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Dutch inventions and discoveries

    The Dutch people have a history and tradition in inventing and discovery Dutch scientists and engineers have made a remarkable contribute to human progress as a wholeFrom something as simple as the sawmill to microbiology and artificial organsBelow here is an (incomplete) list of Dutch inventions and discoveries

    Inventions

    The Microscope

    image:Microscope.png|80px|right|Basic microscope main elements:

    1 ocular lens or eye-piece
    2 objective turret or nosepiece
    3 objective lenses
    4 coarse adjustment knob
    5 fine adjustment knob
    6 object holder or stage
    7 mirror
    8 diaphragm and condenserIn 1590 the Dutchmen Hans and Zacharias Janssen (Father and son) invented the first compound microscopeIt would have a single glass lens of short focal length for the objective and another single glass lens for the eyepiece or ocular Modern microscopes of this kind are usually more complex with multiple lens components in both objective and eyepiece assemblies These multi-component lenses are designed to reduce aberrations particularly chromatic aberration and spherical aberration In modern microscopes the mirror is replaced by a lamp unit providing stable controllable illumination

    The Telescope

    Hans Lippershey created and disseminated the first practical telescope Crude telescopes and spyglasses may have been created much earlier but Lippershey is believed to be the first to apply for a patent for his design (beating out Jacob Metius by a few weeks) and make it available for general use in 1608 He failed to receive a patent but was handsomely rewarded by the Dutch government for copies of his design A description of Lippershey's instrument quickly reached Galileo Galilei who created a working design in 1609 with which he made the observations found in his Sidereus Nuncius of 1610
    There is a legend that Lippershey's children actually discovered the telescope while playing with flawed lenses in their father's workshop but this may be apocryphal The son of Zacharias Janssen of Middelburg subsequently testified that Lippershey had stolen the idea for his instrument from his father -at a time when Janssen would have only been two years old
    Lippershey crater on the Moon is named after him

    The Pendulum clock

    A pendulum clock uses a pendulum as its time base From their invention until about 1930 the most accurate clocks were pendulum clocks Pendulum clocks cannot operate on vehicles because the accelerations of the vehicle drive the pendulum causing inaccuracies See chronometer for a discussion of the problems of navigational clocksThe pendulum clock was invented by Christian Huygens in 1656 based on the pendulum introduced by Galileo Galilei
    Pendulum clocks remained the mechanism of choice for accurate timekeeping for centuries with the Fedchenko observatory clocks produced from after WWII up to around 1960 marking the end of the pendulum era as time standards considered
    Pendulum clocks remain popular for domestic use

    The Electrocardiograph

    In the 19th century it became clear that the heart generated electricity The first to systematically approach the heart from an electrical point-of-view was Augustus Waller working in St Mary's Hospital in Paddington London In 1911 he still saw little clinical application for his work The breakthrough came when Willem Einthoven working in Leiden The Netherlands used the string galvanometer invented by him in 1901 which was much more sensitive than the capillary electrometer that Waller used Einthoven assigned the letters P, Q, R, S and T to the various deflections and described the electrocardiographic features of a number of cardiovascular disorders He was awarded the 1924 Nobel Prize for Physiology or Medicine for his discovery

