11. The designer described the Solar Beacon as a " heliostat ", not a " heliograph ". 12. In open warfare, visual signalling ( employing signal flags and the heliograph ) was the norm. 13. The handy discs can also be used as impromptu heliographs to signal your forces trapped behind federal lines. 14. The heliograph uses a mirror to Naval ships often use signal lamps and Morse code in a similar way. 15. However there is little evidence that " heliograph " here is other than a misspelling of " holograph ". 16. The Grugan and Pursell heliographs used shutters, and the others used movable mirrors operated by a finger key. 17. The next day a heliograph was spotted signalling from Fort Pearson and a makeshift apparatus allowed Eshowe to reply. 18. This high point was used by the U . S . Army in the 1880s as a heliograph station. 19. The Spanish garrison at Igueriben was cut off, but could communicate with the fort at Annual via heliograph . 20. Other historical exhibits included five heliographs by Ni�pce with modern photographers such as Captain Thomas Honywood also being present.
