## -4713 to 1967

-4713 | Julian datum. Counting days commenced. 01.01.1960 had | |||||

JD 2 436 935.00 astro. days | ||||||

-4200 | Babylonian year of 365 days | |||||

-4000 | Babylonian land title and law suits on clay tablets | |||||

-3800 | Babylonians used analog devices for surveying and map making | |||||

-3500 | Glass in Egypt | |||||

-3000 | Northern cubit a standard of length. Mesopotamia, Egypt, N Africa, India, China | |||||

-3000 | Egyptian river gauge called the Palermo stone. | |||||

-3000 | Egyptian world a rectangular box, Egypt in centre, sky was a flat or domed ceiling supported by columns or high mountains. | |||||

-2900 | Glass in Mesopotamia. A lens from Nineveh in Br. Museum | |||||

-2780 | Pyramids erected first at Gizeh by Cheops et al. Base perimeter = ½ geog. mile | |||||

-2600 | Egyptian standard of length on grey basalt column 53 cm long. | |||||

-2500 | Egyptian foot = ½ northern cubit = 13.2 inch. Egypt and Indus valley. | |||||

-2290 | Gudea, High priest shown on tablet holding a plane table on his knees. | |||||

Statue of Gidea in Louvre, shows Sumerian cubit = 30 fingers = 19.6 inch | ||||||

This standard used to set out Tower of Babel (Ziggurat of Ur). | ||||||

?? | Egyptian papyrus map of Nubian goldmines near Koptos. | |||||

-2000 | Crude lenses in Crete and coast of Asia Minor, made of rock crystal. | |||||

-2000 | Nine Chinese bronze vases depicted nine provinces + mountains, rivers etc | |||||

-2000 | Babylonians used astronomical phenomena for astrological purposes. | |||||

-2000 | Chaldeans divided day and night into 12 hours each. | |||||

Predicted eclipses, equator divided to 360º, named 12 signs of zodiac. | ||||||

-2000 | Mathematics for surveyors began with the triangle. | |||||

-2000 | Chinese algebra began | |||||

Greeks solved problems by geometrical means. | ||||||

Babylonians advanced into cubic and biquadratic equations. | ||||||

-2000 | Egyptian unequal hour shadow clock. | |||||

-1850 | Egyptian papyrus on geometrical problems. | |||||

-1850 | Babylonian clay tablet on survey problems. Contained threats to those | |||||

who might remove boundary stones. | ||||||

-1800 | Stonehenge erected. | |||||

-1800 | Pythagorean theorem | |||||

-1700 | Egypt- much practical geometry used in land surveying . | |||||

-1700 | Babylonia, Egypt. Computing area and volumes requiring fractions and pi. | |||||

-1550? | Egypt, Rhind papyrus describing mensuration, fractions, areas. | |||||

-1550 | Egyptian Royal Cubit of Amenhotep I. Now in Louvre. | |||||

-1500 | to -200. Chinese surveyors had plumbob, gnomon, water level, counting rods, hand computer, magnetic c ompass, square, groma. | |||||

-1450 | to -550. Many relics show Babylonian boundary surveys. | |||||

-15th C | Chinese daycount not dependent on sun or moon. Sexagesimal cycles. | |||||

-15th C | Clepsydra in Babylonia and Egypt. | |||||

-1400 | Text of the time of kurigalzu on ancient boundary stone. | |||||

-1400 | Egyptian tomb with pictures of sounding Nile with lead line. | |||||

-1361 | First record of lunar eclipse in China. | |||||

-1350 | Or -1220. Sacred cubit of Moses = 25 in. = Northern cubit. | |||||

-14th C | 28 lunar mansions = moon stations of zodiac in Chinese literature. | |||||

-13th C | Lunation of 29.53 days in China | |||||

-1250 | Ramses II (-1292t o -1225) instructed to erect tomb for a surveying engineer. | |||||

-1217 | First record of solar eclipse in China. | |||||

-12th C | Egypt. Simple and complex geometrical figures on urns etc | |||||

-1125 | Official topographic description of China by Wen-Wang. | |||||

-1000 | Or -600. Chinese jade work associated with circumpolar constellation templets. | |||||

Forerunners of the European nocturnal of +1150. | ||||||

-969 | Israel. Solomon built temple using Northern cubit (= 0.64 m) | |||||

-900 | To -500. Homeric Epics mention constellations Orion, Pleiades, Great Bear. | |||||

-800 | India. Sulvasutras- had chapter on setting out by ropes and rt. angled triangles. | |||||

-780 | China. Earthquakes recorded. | |||||

-750 | Hesiodos of Ascra recorded some astronomy. | |||||

-721 | Moon eclipse recorded by Babylonians | |||||

-715 | Hezekiah, 12th King of Judah, had water conduit of 1098 ft built in Jerusalem. Lateral breakthrough 20 ft. | |||||

-700 | Assyrian cubit on baked clay cylinder used to set out Khorsabad. | |||||

-672 | Chinese bronze mirrors. | |||||

-654 | Winter solstice in China- observed sun shadow with gnomon on tower. | |||||

-600 | Phoenicians used Little Bear for navigation. | |||||

-600 | Periandros of Greece contemplated canal through Isthmus of Corinth | |||||

-6th C | Theodorus of Samos had right-angle instruments | |||||

-6th C | China had decimal foot rules in bronze. Ten Chinese inches into tens | |||||

-6th C | Yang-Chheng gnomon 6 ft high, extant 1966. Shadow 1.5 ft at summer solstice | |||||

-6th C | Pythagoras and his disciples declared earth as a sphere. | |||||

Thales calculated heights of mountains from shadow length. | ||||||

Thales observed power of the magnet | ||||||

Glass made locally in China | ||||||

Pythagoras' theory on rays running from eye to object. | ||||||

-592 | Ezekiel described what he saw from top of a mountain - ie cadastral "map" | |||||

-575 | Sundials delivered from Babylonians or Chaldeans to Greeks. | |||||

-538 | Josua spent most of his life on cadastral surveys. Knotted cords | |||||

-532 | Philolaos discussed rotation of planets including sun around "fire". | |||||

-500 | Babylonians expressed large numbers in multiples of 60. | |||||

Chinese large numbers in multiples of 10. | ||||||

Romans expressed larger numbers in multiples of 12 or 16. | ||||||

Democritus - formula for volume of pyramid. | ||||||

- to + 1300. Development of cosmological theories. | ||||||

Aristagoras - maps on bronze and iron tablets | ||||||

Babylonian world map on clay tablet. | ||||||

-5th C | Antiphon, calculus to measure magnitudes of exhaustion. | |||||

Herodotus attributed beginning of geometry to annual overflow of R Nile. | ||||||

He described aquaduct / tunnel on Samos. | ||||||

-480 | Greece - 6 mile canal through Mt Athos peninsula. | |||||

-475 | Parmenides "moon shines with reflected light". | |||||

-450 | Heracleides - geocentric system of planets. Some round sun, others about earth. | |||||

Earth rotated about its own axis. | ||||||

-408 | Eudoxus explained maths of celestial motions. 27 spheres. | |||||

-400 | First armillary rings in China. 1464 stars in Chinese catalogue. | |||||

-400 | China. Mohists proposed standardisation of length measure. | |||||

-400 | Indian method of meridian determination in Surya Siddhanta. | |||||

Romans attempted orientation of temples, tombs, cities etc. | ||||||

-4th C | Chou Pei Suan Ching publication on maths and astronomy. | |||||

Water level to get horz. surface for sun shadow. Meridian from sun rise and set. | ||||||

-4th C | Studies on vision. Refraction. Reflection. refractive index etc | |||||

-4th C | Heaven likened to Hen's egg, earth to yolk. Circ. 365¼º | |||||

Shih Shen's and other star catalogues including Hipparchos. | ||||||

China. Heaven has 9 layers. Distance to sky 20000 li = 6000 km | ||||||

Sun illuminates 167000 li diameter (= 50000 km) | ||||||

Theophrastus and Eudemos wrote histories on cosmography and early astro. | ||||||

Dikaearchos (-350--290) idea of reference line to orient maps. Ran W - E | ||||||

-384 | Aristotle increased Eudoxus spheres to 55. Concluded earth a sphere. | |||||

-350 | Menaechmos, rectangular coord axes. Maybe founder of analytical geometry. | |||||

-330 | Theoretical geometry applied to physical science by Mohist Canon Mo Ching. | |||||

Mention of carpenter's square. | ||||||

-313 | onwards. Romans built Aqua Appia. See quote Werner Calendar p 10 | |||||

-312 | Aristarchos postulated heliocentric system of planets. Defined ecliptic. | |||||

Rotation of earth about own axis. Angle between sun and half moon = 87º | ||||||

really 89º 51'. Distance sun-earth 19 x dist. moon-earth. Should be 389 times | ||||||

-300 | Euclid's 15 vol. on mathematics, especially geometry. | |||||

-300 | Greeks. Complex analogs of solar system | |||||

-300 | Start of 500 year domination of Univ. of Alexandria in scientific life. | |||||

-300 | Indian world map allowed China 1/81 of world surface. | |||||

-3rd C | Apollonius used coordinate axes. | |||||

-3rd C | Eratosthenes size of earth Alexandria - Syene. | |||||

-3rd C | China. Minute appreciation of topographic features. | |||||

-3rd C | Ctesibius refined clepsydra with float. | |||||

-3rd C | to + 6th C. Chinese cosmology- heavens a spherical dome, earth an upturned | |||||

bowl. Distance between domes 80000 li | ||||||

-290 | to -212. Archimedes staff with flat disc held to cover sun. | |||||

-290 | Archimedes solved problems of calculus, analytical and differential geometry | |||||

-284 | Eratosthenes suggested coordinate grid over a spherical earth. | |||||

Fundamental parallel through Rhodes and meridian thro' Syene, Alexandria etc | ||||||

Lu Pu-Wei assumed earth as flat disc. | ||||||

-270 | Eudoxus' work made known through Phenomena and Prognostica. | |||||

-270 | Berossos. Inverted hemisphere known as a scaphe. | |||||

-260 | Aristarchos. Tangent ratio in right angles. | |||||

-250 | Time by hour glass | |||||

-250 | Chinese astronomers and mathematicians defined pi 3.14159 | |||||

-250 | Timosthenes of Rhodes. Sea charts with distances between harbours | |||||

-240 | Halley's comet of +1682 first recorded in China. | |||||

-240 | China. Hodometer -drum carriage to count miles. | |||||

-227 | First record of Chinese silk map carried in a wooden box to hide a dagger. | |||||

