1.
Limestone
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Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate, about 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, most cave systems are through limestone bedrock. The first geologist to distinguish limestone from dolomite was Belsazar Hacquet in 1778, like most other sedimentary rocks, most limestone is composed of grains. Most grains in limestone are skeletal fragments of organisms such as coral or foraminifera. Other carbonate grains comprising limestones are ooids, peloids, intraclasts and these organisms secrete shells made of aragonite or calcite, and leave these shells behind when they die. Limestone often contains variable amounts of silica in the form of chert or siliceous skeletal fragment, some limestones do not consist of grains at all, and are formed completely by the chemical precipitation of calcite or aragonite, i. e. travertine. Secondary calcite may be deposited by supersaturated meteoric waters and this produces speleothems, such as stalagmites and stalactites. Another form taken by calcite is oolitic limestone, which can be recognized by its granular appearance, the primary source of the calcite in limestone is most commonly marine organisms. Some of these organisms can construct mounds of rock known as reefs, below about 3,000 meters, water pressure and temperature conditions cause the dissolution of calcite to increase nonlinearly, so limestone typically does not form in deeper waters. Limestones may also form in lacustrine and evaporite depositional environments, calcite can be dissolved or precipitated by groundwater, depending on several factors, including the water temperature, pH, and dissolved ion concentrations. Calcite exhibits a characteristic called retrograde solubility, in which it becomes less soluble in water as the temperature increases. Impurities will cause limestones to exhibit different colors, especially with weathered surfaces, Limestone may be crystalline, clastic, granular, or massive, depending on the method of formation. Crystals of calcite, quartz, dolomite or barite may line small cavities in the rock, when conditions are right for precipitation, calcite forms mineral coatings that cement the existing rock grains together, or it can fill fractures. Travertine is a banded, compact variety of limestone formed along streams, particularly there are waterfalls. Calcium carbonate is deposited where evaporation of the leaves a solution supersaturated with the chemical constituents of calcite. Tufa, a porous or cellular variety of travertine, is found near waterfalls, coquina is a poorly consolidated limestone composed of pieces of coral or shells. During regional metamorphism that occurs during the building process, limestone recrystallizes into marble
2.
Photograph
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A photograph or photo is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic medium such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scenes visible wavelengths of light into a reproduction of what the eye would see. The process and practice of creating photographs is called photography, the word photograph was coined in 1839 by Sir John Herschel and is based on the Greek φῶς, meaning light, and γραφή, meaning drawing, writing, together meaning drawing with light. The first permanent photograph, a copy of an engraving, was made in 1822 using the bitumen-based heliography process developed by Nicéphore Niépce. In 1829 Niépce entered into a partnership with Louis Daguerre and the two collaborated to work out a similar but more sensitive and otherwise improved process, after Niépces death in 1833, Daguerre concentrated on silver halide-based alternatives. He named this first practical process for making photographs with a camera the daguerreotype and its existence was announced to the world on 7 January 1839 but working details were not made public until 19 August. Other inventors soon made improvements which reduced the exposure time from a few minutes to a few seconds, making portrait photography truly practical. The daguerreotype had shortcomings, notably the fragility of the image surface. Each was a unique opaque positive that could only be duplicated by copying it with a camera, inventors set about working out improved processes that would be more practical. By the end of the 1850s the daguerreotype had been replaced by the expensive and more easily viewed ambrotype and tintype. The mid-1930s saw the introduction of Kodachrome and Agfacolor Neu, the first easy-to-use color films of the modern multi-layer chromogenic type, the needs of the motion picture industry generated a number of special processes and systems, perhaps the best-known being the now-obsolete three-strip Technicolor process. Non-digital photographs are produced with a chemical process. In the two-step process the film captures a negative image. To produce an image, the negative is most commonly transferred onto photographic paper. Printing the negative onto transparent film stock is used to motion picture films. Alternatively, the film is processed to invert the negative image, such positive images are usually mounted in frames, called slides. Before recent advances in photography, transparencies were widely used by professionals because of their sharpness. Most photographs published in magazines were taken on color transparency film, originally, all photographs were monochromatic or hand-painted in color
3.
