CRAFT FOCUS – Sundial Compass

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How to Use a Sundial Compass

The compass and the sundial are two completely different instruments which were built for entirely different uses.

The compass is an instrument that is used for navigation and includes a free-floating magnetized needle which, when held level and still, aligns itself with the earth’s magnetic field and in doing so, points approximately north.

The sundial is an instrument that is designed for a specific location on the earth and permanently installed there so that the shadow of one of its parts indicates the hour of the day. Of course, this only works during daylight hours and when the sun is making shadows.

Combining the Function of a Sundial and Compass

A sundial compass is a combination of these two instruments, consisting of a portable sundial which is attached over a compass via a hinge. There are some adjustable legs that need to be used to level the instrument if not on level ground. The gnome is hinged and needs to be put in the up position where it locks into place. There should be what looks like a protractor that is to the right of the gnome that is on a hinge, and this needs to be flipped up as well. The protractor is used to set the sundial to the correct latitude angle, while the compass is used to find true north based on the area’s magnetic north declination.

Once your sundial compass has been leveled, set to the correct latitude, and to true north, a shadow will be is cast onto the sundial’s face by the gnome. For use in the southern hemisphere, the same procedure is followed with the exception that true South must be found instead of true North.

Storing & Transporting our Sundial Compass

When the instrument is not in use, the needle brake should be set to ensure that the needle bearing is not damaged in transit. To accomplish this, the lever on the side of the compass is simply slid over, locking the needle in place. Then, the sundial and gnome are folded over for storage.

Allowing for Location in Your Sundial Compass “Reading”

The time shown on the sundial may not match the time on your clock or watch, however. This is because the time shown on the sundial is actually the “local apparent time” due to the fact that times are based on the position of the sun at the center of the time zone. The sundial will be ahead if you are on the east side of the time zone and behind if you are on the west side.

CRAFT FOCUS – Sundial Compass – Related Products

The following items are used in the above-article, or may provide added reference and helpful information.

Brass Compass, 2-1/4" Diameter

Brass Compass, 2-1/4" Diameter

Product No. 4553-401-401

$19.95

Don't get lost in the woods anymore! If you take one of our new period-correct compasses, you'll always head in the right direction! Made of solid brass with old style dials and needles, this is an important accessory for your possibles bag. This larger model is patterned after an original and marked "Stanley/London" on both the top and the vintage styled dial. Plus, the removable top is etched with the Robert Frost poem, "The Road Not Taken", and it can be screwed to the bottom while the compass is in use.

Brass Compass, Hinge Top 1-3/4" Diameter

Brass Compass, Hinge Top 1-3/4" Diameter

Product No. 4553-401-402

$17.50$14.88

Take our authentic, early style compass, and you'll always be headed in the right direction! This compact, solid brass model measures 1-3/4" in diameter and features a hinged cover, etched brass dial, sliding needle lock, and suspension ring to secure it safely to your shooting bag or belt. An important accessory for trekkers and explorers alike!

Lewis & Clark Pocket Compass

Lewis & Clark Pocket Compass

Product No. 4553-401-404

$42.50$36.12

This authentic replica is an exacting copy of the famous compass that guided the Corps of Discovery during 1803 and 1804 on their search for a water passage to the Pacific Ocean. Without a doubt, this was the most fruitful "failed" expedition in American history!

The aged bronze compass features a period correct, antique printed dial, is 2-1/2" in diameter, and is fitted with a locking lever that restricts movement and prevents damage of the needle during travel. Mounted in a handsome, 3-1/4" x 3-1/4" x 1-1/8" mahogany case with faux worm holes and hinged lid, it is a wonderful gift that will be treasured by any modern explorer!

Original Compass at the Smithsonian

Among the collections at the Smithsonian Institution's National Museum of American History is the actual original compass used by Lewis and Clark on their great expedition. This brass and silver compass, set in a mahogany box was made by Thomas Whitney of Philadelphia and was used by William Clark. It is one of the few surviving scientific instruments from the expedition organized by President Thomas Jefferson in 1803 to explore the Missouri River and search for possible routes across the continent to the Pacific Ocean.

Following the History . . .

The following spring, Meriwether Lewis and William Clark and the Corps of Discovery set out from St. Louis to survey the Northwest portion of the Louisiana Purchase. Some time after completion of the expedition, Clark gave the pocket compass to Captain Robert McCabe, an army man with whom he had dealings in the 1820s. It passed down through the McCabe family and eventually to the Smithsonian Institution.

Learn more about the Lewis and Clark Compass & the Corps of Discovery

Brass Sundial Compass, 1-3/4", 1750s Era

Brass Sundial Compass, 1-3/4", 1750s Era

Product No. 4553-401-403

$29.95$25.46

This is an authentic replica of a 1750 era, folding style instrument which shows direction as well as time. It features a folding "gnomon" and antique style face, hand-lettered on parchment coloured paper in the original hues of red and blue. This striking and unique instrument is housed in a beautiful solid brass case, 1-3/4" in diameter and is suitable for engraving.

2017-01-30T14:13:16+00:00