A 17th century Double Dial for the Pocket Click on any image for a larger view.

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REMARKABLE DOUBLE ANALEMMATIC HORIZONTAL POCKET SUNDIAL, French, c. second half 17th century, the eight-sided all-brass dial plate measuring 2" x 2-11/16" (5 x 7 cm). The plate is engraved with a circular chapter ring divided every hour from 4am to 8pm, with a circular Zodiacal calendar scale, and with a semi-elliptical hour scale divided again from 4am to 8pm. The circular chapter is engraved with radial hour lines, and set with a hinged gnomon; the Zodiacal circle is crossed by a straight meridian line of 14 holes for inserting a vertical pin gnomon at the appropriate date position; and the field within the elliptical chapter is filled with engraved floral petals aligned with the hour lines. There is also a small inset glazed magnetic compass with good early needle and directionals labeled "Nor, Sud, Est, Oest," and bearing an engraved fleur-de-lys north mark. The underside is plain, with two feet, compass box, and gnomon spring. Condition is fine with a separate brass pin gnomon and the original pebbled leather covered wood case lined in white and reddish satin.

The double analemmatic dial was described by J.L. Sieur de Vaulezard in 1640. Its big advantage was its independence of knowledge of magnetic north, and thus independence of the magnetic compass. Knowing the date, one places the vertical pin gnomon in the appropriate position, sets the dial on a horizontal surface, and rotates it until both sundials read the same time, which is the correct apparent solar time. This instrument is also equipped with a small compass, for convenience and in fact as a means for determining the magnetic declination, the local difference between astronomical north and magnetic north. The double dial is particularly interesting, and has been constructed in various forms (see for example Thomas Tuttell's version, Tesseract Cat. 50 Item 20). The present miniature variant, with its insertable pin gnomon, and with its pocket case reminiscent of those of Butterfield-type dials, is otherwise unknown to us. (9136) $9500.


Masonic Sundial with Descriptive Gnomon Click on any image for a larger view.

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SCOTTISH HORIZONTAL SUNDIAL WITH "LATITUDINAL" GNOMON, 1821, signed "Pat. Robertson, 1821." The sundial is constructed with a sturdy slate base 13-3/4" (35 cm) square and 7/8" (2.2 cm) thick, mounted with 4-3/4" tall pierced brass gnomon. The base is pierced with four mounting holes, and is engraved with the signature and date, and with the circular chapter ring divided every 5 minutes of time from 4am to 8pm. Each hour is labeled with a fascinating system of simplified Roman numeral shapes: "ones" are straight vertical lines, "fives" are shorter slightly-backwards-leaning straight lines, and "tens" are longer steeply-backwards-leaning straight lines, all with slight seraphs. Measuring the gnomon angle, we find it is designed for latitude approximately 56°. The brass has wonderful piercing, showing a compass and square, presumably as Masonic symbols, and with the latitude given in pierced numerals (57.°5). Condition is fine noting some surface wear and chips to the stone, the brass with old brown and green patina.

Robertson is a common Scottish name, and Bryden lists two instrument makers and/or sellers by this name, including one Patrick Robertson recorded in Edinburgh in 1778. The latitude is north of even Aberdeen (57°.15) and coincides with that of Inverness in the Scottish Highlands (just downstream from Loch Ness, and very near the site of the Battle of Culloden), and that of Peterhead in easternmost mainland Scotland. An interesting Northern dial. (9126) $3950.


17th century English Silver Click on any image for a larger view.

