Showing 10 items matching "telescope mirror"
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Federation University Historical CollectionScientific Instrument, Telescope Mirror, 1929
... Telescope Mirror......telescope mirror...Stored between a pair of 5cm thick 16 x 20 pieces of polystyrene slab, hollowed to accomodate mirror. Telescope Mirror Scientific Instrument ...Probably made and used by Dick Richards, who lectured in Physics at the Ballarat School of Mines, and later became the principal. Earlier Dick Richards had been a member of Shackleton's Antarctic Exploration Expedition. A 15cm diameter glass disc, 2.3 cm thick. ONe side is ground concave to 7'=5" (s s7 cm) radius. Rough-hewn circumference. Stored between a pair of 5cm thick 16 x 20 pieces of polystyrene slab, hollowed to accomodate mirror.scientific instruments, mirror, telescope mirror, dick richards, r.w. richards -
Federation University Historical CollectionInstrument - Object, Telescope
... Black telescope with 9 inch mirror and large counterweight. ...The telescope was reconditioned by former staff member Graeme Hood. telescope observatory On the back of the mirror are the following words "G M Riley Sunshine 1922" Black telescope with 9 inch mirror and large counterweight. ...This telescope was used at the Ballarat School of Mines, and used to be located on the roof of the Ballarat Technical Art School (Gribble Building) at the Ballarat School of Mines. The telescope was reconditioned by former staff member Graeme Hood. Black telescope with 9 inch mirror and large counterweight. On the back of the mirror are the following words "G M Riley Sunshine 1922"telescope, observatory -
Federation University Historical CollectionEquipment - Equipment - Scientific, Heliostat
... mirror, which turns so as to keep reflecting sunlight toward a predetermined target, compensating for the sun's apparent motions in the sky. Nowadays, most heliostats are used for daylighting or for the production of concentrated solar power, usually to generate electricity. They are also sometimes used in solar cooking. A few are used experimentally to reflect motionless beams of sunlight into solar telescopes...mirror, which turns so as to keep reflecting sunlight toward a predetermined target, compensating for the sun's apparent motions in the sky. Nowadays, most heliostats are used for daylighting or for the production of concentrated solar power, usually to generate electricity. They are also sometimes used in solar cooking. A few are used experimentally to reflect motionless beams of sunlight into solar telescopes ...A heliostat (from helios, the Greek word for sun, and stat, as in stationary) is a device that includes a mirror, usually a plane mirror, which turns so as to keep reflecting sunlight toward a predetermined target, compensating for the sun's apparent motions in the sky. Nowadays, most heliostats are used for daylighting or for the production of concentrated solar power, usually to generate electricity. They are also sometimes used in solar cooking. A few are used experimentally to reflect motionless beams of sunlight into solar telescopes. Before the availability of lasers and other electric lights, heliostats were widely used to produce intense, stationary beams of light for scientific and other purposes.Black metal and brass object with scale measure (0 - 90 and glass circle on top that can be raised and lowered. Three legs with brass feet.Markings on scale measure. heliostat, metal, brass, mirror, guage -
Frankston RSL Sub BranchMemorabilia - Level, Abney
... telescope. An Abney level and clinometer, is an instrument used in surveying which consists of a fixed sighting tube, a movable spirit level that is connected to a pointing arm, and a protractor scale. An internal mirror ...Square gunsight telescope.An Abney level and clinometer, is an instrument used in surveying which consists of a fixed sighting tube, a movable spirit level that is connected to a pointing arm, and a protractor scale. An internal mirror allows the user to see the bubble in the level while sighting a distant target. It can be used as a hand-held instrument or mounted on a Jacob's staff for more precise measurement, and it is small enough to carry in a coat pocket -
Flagstaff Hill Maritime Museum and VillageInstrument - Optical, Telescope, 1869