    The Phase contrast microscope

    As light travels through a medium other then vacuum interaction withthis medium causes its amplitude and phase to change in a way whichdepends on properties of the medium Changes in amplitude give rise tofamiliar absorption of light which gives rise to colours when it iswavelength dependent The human eye measures only the energy of lightarriving on the retina so changes in phase are not easily observedyet often these changes in carry a large amount of information
    The same holds in a typical microscope ie although the phasevariations introduced by the sample are preserved by the instrument(at least in the limit of the perfect imaging instrument) thisinformation is lost in the process which measures the light In orderto make phase variations observable it is necessary to combine thelight passing through the sample with a reference so that theresulting interference reveals the phase structure of the sample
    This was first realized by Frits Zernike during his study ofdiffraction gratings During these studies he appreciated both that itis necessary to interfere with a reference beam and that to maximisethe contrast achieved with the technique it is necessary to introducea phase shift to this reference so that the no-phase-change conditiongives rise to completely destructive interference
    He later realised that the same technique can be applied to opticalmicroscopy The necessary phase shift is introduced by rings etchedaccurately onto glass plates so that they introduce the required phaseshift when inserted into the optical path of the microscope When inuse this technique allows phase of the light passing through theobject under study to be inferred from the intensity of the imageproduced by the microscope This is the phase-contrast technique
    In optical microscopy many objects such as cell parts in protozoansbacteria and sperm tails are essentially fully transparent unlessstained (and therefore killed) The difference in densities andcomposition withing these objects however often give rise to changesin the phase of light passing through them hence they are sometimescalled "phase objects" Using the phase-contrast technique makes thesestructures visible and allows their study with the specimen stillalive
    This phase contrast technique proved to be such an advancement inmicroscopy that Zernike was awarded the Nobel prize (physics) in1953

    The Compact disc

    100px
    In the early 1970s using video Laserdisc technology Philips' researchers started experiments with "audio-only" optical discs initially with wideband frequency modulation FM and later digitized PCM audio signals The compact disk was thus developed by Philips from its own 12 inch Philips Laservision disks At the end of the 1970s Philips Sony and other companies presented prototypes of digital audio discs
    In 1979 Philips and Sony decided to join forces setting up a joint task force of engineers whose mission was to design the new digital audio disc Prominent members of the task force were Kees Immink and Toshitada Doi After a year of experimentation and discussion the taskforce produced the "Red Book" the Compact Disc standard Philips contributed the general manufacturing process based on the video Laserdisc technology Philips also contributed the Eight-to-Fourteen Modulation EFM which offers both a long playing time and a high resilience against disc handling damage such as scratches and fingerprints; while Sony contributed the error-correction method CIRC The Compact Disc Story told by a former member of the taskforce gives background information on the many technical decisions made including the choice of the sampling frequency playing time and disc diameter According to Philips the Compact Disc was thus "invented collectively by a large group of people working as a team"[1]

    The Sawmill

    Cornelis Corneliszoon (Born 1550 in Uitgeest - died 1600) was the inventor of the sawmillPrior to the invention of sawmills boards were rived and planed or more often sawn by two men with a whipsaw using saddleblocks to hold the log and a pit for the pitman who worked below and got the benefit of the sawdust in his eyes Sawing was slow and required strong and enduring men The topsawer had to be the stronger of the two because the saw was pulled in turn by each man and the lower had the advantage of gravity The topsawyer also had to guide the saw so the board was of even thickness This was often done by following a chalkline
    Early sawmills simply adapted the whipsaw to mechanical power generally driven by a water wheel to speed up the process The circular motion of the wheel was changed to back-and-forth motion of the saw blade by a pitman thus introducing a term used in many mechanical applications A pitman is similar to a crankshaft but used in reverse A crankshaft converts back-and-forth motion to circular motion
    Generally only the saw was powered and the logs had to be loaded and moved by hand An early improvement was the development of a movable carriage also water powered to steadily move the log through the saw blade

    The Road-rule enforcement camera

    Gatso
    speed camera
    Dutch company Gatsometer BV founded by the 1950s rally driver Maurice Gatsonides invented the first road-rule enforcement cameras Gatsonides wished to better monitor his speed around the corners of a race track and came up with the device in order to improve his time around the circuit [2] The company developed the first radar for use with road traffic and is the world's largest supplier of speed camera systems Because of this in some countries speed cameras are sometimes referred to as "Gatsos" They are also sometimes referred to as "photo radar" even though many of them do not use radar
    The first systems introduced in the late 1960s used film cameras to take their pictures From the late 1990s digital cameras began to be introduced Digital cameras can be fitted with a modem or other electronic interface to transfer images to a central processing location automatically so they have advantages over film cameras in speed of issuing fines and operational monitoring However film-based systems still generally provide superior image quality in the variety of lighting conditions encountered on roads and in some jurisdictions are required by the courts due to the ease with which digital images may be modified New film-based systems are still being sold