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HOROLOGICAL COMPENDIUM IN SILVER, probably English, c. 1663, standing 3-3/16" (8 cm) tall when assembled. Constructed of silver (with some internal fittings of heavy silver plated brass), the compendium disassembles somewhat as a "penner," into five components: (1) a tapered eight-sided body very finely engraved with two columns of "Dayes" from 1 to 31, and twelve columns of repeating sequential day letters "a" through "g"," one column for each "31-day" month of the year. Three internal holes in the body could store very small materials (quill, cutter, wax, etc.); (2) removable cap engraved with the year from 63 to 78, each with corresponding one or two day letters; (3) miniature horizontal sundial with folding gnomon inclined for approx-imately 43° latitude, 5/8" (16 mm) diameter chapter ring (4 am - 8 pm, Northern hemisphere), and glazed compass with tiny arrow shaped needle with shaped brass hub. The base of the sundial, which faces upward when the compendium is assembled, is engraved with a lovely seven-pointed rose; (4) octagonal screw-on cap which could hold a small wick, etc., and which serves as a foot for the sundial; (5) octagonal screw-on base which could hold, for example, a candle. Thus we have a pocket calendrical / horological / compendium which could carry small writing / letter sealing material. Condition is fine, noting several small dents, some wear around the base of the body, and wear to the threads.

As to origin, the language is clearly English ("Dayes"); the numeral shapes do have an English look, except for the seraphs on the "1's" and the accentuated tail on some of the "7's." The latter is found, interestingly, on some of Henry Sutton's engraving (see, e.g., Gunther, 1936). The measured sundial latitude, if accurate, is quite interesting, suggesting manufacture for the Mediterranean, or even for the early American colonies (Boston, Albany,...). As to date, the tables give a ready clue, as they present a perpetual calendar for the days of the week. Starting with "a" for 1 January, there is a continuous recurring cycle through the seven letters for the full year. Meanwhile the table on the cap gives the Dominical letters for years 63 through 78. Thus "63" is "d," making 4 January a Sunday, in complete agreement with the Julian calendar in effect in England in 1663. The Dominical letter for 1763, by contrast, and of course under the adopted Gregorian system, is in fact "b." We find further complete correspondence through the years 1663 - 1678, so this perpetual calendar compendium must have been constructed c. 1663, for use over the next 15 years. A remarkable device, of high quality. (7164) $9500.


Rare 17th century Diptych Sundial from Rome Click on any image for a larger view.

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UNUSUAL FRUITWOOD DIPTYCH DIAL, Italian, c. 17th century. Measuring 2-1/2" x 3-1/2" x 7/8" (6.6 x 8.8 x 2.2 cm) closed, the dial is handshaped of lovely fruitwood with fittings of brass and horn, and inset glazed compass with shaped needle and paper marked with magnetic declination. The angle of the lid is adjustable in latitude against a calibrated and notched hinged brass arm engaged by brass slider above. The wood and horn have decorative straight and crenelated outlining, circles, star punches, and rose carvings. Numerals are punched, and the brass has hand cut wiggle-work patterns. Surface Ia has a polar dial divided every half hour for twice twelve hours, with brass hub to hold a vertical pin gnomon which would stow in a lidded compartment in the base. This dial is completed by a Latin motto "Si Solo deficit nemo me respicit," (If the sun withdraws, no one will pay attention to me). Ib has a string gnomon vertical dial divided 6 am to 6 pm, with black lines and red numerals, and marked for the latitude "GR. 42," plus a vertical pin gnomon dial for Italian hours (13 - 23) and stamped with Zodiacal signs. IIa bears again the latitude mark, with a horizontal pin gnomon dial again for Italian hours (10 - 23). IIb is inked with a large table in manuscript, including approximately 20 Italian cities and their latitudes.

Workmanship is somewhat primitive and the condition is rather rough, with insect losses to the horn fittings, caus-ing hinge failure, and water losses to the manuscript table on the base. Nevertheless it is a most interesting diptych dial, rare as an Italian example, doubly rare in fruitwood, and unusual for its features especially the slide clamp for latitude setting. We find very few recorded Italian diptych dials, noting in particular the three in the Harvard collection recorded by Lloyd (compared with the 46 German and 32 French examples). The latitude (42°) is that of Rome. (7144) $3950.


Finding Geographic North by the Sun Click on any image for a larger view.

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A MIDDAY-LINE RECKONER, Austrian, c.1900, signed "Neuhöfer & Sohn in Wien." Made of heavy brass, finely machined and standing 4-1/4" (11 cm) high, this unusual form of noon mark has a pinhole on top and a vertical scribe line passing through it and down to the base. In use one can plot, on a leveled plane table, the meridian sun's projection through the pinhole, giving the direction to geographic North. Placing a trough compass along this line immediately gives the magnetic declination, i.e., the local deviation between magnetic North and geographic North. An unusual device, reminiscent of the monumental noon mark projections in cathedrals, in very fine condition complete with instructions and card box. (9146) $750.