-210 | Chinese relief model of R. Yangtze. | |||||

-207 | Emperor Chhin Shih Huang-Ti collected Empire maps. | |||||

-200 | Registration of boundaries of areas travelled by Chinese emperors. | |||||

-200 | China. 2 ten ft gnomon 1000 li apart N-S. Shadow decreased 1 inch per 1000 li | |||||

-200 | Four cardinal points fixed. Data determined for a calendar. | |||||

-200 | Appollonius introduced epicycles. | |||||

-2nd C | Chinese used negative numbers | |||||

-190 | to -125. Hipparchos eccentricty of earth orbit 1/24 RE (really 1/60 RE). | |||||

Year as 365d 5h 55m (really 49m). Invented? astrolabe. | ||||||

-177 | Persia. Seleucid Greeks constructed tunnels marked by line of well shafts. | |||||

c -150 | Heron's dioptra for areas, inaccessible heights etc | |||||

He described standardisation of measuring ropes. Water level and staff. | ||||||

-150 | Crates. Suggested representing earth as globe divided to 4 equal continents. | |||||

-140 | Hipparchus used terms mekos and platos - longitude and latitude. | |||||

-140 | Seleucos studied tides in Persian Gulf. | |||||

-140 | Hipparchus. Graphical solution of spherical triangles. | |||||

-130 | Hipparchos introduced term climata for area between parallels. | |||||

-120 | Chinese gnomon up to 40 ft high. | |||||

-120 | China. Chuang-Hsiung-Phi built Dragon Head canal with shafts and tunnels. | |||||

Used metal sighting tube for distance. Water level. Compass. Plumb line. | ||||||

-104 | Sundials in China with plate inclined in equatorial plane, gnomon pointing at the pole. Some dials with centesimal graduation. | |||||

-1st C | Posidonius distancs sun-earth 13000 RE (actually 23400) | |||||

-1st C | Caesar planned complete survey of empire. Responsible for Roman roads and aquaducts in Italy, France, Germany etc. | |||||

-1st C | Posidonius gave meridian quadrant as 11000 km | |||||

-100 | Egypt. Edfu temple has erroneous inscription on area of quadrilateral. | |||||

-90 | Historical record of Chinese astronomy written by Ssuma Chhien. | |||||

-60 | Nero's engineers began Corinth canal. Abandoned for fear of diff in levels | |||||

-52 | Chinese permanently fixed equatorial ring on armillary. | |||||

-50 | Large clepsydra in Tower of Winds, Athens | |||||

-46 | Calendar troubles. Last year before commencement of Julian calendar | |||||

lasted 445 days. Sosigenes prepared new work. | ||||||

-15 | Vitruvius reported on automatic timepiece- Horologium anaphoricum- had astrolabe disc with a net of projected parallels and meridians. Water driven. | |||||

+4 | Boundary line in Wurttemberg 80 km long.Resurveyed 1911. Out of | |||||

alignment by 2 m in 29 km. | ||||||

+5 | China. Chia Liang Hu by Liu Hsin, a model to define standard measures. | |||||

pre +7 | Balbus constructed right angle with aid of a semi-circle. | |||||

18 | Roman wall map | |||||

32 | Relief maps modelled in rice. | |||||

60 | Apostle Paul report on sounding lines | |||||

69 | Diviner's board with compass indications, symbolic rep. of heaven and earth. | |||||

80 | Wang Chhung discussed dependence of sea tides on moon. | |||||

83 | China. First self-registering direction finder. | |||||

84 | China. Ecliptic armillary ring. | |||||

89 | Chia Khuei, precise definition of ecliptic. | |||||

1st C | Fort Caburn, Sussex set out with Sumerian ft of 20 shusi as standard. | |||||

1st C | Cinerarium in Vatican Gardens portrayed in relief the Roman ft measure. | |||||

1st C | Difference between Greek and Chinese mathematics | |||||

1st C | Geocentric system of planets. | |||||

100 | Chang Heng scientific cartography in China used rectangular grid. | |||||

100 | Menelaos wrote Spherics containing the sine function. | |||||

100 | China. South pointing carriage. | |||||

100 | Heron's De Speculis on mirrors and angle of reflection. | |||||

105 | Mechanical process of paper making from plant fibres. | |||||

107 | South pointers frequently mentioned - lodestone; wet and dry models | |||||

120 | Ptolemy insisted maps to be based on astro. obs. Longitude in terms of time coords. and not guesses. Lats by transits of circumpolar stars. | |||||

120 | Chinese Pan Ku and Pan Chao used coordinate system | |||||

125 | Horizon and meridian rings added to Chinese armilleries. | |||||

130 | Chinese star catalogue of 2500 stars + 11250 smaaler ones counted. | |||||

150 | Ptolemaic chord tables. First mention of abacus by Hsu Yo. | |||||

164 | Gnomon shadow template of jade | |||||

178 | China. Calendar reform. Ideas on obliquity similar to Eratosthenes. | |||||

190 | Shu Shu Chi-I mention of calendrical astronomy. | |||||

2nd C | Anti-Kythera machine. Anaphoric clocks in Hellene. | |||||

200 | China. Hydrographic record. Marine navigation. | |||||

200 | China. Cosmology of infinite empty space. | |||||

230 | Chao Ta, dial and pointer system for direction finding. | |||||

250 | Indirect height measurement. | |||||

263 | Chinese text on measuring heights and distances with poles bearing crossbars. | |||||

265? | Precession of equinoxes by Yu Hsi (or 320?) | |||||

267 | China. Levelling. Measuring curves and straights to reduce for slope. | |||||

275 | Diophantus called negative numbers absurd. | |||||

3rd C | Chinese calculus. Roman abacus. Celestial globe. | |||||

3rd C | Ref. to crosswire grid. Length standards for small distances based on | |||||

diameter of silk thread = 1 hu. | ||||||

330 | Pytheus travelled Europe et al reporting on tides and other topics. | |||||

4th C | Magnetic needles in China | |||||

4th C | First Chinese star map. | |||||

400 | Indians produced modern trigonometry as Paulisa Siddhanta. | |||||

445 | Ho Chheng-Thien simultaneous obs. at Hanoi and Hue gave decrease in shadow with latitude of 3.56 in per 1000 li. | |||||

450 | Chinese wood relief 10 ft square. | |||||

475 | Indeterminate analysis in China. | |||||

480 | Pi to 3.1415929203 by Tsu Chhung-Chih. Finite differences in astronomy. | |||||

5th C | Marcellus and Pliny the Elder reported on repellant force of lodestone. | |||||

500 | Li Tau-Nguan commented on hydrography in China in 40 volumes. | |||||

500 | Chang Chiu-Chien noted survey problems using right angled triangles. | |||||

505 | Varaha-Mihira used sines and c osines. | |||||

510 | Aryabhata gave name sinus to that function. Tables x 1 degree | |||||

540 | Cassiodoros reported on science of land surveying. | |||||

548 | Multiplication tables by Li Nien. | |||||

570 | Chinese computations by abacus. | |||||

6th C | Arabs created terms zenith, nadir, azimuth. | |||||

6th C | Arabs determined obliquity of the ecliptic. | |||||

600 | Seismograph by Lin. | |||||

604 | Liu Chhuo selected baselines in flat country along meridian through | |||||

Honan and Hopei to determine time by clepsydra and to set gnomons. | ||||||

632 | Astro. obs. tower in Korea about 30 ft high. Use a pin hole to determine | |||||

shadow length to 3 dec. places of a foot. | ||||||

640 | Arabs observed stars with 20 ft quadrant and 56 ft stone sextant at Abul Welfa. | |||||

Some obs. in connection with geodetic baselines. | ||||||

646 | China. Schools of surveying established. | |||||

Japanese emperor pordered production of cadastral maps. | ||||||

7th C | Codex Arcerianus (Irish) described survey practice and legal aspects. | |||||

7th C | European churches oriented N. | |||||

7th C | China. Magnetic declination discovered. | |||||

7th C | Japanese used south indicator. | |||||

7th C | Balance arm clepsydra at Antioch. | |||||

713 | Mechanical clockwork in China. | |||||

713 | to 800. Terrestrial civil unit fixed as 1/351 Chinese degree. | |||||

716 | Original Arabian foot shown on column. The Nilometer. | |||||

718 | Indian sine tables traslated into Chinese | |||||

721 | to 725. Eleven Chinese obs. points on line through Hue (not on same meridian) | |||||

Hue 17.9ºN Weichow 40ºN. Diff. shadow lengths 4 in/ 1000 li. | ||||||

723 | Clockwork escapement invented in China. | |||||

725 | I-Hsing. Armillary spheres with ecliptically mounted sighting tubes. | |||||

777 | Al-Fazari under Al-Masur made first Arabic astrolabe. | |||||

Arabian plumb bob recorded at that time. | ||||||

8th C | Arabs used carpenter's s quare (Kunija) larger than a groma. | |||||

8th C | Significance of metric system recognised in China. | |||||

Attempts to define terrestrial units in terms of astro. or geodetic constants. | ||||||

800 | Windroses developed by Vikings. | |||||

800 | Arabian manuscript on astrolabes. | |||||

820 | Al-Kwarizmi developed Hindu number system and algebra. | |||||

Text on algebra in which the word was invented. | ||||||

827 | Arabs measured baselines near Baghdad. | |||||

840 | Camera obscura in China. | |||||

850 | Arabs mechanised papermaking. | |||||

850 | Al-Battani added the shadow square to the astrolabe. | |||||

871 | Alfred the Great determined inch as 3 grains of barley, dry, round. | |||||

9th C | Arabs rejected earth rotation about own axis. | |||||

900 | Ibn Jabir ibn Sinan al Baltani concept of tan and cotan. | |||||

950 | Gerbert conveyed Muslim surveying knowledge to the West. | |||||

970 | Abul-Wafa al-Buzjani concept of secant and cosecant. | |||||

975 | King Edgar ordained 3 ft = 1 yard. | |||||

992 | Decimal system for weight became official in China. | |||||

10th C | Sighting tube reported in a codex of St Gallen monastery. | |||||

1000 | Hamid Ibn al Khidr al-Khujandi sextant radius 57 ft. | |||||

1080 | Chinese maps, reasonably accurate, at 1:31 680 | |||||

1086 | Shen Kua, enguineer and surveyor, determined lengths of arcs and | |||||

produced tables on chords and arcs. Arc = chord + S.S/R (S= mid ordinate. He also set out canals, slopes, levelling dams etc by water level. | ||||||

1090 | Su Sung's astronomical clock tower 35 ft high. Powerdriven globe and | |||||

armillary sphere. Latter had a sighting tube. | ||||||

11th C | Arabs, decimal fractions from Indians, transmission to Jewish and | |||||

