Abstract: An adjustable sundial assembly includes a base, a saddle slidably connected to the base to move in an arc, a housing adjustably coupled to the saddle, and an equatorial sundial attached to the housing. Movement of the saddle relative to the base and/or the housing relative to the saddle calibrates the sundial to a local latitude at which the sundial is positioned.

Abstract: A sundial for telling apparent solar time and clock time across a range of latitudes and longitudes. A solar dial is formed with an index point and a noon hour point. A plurality of concentric latitude indicia are centered at the index point and at least one map indicium is overlaid by the concentric latitude indicia where the map indicium has geographic latitudes corresponding with the concentric latitude indicia on the solar dial. The solar dial also includes a plurality of solar time indicia radiating generally outward from the index point drawn with respect to the noon hour point according to the hour line equation at each concentric latitude indicia intercept. An elongated gnomon projects from the index point, whereby the sun's shadow cast by the gnomon intersects the solar time indicia in relation to the concentric latitude indicia to provide a reading of apparent solar time for the user's location on the map indicium.

Abstract: A sundial for telling apparent solar time and clock time across a range of latitudes and longitudes. A solar dial is formed with an index point and a noon hour point. A plurality of concentric latitude indicia are centered at the index point and at least one map indicium is overlaid by the concentric latitude indicia where the map indicium has geographic latitudes corresponding with the concentric latitude indicia on the solar dial. The solar dial also includes a plurality of solar time indicia radiating generally outward from the index point drawn with respect to the noon hour point according to the hour line equation at each concentric latitude indicia intercept. An elongated gnomon projects from the index point, whereby the sun's shadow cast by the gnomon intersects the solar time indicia in relation to the concentric latitude indicia to provide a reading of apparent solar time for the user's location on the map indicium.

Abstract: A self-orienting platform device is provided having a platform that is rotatably adjustably attached to a body. The device is provided with adjustable weights to ensure even rotation. The attachment between the platform and the body is such that when the body rotates, the platform rotates with it, but the attachment can be adjusted such that the user can rotate the platform relative to the body when desired. The device comprises a magnet with an attached magnetic north indicator, and can be set by rotating the platform relative to the body so that when the magnet points to magnetic north, the magnetic north indicator points to a selected marking or other feature on the platform. The platform can be rotated with respect to the body to account for the difference between magnetic and true north, so that the selected marker is aligned with true north.

Abstract: A skyline imaging system includes an image sensor and an inclination reference coupled to the image sensor. The inclination reference provides a righting moment for the image sensor and establishes a predetermined orientation for the image sensor relative to the Earth's gravity vector. A heading reference determines an azimuth heading for the image sensor.

Abstract: A skyline imaging system includes an image sensor and an inclination reference coupled to the image sensor. The inclination reference provides a righting moment for the image sensor and establishes a predetermined orientation for the image sensor relative to the Earth's gravity vector. A heading reference determines an azimuth heading for the image sensor.

Abstract: This invention represents an improvement to an equatorial sundial comprising an independent simultaneous single scale indication of both time and date as represented from a primary and secondary gnomon. This allows one unfamiliar with the physics of an equatorial sundial to with simple observation quickly assess both time and date as a singular measurement. The sundial displays conventional time measurement on a single scale transcribed on the equatorial ring from a primary gnomon aligned with the polar axis. The improvement includes a date scale transcribed on the primary gnomon that is cast a shadow from the secondary gnomon comprised of the upper equatorial ring. Since the sun maintains an essentially equivalent angle of declination throughout the day, the shadow cast by the upper equatorial ring (secondary gnomon) on the primary gnomon (containing the date scale) remains consistent in position and date can be observed at any time of the solar day.

Abstract: Watch comprising an arrangement for detecting the direction of the terrestrial magnetic north formed by a permanent magnet and at least two magnetic sensors (34, 36) arranged for detecting the flux of the magnetic field of the magnet. The watch moreover comprises electronic management and control means serving, as a function of the signals coming from the two sensors, to control indicating means (16) arranged so as to indicate either a selected geographic azimuth or the direction of a predefined locality, in particular Mecca.

Abstract: A digital sundial displays the current solar time in digits, words, or pictures. Two closely-spaced parallel masks project different images depending on the angular position of the sun in the following way: The first mask, a regular array of thin vertical slits, casts a striped light pattern onto the second mask. This light pattern is independent of the height of the sun. The second mask is composed of narrow stripes of the digits, words, or pictures to be displayed. The striped pattern of sunlight cast by the first mask illuminates exactly those stripes of the second mask corresponding to the image representing the current time. The light shining through both masks is projected onto a translucent viewing screen mounted closely behind the second mask, which results in a digital display of the time. A plate of light-refracting material can be inserted between the two masks, effectively linearizing the motion of the light pattern cast onto the second mask.

Abstract: A watch including an arrangement (14) indicating the terrestrial magnetic north. Such terrestrial magnetic north indicating arrangement is fitted into the watch case (32) in a lateral peripheral region of the horological movement (2). Specifically, the terrestrial magnetic north indicating arrangement comprises a permanent magnet (16) mounted on a shaft (18) and a direction indicator (24) fixed to such shaft. In accordance with three specific embodiments, the watch according to the invention enables, firstly, indication of the north direction, secondly, any direction whatsoever permitting the user to follow a predetermined direction and, thirdly, the direction of Mecca from at least one place on the terrestrial globe where such user is located.

