mailto:email@example.com (Bruce Sterling)
"In 1877, Chief Signal Officer Albert J. Meyer of the U. S. Army obtained some heliograph instruments from the British for experimental purposes. Meyer sent the instruments to Gen. Nelson A. Miles, who was assuming command of the Yellowstone Department in Montana. Miles became an enthusiastic users of the heliograph. When he was transferred to Arizona in 1886 to take command of the Apache Indian campaign, he saw it as the ideal place for heliograph operations. There were few roads and telegraph lines, and widely separated army commands were often at a disadvantage through lack of communications. Miles established a heliograph communications network throughout a large part of Arizona and New Mexico, taking advantage of strategically located mountain peaks for relay stations.
"The annual report of the secretary of war for the year 1895 contains the chief signal officer's report on the Glassford expedition that established the world's heliograph distance record. It reads as follows:
"'In developing the more important electrical communication devices of the Signal Corps, other methods of signalling that are absolutely essential adjuncts have received due attention. Heliography is perhaps the most important of these methods to a rapidly moving army, operating over a country where the use of electrical instruments is inadvisable or temporarily impracticable.
'The former world's record for long range heliographing was surpassed 58 miles during the year though the zealous and intelligent exertions of Capt. W. A. Glassford, Signal Corps, and a detachment of signal sergeants by the interoperation of stations on Mount Ellen, Utah, and Mount Uncompahgre, Colorado, 183 miles apart. This unprecedented feat of long distance intercommunication by visual signals was made on Sept 17, 1894, with Signal Corps heliographs carrying mirrors only 8 inches square. It was accomplished only after much discomfort and some suffering, due to severe storms om the mountains and to the rarefied air to which the parties were subjected for ten days. The persistence, skill and ingenuity of Captain Glassford and of the signal sergeants engaged in this result are highly commendable.'
(...) "Remnants of some of the old heliograph stations are still found on the mountaintops today. At Fort Bowie, Arizona, ceremonial demonstrations of the heliograph are sometimes staged on Bowie Peak, an important relay point during the Indian campaign. The American army at first used the Mance pattern instruments from England. Later the United States had its own version that employed a leaf shutter to interrupt the light beam for keying instead of the mirror-tilting method used by Mance. The heliograph was used in the Spanish-American war in 1898. By the time of World War 1, wireless and field telephones had pretty well taken over the army's communications, but heliograph instruments were kept on hand until the mid 1920s. Some were kept at Corregidor in the Philippines for backup communication with the mainland in case of radio failure.
"The last great use of the heliograph was during the Boer War in South Africa, where both sides used it. The terrain and climate, as well as the nature of the campaign, made the heliograph the logical choice. For night communications, the British used some naval searchlights, brought inland on railroad cars, and equipped with leaf-type shutters for keying the beam of light into dots and dashes. In the early stages of the war, the British garrisons were besieged in Kimberly, Ladysmith, and Mafeking. With land telegraph lines cut off, the only contact with the outside world was via light-beam communication, helio by day, searchlight at night.
"In an effort to improve communications, five Marconi 'mobile wireless units' were sent out from England. Unfortunately, with wireless still in its infancy, these units were of little value. In the siege of Ladysmith, telegraph lines were cut off on November 2, 1899, and from then until the relieving army arrived on February 28, 1900, the heliograph was the only connecting link with the outside world. Cloudy days were tedious for the inhabitants of Ladysmith because no news could be received. One person recorded such a day in his diary, writing, 'Heavy weather had settled upon us and had blinded the little winking reflector on Monte Cristo Hill.'
"As the relieving army, commanded by Sir Redvers Buller, approached the city, his signal officer, Capt John Cayzer, attempted to establish communication by helio. There were problems with Boer operators who intercepted the British flashes. When Cayzer finally reached a station claiming to be British, he devised a test. 'Find Captain Brooks of the Gordons,' he signalled. 'Ask him the name of Captain Cayzer's country place in Scotland.' Captain Brooks, when found, did not immediately grasp the purpose of the question and remarked, 'Well, I always thought Cayzer was an ass, but I didn't think he'd forget the name of his own home!'
"Canada was the last major army to keep the heliograph as an issue item. By the time the mirror instruments were retired in 1941, they were not much used for signalling. Still, the army hated to see them go. One officer said, 'They made damn fine shaving mirrors!'"