Safety in the Phrygian Bonnet Click on any image for a larger view.

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A REVOLUTIONARY SUNDIAL, French, 18th century, unsigned, of the "Butterfield" type. The eight-sided brass dial measures 2-1/2" x 3" (6 x 8 cm), with folding gnomon adjustable from 40° to 60° North latitude against bird-form support, and inset glazed compass. The upper surface is engraved with four chapter rings for different latitudes, and most distinctive cross-hatched decoration. The underside has a gazetteer of 17 cities and their latitudes, the spring plate also with cross-hatching. The gnomon carries unusual leafy vine decoration. Condition is fine noting the tiny interior tip of the gnomon is broken off, and the glass and needle are probably replacements. In all respects the decoration is special -- this dial was not made by any of the standard makers of the period: Butterfield, Bion, Macquart, Chapotot, etc. But it is the inset compass that carries the most remarkable history. It is divided with an eight point rose labeled with directions, and a magnetic variation scale from 30° E to 30° W. The North point shows traces of an effaced fleur-de-lys (traditionally the symbol of the monarchy in France), re-engraved with a bold Phrygian bonnet (the symbol of liberty adopted during the Revolution, based on the hat worn by the Phrygians of antiquity, in Asia Minor). This directional was obviously re-engraved in the last decade of the 18th century, when it became very unhealthy to be caught carrying a royal fleur-de-lys! (8130) $2950.


Incense Tells the Time, in 18th-century Japan Click on any image for a larger view.

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JAPANESE "JOKOBAN" INCENSE CLOCK, Edo period, c. 18th century. This handsome timekeeper is constructed of a beautifully grained and stained light weight wood (probably paulownia or cryptomeria) and measures 11-3/8" (29 cm) square by 15-5/8" (40 cm) tall. The lower section has attractive lozenge-shaped cutouts around the base, and a large matching drawer for tools and accessories. The upper section has a square wooden burning "pan" surmounted by an open wooden latticework cover formed as an 8 x 8 grid; the whole upper section is free to rotate, and lifts off easily. Four wooden tools are included: template, tamper, spatula, and five-tined comb. Condition is fine throughout, noting a couple of minor age cracks and slight heat damage to the pan and cover.

The jokoban was used in community life as well as in Buddhist temples, to measure extended spans of time (see Bedini, The Trail of Time, 1994, for comprehensive, lucid discussion of East Asian time measurement by incense burning). After covering the bottom of the pan with a uniform layer of fine wood ashes, and tamping this down, one impressed the template into the ash, then filled the pattern of trails with very slow-burning incense. The template is a "maze" of five long interconnected parallel lines. This was impressed four times, swiveling the pan by 90° each time, resulting in a kind of swastika design for the incense trail. After the incense was ignited at the starting point, the time was determined by the position of the point of burning along the trail; total burn time could be twenty hours. The latticework cover passes heat and smoke, and prevents breezes from accelerating the combustion. The swastika pattern, commonly found on Buddhist inscriptions, represents "many" or "longevity" or "infinity," and "is ordinarily accepted as the accumulation of lucky signs possessing 10,000 virtues" (Bedini).

A fine example of this unusual horological device. (9153) $5500.


A Most Rare Compass/Sundial Click on any image for a larger view.

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MAGNETIC AZIMUTH SUNDIAL, French, late 19th century, signed "J. Decoudun." The 1-1/8" (3 cm) diameter glazed case is made of plated brass and mounted with pendant ring. It contains a fixed brass arc with compass directionals, and a floating compass card printed with hours from 6am to 6pm and set with stone pivot. Condition is very fine noting some darkening to the silvered arc.

In use one aligns the case with the sun, and reads the time from the calibrations on the floating card.