Latin scholars in 12th C. | ||||||

11th C | Length of year known to Mayas Incas and Indians as 365.2420 | |||||

1103 | Chinese sighting tube for altitude. | |||||

1114 | Indian horizontal staff described by Bhaskara. Used by Muslims to measure depth of wells. | |||||

1120 | Henry I, statute on standard yard. Hexagonal brass yard. | |||||

1137 | Two Chinese maps carved in stone had grid to scale of 100 li. | |||||

1150 | Jabir ibn Aflah probable inventor of Torquetum. | |||||

Recording of star altitudes by finger width of outstretched arm. | ||||||

1155 | First printed Chinese map | |||||

1159 | Arab cylindrical sundial | |||||

1180 | Alexander Neckam described magnetic needle in De naturis rerum. | |||||

1198 | Chinese Astronomer Royal severely punished for wrongly predicting solar eclipse by ½ day. | |||||

12th C | China. Timekeeping by metal incense clock, burning point of powder | |||||

winding through labyrinth of characters. | ||||||

12th C | Determination of diameter and circumference of a circular walled city from afar. | |||||

1200 | Venetian glass makers developed art of lens making. | |||||

1205 | Seven day week introduced in China. | |||||

1220 | Fibonacci analytical geometry in Europe. | |||||

1229 | Translation of Arab writings on astronomy. | |||||

1232 | Floating compass needle used in Persia. | |||||

1247 | Chinese planisphere engraved in stone. | |||||

1250 | Alfonsine tables of planets | |||||

1258 | Nasir al-Din al-Tusi first Director of Observatory at Maragha. | |||||

Al-Tusi 12 ft wooden mural quadrant with sights, copper limb to degrees. | ||||||

1269 | Peregrinus described azimuthal dial with alidade and compass. | |||||

1274 | Zero number in Chinese computations. | |||||

1276 | Chinese gnomon 40 ft high in brick tower at Yang-chheng, 120 ft shadow scale and waterchannel for level control. | |||||

1276 | Torquetum by Kuo-Shou-Ching in Peking. | |||||

1279 | Kuo Shou-Ching's observatory at Peking. | |||||

1285 | Spina and Armati invented spectacles. | |||||

13th C | Bacon studied properties of mirrors and plano convex lenses. | |||||

13th C | Al-Urdi al-Dimashqi improved ancient Indian circles method for Azimuth fixes. | |||||

13th C | al-Marrekushi's 134 geog coords froim astrofixes. | |||||

13th C | Bowl compass in Chinese waters for navigation. | |||||

13th C | Seismograph at Maraghah Observatory | |||||

13th C | to 17th C England. Open field system. Unit length, reach of a barge pole. | |||||

13th C | Jacob staff by Levi ben Gershon. | |||||

13th C | Decimal point by Yang Hui. | |||||

1300 | Chu Ssu-Pen atlas of China. | |||||

1305 | Edward I, unit of length 1 inch of 3 grains of barley. | |||||

1306 | Grid map of Palestine. by Sanuto. | |||||

1311 | Portolan charts with rectangular grids by Pietro. | |||||

1335 | Gough map of England with 3 different miles- 2230 yard in England; 2250 yard in Wales;' 2800 yard in Cheshire. | |||||

1350 | Gough's Itinerary map of Gt Britain. | |||||

Relief map of Gibraltar by Ibn Battutah | ||||||

1370 | Oresme used terms longitudo, latitudo. | |||||

14th C | Chinese road alignments by compass. | |||||

14th C | First European mechanical astronomical clocks. | |||||

1416 | Henry the Navigator founded School of Navigation in Sagres. | |||||

1421 | Polish topographical map. | |||||

1437 | Ulug Beg Star Almanac. Had quadrant 180 ft high for star obs. | |||||

1440 | Gutenberg invented letterpress. Maps mainly cut in wood. | |||||

1462 | Sea quadrant by de Cintra. | |||||

1471 | Diaz rounded Cape of Good Hope. | |||||

1472 | Ivan the Terrible established unique library under the Kremlin. | |||||

1473 | Zacuto published perpetual almanac in Hebrew. | |||||

1477 | Intaglio printing by Durer. | |||||

1492 | Behaim's Nurnberg globe with prime meridian 2º W of Canary Is. | |||||

1493 | Pope Alexander VI divided map of world in two by meridian in mid Atlantic. | |||||

1493 | Columbus discovered discrepancy between Flemish and Italian compasses. | |||||

1496 | Bronze rod yard standard in Britain. | |||||

1497 | Vasco da Gama sailed to India. | |||||

15th C | Purbach geometric square . Tables of sines and tangents. | |||||

15th C | de Cusa supported heliocentric theory and diurnal rotation of earth. | |||||

15th C | L da Vinci - Visible masses on the earth's surface are in equilibrium. | |||||

1500 | Organum viatorum. Pocket size combination of compass + sundial | |||||

1507 | Copernicus wrote De revolutionibus orbium coelestium. | |||||

1508 | Portable clock in Europe | |||||

1512 | Waldseemuller's polimetrum for bearings and altitudes. | |||||

1512 | Evidence of nautical cartography in Java | |||||

1513 | Piri Rei of Turkey, sea chart of Atlantic with American Coast. | |||||

1523 | Fitzherbert. First book on surveying; Boke of Surveyinge. | |||||

1524 | Tartaglia box compass with altitude on circular graduated board. | |||||

1525 | French topographical maps by Fine and Coline | |||||

1525 | Russian topographic maps made by invited foreigners. | |||||

1525 | Guillen combined gnomon and compass for variations in magnetic declination. | |||||

1525 | Fernel measured distance Paris-Amiens by carriage wheel. | |||||

1528 | Topographic maps in Russia and Poland by Wapowski. | |||||

1530 | Term chronometer suggested by Frisius. | |||||

1530 | Agricola wrote De re metallica on mine surveying | |||||

1530 | Arsenius added a compass to an astrolabe. | |||||

1533 | Frisius wrote on triangulation. | |||||

1534 | Frisius portable equatorial armillary sphere. | |||||

1537 | de Benese wrote The Boke of Measuringe Lande. | |||||

Distance by wooden rod of 1 perch = 5½ yards long. | ||||||

1537 | Nunez designed the nonius for reading quadrants. | |||||

1540 | Quality woodcut map of Bavaria by Apian. | |||||

1541 | Box compass by Neudorfer | |||||

1542 | Differential quadrant by Rotz for navigation. Simul: det: lat and Az. | |||||

1542 | Hartmann discovered inclination of magnetic needle. | |||||

1545 | Marine Jacob's staff by de Medina | |||||

1546 | Tartaglia reported on survey methods in Italy. | |||||

1546 | Brahe designed 19 ft quadrant for his Danish observatory. | |||||

1546 | Mercator recognised existence of magnetic poles. | |||||

1547 | Ryff improvement of theodolite | |||||

1550 | De Roja's book on astrolabium published. | |||||

1551 | Foulon with plane table plus holometre. | |||||

1551 | Munster designed trigonus- three straight rods in triangle vide triquetum | |||||

1554 | Mohit used Jacob staff with various sliding plates for star altitudes. | |||||

1556 | King Akbar decreed 25 Indus inch = 1 gaz (= the Ilahi gaz or Akbar yard) | |||||

1556 | Digges Tectonicon | |||||

1557 | Modern = sign by Recorde | |||||

1559 | Cunningham described triangulation | |||||

1564 | Bartoli different design of polimetrum | |||||

1569 | Mercator true bearing chart for navigators. | |||||

1569 | Rheticus taught proper survey control for mapping. | |||||

1570 | World map by Ortelius | |||||

1571 | Theodolitus by Digges. Also the instrument topographicall | |||||

1571 | Torquetum by Regiomontanus | |||||

1571 | Kepler succeeded Brahe in Prague. | |||||

1574 | Gutmann wrote Felsmessen,gewiss.richtig und kurz gestellt. (On proper | |||||

survey methods). | ||||||

1574 | Reinhold similar book to Gutmann. Preferred a wire to hemp cord for distance. | |||||

1579 | Brahe connected Denmark and Sweden via Oresund. | |||||

1579 | Saxton's English county maps with triangulation control | |||||

1581 | Galilei observed swinging chandelier | |||||

1583 | Ricci world map with flattened sphere projection. | |||||

1585 | Decimal arithmetic introduced by Stevin. | |||||

1587 | Sea charts by Mercator son Rumold. | |||||

1588 | Q Elizabeth I St. yard of 36 inch = 3 ft.......1760 yds to mile | |||||

1590 | First Italian telescope by Porta. | |||||

1593 | Chinese reel of measuring tape similar to modern | |||||

1594 | Hulsius elaborate quadrant with compass sundial | |||||

1594 | Praetorius ball and socket head for plane table tripod. | |||||

1594 | Errard de Bar-le-Duc telemetre | |||||

1594 | Werner's Jakob staff 7 ft long with 2000 divisions for angle measure | |||||

1595 | Davis back staff for use at sea. | |||||

1597 | French astrolabe - graphometre by Danfrie. | |||||

1598 | de Subermille designed Henry metre- a combination of rods. | |||||

1598 | Pfintzing surveyors carriage with dial recording hodometer | |||||

16th C | Hommel (1518-1562) Leipzig, promoted surveying. | |||||

16th C | Seven European astro instruments with 360º divs. reached China via Persia. | |||||

16th C | Leonard and Thomas Digges experimented with telescope making. | |||||

1600 | Decimal division. 1 chain = 100 links | |||||

Germany. Miner's Lachter-Kette or brass chain was 8-12 m long. | ||||||

1600 | X sign introduced by Viete | |||||

1600 | Pitiscus published his Trigonometriae | |||||

1600 | Clavius wrote Operum Mathematicorum. | |||||

1605 | Topographic map of Japan. | |||||

1606 | Snellius described compass declination of 11º 15' | |||||

1607 | First 6 of the 15 books of Euclid translated into Chinese by Ricci. | |||||

1607 | Logarithms by Burgi. | |||||

1608 | Dutch trunks (telescopes) by Lippershey. | |||||

1609 | First two of Kepler's Laws published. | |||||

1610 | Kepler's astronomical telescope for surveyors. Huygens refined lens making. | |||||

1610 | Galilei observed Jupiter with 30X telescope. His sector for computations. | |||||

1610 | French toise marked by iron rod in foot of stairs of Le Chatelet. | |||||

1612 | Word telescope used by Lagalla but ascribed to Demisiani | |||||

1612 | Harriot went as surveyor to Virginia. | |||||

1612 | Scheiner's helioscope. | |||||

1612 | Dou's Holland circle made in Amsterdam. It had a cross swivel joint tripod. | |||||

