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Our largest and finest 8-inch sextant is this 8-inch (20 cm) radius sextant reproduction. It features six filters, a scale magnifier, and a micrometer drum readout. The sextant weighs 5 pounds (2.3 kg), measures 11 3/8 inches (28.9 cm) tall, 10 1/2 inches (26.7 cm) wide, and is 4 7/8 inches (12.4 cm) deep. |
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| A micrometer drum mechanism is used to precisely alter or read the azimuth angle. The sextant features a worm gear drive that can be overridden for large angular movements. To create smooth, large angle movements you can disengage the gearing by squeezing the mechanism. This photograph also shows the Stanley London engraving. |
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The 8-inch sextant has six filters mounted on heavy swing-arm mounts.
A bright and sharp image is produced by the telescope, and it can be extended to focus and collapsed for storage.
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To align the optical path there are three inset adjustments on the index mirror. The mirrors are aligned at the factory and checked prior to shipping. |
| When the sextant is set to zero degrees, the image through both optical paths as viewed through the telescope, align to produce a single image. The image is split in half when the index arm is moved. When viewing two objects, such as the horizon and a celestial body, the index arm is adjusted until the two are superimposed. Then the angle between the two objects is read by the micrometer drum. | |
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The micrometer rack is cut directly onto the limb of the sextant. The hardwood handle of the sextant has a brass plaque that can be custom engraved. |
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The sextant is accompanied by a beautiful large handcrafted hardwood storage and display case. The case features two brass latches and a handle, and has a green felt lining. "Nautical Sextant, Stanley London, 1920" is engraved on an oval brass plaque on the top of the case. |
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The handsome handmade hardwood case can serve to either store or display the 8-inch sextant.
Although the sextant is fully functional, it has not been calibrated and is not intended for navigation. A nearly identical vernier readout version of this sextant is available. The only difference being the micrometer drum vs. vernier readouts on the index arm. The micrometer drum represents the design of modern sextants while the vernier readout version is found in older designs. |
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