| 摘要 |
The invention relates to a device for navigation by the shadow cast by an index on an hour dial (clock face). It consists of a plate 1 etched with a circular protractor 2 on which are superposed a small plate 4 carrying an index 5 and an hour dial (clock face) 3 which both pivot on a pin 7. Use: by positioning the index 5 vertically facing the hour marking on the dial 3 which corresponds to half the number of divisions between the universal time and noon, the figure XII of the dial 3 coinciding with the 180 DEG of the protractor 2, pointing the apparatus horizontally towards the sun, with the 180 DEG side towards the sun, executing a translational movement until the shadow cast by the index 5 passes through the pin 7. The line 180-360 DEG of the protractor 2 then coincides with the south-north line (south side at 180 DEG ). <IMAGE>
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