The maker is recorded by Marcelin for a sundial -- probably this one -- in a 1986 Paris auction. But Decoudun is known for his 1888 extinction exposure meter, and for a new form of pneumatic hydrometer. He also advertised -- from his 8 rue de Saint-Quentin, Paris, address -- the availability of a safe oil-burning bed reading lamp. This is the only example of his magnetic sundial we have seen. (9143) $495.


Elegant 1789 Dial by a Thoughtful Craftsman Click on any image for a larger view.

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UNUSUAL HORIZONTAL DIAL, English, 1789, signed "Onions, 1789, Lat. 51°30'." The 3" x 4" (8 x 10 cm) brass dial is set into a tabernacle-shaped fruitwood carrying case, complete with early handwritten equation of time table. The brass dial itself is beautifully executed, the folding gnomon pierced and engraved with floral design, the chapter ring divided every five minutes, the inset compass surrounded by engraved vines and flowers, the glazed compass itself with engraved brass compass rose and finely cut needle. To the west of the fleur-de-lys North point is an engraved "V" and "27," indication of the point of magnetic variation. (In fact, consulting a plot of variation vs. time and place, we find, for London, the declination in 1780 was 23° West and heading further west at about 0.15 degrees per year ‹ as it had been doing for the previous 200 years. Thus Onions, in 1789, could have anticipated a variation of 27° about 20 years later, and constructed a dial made to last. In fact, the actual variation slowed down and, reaching a peak about 1810, then reversed direction, and now approaches 0° in London. It never made it close to 27°!) Condition of the dial is very fine, noting a crack and water (?) damage to the wood base. The maker, presumably Peter Onions, is listed in Loomis as a clockmaker working in Brosley c.1760. He gave his own distinctive, rather elegant design to the dial and its decoration. The overall shape, in fact, mimics that of a standing clock! Most unusual. (7206) $4950.





Time, Temperature, and Direction Click on any image for a larger view.

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TRAVELLER'S COMPENDIUM WITH SUNDIAL, English, c.1840, signed "T. Staight, London." The 2-3/8" (6 cm) diameter turned ivory disk supports a circular mercury thermometer with Fahrenheit and Reamur scales, and a fine floating gnomon compass / sundial, glazed with a carved ivory surround. Condition is very fine but for a crack in the glass; it is complete with the original domed wood case bound in red Morocco leather. The maker, Thomas Staight, gained his freedom in the fanmaker's guild in 1828, and worked 1829-1860 specializing in barometers, thermometers, and ivory turnings. Works by him are rare -- we note one essentially identical compendium illustrated by Higton (2001). (9175) $1250.


Early English Dialling Click on any image for a larger view.

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FOUR-SUNDIAL COMPENDIUM, English, c. second half 17th century, signed "Phil. Edwards." Constructed of fine boxwood, this unusual diptych compendium measures 4" x 4-1/4" x 1" (10 x 11 x 2.5 cm) closed. Surface Ia is divided, every quarter hour, with a twice-12 hour scale full circle, and would work in summer, when the sun is above the plane of the equator, with a central straight pin as gnomon. Surface Ib is again divided, half-circle, from 6am to 6pm, functioning similarly in winter. The pin gnomon must be aligned parallel to the earth¹s polar axis, and thus inclined to the horizontal by the user¹s latitude; this inclination is set by a fine brass strut divided every 2° from 0° to 90°, and with central slot engaging a pin. Another dial is inscribed on Ib, this a vertical dial for a fixed latitude (approximately 50° N), divided 6am to 6pm, and maintained vertical by the strut engaging a second pin. The string gnomon for this dial would run from a brass fitting on the base to a hole on top. IIa uses the same gnomon for its horizontal 4 am - 8pm dial, which surrounds the large inset glazed compass required for orienting the sundial exactly towards geographic north. The compass has a fine arrowhead needle, a circumferential scale of degrees, and an interesting printed paper rose with its own degree scale plus 32-point rose with 32 labeled directionals and subdivided to 256 points of the compass. Surface IIb is blank. Condition is very fine except the boxwood badly warped and with hairline cracks. The warping is stable and the instrument fully functional.

