The Astrolabe is the most sophisticated of all ancient scientific instruments. Designed circa 170 B.C., its use quickly spread in navigation, surveying and astronomy. Consisting of a map of the sun and stars rotating above a map of the sky, the Astrolabe is a model of the heavens which charts the movements of the celestial bodies using the sighting device. The time and latitude can be calculated from the position of the sun or stars. For any given date and time the position of the celestial bodies can be calculated. These positions have been adapted to meet the actual positions of celestial bodies today.

The Mariner's Astrolabe: Developed by the Portuguese in the late 15th century, the sea or mariner's astrolabe was designed spefically for making latitude measurements at sea, using the sun or a star. It contained neither a model of the heavens or a calcalating device, and was originally made in plate form, from wood or brass, with an alidade like the conventional planispheric astrolabe. By 1517 it was made from cast brass pierced or fretted out to reduce wind resistance, and the alidade had been modified. The weight was increased towards the bottom, which increased the inertia in conditions of sea or swell, making the instrument steadier while in use.

The Eight Plate Astrolabe: The astrolabe with six latitudes, one universal horizon, one terrestrial allows one to navigate and to survey at different latitudes anywhere in the northern hemisphere. The astrolabe and 8 interchangeable plates come in a velvet lined birch box.

The Sundial, one of the earliest scientific instruments known, measures time by a shadow cast from an indicator onto a surface that is marked of in intervals. The most common form of sundials measure the hour angle of the sun. The rod or string that casts the shadow is called the Gnomon and is mounted so as to parallel with the axis of the Earth.

The Drawbridge Sundial: Slide the drawbridge first up then the top forward, to open the dial, Helios, god of the sun is pulling his chariot across the sky. The line of the string from Helios's hand points south. With the drawbridge level to the ground, the shadow of the string tells the time.

The Sundial Cannon: Made of solid brass with a marble base, dia. 8", ht. 5-8". This working model is based on the cannon of the middle ages which was typically located in the town square. At noon the sun rays were focused by the lens to fire the cannon and announce the hour. All that is needed is two grams of black powder and primer to fire this Sundial Cannon.

The Ring Dial: Our ring sundial, in the style of elegant 17th century European dials, lists the latitude of major cities for the traveler. Four moveable parts adjust to discern the time. The outer ring adjusts to the latitude. This is called an equinocial dial because it has equal spacing between the hour lines. The hour ring is kept parallel to the Equator by adjusting the dial to the proper latitude. It is a unversal dial, usable at any location or latitude.

The Ship Dial: This rare sundial adjusts to the time of year by tilting the ships mast, and to latitude by adjusting the plumb line through the mast. Sights located in the fore and aft castles direct the sun's rays, as the bead on the plumb line indicates the time. The instrument appears to have been a modification of the Arabian Zaourac meaning; small ship(latin; navicula).

The Canterbury Peg Sundial: When the Danes ravished Canterbury, England in the year 1011, they imprisoned Archbishop Alphege and later murdered him in prison. When the Garth Monastery at Canterbury was restored in 1938, his tomb was opened, and in it was found a little silver pegdial hung from a golden chain. Obviously over nine and a half centuries old this became known as " the first pocket watch". The Gnomon is a removable peg which is thrust through the hole at the top of each column for the appropriate month. The dial, hanging plumb is turned towards the sun until the shadow of the gnomon falls below. Thus the dial shows the times of the medieval unequal canonical hours which were set aside for prayers.

The Quadrant Dial: The original idea for the quadrant is attributed to Ptolemy. He designed a quadrant which used a plummet for vertical allignment, and, while there no evidence he built such an instrument, his plans were adopted with the rest of his writings.

Quadrants were used by astronomers until the end of the 18th century. At least three forms of quadrants, which could be used for telling time, were known in the middle ages. This type was known as quadran venus (the old quadrant). Two changes have been made from the traditional instrument. A mount from which it can be hung, and an internal sighting tube.

This working instrument is built around a ball of malachite, the stone prized since the time of the ancient Egyptians, Greeks and Romans for its decorative markings; used as an inspiration for valuable obets d'art. This ingeneous instrument is an accurate reproduction of the armillary sphere made by Theodore Heath in 1780. The path of the sun as it rises and sets is demonstrated for any location, latitude, or season, showing the Tropics of Cancer and Capricorn as well. The "cage" represents the celestial sphere, with zodiac and meridian rings, while the malichite ball represents Earth. Created in pewter with, marble, or gold plated with a brass and walnut base, it is equally impressive in a classic or contemporary setting. As seen in "The Adventures of Baron Von Maunchausen".

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