121:
the target was hidden by the unsilvered spot. Keeping their head still, they then adjusted the aiming rod so its cross wires bisected the target. They then turned up the sighting vane, which covered the cross wires with a diagram of a cross, and aligned the mirror with the tangent and elevation screws, so the small shadow that was the reflection of the unsilvered spot hole was on the cross target. This indicated that the sunbeam was pointing at the target. The flashes were produced by a keying mechanism that tilted the mirror up a few degrees at the push of a lever at the back of the instrument. If the Sun was in front of the sender, its rays were reflected directly from this mirror to the receiving station. If the Sun was behind the sender, the sighting rod was replaced by a second mirror, to capture the sunlight from the main mirror and reflect it to the receiving station. The
471:
flashes, detecting the flashes at the receiving end, and transcribing the flashes into the message were all done manually. One notable exception â many French heliographs used clockwork heliostats to automatically steer out the sun's motion. By 1884, all active units of the "Mangin apparatus" (a dual-mode French military field optical telegraph that could use either lantern or sunlight) were equipped with clockwork heliostats. The Mangin apparatus with heliostat was still in service in 1917. Proposals to automate both the modulation of the sunbeam (by clockwork) and the detection (by electrical selenium photodetectors, or photographic means) date back to at least 1882. In 1961, the US Air Force was working on a space heliograph to signal between satellites
320:
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27:
142:, where both sides used heliographs, tubes were sometimes used to decrease the dispersion of the beam. In some other circumstances, though, a narrow beam made it difficult to stay aligned with a moving target, as when communicating from shore to a moving ship, so the British issued a dispersing lens to broaden the heliograph beam from its natural diameter of 0.5 degrees to 15 degrees.
357:
heliographs used two tripods, and the others one. The signals could either be momentary flashes, or momentary obscurations. In 1888, the US Signal
Service reviewed all of these devices, as well as the Finley Helio-Telegraph, and finding none completely suitable, developed the US Signal Service heliograph, a two-tripod, shutter-based machine of
475:
beacons were later moved to Sather Tower at UC Berkeley. By June 2012, the public could specify a "custom show" of up to 32 "on" or "off" periods of 4 seconds each, permitting the transmission of a few characters of Morse Code. The designer described the Solar Beacon as a "heliostat", not a "heliograph".
470:
Most heliographs of the 19th and 20th century were completely manual. The steps of aligning the heliograph on the target, co-aligning the reflected sunbeam with the heliograph, maintaining the sunbeam alignment as the sun moved, transcribing the message into flashes, modulating the sunbeam into those
315:
The simple and effective instrument that Mance invented was to be an important part of military communications for more than 60 years. The usefulness of heliographs was limited to daytimes with strong sunlight, but they were the most powerful type of visual signalling device known. In pre-radio times
120:
There were many heliograph types. Most heliographs were variants of the
British Army Mance Mark V version (Fig.1). It used a mirror with a small unsilvered spot in the centre. The sender aligned the heliograph to the target by looking at the reflected target in the mirror and moving their head until
145:
The range of a heliograph depends on the opacity of the air and the effective collecting area of the mirrors. Heliograph mirrors ranged from 1.5 to 12 in (38 to 305 mm) or more. Stations at higher altitudes benefit from thinner, clearer air, and are required in any event for great ranges,
348:
the possibility of performing communication by heliograph over a heliograph network aggregating 2,000 mi (3,200 km) in length. The network of communication begun by
General Miles in 1886, and continued by Lieutenant W. A. Glassford, was perfected in 1889 at ranges of 85, 88, 95
257:
never mentioned any flash. What
Herodotus did write was that someone was accused of having arranged to "hold up a shield as a signal". Suspicion grew in the 1900s that the flash theory was implausible. The conclusion after testing the theory was "Nobody flashed a shield at the Battle of Marathon".