The maker Phil(ip) Edwards was a fine craftsman (except for his choice of the pieces of boxwood!) but is not listed in the standard references. Clifton records a number of Edwards's as instrument makers, but the only ones of the right time period are Richard (working 1660 -1667) and his wife Mary (working 1668), noting they had as apprentice one John Yarwell! Here the numeral and letter shapes are rather specific to English work of the second half 17th century, and the lack of any indication of magnetic declination on the compass rose suggests it was made c. 1660 - 65, when the declination in London went through zero. (9205) $5500.


Eighteenth Century Time-Telling Click on any image for a larger view.

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GOOD POCKET COMPASS / SUNDIAL, English, c. second quarter 18th century, the turned brass case and screw-on cover 3-3/8" (8.5 cm) in diameter. The glazed compass is mounted with a beautifully designed and engraved paper rose incorporating 16 directionals, circumferential degree scale, running leaf tip design, and exquisite floral patterns. An identical paper is applied in the lid. The original shaped iron needle has an eight-sided pyramidal brass hub. Atop the glass is a fine brass chapter ring (divided every five minutes from 4am to 8pm) also with leaf tip engraving, and with folding gnomon designed for approximately 51° North latitude (consistent with London design). Condition is fine noting three later small holes in the base, and the case exterior darkening slightly. A very finely crafted instrument. (9121) $975.


Superb Craftsmanship with a Camouflaged Date Click on any image for a larger view.

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  SOLNHOFER STONE SUNDIAL WITH DATE HIDDEN IN A CHRONOGRAM, German, 1723, bearing arms labeled "GA ZN," the latitude (47°33'), and a Latin motto which conceals the date (1723). The 6-3/4" x 8" (17 x 20 cm) block of very finely grained Solnhofer stone is acid-etched with a fine projection of chapter ring (divided every quarter hour from 4 am to 8 pm) and Zodiacal calendar. It is set with a shaped brass gnomon with oculus for the calendar scale, and is mounted in a dovetailed softwood frame. Condition is very fine throughout, noting an old scratch and some quite small edge chips. Solnhofer stone, found in southern Germany, is particularly suited for fine etching, and often served as lithographer's stone. The specific latitude agrees with almost the southern tip of Germany (e.g., Lindau, Bregenz), and parts of Austria. The date is revealed by adding all of the capitalized letters (taken as Roman numerals) in the motto, a technique used by Renaissance scholars in a period of classical revivalism. A very fine example, deserving of further research into the elaborate heraldic arms with its bishop's(?) miter. (8149) $4950.



Henry Sutton's Design Click on any image for a larger view.

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HENRY SUTTON'S FORM OF MAGNETIC AZIMUTH DIALLING COMPASS, English, c. third quarter 17th century, unsigned. Set in an eight-sided wood mount, 4-3/4" (12 cm) across, the compass has a fine printed card, a most elegantly shaped needle, and a circumferential wooden degree circle. The card has degree scales, twice-12 hour scales, calendar scale, solar declination scale, and 32-point rose. Condition is good noting the wood housing is cut on one side (where it may have attached to a plane table), the glass replaced. A similar dial face is shown on Henry Sutton's 1654 trade card (see Derek Price in Singer et al., 1957), along with instructions to direct the south side of the compass card toward the sun, and read the time where the north end of the compass needle (in summer; south end in winter) crosses the hour lines along the proper parallel of solar declination (as read from the central circular table). A very rare dialling compass. The Museum of the History of Science in Oxford holds a boxwood diptych sundial mounted with a similar compass card, and owns a variant slightly earlier unmounted card signed "Henry Sutton Londini fecit *1653.*" The card design has been discussed in detail by Jim Bennett (Sphaera issue 10). (8138) $4800.


International Time Conversion Click on any image for a larger view.

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THE PANOROGRAPHE OF ENGINEER VALLE, Italian for the French market, last quarter 19th century, consisting of a heavy printed card 3-3/8" x 4-1/2" (8.6 x 11.5 cm) opening to a mounted volvelle. A circumferential time scale (of twice-12 hours divided every five minutes) is read against any one of dozens of cities marked on the rotating volvelle to give "l'heure de tous les Pays." Knowing the time in one city one finds the time in cities throughout the world. A longitude scale allows one to add additional locations of interest. An unusual device, in fine condition, by Engineer Gaudenzio Valle of Novara, Italy. (8169) $195.


