Who invented Microscope ?

Who invented Microscope ?

By ommics   22:24   No comments:

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 (and the first to be invented) is the optical microscope, which uses light to image the sample. Other major types of microscopes are the electron microscope (both the transmission electron microscope and the scanning electron microscope), the ultramicroscope, and the various types of scanning probe microscope.

The first microscope to be developed was the optical microscope, although the original inventor is not easy to identify. Evidence points to the first compound microscope appearing in the Netherlands by the 1620s, with a likely inventor being Cornelis Drebbel. Counter claims include it being invented by Hans Lippershey (who obtained the first telescope patent) and what may be a dubious claim by Zacharias Janssen's son that his father invented the microscope and telescope. Giovanni Faber coined the name microscope for Galileo Galilei's compound microscope in 1625 (Galileo had called it the "occhiolino" or "little eye").

It was not until the 1660s and 1670s that the microscope was used extensively for research in Italy, the Netherlands and England. Marcelo Malpighi in Italy began the analysis of biological structures beginning with the lungs. Robert Hooke's Micrographia had a huge impact, largely because of its impressive illustrations. The greatest contribution came from Antonie van Leeuwenhoek who achieved up to 300 times magnification. He sandwiched a v. small glass ball lens between the holes in two metal plates riveted together and with an adjustable by screws needle attached to mount the specimen. Then, Van Leeuwenhoek discovered red blood cells and spermatozoa and helped popularise microscopy as a technique. On 9 October 1676, he reported the discovery of micro-organisms.

In the early 20th century a significant alternative to light microscopy was developed, using electrons rather than light to generate the image. Ernst Ruska started development of the first electron microscope in 1931 which was the transmission electron microscope (TEM). The transmission electron microscope works on the same principle as an optical microscope but uses electrons in the place of light and electromagnets in the place of glass lenses. Use of electrons instead of light allows a much higher resolution.

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Who invented NEWS ?

Who invented NEWS ?

By ommics   01:20   No comments:

A newspaper is a serial publication containing news, other informative articles and advertising. A newspaper is usually but not exclusively printed on relatively inexpensive, low-grade paper such as newsprint. The news organizations that publish newspapers are themselves often metonymically called newspapers. Most newspapers are now published online as well as in print. The online versions are called online newspapers or news sites.

Newspapers are typically published daily or weekly. News magazines are also weekly, but they have a magazine format.

General-interest newspapers typically publish news articles and feature articles on national and international news as well as local news. The news includes political events and personalities, business and finance, crime, severe weather, and natural disasters; health and medicine, science, and technology; sports; and entertainment, society, food and cooking, clothing and home fashion, and the arts. Typically the paper is divided into sections for each of those major groupings (labeled A, B, C, and so on, with pagination prefixes yielding page numbers A1-A20, B1-B20, C1-C20, and so on). Most traditional papers also feature an editorial page containing editorials written by an editor, op-eds written by guest writers, and columns that express the personal opinions of columnists, usually offering analysis and synthesis that attempts to translate the raw data of the news into information telling the reader "what it all means" and persuading them to concur.

A wide variety of material has been published in newspapers. Besides the aforementioned news and opinions, they include weather forecasts; criticism and reviews of the arts (including literature, film, television, theater, fine arts, and architecture) and of local services such as restaurants; obituaries; entertainment features such as crosswords, horoscopes, editorial cartoons, gag cartoons, and comic strips; advice, food, and other columns; and radio and television listings (program schedules).

In Ancient Rome, Acta Diurna, or government announcement bulletins, were produced. They were carved in metal or stone and posted in public places.

In China, early government-produced news-sheets, called Dibao, circulated among court officials during the late Han dynasty (second and third centuries AD). Between 713 and 734, the Kaiyuan Za Bao ("Bulletin of the Court") of the Chinese Tang Dynasty published government news; it was handwritten on silk and read by government officials. In 1582, there was the first reference to privately published newssheets in Beijing, during the late Ming Dynasty

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Who invented Telescope ?

Who invented Telescope ?

By ommics   22:09   No comments:

A telescope is an optical instrument that aids in the observation of remote objects by collecting electromagnetic radiation (such as visible light). The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s, by using glass lenses. They found use in both terrestrial applications and astronomy.

Within a few decades, the reflecting telescope was invented, which used mirrors to collect and focus the light. In the 20th century many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. The word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors.

 
The word telescope (from the Ancient Greek τῆλε, tele "far" and σκοπεῖν, skopein "to look or see"; τηλεσκόπος, teleskopos "far-seeing") was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of Galileo Galilei's instruments presented at a banquet at the Accademia dei Lincei. In the Starry Messenger, Galileo had used the term perspicillum.

The earliest recorded working telescopes were the refracting telescopes that appeared in the Netherlands in 1608. Their development is credited to three individuals: Hans Lippershey and Zacharias Janssen, who were spectacle makers in Middelburg, and Jacob Metius of Alkmaar. