Latitude. 17th century device for determining latitude. The metal bar is attached to the centre of the disc. An observation of the rising of a known star is made and its location plotted using the bar against its known declination. The angle read off from the edge of the disc as pointed to by the bar gives the latitude. This illustration was first published in De magnete by William Gilbert,printed in London in 1600 | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Middle Temple Library |
Taille de l’image : | 3933 px × 4606 px |
Model Release : | Non requis |
Restrictions : | - |