    The Leyden jar

    ]The Leyden jar was the original capacitor developed by Pieter van Musschenbroek in the 18th century and used to conduct many early experiments in electricityThe device was a glass jar coated inside and out with metal The inner coating was connected to a rod that passed through the lid and ended in a metal ball Typical designs consist of an electrode and a plate each of which stores an opposite charge These two elements are conductive and are separated by an insulator (eg the glass dielectric) The charge is stored at the surface of the elements at the boundary with the dielectric

    The pyrometer

    The pyrometer invented by Pieter van Musschenbroek is a temperature measuring device which may consist of several different arrangements
    A simple type of pyrometer uses a thermocouple placed either in the furnace or on the item to be measured The voltage output of the thermocouple is read from a digital or analog meter calibrated in degrees Celsius (C) or Fahrenheit (F) There are many different types of thermocouple available and these can be used to measure temperatures from -200 degrees C to above 1500 degrees C.
    The term can also be applied to the so-called optical pyrometer a class of non-contact instruments measuring temperatures above 600 degrees Celsius These are typically used to measure temperatures of glowing hot metals in a steel mill or foundry
    One of the most common non-contact pyrometers is the absorption-emission pyrometer which is a thermometer for determining gas temperature from measurement of the radiation emitted by a calibrated reference source before and after this radiation has passed through and been partially absorbed by the gas Both measurements are made over the same wavelength interval

    The Submarine

    Cornelius Drebbel was the inventor of the first navigable submarine while working for the British Navy Using William Bourne's design from 1578 he manufactured a steerable submarine with a leather-covered wooden frame Between 1620 and 1624 Drebbel successfully built and tested two more submarines each one bigger than the last The final (third) model had 6 oars and could carry 16 passengers This model was demonstrated to King James I in person and several thousand Londoners The submarine stayed submerged for three hours and could travel from Westminster to Greenwich and back cruising at a depth of from 12 to 15 feet (4 to 5 metres) This submarine was tested many times in the Thames but never used in combat

    The artificial kidney

    An artificial kidney is the machine and its related devices which allow to clean the blood of patients who have a temporary (acute) or an ongoing (chronic) failure of their kidneys The procedure of cleaning the blood by this means is called dialysis a type of renal replacement therapy which is used to provide an artificial replacement for lost kidney function due to renal failure It is a life support treatment and does not treat any kidney diseasesDialysis may be used for very sick patients who have suddenly lost their kidney function (acute renal failure) or for quite stable patients who have permanently lost their kidney function (end stage renal failure)When healthy the kidneys remove waste products (for example potassium acid and urea) from the blood and also remove excess fluid in the form of urine Dialysis treatments have to duplicate both of these functions as dialysis (waste removal) and ultrafiltration (fluid removal)

    Discoveries

    Bacteria

    The first bacteria were observed by Anton van Leeuwenhoek in 1676 using a single-lens microscope of his own design The creatures he saw were desribed as 'kleine diertjens' Old Dutch for small creatures The name bacterium was introduced much later by Ehrenberg in 1828 derived from the Greek word βακτηριον meaning "small stick" Because of the difficulty in describing individual bacteria and the importance of their discovery to fields such as medicine biochemistry and geochemistry the history of bacteria is generally described as the history of microbiology

    spermatozoi

    A spermatozoon or spermatozoan (pl spermatozoa) from the ancient Greek σπερμα (seed) and ζων (alive) and more commonly known as a sperm cell is the haploid cell that is the male gamete It joins an ovum to form a zygote A zygote can grow into a new organism such as a human being genetic information to the diploid offspring In mammals the sex of the offspring is determined by the sperm cells: a spermatozoon bearing a Y chromosome will lead to a male (XY) offspring while one bearing an X chromosome will lead to a female (XX) offspring ( the ovum always provides an X chromosome) Sperm cells were first observed by a student of Antoni van Leeuwenhoek in 1677