... Then in 1668, Newton produces the first successful reflecting telescope using a two-inch diameter concave spherical mirror. This opened the door to magnifying objects millions of times far beyond what could ever be obtained with a lens. ...Then in 1668, Newton produces the first successful reflecting telescope using a two-inch diameter concave spherical mirror. This opened the door to magnifying objects millions of times far beyond what could ever be obtained with a lens. ...The discovery of the first telescope in 1608 can be attributed to Hans Lippershey of the Netherlands when he discovers that holding two lenses up some distance apart bring objects closer. He applies for a patent on his invention and this becomes the first documented creation of a telescope. Then in 1668, Newton produces the first successful reflecting telescope using a two-inch diameter concave spherical mirror. This opened the door to magnifying objects millions of times far beyond what could ever be obtained with a lens. It wasn’t until 1729 that Chester Moor Hall develops an achromatic lens (two pieces of glass with different indices of light refraction combined produce a lens that can focus colours to almost an exact point resulting in much sharper images but still with some distortion around the edges of the image. Then in 1729 Scottish instrument maker James Short invents the first parabolic and elliptic, distortion-less mirror ideal for reflecting telescopes. We now come to John Dollond who improves upon the achromatic objective lens by placing a concave flint glass lens between two convex crown glass lenses. This had the effect of improving the image considerably. Makers Information: John Dollond (1707-1761) London England he was a maker of optical and astronomical instruments who developed an achromatic (non-colour distorting) refracting telescope and practical heliometer. A telescope that used a divided lens to measure the Sun’s diameter and the angles between celestial bodies. The son of a Huguenot refugees Dollond learned the family trade of silk weaving. He became proficient in optics and astronomy and in 1752 his eldest son, Peter joined his father in an optical business, in 1753 he introduced the heliometer. In the same year, he also took out a patent on his new lenses. He was elected a fellow of the Royal Society in May 1761 but died suddenly in November and his share in the patent passed to his son Peter. In subsequent squabbles between Peter and the many London opticians who challenged his patent, Peter’s consistent position was that, whatever precedents there may have been to his achromatic lenses, his father had independently reached his practical technique on the basis of his theoretical command of Newtonian optics. As a result of maintaining his fathers patent, Dollond s became the leading manufacturer of optical instruments. For a time in the eighteenth and nineteenth century the word 'Dollond' was almost a generic term for telescope rather like 'Hoover; is to vacuum cleaner. Genuine Dollond telescopes were considered to be amongst the best. Peter Dollond (1731-1820) was the business brain behind the company which he founded in Vine Street, Spitalfields in 1750 and in 1752 moved the business to the Strand London. The Dollonds seem to have made both types of telescopes (reflecting and refracting), possessing the technology to produce significant numbers of lenses free of chromatic aberration for refracting telescopes. A Dollond telescope sailed with Captain Cook in 1769 on his voyage to observe the Transit of Venus. Thomas Jefferson and Admiral Lord Nelson were also customers of the Dollonds. Dollond & Co merged with Aitchison & Co in 1927 to form Dollond & Aitchison, the well-known high street chain of opticians, now fully part of Boots Opticians. They no longer manufacture but are exclusively a retail operation. John Dollond's experiments in optics and how different combinations of lenses refract light and colour gave a better understanding of the divergent properties of lenses. That went on to inform and pave the way for the improvement of our understanding of optics that are represented today. Dollond was referred to in his time as the "Father of practical optics" as a leader in his field he received many prestigious awards. The telescope in the collection is a good example of one of Dollonds early library telescopes and its connection with one of England's 18th-century pioneers in optical development is in itself a significant and an important item to have within the collection. Telescope: one tube ships Day and Night telescope, with a brass inner tube and a timber main tube covered in leather. Made in 1869 by Dolland, London."Dolland London" "Day or Night" "Royal National Life Boat Institution" "1869"flagstaff hill, shipwreck coast, warrnambool, maritime museum, maritime village, telescope, dolland, night and day, royal national life boat instution -
Federation University Historical CollectionLetter - Correspondence, E.J. Barker, Letter relating the the Ballarat Observatory, 1966, 1966