137:
campaign. It was very portable, did not require any power source, and was relatively secure since it was invisible to those not near the axis of operation, and the beam was very narrow, spreading only 50 ft (15 m) per 1 mi (1.6 km) of range. However, anyone in the beam with the
474:
In May 2012, "Solar Beacon" robotic mirrors designed at UC Berkeley were mounted on the towers of the Golden Gate bridge, and a web site set up where the public could schedule times for the mirrors to signal with sun-flashes, entering the time and their latitude, longitude and altitude. The solar
295:
of India. The Mance
Heliograph was operated easily by one man, and since it weighed about 7 lb (3.2 kg), the operator could readily carry the device and its tripod. The British Army tested the heliograph in India at a range of 35 mi (56 km) with favorable results. During the
356:
By 1887, heliographs in use included not only the
British Mance and Begbie heliographs, but also the American Grugan, Garner and Pursell heliographs. The Grugan and Pursell heliographs used shutters, and the others used movable mirrors operated by a finger key. The Mance, Grugan and Pursell
410:
In 1909, the use of heliography for forestry protection was introduced in the United States. By 1920 such use was widespread in the US and beginning in Canada, and the heliograph was regarded as "next to the telephone, the most useful communication device that is at present available for
181:
186:
184:
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work, and was suggested as a means of telegraphic communications. This is the first reliably documented heliographic device, despite much speculation about possible ancient incidents of sun-flash signalling, and the documented existence of other forms of
335:
had established a line of heliographs connecting Fort Keogh and Fort Custer, Montana, a distance of 140 mi (230 km). In 1886, General Nelson A. Miles set up a network of 27 heliograph stations in
Arizona and New Mexico during the hunt for
245:
were mirror flashes, but admitted "there are no references in ancient writings to the use of signaling by mirrors", and that the documented means of ancient long-range visual telecommunications was by beacon fires and beacon smoke, not mirrors.
132:
The heliograph had certain advantages. It allowed long-distance communication without a fixed infrastructure, though it could also be linked to make a fixed network extending for hundreds of miles, as in the fort-to-fort network used for the
150:. A good approximation for ranges of 20 to 50 mi (32 to 80 km) is that the flash of a circular mirror is visible to the naked eye at a distance of 10 mi (16 km) for each inch of mirror diameter, and farther with a
378:
in South Africa, where it was much used by both the
British and the Boers. The terrain and climate, as well as the nature of the campaign, made heliography a logical choice. For night communications, the British used some large
414:
Immediately prior to the outbreak of World War I, the cavalry regiments of the
Russian Imperial Army were still being trained in heliograph communications to augment the efficiency of their scouting and reporting roles. The
265:, High Sheriff of Buckinghamshire, England, notes: "Did this day heliograph intelligence from Dr Franklin in Paris to Wycombe". However, there is little evidence that "heliograph" here is other than a misspelling of "
445:
was the last major army to have the heliograph as an issue item. By the time the mirror instruments were retired, they were seldom used for signalling. However, as recently as the 1980s, heliographs were used by
383:, brought inland on railroad cars, and equipped with leaf-type shutters for keying a beam of light into dots and dashes. During the early stages of the war, the British garrisons were besieged in
411:
forest-protection services". D.P. Godwin of the US Forestry
Service invented a very portable (4.5 lb ) heliograph of the single-tripod, shutter plus mirror type for forestry use.
182:
1302:
92:. The flashes are produced by momentarily pivoting the mirror, or by interrupting the beam with a shutter. The heliograph was a simple but effective instrument for instantaneous
371: lb (6.3 kg) total weight, and ordered 100, for a total cost of $ 4,205. In 1893, the number of heliographs manufactured for the US Signal Service was 133.
1531:
Instruction Pratique Sur L'Installation des Communications Optiques dans le Service De la Telegraphie Militaire: Premiere Partie, Communications Optiques de Campagne
316:
heliography was often the only means of communication that could span ranges of as much as 100 mi (160 km) with a lightweight portable instrument.