1612 | Word telescope used by Lagalla. | |||||

1614 | Napier's addit. logs and natural functions. | |||||

1615 | Snellius introduced base extension and resection into triangulation. | |||||

Used large 4 or 5 ft diam copper quadrant with transversal to 1'. | ||||||

1615 | Kepler's Doliometria described vol. calculations by prismoidal rule. | |||||

1615 | Dias in China mentioned telescope in his Explanation of the Celestial Sphere. | |||||

1616 | Rathborne's The Surveyor. Described theodelite, playne table, circumferentor. | |||||

1617 | Napier's bones. | |||||

1618 | First telescope arrived in China. | |||||

1619 | Third law of Kepler published. | |||||

1620 | Introduction of slide rule | |||||

1621 | Snellius' sine law of refraction | |||||

1622 | Oughtred invented straight log. slide rule. | |||||

1624 | Briggs logs to base 10 | |||||

1624 | Log slide rule by Gunter | |||||

1624 | Gunter's Description and Use of the Sector... published. | |||||

1626 | Chinese book on telescopes. | |||||

1627 | Wingate's straight edge slide rule. Two scales. | |||||

1630 | Bleau alleged to have measured base between Maas and Texel. | |||||

1630 | Algebraic geometry by Gethaldi. | |||||

1631 | Vernier designed. | |||||

1632 | Oughtred described a circular slide rule. | |||||

1633 | Norwood's measure London to York by chain. What else? | |||||

1636 | Mersenne's reflecting telescope. | |||||

1637 | Descartes work on lenses. | |||||

1637 | Descartes cartesian analytical geometry and integral exponents. | |||||

1638 | Telescopes fitted with cross hairs of silk by Gascoigne. | |||||

1639 | Gascoigne's movable hair in telescope. Hence gradienter method. | |||||

1640 | Gascoigne's knife edge eyepiece micrometer. | |||||

1640 | Adding machine suggested by Ciermans. (Scierman) | |||||

1640 | Theory of numbers and analytical geometry by Fermat. | |||||

1640 | Leibniz coined terms abscissa and ordinata. | |||||

1642 | Pascal's adding machine. | |||||

1642 | Torricelli had idea of mercury barometer | |||||

1643 | Viviani experimented on making a vacuum. | |||||

1644 | Mersenne observed free fall acc due to gravity by pendulum | |||||

1645 | Riccioli & Grimaldi arc measure Mt Serra-Paderno-Modena. Unreliable. | |||||

1647 | Hevelius' 150 ft long telescope. Pub. Selenographia and Machinae coelestis | |||||

1648 | Pascal's Lunar tables. | |||||

1648 | Pascal taught use of barometer for height difference with Torricelli barometer | |||||

1650 | Divini and Campani made long focus object glasses. | |||||

1650 | De La Hire suggested engraving cross hairs by diamond. | |||||

1650 | Gilbert considered earth as a large magnet. | |||||

1650 | First use of logs in China. | |||||

1650 | Partridge modern slide rule with movable centrepiece. | |||||

1653 | Improvement of level by Strumienski of Cracow | |||||

1653 | Claramontius improved level. | |||||

1653 | Leybourn published his The Compleat Surveyor. Went to 5 Edns by 1722 | |||||

1654 | Barometric measures demonstrated to the Regensburg Reichstag. | |||||

1654 | Jakob Bernouilli started his work on catenary, loxodrome, spirals etc | |||||

1657 | Huygens grandfather clock. | |||||

1658 | Atwell published his The Faithful Surveyor. | |||||

1658 | Hooke's spiral spring for pocket watches. | |||||

1659 | Huygens and Hooke micrometer designs. Intro of virgula = tapered metal bar and hair micrometer | |||||

1660 | Italian level with floating gunsights by Schoff | |||||

1660 | Division sign introduced | |||||

1660 | Tilas of Sweden- mining compass | |||||

1660 | Picard - semi-automatic levels. One with telescope and water level container other with plumb bob forcing telescope into horizontal position. | |||||

1660 | Chinese obtained slide rule from Europe. | |||||

1660 | Mouton suggested an unalterable universal measure for the metre. | |||||

1661 | Thevonet invented spirit bubble. | |||||

1662 | Van Breen (Holland) improved nautical staff with coloured observer's glass | |||||

1662 | Reticule micrometer with several silver wires by Malvasia. | |||||

1663 | Gregory - two mirror combination for reflecting telescope proposed | |||||

1665 | Newton postulated earth as oblate spheroid. | |||||

1666 | Newton clarified distinction between spherical and chromatic aberration. | |||||

1666 | Foundation of Academie des Sciences, Paris. | |||||

1666 | Auzout filar micrometer. | |||||

1667 | Praetorius wrote on diving rods in Gazophylaci gaudium. | |||||

1667 | to 1670. Picard, Auzout and Romer established precision astronomy. | |||||

1667 | Godunov's first map of Siberia | |||||

1668 | Hooke's shortened telescope and lens grinding machine. | |||||

1668 | Newton's reflecting telescope. | |||||

1669 | Riccioli and Picard observed free fall acc due to gravity by pendulum | |||||

1669 | Chains in use- Rathborne 1 perch = 100 links; Gunter 4 perches or poles = 100 links | |||||

1669 | Verbiest reequippoed Peking astronomical observatory. | |||||

1669 | to 70. Picard determined arc from Amiens to Malvoisin | |||||

His quadrant used on arc was 10 ft radius with telescopic sights and cross hairs | ||||||

1670 | and on. Newton and law of gravitation. | |||||

1670 | Differential calculus by Leibniz, Briggs, Napier and Newton | |||||

1670 | to 90. Observatories built in Paris, Greenwich and Berlin. | |||||

1670 | Hooke suggested clockwork driven telescope. | |||||

1670 | Mouton proposed a linear scale based on a geodetic minute. | |||||

1671 | Picard suggested a Universal Foot as function of sec pendulum | |||||

1672 | Cassegrain suggested reflecting telescope | |||||

1672 | to 1695. Leibniz Staffelwalzenmachine for multiplication and tens transmission | |||||

1672 | Richer in Cayenne observed parallax to Mars | |||||

Noticed that his pendulum had to be shortened at Cayenne to keep time. | ||||||

1672 | G D Cassini I determined distance earth-sun. | |||||

1673 | Hooke and Hevelius compared merits of gunsights with telescope pointing. | |||||

1673 | Loevenhoek showed great skill in lens grinding. | |||||

1674 | Montanari used stadia method for distance. | |||||

1677 | Foster in Boston USA First American map in woodcut. | |||||

1677 | Flamsteed equatorial sextant. Wrote Historia Coelestis. | |||||

1682 | Pendulum observations by Halley, Varin, Deshayes, de Glos and Goree. | |||||

1683 | Seki Kowa wrote on determinants. | |||||

1683 | Cassini I extended Picard's arc north to Dunkirk | |||||

1683 | Cassini II wrote on barometric levelling. | |||||

1684 | Romer's transit instrument at Copenhagen. | |||||

1686 | Halley deduced crude relation for pressure v height | |||||

1686 | to 1743 Maharajah Jai Sing set up over 40 astro. instruments in various cities. | |||||

1687 | Hooke suggested a Pole finding telescope with concentric circles. | |||||

1687 | Newton wrote Philosophiae naturalis principia mathematica. | |||||

1688 | Chinese scholar gave details of ancient Chinese standards of length. | |||||

1693 | Leibniz wrote on determinants | |||||

1697 | Contour lines introduced by Ancelin, Rotterdam | |||||

17 C | Leybourn published method of closing traverses. | |||||

17 C | Beginning of modern Geodesy | |||||

17 C | Jesuits arrived in China.They had a cosmos of the closed Ptolemaic-Aristotelian geocentric universe of solid concentric crystalline spheres. This opposed the doctrine of the floating of heavenly bodies of Hsuan-Yeh. | |||||

17 C | Roman Catholic & Protestant clergy supplied "all round" geodesists to Europe. | |||||

eg Cusa, Copernicus, Picard, Boscovich, Bohnenburger. | ||||||

1700 | La Hire began extension of Picard arc to the south. | |||||

It reached Colliure by 1716 or 18. gave prolate figure !! See entry p 46 | ||||||

1700 | Halley's charts of magnetic declination across continents and oceans. | |||||

1700 | Newton designed first octant. He wrote on ancient metrology. | |||||

1702 | Leibniz had idea of using elastic deformation of metal for pressure measure. | |||||

1702 | Antoine Thomas arc measure in China. See entry p 46 | |||||

1702 | Mallet described spirit levels. | |||||

1704 | Romer's meridian circle. | |||||

1704 | Le Blon experimented on colour effects in printing. | |||||

1705 | Sherwin 7 figure log tables. | |||||

1707 | to 1717. Complete resurvey of China by Jesuits. | |||||

1707 | Euler started teaching in Basel, Petersburg and then Berlin. | |||||

1708 | to 12. Hooke and Flamsteed used van Breen's ideas on the quadrant. | |||||

1709 | Bion described octagonal surveyor's cross for 45º and 90º horz. angles. | |||||

1710 | Peter the Great (Russia) ordered linear scale (fuss) supposedly equivalent | |||||

to ancient Chinese foot, to be made equal to English foot. | ||||||

1713 | Bernouill binomial distribution. | |||||

1714 | Board of Longitude offered £20000 for solution to longitude. | |||||

1720 | Halley succeeded Flamsteed as Director Greenwich Observatory | |||||

1720 | Cassini proposed a geodetic ft = 1 terrestrial minute of arc | |||||

1721 | Hadley reflecting telescope 200X Mag 6 ft long | |||||

1723 | La Hire. Level instrument with floating gun sights. | |||||

1724 | Burgh (Dublin) used double meridian distance to compute areas. | |||||

1725 | New observatory in Japan. Accepted Copernican system. | |||||

1726 | Petersburg Acad.Sc.founded by Peter the Great. | |||||

1727 | Bradley aberration of stars idea conceived. | |||||

1730 | Sisson making theodolites with micrometers. | |||||

1731 | Godfrey's sea quadrant. (USA) | |||||

1732 | Hadley's octant reading to 1 min arc. | |||||

1732 | George Washington born | |||||

1733 | De Moivre's normal distribution. | |||||

1733 | Herschel introduced reflecting telescope used in today's 1" theodolites. | |||||

1733 | Cassini began parallel arc measure St Malo to Strasbourg. | |||||

1734 | Publication of first Russian Atlas. | |||||

1735 | Start of Peru arc expedition. Used Toise de Perou. | |||||

1735 | La Condamine observed free fall acc due to gravity by pendulum | |||||

1735 | to 7 La Condamine, Godin and Bouguer found length equat: secs pendulum | |||||