Microscope
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A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy, microscopic means invisible to the eye unless aided by a microscope. There are many types of microscopes, the most common is the optical microscope, which uses light to image the sample. Other major types of microscopes are the microscope, the ultramicroscope. The earliest microscopes were single lens magnifying glasses with limited magnification which date at least as far back as the wide use of lenses in eyeglasses in the 13th century. Compound microscopes, which combine an objective lens with an eyepiece to view a real image, the actual inventor of the compound microscope is unknown although many claims have been made over the years. These include what may be a claim by the son of Zacharias Janssen that his father invented the microscope and telescope as early as 1590. Historians note the compound microscope did not appear in the Netherlands until the 1620s, giovanni Faber coined the name microscope for the compound microscope Galileo submitted to the Accademia dei Lincei in 1625. The first detailed account of the construction of living tissue based on the use of a microscope did not appear until 1644, in Giambattista Odiernas Locchio della mosca. It was not until the 1660s and 1670s that the microscope was used extensively for research in Italy, marcello Malpighi in Italy began the analysis of biological structures, beginning with the lungs. Robert Hookes Micrographia had an impact, largely because of its impressive illustrations. A significant contribution came from Antonie van Leeuwenhoek who achieved up to 300 times magnification using a single lens microscope. He sandwiched a very small glass ball lens between the holes in two metal plates riveted together, and with a needle attached to mount the specimen. Then, Van Leeuwenhoek re-discovered red blood cells and spermatozoa, on 9 October 1676, he reported the discovery of micro-organisms. The performance of light microscopy depends as much on how the sample is illuminated as on how it is observed, early instruments were limited until this principle was fully appreciated and developed, and until electric lamps were available as light sources. In 1893 August Köhler developed a key principle of sample illumination, Köhler illumination and this method of sample illumination produces even lighting and overcomes the limited contrast and resolution imposed by early techniques of sample illumination. In the early 20th century a significant alternative to light microscopy was developed, ernst Ruska started development of the first electron microscope in 1931 which was the transmission electron microscope. The transmission electron microscope works on the principle as an optical microscope but uses electrons in the place of light
4.
Optical microscope
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The optical microscope, often referred to as light microscope, is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were invented in their present compound form in the 17th century. Basic optical microscopes can be simple, although there are many complex designs which aim to improve resolution. The image from a microscope can be captured by normal light-sensitive cameras to generate a micrograph. Originally images were captured by photographic film but modern developments in CMOS, purely digital microscopes are now available which use a CCD camera to examine a sample, showing the resulting image directly on a computer screen without the need for eyepieces. Alternatives to optical microscopy which do not use visible light include scanning electron microscopy, there are two basic types of optical microscopes, simple microscopes and compound microscopes. A simple microscope is one which uses a lens for magnification. A compound microscope uses several lenses to enhance the magnification of an object, the vast majority of modern research microscopes are compound microscopes while some cheaper commercial digital microscopes are simple single lens microscopes. Compound microscopes can be divided into a variety of other types of microscopes which differ in their optical configurations, cost. A simple microscope uses a lens or set of lenses to enlarge an object through angular magnification alone, the use of a single convex lens or groups of lenses are still found in simple magnification devices such as the magnifying glass, loupes, and eyepieces for telescopes and microscopes. A compound microscope uses a close to the object being viewed to collect light which focuses a real image of the object inside the microscope. That image is magnified by a second lens or group of lenses that gives the viewer an enlarged inverted virtual image of the object. The use of a compound objective/eyepiece combination allows for higher magnification. Common compound microscopes often feature exchangeable objective lenses, allowing the user to quickly adjust the magnification, a compound microscope also enables more advanced illumination setups, such as phase contrast. There are many variants of the optical microscope design for specialized purposes. Comparison microscope, which has two light paths allowing direct comparison of two samples via one image in each eye. Inverted microscope, for studying samples from below, useful for cell cultures in liquid, student microscope, designed for low cost, durability, and ease of use. Polarizing microscope, similar to the petrographic microscope, phase contrast microscope, which applies the phase contrast illumination method
5.
