The optical telegraph or semaphore (a composition of the Greek words 'sign' and 'carry') was the first usable optical telecommunication apparatus. Although the principle was already described in antiquity is not sure whether it was really used at that time. At the end of the 18th century Frenchman Claude Chappe designed a semaphore, also known as the Chapptelegraph, and in the following years a chain of semaphores connected Paris to Lille. Napole0n understood the importance of this communucatiesystem and had built a 5,000 km network across France. The Chappetelegrafh played a big role for 50 years, until being replaced by the electric telegraph.
The semaphore inspired artist Philippe Druez (ON1PHD) in a mixed / multi-media project. 

The iSemaphore Project
In this project a communication network is built in which the initial message is sent using a semaphore. This mechanical message is observed from a hill by a camera with telelens. The optical image is decoded using an image analysis app and send over the world using a network of shortwave radio stations.
A part of the installation is of course a design inspired by Chappe's semaphore, but also the associated code book, the image recognition software and the conversion to morse code. Ultimately, the system will be operational by a performance in which every half hour messages are transmitted. The messages are also tweeted on @The_iSemaphore.
The installation will be demonstrated on April 26, exactly 220 years after the first semaphore was inaugurated in France. That day messages will be sent from a hill near Zwalm (Meilegemstraat, Zwalm). A second performance will take place on June 20 during the open house of the Academy of Fine Arts, Offerlaan 3, Ghent.

More information:
philippedruez.be/isemaphore (Dutch)
facebook.com/isemaphore
Twitter: @The_iSemaphore
SALUT, the iSemaphore gazette ed. 0
SALUT, the iSemaphore gazette ed. 1 (Dutch)
SALUT, the iSemaphore gazette ed. 2