1735 | Invariable pendulum by Mairan used by Maupertuis at Pello 1736 | |||||

1735-42 | French arc by Maupertuis in Lapland. See p 50 for details | |||||

1736 | Bouguer at foot of Chimborazo to experiment of deflection of vertical. | |||||

1736 | Six Roman linear standards on tablet in Rome measured by Folkes of Roy.Soc. | |||||

1737 | De L'isle measured base on ice Petersburg to Cronstadt. | |||||

1737 | Clairaut, Maclaurin proved Newton's law of gravitation. | |||||

1737 | Clairaut proved Newton's hypothesis of oblate earth. | |||||

1737 | Leigh - sextant with artificial fluid horizon | |||||

1738 | French Acad. announced that Cassini prolate earth had been rejected. | |||||

1739 | to 40. C F Cassini III, and Lacaille repeated earlier Cassini II arc measure. | |||||

1739 | to 40. Cassini and LaCaille resurveyed Picard arc and added 5 bases. | |||||

1740 | Age of scientific instrument makers began with Langlois | |||||

1740 | Celcius discovered short period variations of magnetic declinations. | |||||

His temperature scale used. | ||||||

1742 | Bradley succeeded Halley as Director Greenwich Observatory. | |||||

1742 | Roy.Soc.organised manufacture of Yard measure based on Elizabeth's of 1588 | |||||

1742 | Results from Peru expedition- oblate earth. | |||||

1743 | Clairaut published Theorie de la Figure de la terre. See p 52 | |||||

1743 | pendulum. | |||||

1744 | Cassini de Thury IV began Carte topographique de la France | |||||

1744 | to 99. Triangulation linking Greenwich and Paris. | |||||

1745 | C F Cassini's (III) transversal cylindrical projection. | |||||

1747 | Murdoch Mackenzie's hydrographic surveys of Orkneys. | |||||

1747 | to 1803. Survey of British Isles. | |||||

1747 | La Condamine proposed length equatorial secs pendulum as standard. | |||||

1748 | Bradley described nutation. | |||||

1749 | Faye found free air reduction of g. | |||||

1749 | D'Alembert proved Bradley theory of precession | |||||

1750 | La Caille catalogued 10 000 stars at Capetown in two years. | |||||

1750 | to 69. Arc measure of Liesganig, Varasdin-Brno. | |||||

1750 | Meridian arc Rome - Rimini by Boscovich and Meyer. | |||||

1750 | Stuart and Revett measured Parthenon. | |||||

1750 | Chezy internal grinding of spirit level vials. | |||||

1750 | Naime, London. Manufacturing barometers, thermometers etc | |||||

1750 | Boscovich compensation theory of crustal masses. | |||||

1751 | to 1753. La Caille arc in S Africa. | |||||

1757 | Marine chart of English Channel by Buache (France) Or 1737. See R107p141 | |||||

1758 | Bird made a standard for Parliamentary committee | |||||

1758 | Cook charted St Lawrence river. | |||||

1758 | Breithaupt - hanging theodolite. | |||||

1759 | to 60. Beccaria arc in Piemont near Turin. | |||||

1759 | Chinese azimuth compass in gimbal mounting for use at sea. | |||||

1761 | Cassini III began parallel arc Brest to Vienna | |||||

1762 | Ramsden opened workshop in London. | |||||

1763 | Harrison and Leroy. First ship chronometer. | |||||

1764 | Brander theodolite maker. | |||||

1764 | Osterwald used a wooden bridge to support measuring rods on Bavarian base | |||||

1764 | to 68. Mason-Dixon arc measure. Wooden box-type rods | |||||

1765 | Meyer's widow received payment for his lunar tables. | |||||

1766 | Louis XIV edict on Toise de Perou. | |||||

1767 | Bird wrote The Method of Dividing Astronomical Instruments. | |||||

1767 | Maskelyne- first nautical almanac | |||||

1769 | Transit of Venus. | |||||

1770 | to 83. Guinand (Swiss) worked on improving flint glass. | |||||

1770 | Mayer suggested to Ramsden using his dividing engine for full circles | |||||

1770 | Hahn (G) -first reliable and durable calculating machines, different sizes. | |||||

1770 | Mining Academies established Berlin, Pribram (CZ), Sopron (Hun), Petersburg | |||||

1771 | Watts stadia tacheometry | |||||

1772 | Lambert's conic projection | |||||

1772 | Radcliffe observatory founded in Oxford. Since 1948 has been in S Africa | |||||

1773 | Adams artificial horizon for sextant. | |||||

1774 | Maskelyne and Hutton plummet method for g, Mt Schehallien. | |||||

1774 | Harrison finally got his reward for chronometer. | |||||

1775 | to 77. Ramsden constructed dividing engine. | |||||

1775 | Mining Acad. established in Clausthal inHasrz Mts. | |||||

1775 | to 83. Introduction of 4 screw theods in USA | |||||

1778 | Green inserted a micrometer in the eyepiece | |||||

1780 | French weavers used punch cards. Jacquard of Lyons | |||||

1782 | Troughton Bros took over Rowley old shop. | |||||

1783 | Muller calculator | |||||

1783 | Roy began triangulation in England. | |||||

1784 | Roy base on Hounslow Heath with glass rods. | |||||

1784 | Prony produced 17 vols of Tables du Cadastre with logs nat. figs to 14 decs. 1 - 200 000. Used centesimal angular division. | |||||

1785 | Theodolite by Ramsden | |||||

1785 | Boscovich observed free fall acc due to gravity by pendulum | |||||

1785 | Borda's repeating circle with two telescopes. | |||||

1785 | Remeasure Hounslow base by Williams, Mudge andDalby. | |||||

1785 | Rittenhouse used spider webs as cross hairs | |||||

1787 | Ramsden made 3 ft diameter circle to 1 sec by micrometer. | |||||

His direction theodolite | ||||||

1787 | French instrument makers (Fortin etc) formed a corporation. | |||||

1787 | Channel crossing by triangulation. Roy, Cassini,Legendre and Mechain | |||||

1787 | Legendre's solution of fundamental geodetic triangle computation | |||||

1789 | Sir John R Miller raised the decimal question in House of Commons. | |||||

1790 | 400g to circle introduced in France, S Germany and Switzerland. | |||||

1790 | French repetition theodolite | |||||

1790 | Cary apprentice under Ramsden. | |||||

1790 | Metric committee in France. Borda, Condorcet,Lagrange, Laplace,Monge | |||||

1790 | Borda et al expressed planetary distances in earth radii; need for R value | |||||

Suggested quadrant as 10 000 000 m | ||||||

1790 | Barrow meridian arc lat 23º 18' | |||||

1790 | Talleyrand proposed length of secs. pendulum as a unit of length. | |||||

1791 | Fr. Decimal Committee recommended 1/10M of quadrant as a metre. | |||||

1791 | Longitude and horary graphs for mariners. | |||||

1791 | Borda and Cassini IV pendulum obs at Paris Observatory. | |||||

1791 | First contour maps in France. | |||||

1791 | French baselines by 30 ft firwood rods. | |||||

1791 | to 99 Br Admiralty Hydrographer, Hurd, charted Bermuda. | |||||

1791 | OS of Great Britain founded. | |||||

1792 | Sawitch flattening from pendulum obs. | |||||

1792 | to 99 Delambre and Mechain arc in France as part solution to metre value. | |||||

1792 | 22 September. French Republic established. | |||||

1793 | Third Report by Decimal Committee. 1 prov. m = 443.44 P Lines. | |||||

1794 | Vega, Nautical Almanac, also log. slide rule replacing Galilei sector. | |||||

1795 | Metric system legalised in France. | |||||

1796 | Czar Paul instituted the Dépot of Maps. | |||||

1797 | Dallabella,Lisbon, inverse square law of magnetic force. | |||||

1798 | Cavendish determined earth density. His torsion balance. | |||||

1798 | Napoleon's officers discovered the nilometer on Elephant Is in the Nile. | |||||

1798 | Mechain & Delambre submitted their results. | |||||

1799 | Prototype legal metre in France. | |||||

1799 | Delambre published Methodes analytiques pour la determination ....meridien. | |||||

18 C | English scientists used French pied du roi of 144 Paris lines (=325 mm). | |||||

18 C | Horrebow-Talcott latitude method. | |||||

c1800 | Lehmann (1765-1811) put shape of hachures on a mathematical basis. | |||||

1800 | Munich becoming centre of continental instrument making. | |||||

1800 | Senefelder introduced flatbed on stone block and offset printing | |||||

1801 | Depot General de la Guerre began production of Carte de la Baviere. | |||||

1801 | Paris parallel arc begun. Strassburg-Munich. | |||||

1801 | Svanberg reobserved Lapland arc of Maupertuis. | |||||

1802 | Flinders hydrographic surveys of Gulf of Carpenteria. | |||||

1802 | Laplace proved Mayer correct (1765) and added term to moon latitude equation. | |||||

Hence reversed process and found earth flattening. | ||||||

1802 | to3 Laplace derivation of pressure-height relationship. | |||||

1802 | von Zach & von Muffling baseline for Thuringian triag. near Gotha. | |||||

Terminal points as cannons set vertically. First used by Roy in 1791 | ||||||

1802 | to 1822. Triangulation began in India. | |||||

1804 | Repetition theodolite by Reichenbach. | |||||

1804 | Sacharof and Robertson balloon ascent from St Petersburg. | |||||

1804 | Mechain proposed extension of French arc to Balearic Is. | |||||

1804 | Mechain died in despair at errors in astro. lat of Barcelona. See p 60 | |||||

1804 | to 1811. Lambton parallel arc through Madras | |||||

1805 | Legendre applied least squares to French arc of 1792. See p 60 | |||||

1805 | Senefelder invented zincography | |||||

1806 | Legendre- length of a geodesic. | |||||

1806 | to 08. Biot and Arago extended French arc to Formentera on Balearic Is. | |||||

Arago wrote about it in his Historie de ma jeunesse. | ||||||

1806 | Illig. In papermaking, replaced animal glue by resin or alum. | |||||

1807 | Hassler founded US Coast & Geodetic Survey. | |||||

1807 | Arago suggested use of sound to measure depths. | |||||

1808 | Gauss astrolabe. Simultaneous determination of lat. and long. | |||||

1808 | to 25. Biot, Mathieu, theory of mathematical pendulum. | |||||

1810 | Soldner replaced plane rect. coords. by spherical rect. coords. | |||||

1810 | Senefelder invented transfer printing. | |||||

1810 | Review of French arc measures revealed short comings. | |||||

Napoleon refused permission to re survey Lapland arc. | ||||||

1811 | Mechanical press by Konig. | |||||

1811 | Laplace induced French to survey parallel arc of Marennes to Fiume (Istria) | |||||