Roman Vishniac
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Roman Vishniac was a Russian-American photographer, best known for capturing on film the culture of Jews in Central and Eastern Europe before the Holocaust. A major archive of his work now rests at the International Center of Photography, Vishniac was a versatile photographer, an accomplished biologist, an art collector and teacher of art history. He also made significant scientific contributions to photomicroscopy and time-lapse photography, Vishniac was very interested in history, especially that of his ancestors, and strongly attached to his Jewish roots, he was a Zionist later in life. Roman Vishniac won international acclaim for his photos of shtetlach and Jewish ghettos, celebrity portraits and his book A Vanished World, published in 1983, made him famous and is one of the most detailed pictorial documentations of Jewish culture in Eastern Europe in the 1930s. Vishniac was also remembered for his humanism and respect for life, in August 2014, the International Center for Photography in New York City announced that 9,000 of Vishniacs photos, many never printed or published before, would be posted in an online database. Vishniac was born in his grandparents dacha outside Saint Petersburg, in the town of Pavlovsk, Vishniac also had a sister, Katja. During the summer months, the Vishniac family left Moscow, as it became uncomfortably hot, as a child, Vishniac was fascinated by biology and photography, and his room was filled with plants, insects, fish and small animals. On his seventh birthday, he got a microscope from his grandmother, to which he hooked up a camera. Young Vishniac used this extensively, viewing and photographing everything he could find, from dead insects to animal scales, to pollen. Until the age of ten, Vishniac was homeschooled, from ten to seventeen, beginning in 1914, he spent six years at Shanyavsky Institute in Moscow. At the Institute he studied zoology, as a graduate student, he worked with prestigious biologist Nikolai Koltzoff, experimenting with inducing metamorphosis in axolotl, a species of aquatic salamander. While his experiments were a success, Vishniac was not able to publish a paper detailing his findings due to the chaos in Russia, in spite of this, he went on to take a three-year course in medicine. In 1918, Vishniacs immediate family moved to Berlin because of anti-Semitism spurred by uprisings against the Bolsheviks, Roman followed them and, shortly after arriving, married Luta Bagg, who gave birth to two children, Mara and Wolf. In his free time, he studied Far Eastern Art at the University of Berlin, Vishniac researched endocrinology and optics, and did some photography. In Berlin, he initiated his public speaking career by joining the Salamander Club. Vishniac developed and printed these pictures in his room in his Berlin apartment. Further trips to Eastern Europe were undertaken between 1935 and 1938, again at the behest of the JDC, Vishniac used both a Leica and a Rolleiflex camera in his photography. In 1939, his wife and children moved to Sweden to stay with Lutas parents and he met his parents in Nice that summer
6.
Robert Hooke
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Robert Hooke FRS was an English natural philosopher, architect and polymath. Allan Chapman has characterised him as Englands Leonardo, Robert Gunthers Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke. Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle and he built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. Much of Hookes scientific work was conducted in his capacity as curator of experiments of the Royal Society, much of what is known of Hookes early life comes from an autobiography that he commenced in 1696 but never completed. Richard Waller mentions it in his introduction to The Posthumous Works of Robert Hooke, the work of Waller, along with John Wards Lives of the Gresham Professors and John Aubreys Brief Lives, form the major near-contemporaneous biographical accounts of Hooke. Robert Hooke was born in 1635 in Freshwater on the Isle of Wight to John Hooke, Robert was the last of four children, two boys and two girls, and there was an age difference of seven years between him and the next youngest. Their father John was a Church of England priest, the curate of Freshwaters Church of All Saints, Robert Hooke was expected to succeed in his education and join the Church. John Hooke also was in charge of a school, and so was able to teach Robert. He was a Royalist and almost certainly a member of a group who went to pay their respects to Charles I when he escaped to the Isle of Wight, Robert, too, grew up to be a staunch monarchist. As a youth, Robert Hooke was fascinated by observation, mechanical works and he dismantled a brass clock and built a wooden replica that, by all accounts, worked well enough, and he learned to draw, making his own materials from coal, chalk and ruddle. Hooke quickly mastered Latin and Greek, made study of Hebrew. Here, too, he embarked on his study of mechanics. It appears that Hooke was one of a group of students whom Busby educated in parallel to the work of the school. Contemporary accounts say he was not much seen in the school, in 1653, Hooke secured a choristers place at Christ Church, Oxford. He was employed as an assistant to Dr Thomas Willis. There he met the natural philosopher Robert Boyle, and gained employment as his assistant from about 1655 to 1662, constructing, operating and he did not take his Master of Arts until 1662 or 1663
7.