1664:
279:(1840â1926), of the British Government Persian Gulf Telegraph Department, developed the first widely accepted heliograph about 1869 while stationed at
104:
work. Heliographs were standard issue in the British and Australian armies until the 1960s, and were used by the Pakistani army as late as 1975.
430:
During World War II, South African and Australian forces used the heliograph while fighting German forces in Libya and Egypt in 1941 and 1942.
1847:
648:
Google Books. Retrieved on 1 June 2008. pp. 160-181 are devoted to the heliograph, with diagrams of the British, American, and Godwin type.
1877:
1868:
1683:
478:
The first digitally controlled heliograph was designed and built in 2015. It was a semi-finalist in the Broadcom MASTERS competition.
170:, 183 mi (295 km) apart on September 17, 1894, with Signal Corps heliographs carrying mirrors only 8 in (52 cm).
1886:
Detailed photos of a British Mark V Heliograph and kit, links to patents. Clicking on visible photos reveals high resolution photos.
1748:
1325:
623:. Vol. III. Pamphlet No. 2. Heliograph, 5-inch, Mark V. 1922. London: His Majesty's Stationery Office. 1922. pp. 10â13.
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lines cut, the only contact with the outside world was via light-beam communication, helio by day, and Aldis lamps at night.
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and 125 mi (137, 142, 153 and 201 km) over a rugged and broken country, which was the stronghold of the
1927:
154:. The world record distance was established by a detachment of U.S. signal sergeants by the inter-operation of stations on
65:
1612:
2031:
1068:
916:
660:. Retrieved on 1 June 2008. Diagrams and instructions for British military heliograph (note British heraldry on cover).
579:
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during the Russian Civil War made use of a series of heliograph stations to disseminate intelligence efficiently about
1589:
1489:
1255:
775:
535:
308:
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12 in Ă 12 in (300 mm Ă 300 mm) heliographic signal mirror reflecting on the top of
2109:
122:
906:
269:". The term "heliograph" for solar telegraphy did not enter the English language until the 1870sâeven the word "
46:
1841:
943:
933:
838:
791:
765:
567:
525:
451:
1513:
1063:
Deacon, Richard (1978). The Silent War: a History of Western Naval Intelligence. David & Charles. p. 21.
225:) in 1821. His device directed a controlled beam of sunlight to a distant station to be used as a marker for
116:
Fig. 2: German heliograph made by R. Fuess in Berlin (on display at the Museum of Communication in Frankfurt)
889:
1356:
862:
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20:
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1965:
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until the 1940s, where it was considered a "low probability of intercept" type of communication. The
237:
For example, one author in 1919 chose to "hazard the theory" that the mainland signals Roman emperor
1850:
A description of the British Mance, Begbie and French LeSeurre heliographs with illustrations (1899)
2011:
1920:
1545:
384:
319:
2006:
493:
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222:
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over long distances during the late 19th and early 20th centuries. Its main uses were military,
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39:
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658:
Manual Of Instruction In Army Signaling 1886 Section III- Apparatus And Method Of Using It
8:
2104:
2041:
1913:
498:
1333:
863:"The Isle of Capri: An Imperial Residence and Probable Wireless Station of Ancient Rome"
2056:
1775:
1046:
1038:
1003:
995:
823:
752:
The Telegraph: A History of Morse's Invention and Its Predecessors in the United States
388:
300:
sent by the British-Indian government in 1877, the heliograph was first tested in war.
250:
191:
155:
1889:
1859:
1955:
1862:; 100+ historical heliograph photographs at the Australian War Memorial and elsewhere
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332:
226:
139:
1391:
An Improved Method in the Art of Signalling for Military and Scientific Purposes
1856:
Detailed color photographs of a World War 2 British Mance heliograph (Italian).
1620:
978:
Reynolds, P. K. Baillie (1929). "The Shield Signal at the Battle of Marathon".