Interrupted by war of 1813-14. | ||||||

1811 | Bohnenberger suggested an inverted (reversible) pendulum | |||||

1812 | French troops noticed an English built transit in Moscow and saved it | |||||

from the big fire lit by Russians in self defence. | ||||||

1812 | Pond catalogue of polar distances of 43 stars. | |||||

1814 | Stern calculator | |||||

1814 | First survey ships on British Navy list | |||||

1814 | Planimeter by Herman. | |||||

1815 | Triangulation in Italy. | |||||

1816 | Start of Struve triangulation. | |||||

1816 | to 17. First US baseline by Hassler at Tinively Valley. | |||||

Second base on Long Island. | ||||||

1817 | Struve initiated his meridian arc | |||||

1817 | Kater reversible pendulum. Suggested by Prony 1792 & Bohnenberger 1811 | |||||

1818 | Laplace published Theorie analytique des probabilités | |||||

1818 | Brousseaud & Nicollet observed Brest to Strasbourg on parallel of Paris. | |||||

1819 | Bohnenberger gyroscopic theory and construction of his precession machine. | |||||

1819 | Young's modulus of elasticity | |||||

1820 | Fraunhofer engraved cross hairs by diamond. | |||||

1820 | Thomas (F) Arithmometer | |||||

1820 | Struve baseline near Dorpat. | |||||

1820 | Schumacher baseline in Holstein | |||||

1820 | Gauss used heliotrope on Hanover arc. | |||||

1820 | to 24; and 1838-53. Complete triangulation of Great Britain. | |||||

1820 | Topographic survey began in Russia under Schubert | |||||

1821 | Carline and Plana recomputed Beccaria's arc. | |||||

1821 | Carlini deflection of plumb line at Mt Cenis | |||||

1821 | Gauss triangulation and arc measure adjusted by least squares. | |||||

1821 | to 22. Carlini and Plana filled gap between Alps and Turin in arc of Marennes. | |||||

Rockets or powder signals for simult. obs. for longitudes. | ||||||

1822 | Babbage Difference machine. | |||||

1822 | Fitzroy on Beagle in Sydney to determine longitude of Parramatta Obsy. | |||||

1822 | Parramatta observatory established by Sir Thomas Brisbane. | |||||

1822 | Memphis cubit rod (pre Rameses I) found at Jomar. | |||||

1823 | Bonne baseline at Brest for parallel arc | |||||

1823 | to 28. 30 000 miles of African coast charted by Owen. | |||||

1824 | First standard yard reached Sydney | |||||

1825 | Bessel refined Kater pendulum | |||||

1825 | Parallel arc Munich to Budapest | |||||

1825 | India confirmed the 1556 Akbar yard of 33 E Inch = 25 Indus inch | |||||

= the Indian yard. | ||||||

1826 | OS of Ireland begun by Colby. | |||||

1826 | Drummond invented heliostat and limelight. | |||||

1826 | Troughton and Simms partnership in instrument making. | |||||

1826 | Niepce photoengraving = photo intaglio | |||||

1826 | Oldendorps planimeter | |||||

1827 | Colby surveys | |||||

1827 | Babinet suggested light wave as natural unit of length | |||||

1827 | math. figure of earth in terms of geometric measurements. | |||||

1828 | Schmidt compuation of Hannover triangulation. To Gauss instructions. | |||||

1828 | Bohnenberger used spherical coordinates. | |||||

1828 | to 32. Map of nineteen counties by Thomas Mitchell, Australia | |||||

1828 | Ramsden 10 ft rod arrived in Sydney to standardise chains. | |||||

1829 | Cooke began instrument making career | |||||

1829 | Russian triangulation connected to Konigsberg observatory. Hence parallel arc England-France-Prussia-Russia. | |||||

1830 | Prussia took lead in geodesy from S Germany. | |||||

Foundation of Trigonometrische Abteilung des Preuss. | ||||||

1831 | to 41. Bessel triangulation in E Prussia. | |||||

1832 | to 33. Henderson further meridian arc obs. CapeTown. | |||||

Related computations by Olufsen, Breen and Stone. | ||||||

1832 | Everest baseline at Calcutta using Colby apparatus. | |||||

1832 | Hengler horizontal pendulum for deflection of plumbline. | |||||

1833 | Poisson work on seismic waves. | |||||

1833 | Stokes formula for distance between geoid and spheroid. | |||||

1834 | Jacobi triaxial ellipsoid. Followed by Clarke and Schubert. | |||||

1834 | Baeyer and Bessel on Prussian oblique arc. Base at Trenk | |||||

1834 | to 48. Babbage analytical engine. | |||||

1835 | Gauss and Weber fundamental study of geomagnetism | |||||

1836 | Mayer idea tpo determine eccentricty of ellipsoid by triang. of skew meridian | |||||

1837 | Poisson distribution. See p 48 for other names. | |||||

1838 | First astronomical observatory in USA at Williamstown. | |||||

1839 | Daguerre-Niepce reproduction of pictures by photographic emulsion. | |||||

1839 | Bessel toise. | |||||

1840 | Bessel spheroidal formulae | |||||

1840 | Blondat rubber hose over 50 m for hydrostatic levelling | |||||

1840 | Weisbach triangle in mine surveying | |||||

1840 | Everest theodolite, Indian subtense bar. | |||||

1840 | Precise traversing heads for mine survey by Breithaupt Kassel | |||||

1840 | to 80. S Australian triangulation included 7 bases. see Frome on Surveying. | |||||

1841 | Talbot developed photographic negative | |||||

1841 | Puissant discovered error of 68t in distance Formentera-Montjouy | |||||

1841 | to 78. Great Lakes triangulation USA suffered from bad base. (Sacle) | |||||

1841 | Everest base at Bidar by Colby bars. | |||||

1842 | J F Herschel discovered method of sun printing in blue | |||||

1842 | Ertel level with stadia hairs and horizontal circle | |||||

1843 | Chesterman cloth tape reinforced by wire. | |||||

1843 | Sumner, USA used position lines | |||||

1844 | Struve obtained permission to extend his arc to Tornea | |||||

1844 | Belgian triangulation using broken ray technique. | |||||

1844 | Chambers log tables | |||||

1845 | Staffel of Warsaw. Calculator | |||||

1845 | Stampfer discussed precision of pointing in relation to target shape | |||||

1846 | to1902. USCGS arc measures | |||||

1847 | to 56. Parallel arc Astrachan-Kishinev | |||||

1848 | to 56. Brest-Tchernowitz parallel arc observed. Extended to 20º by Wrochenko. | |||||

1848 | Many Laplace stns around Moscow by Schweizer. | |||||

1848 | Maclear remeasure of La Caille arc in S Africa. | |||||

1848 | Roche density of the earth | |||||

1849 | Maurel & Jayet (F) calculator | |||||

1849 | Kellner compound eyepiece. | |||||

1849 | Stokes on variation of gravity at surface of earth | |||||

1849 | Laussedat architectural photographs for measurements. | |||||

1850 | Vidie, Bourdon and Schinz independently invented metal capsule barometer | |||||

1850 | Foucault pendulum used to prove rotation of earth. | |||||

1850 | Reichenbach perfected his stadia hair method | |||||

1850 | -51. Le Gray and Archer. Photographic plates | |||||

1851 | Airy transit circle installed at Greenwich | |||||

1852 | Struve arc extended by Tenner towards Murmansk and Danube estuary. | |||||

1852 | Stampfer optical plumbing in mines. | |||||

1853 | Oppert found Assyrian ft standard at Babylon to be 329 mm for 30 shusi | |||||

1853 | Porro anallactic lens | |||||

1853 | -58. Porro, Koppe & Meydenbaur developed principles of photogrammetry. | |||||

1854 | Amsler polar planimeter | |||||

1854 | Airyu flotation theory of earth crust. | |||||

1855 | Alum lithoplates by Poitevin | |||||

1855 | Balloon photography in Paris by Nadar alias Tournachon | |||||

and in Boston, USA and Solferino, Italy | ||||||

1855 | Pratt observed deflection of plumbline in Himalayas. | |||||

1855 | Levelling used to determine settlement for first time. Near Stuttgart. | |||||

1856 | Stokes theory of physical pendulum | |||||

1857 | Parallel arc from Valencia (Eire) to Orsk suggested by Struve | |||||

1858 | Error or standard ellipse by Andrae. | |||||

1858 | Anaglyphic stereoscopic viewing by d'Almada | |||||

1858 | -59. Bertaud objective + Brunner camera box + theodolite for contours by photo. | |||||

1859 | to 77.Spanish triangulation. Connected to N Africa at Laghouat, Algiers | |||||

1859 | Schubert computed tri-axial ellipsoid | |||||

1859 | Eckholdt omnimeter measured a tangent ratio by screw. | |||||

1859 | Amsler reversible level. | |||||

1860 | Hayford clarified concepts of isostasy. | |||||

1860 | Triangulation England-France. Clarke computed arc and again in 1866 and 1880 | |||||

1860 | Base in Victoria, Australia 5½ miles long. Took 9 months | |||||

1860 | in 1876-7. On to Tunisia in 1884-5 | |||||

1860 | -80. Andrae, Sonderhof & Helmert discussed lateral refraction. | |||||

1860 | Sir Wm Thompson (Lord Kelvin) pressure tube for water depths. | |||||

1861 | Bessel ideas on reversible pendulum constructed by Lohmeier of Hamburg. | |||||

1861 | Norwegian geodetic commission formed | |||||

1861 | Gen Baeyer plan of international cooperation in geodesy. Became IUGG | |||||

1861 | -72. Central European parallel arc from Haverford to Orsk. | |||||

1861 | Third connection England-France. Others 1787 and 1822 | |||||

1863 | Kelvin theory of tides of earth crust. | |||||

1863 | Hoskold put plane mirror in front of theodolite for optical plumbing. | |||||

1864 | First meeting of IUGG | |||||

1864 | Baselines at terminals of Norwegian Trig. Christiana and Rinderleret. | |||||

1865 | Italian geodetic commission formed. | |||||

1865 | Precise levelling in Saxony by Nagel and Prussia and Bavaria in 1867 | |||||

