| 摘要 |
The invention relates to an apparatus making it possible to trace out, without calculations or geometrical constructions, the graduations of a sundial at any point on the Earth, whatever the orientation and geometrical nature of the chosen surface. It consists of a transparent drum 1 on which the two families of graduations 2 and 3 are painted, a point light source 4 and a stowage device 5 which enables the whole to be fixed to the end of the shaft of the future sundial. If this shaft has been correctly oriented (that is to say parallel to the axis of the Earth) by whatever method, the shadow of the graduations 2 and 3, which is projected onto the surface of the dial by the source 4, will construct the scales for reading the time which may be read off by any graphical method. <IMAGE>
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