... The telescopes in question were three Newtonian reflectors, one Cassegrainian focus reflector and one "Calver" telescope on altazimuth mounting. .4) Former Ballarat School of Mines Principal, Dick Richards, writes to Jack Barker regarding the telescopes. Mention is made of John Brittain's ten inch mirror on a metal tube, stored on the penthouse on the roof of the Art School. .5) Ballarat School of Mines librarian, Heather Durant, writes to Jack Barker . .6) Simple timeline relating to the Ballarat School of Mines .7) Extracts for the Ballarat School of Mines Annual Reports relating to the Ballarat Observatory, the James Oddie donation, and the transfer of the Observatory to the Ballarat East Town Council. 8)Two quarto typed pages from Jack Barker to Bert Strange outlining the research undertaken to report that the telescopes were not in the possession of the Ballarat School of Mines. ...The telescopes in question were three Newtonian reflectors, one Cassegrainian focus reflector and one "Calver" telescope on altazimuth mounting. .4) Former Ballarat School of Mines Principal, Dick Richards, writes to Jack Barker regarding the telescopes. Mention is made of John Brittain's ten inch mirror on a metal tube, stored on the penthouse on the roof of the Art School. .5) Ballarat School of Mines librarian, Heather Durant, writes to Jack Barker . .6) Simple timeline relating to the Ballarat School of Mines .7) Extracts for the Ballarat School of Mines Annual Reports relating to the Ballarat Observatory, the James Oddie donation, and the transfer of the Observatory to the Ballarat East Town Council. 8)Two quarto typed pages from Jack Barker to Bert Strange outlining the research undertaken to report that the telescopes were not in the possession of the Ballarat School of Mines. ...The Ballarat Observatory is situated at Mount Pleasant.Correspondence relating the the Ballarat Observatory. .1) Robert J. Strange, Secretary of the Ballaarat Astronomical Society, writes to E.J. Barker (Principal, Ballarat School of Mines) regarding ownership of telescopes. .2) E.J. Barker (Principal, Ballarat School of Mines) writes to Bert Strange concerning ownership of telescopes .3) Bert Strange writes to Jack Barker with details of the telescopes, including references to James Oddie. The telescopes in question were three Newtonian reflectors, one Cassegrainian focus reflector and one "Calver" telescope on altazimuth mounting. .4) Former Ballarat School of Mines Principal, Dick Richards, writes to Jack Barker regarding the telescopes. Mention is made of John Brittain's ten inch mirror on a metal tube, stored on the penthouse on the roof of the Art School. .5) Ballarat School of Mines librarian, Heather Durant, writes to Jack Barker . .6) Simple timeline relating to the Ballarat School of Mines .7) Extracts for the Ballarat School of Mines Annual Reports relating to the Ballarat Observatory, the James Oddie donation, and the transfer of the Observatory to the Ballarat East Town Council. 8)Two quarto typed pages from Jack Barker to Bert Strange outlining the research undertaken to report that the telescopes were not in the possession of the Ballarat School of Mines. ballarat school of mines, jack barker, e.j. barker, ballarat observatory, bert strange, robert f. strange, telescopes, dick richards, r.w. richards, heather durant, mount pleasant, mt pleasant -
Federation University Historical CollectionScientific Instrument, Theodolite: Serial No. 52608, c1940s
... Aladide levelling bubble with top mirror. Fully rotatable telescope with gunsight. Fits tripod Catalogue Number 4107....Aladide levelling bubble with top mirror. Fully rotatable telescope with gunsight. Fits tripod Catalogue Number 4107. ...Theodolite with internal focussing. One plate bubble level. Three levelling screws. Engraved. "Crosshair" and stodia lines. Aladide levelling bubble with top mirror. Fully rotatable telescope with gunsight. Fits tripod Catalogue Number 4107.scientific instruments, theodolite, e.r. watts & son ltd -
Federation University Historical CollectionInstrument - Scientific Instrument, Dumpy Level, 05/1950
... Telescope with cross hairs and stoidia wites. Internal focussing. Vertical tilt adjusted with vernier mocrometer screw mirror lid longitudinal bubble level. ...Inside box lid - Manufacturers label; grades table label, calibration label reading "instrument No 67 543, date 13.5.50" (ink faded) constant: +0.19 ft" Telescope with cross hairs and stoidia wites. Internal focussing. Vertical tilt adjusted with vernier mocrometer screw mirror lid longitudinal bubble level. ...Used for surveying classes at the Ballarat School of Mines.Telescope with cross hairs and stoidia wites. Internal focussing. Vertical tilt adjusted with vernier mocrometer screw mirror lid longitudinal bubble level. Pea bubble level on plate. Housed in wooden storage carry box. Fits tripod cat. no. 4118Serial number 67543 On box lid in white paing "L 6". In yellow paing "59". Inside box lid - Manufacturers label; grades table label, calibration label reading "instrument No 67 543, date 13.5.50" (ink faded) constant: +0.19 ft"dumpy, level, surveying, scientific instrument, e.r. watts & son ltd, ballarat school of mines -
