U.S. NAVY MK III SEXTANT

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~ C. Plath Pedigree ~
UN-USED

Presented is our first opportunity ever to offer an absolutely new and flawless “Collector Quality” example of a U.S. Navy MK III sextant. We have sold top quality MK III’s before, all in exceptional condition, but this is the first new one we’ve ever seen. It is Serial Number 2365 made by Scientific Instruments of Milwaukee, WI. All their MK III instruments made
by them have their tag riveted on the index arm. The sextant comes complete with all its original accessories including a spare set of mirrors, a sighting circle, extra bulbs, and its Butternut wood case. The matching certificate is dated 11/16/90. Six years ago I used one with good results when I went on a brief cruise on a Spruance Class destroyer, USS CARON, DD 970. I appreciated its lighter than average weight, and comfortable handle.

POVENANCE: This sextant was acquired from the estate of the prior owner
who purchased it at auction held at the Charleston Navy Yard, South Carolina after its closure in 1996. It was never used by him, and remains in it original unused state.

SOME BACKGROUND: At the time the design of this sextant was adopted around 1975, I was a member of the Navy Department’s Navigation Symposium Board, and remember the criteria
that was established. They coincided with already existing technology in the civilian maritime community. In total, the new design was far advanced from the ubiquitous Navy WW II standby, the Navy MK II. The Tamaya MS 733 and the C. Plath sextants met these criteria as
did a few others, but there was strong feelings in government procurement then to “Buy American” in contrast to today’s World Economy. Consequently, two American manufactures were selected for the MK III program, M. Low of which little is known other than they were a New York dealer in nautical instruments, and Scientific Instruments, of Milwaukee, WI. These
sextants were made under license by C. Plath, Hamburg, Germany who may have provided the tooling. C. Plath aficionados take note, the design is clearly the same as the C. Plath Classic sextant down to the last detail other than its ergonomic handle and large size high impact resistant case. This pedigree is noted on page 119 of the book by Friedrich Jerchow, “From
Sextant to Satellite Navigation, (1837-1987) 150 years C. Plath”. At last report, this design, was no longer being issued because the last maker ceased operations in January, 2008. In the recent past, two were issued to U.S. Navy ships on commissioning. They cost the Navy over $4300.00 according to Scientific Instruments before they closed. Consequently, this may be the last new Navy MKIII in the world. Listed are what were “state of the art” design features, that are still the standard today:
Light weight
Large size index mirror
Large size horizon mirror
Lighting system
Vernier reading to 6 seconds
Handle for ergonomic fit
Wide angle telescope
Non-adjustable instrument error of less than 20 arc seconds
Military high impact absorbent case

CONDITION: The sextant is brand new and shows no discernable evidence of use. All its machinery works well. Both fitted mirrors are NEW. It comes with a set of new replacement mirrors. The numbers match on the certificate. The lighting works. The nicely finished Butternut case shows a couple of small dents and a few scratches. The index error is negligible,
and there is a touch of side error which is a good thing. The last certificate is included. No locks are fitted to this Navy style case.

STAR RANKING: This sextant and case rates
as “NEW”

This is fine NEW sextant in perfect condition and is backed by our guarantee of satisfaction. It requires someone who can appreciate the fine points of a sextant, and is willing to pay an appropriate price for this level of quality and excellence.

DOES MY OPINION COUNT: We are one of the few company’s still selling navigation instruments that know anything about them. For purposes of judging whether my opinion counts, I was the editor of the chapter on sextants of the 1977 Edition of “Bowditch”, The American Practical Navigator, NAVPUB 9; a member of the U.S. Naval Academy Navigation Symposium Board, 1975 -1978; the author of a book on marine sextants, Cornell Maritime Press,1975, and the founding president of Nautech Maritime Corporation which partnered with Tamaya of Japan in the introduction of the MS 733 Spica, the MS 833, Jupiter, MS 933 Venus sextants and the famous NC-2 navigation computer, in the U.S. market. I also am a retired Master Mariner, and held a U.S. Navy “D” Qualification as a Senior Skipper – Oceans. From 1995 until 2001, I served as a Varsity Offshore Coach at the U.S. Naval Academy.

U.S. NAVY MK III SPECIFICATIONS:
Measuring Range: -5 to 125 degrees
Accuracy: Tested to +/- 20 arc seconds
Telescope: 2 x 40 Coated optics
Frame: Aluminum with black enamel paint and white numbers.
Micrometer Drum and Vernier Scale: reads to 6 arc seconds
Index Mirror: 57 x 42 mm with spare
Horizon Mirror: 57mm diameter with spare
Shades:
3 for index mirror
3 for horizon mirror
Illumination: Yes

Weight sextant: 2.5 lbs, Weight case in case 12.5 lbs.

INCLUDED ARE:
1 Sextant frame
1 2 x 40 Scope
1 Mirror adjustment tool
2 Spare mirrors
2 Bulbs
1 Brush
1 Mahogany sextant case. No locks
1 Certificate dated 1990

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Shipping & Packaging

The cost of shipping, packing, handling, and insurance to your destination, will be calculated point to point and is an additional charge. You may email us to get these costs. We price our shipping honestly, but we expect to be reimbursed for the nominal cost of packaging materials and handling.

Our Unconditional 'No Nonsense' Guarantee

If not completely satisfied with your purchase it may be returned, if without damage, within three days of receipt in its original packaging. Return items must be insured for their full value. Only a prior email authorization by us for the return is required. Shipping charges are refundable if due to our error within the continental United States.

International buyers welcome, but inquire first. We have satisfied customers worldwide.

Standard Forms of Payment

Bank wire transfer, cashier’s check, money order, or personal check in which case the item will be held until cleared. Our prices are quoted net to us so that the use of credit cards or PayPal incur extra charges. Terms on overseas sales are different.

Established in 2003

Celebrating 18 Years of Exellence in Nautical Antiques

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