Optical telegraph from the time of the Napoleonic war

In the period 1807-1814 Denmark-Norway came to war with England. A few years earlier Admiral Nelson had been in Copenhagen and destroyed a large part of the Norwegian-Danish fleet.
As a result of this war action, the union of Denmark/Norway came into a war with England in the following years, and British warships came to the Norwegian coast.
In an attempt to send messages between Norway´s largest cities, an optical telegraph was built.
This flap telegraph could send visual signals to stations between the coast from Kristiania (an old name on current capital Oslo) to Bergen.
In an advanced system, different numbers could show both simple numbers and multiple digits depending on how the flaps were in relation to each other.
Each number represented a message, and with the aid of a signal book, operators could send messages to the next station.
The optical telegraphs could have a distance between them up to 16 km. With Longer distance,​ the operators could not interpret the signals clearly.
Using these flap telegraphs, messages could go between these cities in two to three hours.
At Bømlo in Sunnhordland, there were three such optical telegraphs. In the south it was Espevær, then Sønstabø in the middle and in the north at Brandasund.
The pictures were taken today on a trip where this optical telegraph was presented. As the pictures show, we were lucky and got a nice rainbow while we were in the area.