490:, an early photographic process invented by Joseph Nicéphore Niépce around 1822
327:, where the Germans used to have a Heliographic Station (Bird's eye view, 2017)
202:
1204:
1136:
1034:
2093:
1894:
1883:
1415:
Annual Report of the Chief Signal Officer of the Army to the Secretary of War
1230:. Google Books. Retrieved on 2 June 2008. pp. 192-196 discuss the heliograph.
618:
442:
303:
288:
197:
602:
1905:
455:
438:
1853:
1975:
1829:
605:. Retrieved on 1 June 2008. Discussion of heliograph use in the Boer War.
504:
487:
447:
138:
correct knowledge could intercept signals without being detected. In the
80: 'to write') is a solar telegraph system that signals by flashes of
1326:"General Miles' Mirrors The Heliograph in the Geromino Campaign of 1886"
1042:
71:
2073:
1936:
770:. New York: The Mathematical Association of America. pp. 122â127.
380:
345:
270:
85:
999:
971:
603:
WIRE AT WAR - Signals communication in the South African War 1899â1902
30:
Fig. 1: Signaling with a Mance heliograph; Alaska-Canada border, 1910.
1684:"Solar Beacon atop Campanile allows for safe observation of sunlight"
965:
Herodotus, The Histories, with an English translation by A. D. Godley
434:
424:
396:
324:
266:
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206:
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97:
72:
53:
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Similarly, the story that a shield was used as a heliograph at the
238:
167:
134:
112:
81:
1866:
Royal Signals Datasheet No. 2. The Heliograph (revised April 2003)
1021:
Hodge, A. Trevor (2001). "Reflections on the Shield at Marathon".
341:
280:
19:
This article is about the signalling device. For other uses, see
125:
heliograph mirror did not tilt. This type produced flashes by a
2021:
2016:
1227:
Communications: An International History of the Formative Years
572:
Military Communications: From Ancient Times to the 21st Century
350:
89:
52:
26:
1665:"Golden Gate Bridge is prepared for 75th birthday celebration"
1394:, The American Helio-Telegraph and Signal Light Company, 1887
340:. In 1890, Major W.J. Volkmar of the US Army demonstrated in
242:
1844:
Photographs of British, American and Portuguese heliographs.
1638:
406:
British troops training with a heliograph; Egypt, June 1940
291:. Mance was familiar with heliotropes by their use for the
159:
1701:
1996:
1991:
1246:(1 ed.). Austin: University of Texas Press. p.
1895:
Signals communication in the South African War 1899-1902
1860:"Heliograph" at the National Library of Australia: Trove
673:. The Kipling Society website. Retrieved on 1 June 2008.
433:
The heliograph remained standard equipment for military
221:
developed and used a predecessor of the heliograph (the
935:
Marathon 490 BC: The First Persian Invasion Of Greece
894:. G.G. and J. Robinson, Paternoster-Row. p. 296.
646:
Methods of Communication Adapted to Forest Protection
1741:
331:
In the United States military, by mid-1878, Colonel
1528:
1564:"Ottoman Soldiers Mounting Signal Apparatus, 1917"
822:
1767:
1627:
2091:
644:W. N. Millar (1920), Canadian Forestry Service.
1694:
1193:Journal of the Royal United Service Institution
1125:Journal of the Royal United Service Institution
1658:
1656:
1613:"Ancient Heliograph Goes Modern for Space Age"
1537:
821:Holzmann, Gerard (1995). Björn Pehrson (ed.).
711:"On the Extinction of Light in the Atmosphere"
374:The heyday of the heliograph was probably the
1921:
1477:
1233:
1180:
1112:
715:Proceedings of the Royal Society of Edinburgh
1935:
1522:
1348:
613:
611:
253:is a modern myth, originating in the 1800s.
1715:
1653:
1604:
1505:
1189:"Heliography and Army Signalling Generally"
676:
561:
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555:
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1928:
1914:
1543:
1023:The Annual of the British School at Athens
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757:
640:
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636:
634:
632:
630:
1880:(PAGE 48 OF THE 1905 SIGNALLING HANDBOOK)
1610:
1518:(2nd ed.). Hachette. pp. 35â65.