Antonie van Leeuwenhoek
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Antonie Philips van Leeuwenhoek was a Dutch businessman, scientist, and one of the notable representatives in the golden age of Dutch science and technology. A largely self-taught man in science, he is known as the Father of Microbiology. Van Leeuwenhoek is best known for his work in the field of microscopy. Raised in Delft, in the Dutch Republic, Van Leeuwenhoek worked as a draper in his youth and he made a name for himself in municipal politics, and eventually developed an interest in lensmaking. Using his handcrafted microscopes, he was the first to observe and describe microorganisms, most of the animalcules are now referred to as unicellular organisms, though he observed multicellular organisms in pond water. He was also the first to document microscopic observations of muscle fibers, bacteria, spermatozoa, Van Leeuwenhoek did not write any books, his discoveries came to light through correspondence with the Royal Society, which published his letters. Antonie van Leeuwenhoek was born in Delft, Dutch Republic, on 24 October 1632, on 4 November, he was baptized as Thonis. His father, Philips Antonisz van Leeuwenhoek, was a maker who died when Antonie was only five years old. His mother, Margaretha, came from a well-to-do brewers family, and remarried Jacob Jansz Molijn, Antonie had four older sisters, Margriet, Geertruyt, Neeltje, and Catharina. When he was ten years old his step-father died. He attended school in Warmond for a time before being sent to live in Benthuizen with his uncle. At the age of 16 he became an apprentice at a linen-drapers shop in Amsterdam owned by the Scot William Davidson. Van Leeuwenhoek left after six years, Van Leeuwenhoek married Barbara de Mey in July 1654, with whom he would have one surviving daughter, Maria. That same year he returned to Delft, where he would live and he opened a drapers shop, which he ran throughout the 1650s. His wife died in 1666, and in 1671, Van Leeuwenhoek remarried to Cornelia Swalmius with whom he had no children and his status in Delft had grown throughout the years. In 1660 he received a job as chamberlain for the Delft sheriffs assembly chamber in the City Hall. Van Leeuwenhoek was a contemporary of another famous Delft citizen, the painter Johannes Vermeer and it has been suggested that he is the man portrayed in two of Vermeers paintings of the late 1660s, The Astronomer and The Geographer. However, others argue that there appears to be little physical similarity, while running his drapers shop, Van Leeuwenhoek wanted to see the quality of the thread better than the then-current magnifying lenses available allowed
8.
Amoeba
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An amoeba, often called amoeboid, is a type of cell or organism which has the ability to alter its shape, primarily by extending and retracting pseudopods. Amoebas do not form a taxonomic group, instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, microbiologists often use the terms amoeboid and amoeba interchangeably for any organism that exhibits amoeboid movement. In older classification systems, most amoebas were placed in the class or subphylum Sarcodina, however, molecular phylogenetic studies have shown that Sarcodina is not a monophyletic group whose members share common descent. Consequently, amoeboid organisms are no longer classified together in one group, the best known amoeboid protists are the Giant Amoebae Chaos carolinense and Amoeba proteus, both of which are widely cultivated and studied in classrooms and laboratories. Amoebae move and feed by using pseudopods, which are bulges of cytoplasm formed by the action of actin microfilaments pushing out the plasma membrane that surrounds the cell. The appearance and internal structure of pseudopods are used to distinguish groups of amoebae from one another, amoebozoan species, such as those in the genus Amoeba, typically have bulbous pseudopods, rounded at the ends and roughly tubular in cross-section. Cercozoan amoeboids, such as Euglypha and Gromia, have slender, foraminifera emit fine, branching pseudopods that merge with one another to form net-like structures. Some groups, such as the Radiolaria and Heliozoa, have stiff, needle-like, free-living amoebae may be testate, or naked. The shells of testate amoebae may be composed of substances, including calcium, silica, chitin, or agglutinations of found materials like small grains of sand. To regulate osmotic pressure, most freshwater amoebae have a contractile vacuole which expels excess water from the cell and this organelle is necessary because freshwater has a lower concentration of solutes than the amoebas own internal fluids. Because the surrounding water is hypotonic with respect to the contents of the cell, without a contractile vacuole, the cell would fill with excess water and, eventually, burst. Marine amoebae do not usually possess a contractile vacuole, because the concentration of solutes within the cell are in balance with the tonicity of the surrounding water, the food sources of amoebae vary. Some amoebae are predatory and live by consuming bacteria and other protists, Some are detritivores and eat dead organic material. Amoebae typically ingest their food by phagocytosis, extending pseudopods to encircle, Amoeboid cells do not have a mouth or cytostome, and there is no fixed place on the cell at which phagocytosis normally occurs. Some amoebae also feed by pinocytosis, imbibing dissolved nutrients through vesicles formed within the cell membrane, the size of amoeboid cells and species is extremely variable. The marine amoeboid Massisteria voersi is just 2.3 to 3 micrometres in diameter, at the other extreme, the shells of deep-sea xenophyophores can attain 20 cm in diameter. Some multicellular organisms have amoeboid cells only in certain phases of life, in the immune system of humans and other animals, amoeboid white blood cells pursue invading organisms, such as bacteria and pathogenic protists, and engulf them by phagocytosis
9.