1865 | Pujo fundamentals of photogrammetry | |||||

1866 | Villarceau general formula of Laplace equation. | |||||

1866 | Clarke computed triaxial ellipsoid | |||||

1866 | Hydrographic Office of U S Navy formed. | |||||

1866 | Von Wullerstorf idea of aneroid for relative gravimetry. | |||||

1867 | Spain, Portugal and Russia join IUGG | |||||

1867 | Precise levelling with Breithaupt instruments in Berlin. | |||||

1868 | New S Wales. Baselines at Lake George and Richmond. | |||||

1868 | Helmert worked on error ellipse | |||||

1868 | Villarceau and Bruns computations of geoid. | |||||

1868 | Creation of Prussian Geodetic Institute in Berlin. | |||||

1869 | Zollner horizontal pendulum | |||||

1869 | -70. Viertel, theodolite + eccentric telescope set vertical by autocollimation. | |||||

1870 | Helmert became Director of Zentral Bureau der Int. Erdmessung in Berlin. | |||||

1870 | Gauss five figure log tables. | |||||

1870 | -88. Revision of French arc Perpignan-Melun. Used Brunner theodolites. | |||||

1871 | Maddox photogelatine printing, dry plates. | |||||

1871 | Jordan optical plummet by refracting line of sight from 45 deg. mirror. | |||||

1871 | Brunner baseline equipment for European work | |||||

1871 | -98. Arc measure on 39th parallel in USA from Atlantic to Pacific | |||||

Ten baselines | ||||||

1871 | Thin, 66 ft, tape of crinoline steel introduced in Australia. | |||||

1872 | Barrel type calculating machine with toothed wheel. By Baldwin, USA | |||||

1872 | Schreiber test of circle graduations | |||||

1873 | Nagel designed and constructed theodolite for optical plumbing. | |||||

1873 | Jordan, Finsterwalder mapping from photographs. | |||||

1873 | Colour photography by Vogel, Clark Ducos du Hauron. After idea by Maxwell 1857 | |||||

1873 | Listing introduced tem Geoid | |||||

1873 | Todhunter book on History of Theory... published. | |||||

1873 | 10 Laplace stations in Harz mountains. | |||||

1874 | Transit of Venus in NSW | |||||

1874 | Hansen testing line scales. | |||||

1874 | New International metre standard deposited at Paris. | |||||

1875 | Marc St Hilaire dead reckoning for position lines. | |||||

1875 | 18 countries sign Treaty in Paris to establish Int.Bur.of Wts and Measures | |||||

1875 | Helmert method of accuracy of graduation of horizontal circles. | |||||

1875 | Peirce, USA determined vibration (or flexure) of pendulum support. | |||||

1876 | Algiers parallel reached Kap Bon and Sicily | |||||

1876 | Helmert defined line of sight in telescopes | |||||

1876 | Zacharie (Denmark) rectangular spherical computations. | |||||

1876 | Lord Kelvin harmonic analyser for tidal prediction. | |||||

1877 | Photogravure printing | |||||

1878 | Ohdner calculating machine. | |||||

1878 | Couturier reflection level with suspended telescope. | |||||

1879 | Ibanez and Perrier observed quad across Mediterranean to join French arc to N African parallel. | |||||

1879 | German level datum in Berlin connected to Amsterdam gauge. | |||||

1879 | Geoid map of Central Asia by Fergana | |||||

1880 | Nagel-Hildebrand optical plummet on interchangeable traverse heads. | |||||

1880 | Forster, Eggert, Broun, increase of visual acuity by coincidence method | |||||

1880 | Hollerith punch cards with electrical switch feeler | |||||

1880 | Von Sterneck pendulum with coincidence apparatus. | |||||

1880 | Term nomograph coined by D'Ocagne | |||||

1880 | Jaderin introduced new baseline technique with thin steel wires. | |||||

1881 | Mendenhall deflection of vertical at Mt Fujiyama | |||||

1881 | Offset printing by Champenois | |||||

1882 | Free swinging plumb bobs used in German shaft plumbing | |||||

1883 | Harmonic analysis of tides by G H Darwin and J C Adams | |||||

1883 | Longitude connection Singapore-Darwin-Sydney by Barrachi & Darwin | |||||

1883 | First geoid maps of Harz by Andrae | |||||

1883 | Fergola suggested Int. latitude service | |||||

1883 | -91. Queensland triangulation | |||||

1884 | Helmert dynamic correction | |||||

1884 | Great Britain joined Metric Convention | |||||

1884 | -90. Development of several types of camera including photo-theo.by Paganini | |||||

1885 | Algiers parallel reached Tunisia | |||||

1885 | Report from Berlin on 14 differing toise scales unsed in Europe Triangulation. | |||||

1886 | Scholz worked on error ellipse | |||||

1887 | Lallemand- orthometric correction | |||||

1887 | -92. Michelson and later Benoit determined number of red waves in cadmium | |||||

in one metre. | ||||||

1888 | Lorenzoni, Italy, determined vibration (or flexure) of pendulum support. | |||||

1888 | Penrose measured the Parthenon in Athens. | |||||

1888 | Introduction of terrestrial photogrammetry by Deville, Canada | |||||

1888 | -96. Eotvos torsion balance for gravity components | |||||

1889 | Bllee calculating machine | |||||

1889 | Austrian, French and German officers mapped Greece. | |||||

1889 | More countries join IUGG | |||||

1889 | Barr and Stroud glass wedge for optical distance measurement. | |||||

1889 | Dutton coined term isostasy | |||||

1889 | -93. Various experiments with horizontal pendulum | |||||

1890 | Rotogravure by Klie | |||||

1890 | Algraphy= aluminium sheet printing by Scholz, Mullaly and Bullock (1891). | |||||

1890 | Fennel, Kassel theodolite with in built optical plummet | |||||

1890 | -03. Precise levelling Kronstadt - Black Sea -Sea of Azov | |||||

1890 | -35. Triangulation Brest - Astrachan | |||||

1890 | De Grousilliers suggested to Zeiss idea of stereophotogrammetry | |||||

1891 | Chile, Peru covered with triangulation | |||||

1892 | Brunsvega twin desk calculator | |||||

1892 | French physicists introduce wavelength method to define the metre | |||||

1892 | Pulfrich constructed a rangefinder with floating mark (of Stolze) | |||||

1892 | -10. First geodetic levelling of Finland. | |||||

1893 | Three colour process by Kurtz | |||||

1893 | -98. Diagram tacheometer by Poncagli, Urbani and Hammer. Italy. | |||||

1894 | Double image optical distance measurement. Richards USA | |||||

1894 | Guilleaume suggested use of hypsometer with mercury barometer for g at sea | |||||

1895 | First stereo plotter by Machand, Deville in Canada | |||||

1895 | Relief printing mechanical press | |||||

1896 | Guilleaume developed invar for survey tapes. | |||||

1896 | Finsterwalder and Hugerhoff phototheodolite. | |||||

1896 | Geoidal profiles computed in Berlin | |||||

1896 | -03. Work of Scheimpflug on photogrammetry | |||||

1896 | -06. Helmert experiment on fluctuation of equipotential surface. | |||||

1897 | Russian Engineers used photos to locate railways near Chinese borders | |||||

1897 | Act of Parliament in GR to legalise metric system | |||||

1898 | Russian-Swedish expedition to Spitzbergen. Used Jaderin wires | |||||

1898 | Hildebrand optical plummet for nadir and zenith plumbing | |||||

1898 | -05. Four metre subtense bar used in German E Africa | |||||

1899 | Austrian Marine obs of refraction at sea horizon | |||||

19 C | Turkey mapped by Austrian Military surveyors | |||||

19 C | Bulgaria mapped by Russian officers | |||||

c1900 | 1400 absolute gravity stations observed. Used to adjust Helmert formula | |||||

1900 | Kites with combined cameras used in Moscow by Thiele. | |||||

1901 | Geoid map of Switzerland by Messerschmitt | |||||

1901 | Stereocomparator by Abbe, Pulfrich and Zeiss. | |||||

1902 | Helmert work on spheroidal formulae | |||||

1902 | Invar staves used for precise levelling in Europe. | |||||

1902 | -06. Reobservation of Peru arc. See p 76. | |||||

1902 | -09. Hayford ellipsoid. Also topo.-isostatic reduction formula. | |||||

1903 | First geoid map of US East coast by USCGS | |||||

1903 | Double point resection by Finsterwalder | |||||

1904 | Albrecht test to determine long. diff. Potsdam-Brocken Mt by wireless | |||||

in comparison with telegraphic transmission. | ||||||

1904 | Absolute gravity observed at Dehra Dun | |||||

1905 | Rudski inversion method for reduction of masses above geoid | |||||

1905 | Wild theodolite with microscope for both verniers next to telescope | |||||

1905 | Bykow. Suggested level recording inst. using pendulum and rev. counter. | |||||

1905 | -54. Triangulation Cape to Cairo. ie 30th meridian | |||||

1906 | Photocomposing machine in lithography by Huebner | |||||

1906 | Helmert method to find earth axes from trig and gravity obs. | |||||

1907 | Stereoplotter by Thompson | |||||

1907 | Schweydar theory of coeff of rigidity of earth. | |||||

1907 | Wild.Coincidence setting of both verniers with microscope. | |||||

1908 | Stereo autograph by von Orel of Vienna. | |||||

1908 | Carl Zeiss Jena established geodetic instrument section | |||||

1908 | -11. Triangulation in Fiji by Lee, Rimmer, McCaw | |||||

1909 | Zeiss parallelogram by Bauersfeld | |||||

1909 | Prismastrolabium by vonClaude & Driencourt. | |||||

1909 | Pratt-Hayford isostatic system | |||||

1910 | Hayford investigated mean ellipsoid from gravity data | |||||

1910 | Zwicky tacheometer with two telescopes. | |||||

1910 | Photographic cross-sections of tunnel profiles in Austria | |||||

1910 | -13. Antarctic triangulation Ross Sea area by Debenham | |||||

1911 | Further 2736 absolute garvity stations. Helmert forula readjusted 1915 | |||||

1911 | Hammer method of adjusting trilateration. | |||||

1911 | Wilski double wire shaft plumbing. | |||||

1911 | Wild's Zeiss III precision level with parallel plate micrometer. | |||||

1912 | Bowie working on isostasy | |||||

1912 | Foundation of International Time Bureau in Paris. (BIH). | |||||

1912 | Kruger method to transform conformal coords to adjacent zones | |||||

1912 | -13. Wegener found large vertical refraction in Greenland | |||||

1912 | -17. Bowie gravity obs in USA, Canada, India and Europe. | |||||

1912 | -21. Second geodetic levelling of Great Britain | |||||

1913 | Tardivo at Int. Cong. described aerial photog. from aeroplanes for mapping. | |||||

1914 | Haussmann suggested a gyrotheodolite | |||||

1914 | -18. Karolus, Mittelstadt & Huttel determined speed of light on geodetic base near Leipzig. | |||||