1457:. Long Riders' Guild Press. p. 123.
1384:
1382:
1317:
1264:
1239:
1074:
958:
887:
754:. Google Books. Retrieved on 1 June 2008.
608:
1582:
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977:
820:
702:
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465:
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302:
196:
177:
111:
25:
16:Communication device reflecting sunlight
1842:Heliography: Communicating with Mirrors
1511:
931:
860:
854:
829:. IEEE Computer Society Press. p.
627:
523:
454:. Signal mirrors are still included in
323:Ruins of German Schutztruppe on top of
2092:
1675:
1406:
1379:
1354:
1121:"Mance's Heliograph, or Sun-Telegraph"
904:
767:Carl Friedrich Gauss: Titan of Science
746:
744:
742:
740:
738:
736:
663:
651:
597:
595:
593:
591:
1909:
1797:"2015 Broadcom MASTERS Semifinalists"
1749:"IPA Freshman's science fair project"
1270:
1218:
1186:
1118:
1080:
1020:
891:The Lives of the First Twelve Caesars
708:
565:
1721:
1681:
1243:The Lives of Frank and Alice Baldwin
1187:Wynne, Major A.S. (March 15, 1880).
1155:
129:mounted on a second tripod (Fig 4).
1546:"LA TĂLĂGRAPHIE OPTIQUE AUX ARMĂES"
1529:Charles-La Vauzelle, Henri (1912).
1481:Central Asia: Aspects of Transition
1471:
1357:"The Evolution of the Signal Corps"
1162:United Service Institution of India
1087:United Service Institution of India
961:"6.115.1, 6.121.1, 6.123.1,6.124,2"
733:
682:
588:
13:
1814:
1662:
1439:Report of the Chief Signal Officer
1271:Reade, Lt. Philip (January 1880).
825:The early history of data networks
570:. In Sterling, Christopher (ed.).
273:" was not coined until the 1790s.
14:
2121:
1890:The Heliograph in the Apache Wars
1835:
1773:
1682:Tuan, Lydia (10 September 2013).
1323:
1083:"The Heliograph or Sun Telegraph"
1081:Mance, Henry (10 February 1872).
938:. Osprey Publishing. p. 73.
353:and other hostile Indian tribes.
1902:at the Museum of RetroTechnology
1484:, Psychology Press, p. 20,
1442:. U.S. G.P.O. 1893. p. 671.
1355:Greely, Adolphus (August 1899).
911:. Yale University. p. 160.
867:The National Geographic Magazine
861:Kingman, John (September 1919).
802:(32): 255â256. September 7, 1822
1789:
1556:
1453:Littauer, Vladimir (May 2007).
1446:
1430:
1295:
1119:Goode, Samuel (June 14, 1875).
1057:
1014:
980:The Journal of Hellenic Studies
952:
925:
898:
881:
814:
784:
527:Wireless Optical Communications
261:In a letter dated 3 June 1778,
1313:(12578): 5. 20 September 1884.
517:
452:Soviet invasion of Afghanistan
107:
1:
2100:History of telecommunications
1590:"The Heliograph in Mauritius"
1158:"Army Signalling, Heliograph"
764:Dunnington, G. Waldo (2004).
709:Jacob, W.S. (November 1849).
510:
1822:Great Days of the Heliograph
1611:Pursglove, S. David (1961).
293:Great Trigonometrical Survey
7:
1570:. Ottoman Imperial Archives
1478:Everett-Heath, Tom (2003),
1156:Luck, George (1872-05-24).
967:. Harvard University Press.
481:
458:for emergency signaling to
21:Heliograph (disambiguation)
10:
2126:
1240:Steinbach, Robert (1989).
932:Sekunda, Nicholas (2002).
689:Signalling Handbook (1905)
232:ancient optical telegraphy
173:
64:
45:
18:
2030:
1984:
1966:Modulated continuous wave
1943:
1878:CHAPTER IV THE HELIOGRAPH
1544:BOUCHETHAL, J.L. (1916).
