heliograph

Directory

References

Discover

Baseball laying in the grass. Homepage blog 2010, arts and entertainment, history and society, sports and games athletics

10 Greatest Baseball Players of All Time

Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that

America’s 5 Most Notorious Cold Cases (Including One You May Have Thought Was Already Solved)

Thanksgiving Turkey with all the sides

Why Do We Eat Turkey on Thanksgiving?

Orange basketball on black background and with low key lighting. Homepage 2010, arts and entertainment, history and society

The 10 Greatest Basketball Players of All Time

earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

The 6 Deadliest Earthquakes Since 1950

A human Inuit skull in a stone chambered cairn in Ilulissat in Greenland. These ancient graves are pre christian and are at least 2000

14 Tough Questions Answered

Thanksgiving Celebration Traditional Dinner Setting Food Concept

Why Is Thanksgiving in the U.S. Celebrated on a Thursday?

heliograph

signaling device

Learn about this topic in these articles:

adaptation for military communication

In military communication: The advent of electrical signaling
…through the development of the heliograph. It employed two adjustable mirrors so arranged that a beam of light from the sun could be reflected in any direction. The beam was interrupted by a key-operated shutter that permitted the formation of the dots and dashes of the Morse code. Where climatic…
Read More

work of Mance

In Sir Henry Christopher Mance
…and engineer who invented the heliograph, a signaling device that employs two mirrors to gather sunlight and send it to a prearranged spot as a coded series of short and long flashes.
Read More