadrant, stamped with initials and dated N H 1694 (initials may be those of the maker or owner), the scale marked with latitude 52° 15=f, laid out on semicircles that fold together by brass hinges, two hooks hold the leaves closed for the pocket, the reverse with twin pegs (for bar, now missing to provide rigidity), the obverse with hour lines that occupy 60 degrees along the altitude scale, within a heart-shaped figure, lines for a single altitude, Cambridge (modern figure 52° 13=f), month scale, missing plumb line and pin, with old style perpetual calendar the rows of stamped numbers labelled Mo months, (where 1=March) Dai day, DL Dominical Letter, LY Leap year, Epa Epact, - diameter 5¾in. (14.7cm.)

Provenance

Formerly in the possession of Lt.Cdr Frederick D.Hart

Lot Essay

The quadrant is to the design of Edmund Gunter published in 1623, but with the omission of the lines of the Sun's azimuth. The folding design has not been found before with this type of instrument. The leap years are marked from 1680-1704. This may indicate that the instrument was made nearer to 1680 than the date stamped on it; however the number punches are identical. The use of the outline of a heart is a design feature found on a few horary quadrants made during the seventeenth century. Some are signed J.B. for John Browne (fl.c. 1644-1697). Others are engraved Londini fecit, but with no name or initials, and another is not inscribed, both implying a product made for retailers. Examples are in the British Museum, National Maritime Museum, and Science Museum

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