1205:10.1080/03071848009417153
1137:10.1080/03071847509415772
1035:10.1017/s0068245400005281
574:. ABC-CLIO. p. 208.
530:. John Wiley & Sons.
524:Bouchet, Olivier (2013).
2012:Morse code abbreviations
1937:International Morse code
1600:: 363. October 13, 1882.
1533:. pp. 30â32, 42â43.
568:"Heliograph and Mirrors"
298:Jowaki Afridi expedition
209:during World War I, 1917
61: 'sun' and
2007:Prosigns for Morse code
1884:Mance Mark V Heliograph
1512:Ternant, A.-L. (1884).
1174:2027/mdp.39015035103855
1099:2027/mdp.39015035103855
494:Heliotrope (instrument)
277:Henry Christopher Mance
219:University of Göttingen
2110:Optical communications
2079:Chinese telegraph code
1753:Island Pacific Academy
908:The Battle of Marathon
905:Krentz, Peter (2010).
566:Woods, Daniel (2008).
437:in the Australian and
407:
328:
312:
210:
194:
148:curvature of the Earth
117:
31:
2032:Other writing systems
1724:"Custom Show Setting"
1688:The Daily Californian
1617:Science and Mechanics
1418:, 1889, pp. 43â7
1307:Daily Alta California
466:Automated heliographs
405:
322:
306:
213:The German professor
200:
189:
115:
94:optical communication
29:
2002:Morse code mnemonics
1951:Electrical telegraph
1944:Transmission methods
1824:, Crown Point, 1987
1776:"Digital Heliograph"
1671:. Los Angeles Times.
1619:: 70. Archived from
1550:La Science et la Vie
1131:(LXXXIII): 534â548.
501:, a Scouting program
215:Carl Friedrich Gauss
2042:American Morse code
1336:on 17 February 2013
1303:"The Pacific Slope"
1273:"About Heliographs"
1224:R. W. Burns (2004)
986:(Part I): 100â105.
796:The Manchester Iris
601:Major J. D. Harris
499:Operation On-Target
423:rebel movements in
205:heliograph crew at
1871:2012-09-05 at the
1755:. 3 September 2015
1361:Ainslee's Magazine
1277:The United Service
959:Herodotus (1920).
888:Suetonius (1796).
450:forces during the
408:
329:
313:
251:Battle of Marathon
211:
195:
192:Mount Baden-Powell
118:
32:
2087:
2086:
1663:Boxall, Bettina.
1464:978-1-59048-256-8
669:Kipling, Rudyard
460:search and rescue
309:US Signal Service
285:Bombay Presidency
241:watched for from
187:
164:Mount Uncompahgre
123:U.S. Signal Corps
102:forest protection
88:) reflected by a
84:(generally using
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1923:
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1907:
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1805:
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1774:Welch, Natalie.
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1722:Vallerga, John.
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1637:. Archived from
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1625:
1624:
1623:on May 25, 2011.
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1399:
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1345:
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1341:
1332:. Archived from
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1268:
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949:
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902:
896:
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878:
876:
874:
858:
852:
851:
849:
847:
828:
818:
812:
811:
809:
807:
792:"The Heliotrope"
788:
782:
781:
761:
755:
748:
731:
730:
728:
726:
706:
700:
699:
697:
695:
685:"The Heliograph"
683:Signals, Royal.
680:
674:
671:A Code of Morals
667:
661:
655:
649:
642:
625:
624:
615:
606:
599:
586:
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563:
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541:
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370:
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311:heliograph, 1898
188:
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2125:
2124:
2120:
2119:
2118:
2116:
2115:
2114:
2090:
2089:
2088:
2083:
2052:Cyrillic script
2033:
2026:
1985:Notable signals
1980:
1961:Continuous wave
1939:
1934:
1873:Wayback Machine
1838:
1817:
1815:Further reading
1812:
1811:
1801:
1799:
1795:
1794:
1790:
1780:
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1772:
1768:
1758:
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1515:Les télégraphes
1510:
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1286:
1284:
1269:
1265:
1258:
1238:
1234:
1223:
1219:
1209:
1207:
1199:(CV): 235â258.