1917 | Bowie published "Investigations of gravity and isostasy. | |||||

1919 | IUGG formed. Germany only joined in 1956 | |||||

1920 | Karolus constructed modern Kerr cell as used in geodimeter. | |||||

1921 | Astrolabe attachment for theodolite by Reeves. | |||||

1921 | Stein found evidence of Indus inch inGobi desert. | |||||

1921 | Wild founded own workshop in Heerbrugg | |||||

1922 | Anschutz constructed first gyrotheodolite. | |||||

1922 | Parana river crossing. Levels by simult. z.d. | |||||

1922 | -27. Athanassiadis (Gk) suggested to link Crete with N Africa by flare | |||||

triangulation with balloons | ||||||

1923 | Vening Meinesz working on isostasy | |||||

1923 | Plane parallel plate for Vaisala interference comparator. | |||||

1923 | Design of Wild T2 complete | |||||

1923 | Vening Meinesz gravity obs in submarine | |||||

1924 | Glass circles & optical micrometer designed by Wild, built by Zeiss. | |||||

1924 | Zeiss-Bosshardt double-image tacheometer. | |||||

1924 | Barometric lapse rate formula. | |||||

1924 | Acceptance of Hayford ellipsoid as Int. Ellipsoid of IUGG | |||||

1924 | Foundation of Baltic GeodeticCommission by Bonsdorff | |||||

1924 | -38. Heiskanen observed over 2000 gravity stations. | |||||

1924 | -38. Airy-Heiskanen isostatic system | |||||

1925 | Launch of Wild T3 | |||||

1925 | Defant- tidal theory | |||||

1926 | Research into vertical refraction by Geiger and Kukkamaki | |||||

1926 | Heiskanen ellipsoid | |||||

1926 | Astro levelling by Aguilar in Argentina. | |||||

1926 | CTS 1" theodolite | |||||

1927 | Sun compass by Bumstead for polar flights. | |||||

1927 | Coast to coast precise levelling in USA | |||||

1927 | Somigliani derived major axis of geoid from gravity measures alone | |||||

1927 | Differential analyser for use in digital computer By Bush, USA | |||||

1927 | Experiments with echosounders by Behm (G) | |||||

1928 | Triangulation of Alai-Pamir by Germans under Finsterwalder | |||||

1928 | IAG first published International Bibliography. | |||||

1928 | Static quartz gravimeter by Noergaard | |||||

1928 | Empirical gravity formula by Heiskanen | |||||

1929 | Deflection of dams by precise geodetic methods. Lang, Switzerland | |||||

1929 | Vening-Meinesz three pendulum gravimeter for use at sea | |||||

1930 | Somigliani and Cassini added theoretical term to to Heiskanen 1928 formula | |||||

1930 | Holweck-Lejay astatic pendulum | |||||

1930 | Lejay, S.J. director of Observatory Zi-Ka-Wei near Shanghai | |||||

1930 | Gravimeters specifically for oil exploration. Truman, USA | |||||

1930 | 45º prismatic astrolabe by Baker. | |||||

1930 | Pendulum astrolabe by Willis. | |||||

1930 | Error analysis by Ljutz. | |||||

1930 | Spring balance principle gravimeter | |||||

1930 | -31. Wegener Greenland crossing. Used trig. levelling. | |||||

1931 | Haalck gravimeter on barometric principle | |||||

1931 | Heiskanen tables of isostatic reductions | |||||

1931 | Hildebrand special optical plummet for shipbuilding. | |||||

1931 | Gas pressure gravimeter | |||||

1931 | -41. Vening-Meinesz modified Airy regional floating theory. | |||||

1931 | Heiskanen definition of spheroidal earth. See p 83 | |||||

and also equilibrium earth. | ||||||

1932 | Photo.registration of horz. circle reading on theodolites. Berroth | |||||

1932 | Bifilar gravimeter by Tomaschek | |||||

1933 | Berroth established procedures for flare triangulation | |||||

1934 | Triangulation of Nanga-Parbat | |||||

1934 | Hirvonen used Stokes formula to recompute geoid. | |||||

1934 | -35. Heye, Cooke absolute gravity in washington. | |||||

1935 | N African parallel arc Nemours - Carthago and W to Casablanca. | |||||

1935 | Echo sounder improved by Wood and others. | |||||

1935 | Germany instructed Surveyors to switch to centesimal circle graduations | |||||

1935 | Australian SArmy Svy Corp bought first metric tapes | |||||

1935 | -55. Secoind Geodetic levelling of Finland by Kukkamaki et al. | |||||

1936 | Int.Lat. Service moved to Naples from Kimura | |||||

1936 | Hilger Watts 1" microptic theodolite | |||||

1936 | Three way optical plumb by Zeiss | |||||

1936 | Norlund pioneered hydrostatic precise levelling | |||||

1936 | -38. J S Clark NPL absolute gravity | |||||

1938 | Charter for OS recommended metric grid. | |||||

1938 | Plane parallel plate for precise level by Wild(Zeiss). | |||||

1938 | Calibration od invar base wires by Vaisala interference comparator | |||||

1938 | Cowle, USA had idea of adjustment by electrical analogue | |||||

1939 | Graf, Berlin. static gravimeter | |||||

1939 | Test of Berroth flare triangulation inGermany | |||||

1939 | Automatic level compensator by Meissner | |||||

1941 | Hinterkeuser error theory of flare triangulation | |||||

1941 | Gulf underwater gravimeter | |||||

1942 | Roelofs solar prism | |||||

1942 | Krasovsky ellipsoid | |||||

1943 | ICAN Standard Atmosphere for barometric levelling. | |||||

1944 | HARVARD MARK 1 by Aiken. Electronic computer with punch tape. | |||||

1944 | Underwater photogrammetry began in USA | |||||

1945 | Multiplex radar controlled air photography. | |||||

1945 | ENIAC by Mauchly et al. USA. | |||||

1945 | Norlund levelled 21 km across Baltic Sea using lead pipe. | |||||

1945 | Split of Carl Zeiss Jena to give Carl-Zeiss Obserkochen & VEB Carl Zeiss | |||||

1945 | -46. Flare triangulation by British, US and Norway | |||||

1946 | -51. Rice and van Steenwijk studies on deflection of plumbline | |||||

Absolute gravity work by Bullard, Ivanov, Browne, Morelli, Jeffreys, Woollard | ||||||

1946 | Russian tri-axial ellipsoid. See p 84 | |||||

1946 | Dutch discovered radio astro with ex-war radar. | |||||

1946 | Vaisala stellar triangulation | |||||

1947 | Speert, USGS adjustment by electrical analogue. | |||||

1947 | Electric eye for telescopes by Gigas | |||||

1947 | -48. Fully automatic elevation recorders | |||||

1947 | -48. Global triangulation initiated by Finns. Hirvonen in Brazil and | |||||

Kukkamaki in W Africa | ||||||

1948 | Mears, Whitford USA telescope for occultation obs. | |||||

1948 | Jungwirth modified submarine gyro compass to fit theodolite | |||||

1948 | Invention of transistor by Bell Laboratories USA | |||||

1949 | -65. Level testers of high precision. See p 85 | |||||

1950 | Reflecting telescope by Kern for 1st order triangulation | |||||

1950 | Gyroscopes in aerial cameras. (Italy) | |||||

1950 | Gyroscopes in theodolites by Fennel. | |||||

1950 | Moves by Hotine, Marussi, Levallois, Dufour to replace geoid by quasi geoid | |||||

Molodensky and Hirvonen defined by space coords instead of siurface coords. | ||||||

1950 | Hough & Whitten adjusted SW European & N African trig. blocks | |||||

1950 | Van Heel,Moonen & Richardus used interference patterns in alignment svy. | |||||

1950 | Honkasalo inver-mercury thermometer for baselines | |||||

1951 | Automatic level Ni2 by Zeiss Oberkochen | |||||

1951 | Fourth connection UK - France by triangulation. | |||||

1951 | -59. Third geodetic levelling of Great britain | |||||

1952 | Askania Askania micro-barometer for diff. of height. | |||||

1952 | Random disturbances of earth rotation. Brouwer, USA. | |||||

1953 | VEB Carl Zeiss 1" theodolite 010 | |||||

1953 | Wankie and Sabi bases (S Rhod) by Bradford. Invar resistance thermometer. | |||||

1954 | Ellenberger reported on elasticity of earth. | |||||

1954 | Invention of geodimeter ?? | |||||

1955 | Diff. between dynamic and orthometric hts discussed in Rome | |||||

1956 | Advent of satellites | |||||

1956 | Irene Fisher geoid chart of USA | |||||

1956 | Hough ellipsoid of Western hemisphere | |||||

1956 | Obs of satellites by interferometer, Doppler effect and radar. | |||||

1957 | Sea surface gravimeter by Graf. | |||||

1957 | Fisher- Chovitz figure of earth. See p 88 | |||||

1957 | Jerie analogue computer | |||||

1957 | -58. International Geophysical Year | |||||

1958 | Baker-Nunn camera for satellite obs. | |||||

1958 | Several independent adjustments of 68 European level loops. See pp 88,89 | |||||

1958 | Tellurometer traverses replace triangulation in Australia | |||||

1959 | Development of super wide angle camera by Wild | |||||

1959 | First spatial photograph of moon by Lunik III | |||||

1959 | Prismastrolabium by Danjou. | |||||

1960 | Fennel, Kassel gyrotheodolite with suspended gyroscope. | |||||

1960 | Int. agreement of metre as 1 650 763.73 wavelengths krypton 86 in vacuo | |||||

1960 | Yard - metre relation as 0.9144 m | |||||

1960 | De Graaff Hunter theory on shape of earth suirface | |||||

1960 | Harrison USA gravity measurement in aeroplane | |||||

1960 | Astro-geodetic World Datum for geoid. | |||||

Also agreement on standards of length. See p 89 | ||||||

1960 | Mobile cameras for satellite geodesy | |||||

1961 | Irene Fischer comprehensive study of shape of geoid. | |||||

1961 | Cooperation between NASA and USCGS in geodetic satellite programme | |||||

1963 | Fifth connection England - France by triangulation & trilateration | |||||

1963 | Hydrostatic levelling using frozen lake Ijsselmeer | |||||

1964 | Automatic level Zeiss Ni4 by Drodofsky. Spirit bubble as pendulum | |||||

1965 | Light weight gyrotheodolites by Wild, MOM etc | |||||

1966 | VEB Carl Zeiss astro-geodetic theo 0.2" | |||||

1967 | Daylight signalling lamp with quartziodine globes. Australia | |||||

1967 | Geodolite by Spectra Physics, USA | |||||