Boxwood Version of the Traditional Nuremburg Dial Click on any image for a larger view.

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FINE FRUITWOOD DIPTYCH SUNDIAL, German, late 17th / early 18th century, stamped twice in the compass face with a "hand" mark. Measuring 4" x 2-3/4" x 3/4" (10 x 7 x 2 cm) closed, the dial is constructed of two fruitwood panels, hinged at one end. The exterior surfaces are plain, the interior punched and engraved with vertical and horizontal sundials, the numerals and decorative designs punched in black, the straight and circular lines scored then colored in contrasting red and black. The horizontal dial has three chapter rings, the hour lines spaced appropriately for 42°, 49°, and 56° North latitude. At its center is an inset glazed compass marked with principal directions "SEPT, MERI, ORIE, OCCI" and with North point showing approximately 14° magnetic declination westward (consistent with our dating of the instrument). The vertical dial has but a single chapter ring, designed for 49° North. Both dials use a string as gnomon; its bottom end is fixed, but the top can be strung through any one of eleven holes corresponding to latitudes 37° to 57°. The surfaces are decorated with numerous simulated floral patterns, each cleverly composed with a small set of punches. This diptych dial is in very fine condition, noting some old worm holes, and loss of one little foot and two simple wire clips. The dial surfaces are excellent.

This instrument represents the near end of the era of production of pocket diptych sundials in Nuremberg, for use as portable timekeepers and as devices for adjusting clocks and watches. Some of the earliest ones were made of wood, as were some of the latest. Gouk (1988) notes that very few wooden diptych dials exist, and records two early 16th century ones -- dated 1511 and 1513. In between were over two hundred years of predominantly ivory ones, in a thriving commercial activity in Southern Germany. The maker of the present dial was probably a member of the prolific Karner family, which spanned five generations of dial making. The "hand" stamp is Gouk's mark #22; this mark is found on her Catalogue #46, a small diptych combining ivory and wood, and attributed to the Karner family. (9131) $1950.


Unusual Sighting Sundial of 1816 Click on any image for a larger view.

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FRENCH SUNDIAL / THEODOLITE, 1816, signed "fait par Rivaud ingenieur le 20 mai 1816" (made by Rivaud, engineer, May 20, 1816). Made of walnut, 6-3/8" (16 cm) square and 1" thick overall, this multipurpose instrument has hinged lid with string gnomon and plumb line; horizontal chapter ring divided every quarter hour from 6am to 6pm; inset glazed compass with 360 scale divided each degree, 16-point rose, doubled needle, and automatic needle lifter; and side-mounted inclinable rectangular walnut tube with brass sights. All the layout and divisions are done by hand in ink on paper over wood. Condition is fine noting light soiling. An uncommon instrument by an unlisted maker. (8147) $1950.




An Impressive Precision Dial by Jacques Le Maire Click on any image for a larger view.

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JULIEN LE ROY'S IMPROVED HORIZONTAL SUNDIAL, French, c. 1740, signed "Jacques Le Maire de La Societe des Arts, au Genie a Paris." The substantial brass dial plate measures 7-1/4" x 9-3/4" (18 x 25 cm) overall, and is set with a glazed compass with fine eight-point rose, a broad 49-degree gnomon pierced with four pinholes and with slots to support the brass plumb on silk cord, and four pommel-headed leveling screws. The compass rose can be rotated by external pointer reading against a 0(1)20 degree scale of "declinaison occidentale" (west declination). The periphery of the dial plate is engraved with a full chapter ring, divided every five minutes from 4am to 8pm. The plumb bob hangs against a scale of latitudes, divided every degree from 35 to 60, for using the dial at other locations, with the plate tilted up or down using the long leveling screws. A list of 20 European cities and their latitudes is finely engraved on the surface. As described, this is a significant, finely crafted horizontal sundial of rather standard form. But it has additional very special features. There are three radial scales reading outwards in units from 0 to 9. And two index stubs extend an inch beyond the dial plate to the north and south, exactly in line with the 12 noon line.