1185:
1181:
1154:
1150:
1141:
1139:
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1113:
1103:
1101:
1079:
1075:
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724:
722:
707:
703:
693:
691:
681:
677:
668:
664:
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628:
620:Signal Training
617:
616:
609:
600:
589:
582:
564:
545:
538:
522:
518:
513:
484:
468:
376:Second Boer War
367:
363:
360:
358:
333:Nelson A. Miles
227:geodetic survey
178:
176:
110:
24:
17:
12:
11:
5:
2123:
2113:
2112:
2107:
2102:
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2047:Greek alphabet
2044:
2038:
2036:
2028:
2027:
2025:
2024:
2019:
2014:
2009:
2004:
1999:
1994:
1988:
1986:
1982:
1981:
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1973:
1968:
1963:
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1947:
1945:
1941:
1940:
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1925:
1918:
1910:
1904:
1903:
1897:
1892:
1887:
1881:
1875:
1863:
1857:
1851:
1848:The Heliograph
1845:
1837:
1836:External links
1834:
1833:
1832:
1816:
1813:
1810:
1809:
1788:
1766:
1740:
1714:
1702:"Solar Beacon"
1693:
1674:
1652:
1641:on 30 May 2012
1635:"Solar Beacon"
1626:
1603:
1581:
1555:
1552:(28): 337â342.
1536:
1521:
1504:
1490:
1470:
1463:
1455:Russian Hussar
1445:
1429:
1405:
1378:
1347:
1324:Rolak, Bruno.
1316:
1294:
1263:
1256:
1232:
1217:
1179:
1168:(7): 101â105.
1148:
1111:
1093:(5): 123â130.
1073:
1069:978-0715375570
1056:
1013:
992:10.2307/625005
970:
951:
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924:
918:978-0300120851
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897:
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853:
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813:
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732:
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650:
626:
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587:
581:978-1851097326
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483:
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439:British armies
175:
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6:
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3:
2:
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2103:
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2098:
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2080:
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2069:Arabic script
2067:
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2064:Hebrew script
2062:
2058:
2055:
2054:
2053:
2050:
2048:
2045:
2043:
2040:
2039:
2037:
2035:
2034:in Morse code
2029:
2023:
2020:
2018:
2015:
2013:
2010:
2008:
2005:
2003:
2000:
1998:
1995:
1993:
1990:
1989:
1987:
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1956:Onâoff keying
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457:
456:survival kits
453:
449:
444:
443:Canadian Army
440:
436:
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310:
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289:British India
286:
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256:
252:
247:
244:
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235:
233:
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1781:6 September
1759:6 September
1707:7 September
1594:Engineering
1574:7 September
1029:: 237â259.
873:18 November
846:18 November
806:18 November
750:Coe, Lewis
505:Signal lamp
488:Heliography
381:Aldis lamps
263:John Norris
156:Mount Ellen
108:Description
2105:Telegraphy
2094:Categories
2074:Wabun code
1971:Heliograph
1142:2011-06-21
945:1841760005
840:0818667826
511:References
462:aircraft.
435:signallers
346:New Mexico
271:telegraphy
223:heliotrope
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38:(from
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425:Turkestan
397:telegraph
389:Ladysmith
385:Kimberley
325:Dikwillem
283:, in the
267:holograph
255:Herodotus
152:telescope
1869:Archived
1830:16902284
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1283:: 91â108
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1043:30073279
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482:See also
421:basmachi
417:Red Army
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338:Geronimo
307:Fig. 4:
239:Tiberius
168:Colorado
140:Boer War
135:Geronimo
82:sunlight
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2057:Russian
1733:28 June
1367:(1): 17
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1424:2008
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