Abstract: An apparatus for making drawings on a drawing carrier, for example a sheet of transparent paper, via a device for producing points or lines such as a pen or pencil, including a drawings surface which temporarily accommodates the drawings carrier and which is variable with respect to inclination relative to a support surface. The apparatus also includes a drawing aid in the form of a template which is displaceable over the drawing surface wherein the drawing aid is connected to a data receiving machine and is adapted to be activated by the pen for outputting data to the data receiving machine. The drawing aid may have at least one digitization plane associated therewith wherein data transfer can be activated at the meeting point between the drawing aid and the pen or the like.

Abstract: A direction indicator includes a base defining four edges that extend parallel to a horizontal surface on which the base is placed and form portions of respective sides of a rectangle, a bearing indicator which is selectively positionable on the base for carrying compass bearing information, and a gnomon supported in a predetermined position relative to the direction indicator. The bearing indicator may further contain time markings in the event that it is used as a sundial. The base is adapted to be placed in a predetermined orientation on a horizontal surface. For a given orientation of the base, the direction indicator can be appropriately positioned relative to the base by reference to the direction of a shadow cast by the gnomon at a predetermined time of day and by reference to the bearing of the sun at that predetermined time of day.

Abstract: An accurate, easy to use solar compass which permits a user to locate true north or to locate azimuth lines. The user calculates the solar time and determines the declination of the sun from the emphrimis. The user adjusts the compass to compensate for the declination of the sun and the physical location of the user. The user thus determines true north accurately using a shadow cast by a stylet. An important aspect of this invention is that it is an accurate solar compass.

Abstract: An apparatus which can be carried to a field sight to locate current and future positions of geosynchronous satellites orbiting the equator in the Clark Belt Altitude. The apparatus corrects the error in viewing angle by providing corrections in longitude and latitude deviations caused by the location of the antenna. The apparatus will provide the user a means of accurately locating a satellite with regard to existing terrain and the obstacles which would interfere with signals between the ground position and the satellite.

Abstract: A universal sun-clock is described comprising a base, on whose surface there are present a sun-dial (consisting of a clock-face and a time-pointing tongue) and a reference mark for orienting the sun-clock according to the longitude and an upright (hinged to an end of a support which can be drawn out from the base) bearing a semicircular sector, free to rotate around a pin, on which sector a latitude scale (graduated from 90.degree. of latitude North to 90.degree. of latitude South) is marked: an index integral with the upright allows to read the latitude on the semicircular sector. When the sun-clock is in a working position the support is drawn out from the base and the upright is rotated around its hinge until it is perpendicular to the base, whereas when the sun-clock is in a rest position, the support is retracted into the base and the upright, by rotating round its hinge, is pulled down onto the base.

Abstract: This invention concerns a compass watch as well as a bezel specifically intended to fit out such a watch. The invention comprises at least one time indicating element (4) kinematically driven in rotation by a mechanical or electromechanical horometric movement, and particularly intended to be pointed towards the sun, and direction indicating means (N, S, W, E) arranged on said watch enabling one to know, as a function of the orientation of said indicating means (4), the direction of at least one of the cardinal points, and is characterized in that it includes correction means (52; 16, M) for the positioning of the cardinal points, adapted to take into account the equation of time and to correct any variation between true solar time and the legal or local time of day. The invention is applied to a watch, preferably of the mechanically or electromechanically driven type.

Abstract: A multi-dimensional astral position finding device for facilitating viewing selected sky areas such as constellations in the zodiacal band and elsewhere. A device which in combination with a pre-selected field of view facilitates positioning of the eye of the observer with respect to the north/south axis of the earth, the latitude of the observer's position, and time. The position finding device is pivotally mounted on a sky viewing frame or system, the position of the device being directly affected by gravitational forces, its location precisely determined with respect to the north/south axis of the earth by a compass carried by the device and serving as weight means for enhancing the gravitational effect to actuate positioning of the device, said device including indicia on a surface thereof arranged on radii extending from the axis of the pivotal mounting to facilitate desired inclination of the viewing frame relative to the horizon.

Abstract: A solar compass device having a first disc member provided spaced apart time markings indicative of the time of day and disposed in a counterclockwise direction in a circular ring pattern thereon. A second disc member is rotatably displaceable with respect to the first disc member to permit rotational displacement between the first and second disc members with the members disposed in substantially parallel planes. A single fixed indicating marking is provided on the second disc member and aligned with a south end of a north-south radius passing through a center point relative to the ring, and the ring. In operation, the first disc member is oriented with one of the 12 o'clock marking, aligned substantially in the direction of the sun, with the fixed indicating means having been aligned with a marking indicative of approximately the time of day. With the discs so oriented, the north end of the radius is automatically aligned in the direction of the north pole.

Abstract: A watch adapted for use as a compass in addition to indicating local and remote times. The watch is provided with a dial, supplemental pointer, a microprocessor, and a keyboard for introducing selected data and operations into the microprocessor. The watch-compass and method is used for time and space orientation, in navigation such as for checking a magnetic compass or gyroscope, for calculation of azimuth angles, and for orientation of the user in unfamiliar locations.

Abstract: The invention concerns the field of the solar shadowscopes. The apparatus according to the invention is characterized by the fact that the conditions of sunshine are recreated by the displacement of the light source in the relation to the apparatus and that the final position of the light source is given by the real position meeting exactly a given theoretical position of the shadow on the date scale and on the hour scale of a point "T", actually shown by the point of intersection of two wires set in the light beam.Application to the determination of the shadows on a model.