Parks Victoria - Wilsons Promontory LightstationTelescope
... The telescope is original to the Wilsons Promontory Lightstation and was provided by the Department of Shipping and Transport in about 1900. The device magnifies images of distant objects through its curved interior mirrors, and lightkeepers used this telescope to monitor and record the names of ships, the time they passed, and their direction, as well as read meanings of flags and other visual signals communicated by vessels. ...Parks Victoria - Wilsons Promontory Lightstation Lighthouse track Wilsons Promontory National Park 3960 gippsland The telescope is original to the Wilsons Promontory Lightstation and was provided by the Department of Shipping and Transport in about 1900. The device magnifies images of distant objects through its curved interior mirrors, and lightkeepers used this telescope to monitor and record the names of ships, the time they passed, and their direction, as well as read meanings of flags and other visual signals communicated by vessels. ...The telescope is original to the Wilsons Promontory Lightstation and was provided by the Department of Shipping and Transport in about 1900. The device magnifies images of distant objects through its curved interior mirrors, and lightkeepers used this telescope to monitor and record the names of ships, the time they passed, and their direction, as well as read meanings of flags and other visual signals communicated by vessels. The telescope is similar to Cape Nelson’s two metre long telescope, which is included in the VHR registration for the Cape Nelson Lightstation. It is particularly important for its good condition, completeness and confirmed provenance and has first level contributory significance to the cultural heritage values of the lightstation..1 Brass telescope, cylindrical tube shape with mobile interfolding sections. Middle section of tube has been covered with textile or leather and painted black. Narrow plaited rope fixed as a border to this section is also painted black. .2. The telescope is attached by a brass fitting to a wooden tripod on a three legged triangular ply wood base with three castors. -
Flagstaff Hill Maritime Museum and VillageInstrument - Telescope, Mid-18th Century
... That same year, the Scottish instrument maker James Short developed parabolic and elliptical mirrors that were better suited to reflecting telescopes because they reduced optical distortion. ...That same year, the Scottish instrument maker James Short developed parabolic and elliptical mirrors that were better suited to reflecting telescopes because they reduced optical distortion. ...This Day or Night telescope, made by John Dollond, was designed for use in a range of lighting conditions, as its name suggests. Telescopes are optical instruments that make distant objects appear larger and closer, thereby extending the range of what the human eye can observe. The development of the telescope was gradual, shaped by a series of important advances in optical science. In 1608, the Dutch spectacle-maker Hans Lippershey discovered that when two lenses were held apart in a particular way, distant objects appeared closer. He applied for a patent for this invention, creating the first documented telescope. In 1668, Isaac Newton produced the first successful reflecting telescope, using a two-inch concave spherical mirror. This marked a major step forward, demonstrating that mirrors could overcome some of the limitations of lenses and greatly improve magnification. Further progress followed in the eighteenth century. In 1729, Chester Moor Hall developed the achromatic lens by combining two types of glass with different refractive properties. This reduced colour distortion and produced a sharper image, although some edge distortion remained. That same year, the Scottish instrument maker James Short developed parabolic and elliptical mirrors that were better suited to reflecting telescopes because they reduced optical distortion. Building on these advances, John Dollond improved the achromatic objective lens by placing a concave flint-glass lens between two convex crown-glass lenses, considerably enhancing image quality. Maker’s information. John Dollond (1707–1761), of London, was a maker of optical, scientific and astronomical instruments best known for developing the achromatic refracting telescope. He also introduced a practical heliometer, a telescope fitted with a divided lens that could be used to measure the Sun’s diameter and the angular distance between celestial bodies. The son of Huguenot refugees, Dollond first learned the family trade