This is an example of the precision sundial developed by Julien Le Roy (1686 - 1759), the premiere French clockmaker of the time, first president of the Societe des Arts. New designs of clocks and watches were achieving much improved precision, on a consistent basis, and there was a need to reset and regulate them with the true standard, i.e., sundials of high precision. In 1734, Julien Le Roy presented his new design, which was communicated to the Royal Society of London in 1736 by Desaguliers (see A. Turner, 1988, for a transcription of Desagulier's translation). For high precision a dial must be accurately leveled, and the gnomon oriented truly parallel to the earth's axis (and therefore suitably inclined and oriented to true geographic north). Le Roy's index stubs and three radial scales (called the Meridional scale and the scales of Correspondent Heights) met this need. In use the dial is placed on a horizontal table, sometime before noon, set to the latitude, and rotated until a sun-spot falls on one of the numbered intersections of the Meridional center line scale. One scribes lines on the table, along the two stubs, and connects them. Then after noon one turns the dial and, when the same pinhole casts a spot on the same intersection, draws a second line on the table. Bisecting the angle between the two lines gives the true direction to geographic north, and the dial should be set along this bisection line. To verify that it is the true meridian, one waits a few days, then checks whether a morning and afternoon passage of a particular sun-spot crosses the morning and afternoon scales of Correspondent Heights in exactly the same positions. If not, the whole process is repeated until correct.

The present dial was crafted to Le Roy's specifications by Jacques Le Maire (working 1714 - 1762), instrument maker and fellow member of the Societe des Arts. An important instrument, in very fine condition throughout. (8117) $19,500.


Time-Telling by Incense Trails Click on any image for a larger view.

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DRAGON BOAT TIMEKEEPER, Chinese, c. 19th century, made of finely carved wood, 34" (86 cm) long. The well-carved dragon has dramatic head and tail, and floral decoration throughout, and is clutching balls (pearls?) in mouth and feet. It is finished in contrasting gold and black lacquer, showing traces of red pigment underneath. Condition is good, noting several losses to the wood, including one foot. In the hollow center is a decorated wood support with two short horizontal metal rods -- from this would presumably have hung a wire basket, or perhaps a pewter pan, to support a straight stick of incense. Overall this dragon boat presents extremely well and dramatically.

This is a good example of the "dragon boat alarm" described in great detail by Bedini in his book The Trail of Time -- Time measurement with incense in East Asia (1994). Various forms are known, some serving as simple "clocks" by noting the burnt length of incense, some used with thin threads laid cross-wise over the incense, the threads supporting tiny bells which fell noisily below the vessel as each thread burned through, and some on wheels to cross the dinner table. Bedini finds reference to the dragon boat alarm as early as 1100 A.D., and into much more recent times. (8225) $6950.



Finding your way in the French Countryside Click on any image for a larger view.

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UNUSUAL PORTABLE COMPASS / SUNDIAL, French, 1837, stamped "1837 . 30 Aoust" on the brass. This traveler's instrument is carved from a single block of dense wood (walnut?) 9-1/4" (23 cm) long, with knob handle and shaped alignment index. It has an inset glazed compass with finely shaped arrow-head needle and with brass compass plate divided every five degrees and offset for 27° west declination. The adjacent horizontal sundial has brass base plate divided every 30 minutes, and small folding gnomon. Condition is fine, with a "folk art" quality.

We have not seen another compass / sundial instrument of this particular form. It is clearly French, with the early spelling of "August," and the directions E and O (for Est and Ouest). The extreme western declination (the difference in compass direction between magnetic north and "true" geographic north) of 27° was in fact never realized. About 1580, the declination had an extreme eastern value of approximately 12° (in London and Paris); it then moved westward for 230 years, reaching a peak of 23° west c. 1810, before heading back east. But some dial makers apparently extrapolated the long and rather linear increase, to arrive at values which were never reached (and see Tesseract Catalogue 76 item 20 for an English dial with 27° west declination). (8168) $1950.




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