Scanning electron microscope
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A scanning electron microscope is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the surface topography. The electron beam is scanned in a raster scan pattern. SEM can achieve better than 1 nanometer. Specimens can be observed in vacuum, in low vacuum, in wet conditions. The most common SEM mode is detection of electrons emitted by atoms excited by the electron beam. The number of electrons that can be detected depends, among other things. By scanning the sample and collecting the electrons that are emitted using a special detector. An account of the history of SEM has been presented by McMullan. Ardenne applied the principle not only to achieve magnification but also to purposefully eliminate the chromatic aberration otherwise inherent in the electron microscope. He further discussed the various modes, possibilities and theory of SEM. The types of produced by an SEM include secondary electrons, reflected or back-scattered electrons, photons of characteristic X-rays and light, absorbed current. Secondary electron detectors are standard equipment in all SEMs, but it is rare that a machine would have detectors for all other possible signals. The signals result from interactions of the beam with atoms at various depths within the sample. In the most common or standard detection mode, ie secondary electron imaging or SEI, consequently, SEM can produce very high-resolution images of a sample surface, revealing details less than 1 nm in size. Back-scattered electrons are beam electrons that are reflected from the sample by elastic scattering and they emerge from deeper locations within the specimen and consequently the resolution of BSE images is generally poorer than SE images. BSE images can provide information about the distribution of different elements in the sample, characteristic X-rays are emitted when the electron beam removes an inner shell electron from the sample, causing a higher-energy electron to fill the shell and release energy. These characteristic X-rays are used to identify the composition and measure the abundance of elements in the sample, due to the very narrow electron beam, SEM micrographs have a large depth of field yielding a characteristic three-dimensional appearance useful for understanding the surface structure of a sample
10.
Close-up
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A close-up or closeup in filmmaking, television production, still photography and the comic strip medium is a type of shot, which tightly frames a person or an object. Close-ups are one of the shots used regularly with medium shots. Close-ups display the most detail, but they do not include the broader scene, moving in to a close-up or away from a close-up is a common type of zooming. Most early filmmakers—such as Thomas Edison, Auguste and Louis Lumière and Georges Méliès—tended not to use close-ups and preferred to frame their subjects in long shots, film historians disagree as to which filmmaker first used a close-up. In 1901, James Williamson, also working in Hove, made perhaps the most extreme close-up of all in The Big Swallow, when his character approaches the camera and appears to swallow it. D. W. Griffith, who pioneered screen cinematographic techniques, for example, one of Griffiths short films, The Lonedale Operator, makes significant use of a close-up of a wrench that a character pretends is a gun. Lillian Gish remarked on Griffiths pioneering use of the close-up, The people in the front office got very upset and they came down and said, The public doesn’t pay for the head or the arms or the shoulders of the actor. Let’s give them their money’s worth. ’ Griffith stood very close to them and said, ‘Can you see my feet. ’ When they said no, he replied, I am using what the eyes can see. Close-ups are used in ways and for many reasons. They are often employed as cutaways from a distant shot to show detail, such as characters emotions. Close cuts to characters faces are used far more often in television than in movies, for a director to deliberately avoid close-ups may create in the audience an emotional distance from the subject matter. Close-ups are used for distinguishing main characters, major characters are often given a close-up when they are introduced as a way of indicating their importance. Leading characters will have multiple close-ups, there is a long-standing stereotype of insecure actors desiring a close-up at every opportunity and counting the number of close-ups they received. Close-up shots do not show the subject in the context of its surroundings. If overused, they may leave viewers uncertain as to what they are seeing, Close-ups are rarely done with wide-angle lenses, because perspective causes objects in the center of the picture to be unnaturally enlarged. Certain times, different directors will use wide-angle lenses, because they can convey the message of confusion, there are various degrees of close-up depending on how tight the shot is. The terminology varies between countries and even different companies, but in general these are, Medium Close Up, usually covers the subjects head and shoulders. Close Up, A certain feature, such as someones head, extreme Close Up, The shot is so tight that only a detail of the subject, such as someones eyes, can be seen
