(Difference between revisions)
m (New page: IEEE GHN Category Category:Telegraphy)
|(One intermediate revision by one user not shown)|
|Line 1:||Line 1:|
Latest revision as of 21:24, 14 January 2013
A system of conveying information by visual signals, usually using towers with flags or shutters
Pages in category "Optical telegraphy"
The following 2 pages are in this category, out of 2 total.
Media in category "Optical telegraphy"
This category contains only the following file.
- Optical Telegraph Ol...