of silk weaving before turning his attention to optics and astronomy, in which he became highly skilled. In 1753, Dollond patented his improved lenses, the same year he had introduced the heliometer. In 1761, John Dollond was appointed as optician to George III and the Duke of York. He was also elected a Fellow of the Royal Society in May 1761, but died suddenly later that year in November. His share of the patent then passed to his eldest son, Peter. In later disputes between Peter Dollond and rival London opticians who challenged the patent, Peter consistently argued that, whatever earlier precedents may have existed, his father had independently developed a practical method for producing achromatic lenses through his command of Newtonian optics. By successfully defending the patent, the Dollond firm became one of the leading manufacturers of optical instruments. During the eighteenth and nineteenth centuries, the name ‘Dollond’ was at times used almost generically to mean ‘telescope,’ reflecting the firm’s reputation. Genuine Dollond telescopes were regarded as among the finest available. Peter Dollond (1731–1820) was the driving force behind the family business. He had founded a small optical business in 1750 on Vine Street, Halton Garden, with his father's guidance. The success of the business led to his father joining him in partnership in 1752. In 1959, J Dollond and Son opened a shop on The Strand, London. Dollonds appear to have produced both reflecting and refracting telescopes, and they possessed the technical skill to manufacture significant numbers of lenses largely free from chromatic aberration. In 1766, Peter went into partnership with his younger brother, John, and they traded under the name P and J Dollond. They supplied optical instruments for Captain Cook and George Hadley, an English lawyer and Meteorologist. In 1769, Captain Cook travelled with a Dollond telescope on the voyage to observe the Transit of Venus. Other notable customers included Thomas Jefferson and Admiral Lord Nelson. In 1781, Peter Dollond made bifocal spectacles. In 1804, young John Dollond passed away. The following year, Peter Dollond went into partnership with his nephew, George Huggins, and Huggins legally changed his surname to Dollond, and the firm remained P and J Dollond. In the early 20th century, the company sold film cameras. The firm remained in the hands of Dollond family members until 1927, when Dollond & Co. merged with James Aitchison & Co. to form Dollond & Aitchison, the well-known high street chain of opticians, which continued making and selling prescription spectacles. Now fully part of Boots Opticians, the company no longer manufactures instruments and operates exclusively as a retail business. The telescope in the collection is an excellent example of one of Dollond’s early library telescopes. Its association with one of eighteenth-century England’s leading innovators in optical development gives it considerable historical significance and makes it an important object within the collection. John Dollond’s experiments in optics advanced the understanding of the divergent properties of lenses and made a lasting contribution to the development of practical optical science. His work helped lay the foundation for major improvements in the design and performance of optical instruments. In his own time, Dollond was celebrated as the “Father of practical optics” and received widespread recognition for his achievements in the field. Dollond telescopes were associated with the renowned mariners, Captain James Cook and Admiral Lord Nelson Telescope: Dollond's Telescope, Day or Night model navigational instrument. Telescope is mounted on wooden tripod stand that has folding legs. Brass telescope with leather sheath over barrel, adjustable angle fitting with brass wing nuts that join the legs to the top frame, which is then joined to the telescope pole by an adjustable screw fitting. Manufactured by Dollond, London. Inscription reads "Dollond London, Day or Night" and "DOLLOND LONDON"flagstaff hill maritime museum and village, maritime museum, maritime village, great ocean road, warrnambool, optical instrument, achromatic telescope, heliometer, light refraction, instrument maker, lens, transit of venus, astronomical telescope, concave lens, scientific instrument, navigation, navigational instrument, astronomy, dollond, dollond london, john dollond, peter dollond, dollond telescope, day or night telescope, floor-standing telescope, library telescope, hans lippershey, isaac newton, chester moor hall, james short, captain cook, thomas jefferson, admiral lord nelson, dollond & co, aitchison & co, dollond & aitchison, boots opticians, george iii, duke of york, george huggins, george dollond, p and j dollond, j dollond and son, spectacles, cameras
