Abstract: A demonstrative teaching apparatus for teaching the relationship between variable pictorial and/or graphic displays and their respective numerical values, in which the entire apparatus is positioned within an apparatus housing. The apparatus housing incorporates viewing areas on its front and rear sides so as to provide optical display of the relevant teaching portions of the apparatus. The front viewing area reveals the position of the segmented display while the rear viewing area reveals numerical indicia corresponding to the display of segments appearing through the first viewing area. The segmented display and, in turn, its respective numerical indicia, can be increased or decreased by forward or reverse rotation of a circular disk. The circular disk is precluded from excessive rotation in either direction through stopping mechanisms which limit the inadvertent winding or unwinding of the segmented display.

Abstract: A stack of sheets, each sheet from the next to lowermost upwardly corresponding to a successive binary place, the lowermost sheet carrying array of decimal numerals, a pivot connecting the sheets for relative rotation, and a window in each sheet above the lowermost configured to expose in one position of sheet movement the decimal corresponding to the binary place of the respective sheet and additional decimal numerals.

Abstract: An instrument includes three surfaces arranged in contact with one another and rotating around a common coaxial center. By appropriate reciprocal rotations of the three surfaces, it is possible to determine, directly and simultaneously, at any latitude and longitude and during the entire course of the year, at the various solar times, the time of sunrise and sunset, the altitude and azimuth angles of the sun, the points to trace daily trajectories of the sun, the optimum inclination of a plane placed in a North-South direction to enjoy maximum insolation within a predetermined time period, as well as the correspondence between the actual solar time and the conventional time of the selected site. The instrument makes possible a rapid and direct determination of these values without having to resort to various tables or to analytical calculus.

Abstract: A device for allowing a worker to lay out parallel lines which are to be spaced apart throughout by a constant distance S, and which lines include parallel but offset sections being joined by intervening angled sections with one of the lines of each offset section being extended to overlap the other by a distance D in order to maintain the lines parallel and spaced throughout by the distance S, the device including a first disc having indicia disposed on one side thereof which correspond to the slope and run of an angled section, and indicia disposed on the other side thereof which corresponds to the overlap distance D with the device further including two other discs, each of which is disposed over one of the surfaces of the first disc and including indicia corresponding to the rise of an angled section, thereby allowing a worker to align the indicia corresponding to the run or slope with that corresponding to the rise of an angled section, the device allowing a worker to obtain directly therefrom the requis

Abstract: Disclosed is a circular computer and system for determining the sun angle relative to the horizon from any given place and at any time. The computer includes transparent, rotatably mounted discs on both sides of the circular disc member. Printed on one side of the circular disc member are outer and inner circular sets of indicia respectively representative of site longitude and Greenwich Mean Time. Printed on an associated one of the rotatable discs is a set of indicia representative of Solar Time. Printed on the other side of the circular disc member are parallel lines representative of latitude between diametral representations of North and South poles. Elliptical lines extending between the North and South poles are proportionally disposed on the surface to scale Solar Time in hours. Printed on the other associated one of the rotatable discs are parallel lines representative of sun angle and a perpendicularly arranged sun elevation line.

Abstract: The present invention relates to a time card computer that is adapted to compute or calculate the total time worked by a worker over a specified time period and in the process compensates or subtracts for interim time out periods. The time card computer of the present invention is of the circular or disc type and includes a stationary total time worked scale, a movable time reference scale disposed radially inward of said total time worked scale and a movable time out or subtracting scale disposed radially inwardly of said time reference scale.In computing the total time worked by a worker over a specified period of time, the time reference and time out scales are indexed relatively to the stationary total time worked scale.

Abstract: This invention relates to a manually operable calculator; used to determine percent scores and to weight tests, comprised of a circular disc having a centrally pivoted rule. The disc has an outer periphery of numerals indicating per cent scores, the radii of numerals below 100 per cent indicating perfect scores, the radii of per cents other than one hundred indicating raw scores, and numerals on the rule corresponding to numerals on the radii below 100 per cent.