    infusoria

    Infusoria is a collective term for minute aquatic creatures like ciliate euglena paramecium protozoa and unicellular algae that exist in freshwater pond water However in formal classification microorganism called infusoria belongs to Kingdom Animalia Phylum Protozoa Class Ciliates (Infusoria)They were first discovered by Antoni van LeeuwenhoekAmongst Van Leeuwenhoek's many discoveries are: In 1674 he discovered infusoria (dated zoölogical category) in 1676 he discovered bacteria in 1677 he discovered spermatozoi and in 1682 he discovered the banded pattern of muscular fibers

    Plant respiration and photosynthesis

    The primary site of photosynthesis in plantsPhotosynthesis and plant respiration is an important biochemical process in which plants algae and some bacteria convert the energy of sunlight to chemical energyThe process was discovered by Jan Ingenhousz in 1779 The chemical energy is used to drive synthetic reactions such as the formaton of sugars or the fixation of nitrogen into amino acids the building blocks for protein synthesis Ultimately nearly all living things depend on energy produced from photosynthesis for their nourishment making it vital to life on Earth It is also responsible for producing the oxygen that makes up a large portion of the Earth's atmosphere Organisms that produce energy through photosynthesis are called photoautotrophs Plants are the most visible representatives of photoautotrophs but it should be emphasized that bacteria and algae also contribute to the conversion of free energy into usable energy

    The Rings of Saturn

    The rings of Saturn are a series of planetary rings that orbit the planetSaturn They consist largely of ice and dust
    Galileo Galilei was the first person to observe Saturn's ring in 1610 althoughwith his weak telescope he could barely resolve them and thought they were two moons oneither side of the planet In 1655 Christian Huygens was the first person to propose that there was a ringsurrounding Saturn

    Australia

    Hollandia Nova 1659
    map prepared by Joan Blaeu based on voyages by Abel Tasman and Willem Jansz this image shows a french edition of 1663The first undisputed sighting of Australia by a European was made in 1606 The Dutch vessel Duyfken captained by Willem Jansz followed the coast of New Guinea missed Torres Strait and explored perhaps 350km of western side of Cape York in the Gulf of Carpentaria believing the land was still part of New Guinea [3] The Dutch made one landing but were promptly attacked by Aborigines and subsequently abandoned further exploration
    The discovery that sailing east from the Cape of Good Hope until land was sighted and then sailing north along the west coast of Australia was a much quicker route than around the coast of the Indian Ocean made Dutch landfalls on the west coast inevitable Most of these landfalls were unplanned The first such landfall was in 1616 when Dirk Hartog landed on what is now called Dirk Hartog Island off the coast of Western Australia and left behind an inscription on a pewter plate (This plate may now be seen in the Rijksmuseum in Amsterdam) The most famous and bloodiest result was the mutiny and murder that followed the wreck of the Batavia
    Further voyages by Dutch ships explored the north coast of Australia between 1623 and 1636 giving Arnhem Land its present-day name In 1642 Abel Tasman sailed on a famous voyage from Batavia (now Jakarta) to Papua New Guinea Fiji New Zealand and on November 24 sighted Tasmania He named it Van Diemen's Land after Anthony van Diemen the Dutch East Company]'s Governor General at Batavia who had commissioned his voyage Tasman claimed Van Diemen's Land for the Netherlands In 1644 he made a second voyage [4] on which he mapped the north coast of Australia from Cape York westward [5] Other notable Dutch explorers of the Australian coast include François Thyssen [6] (with Pieter Nuyts on board [7]) who discovered much of the south coast in 1627 [8] and Willem de Vlamingh [9] who mapped the west coast in 1696-1697 [10]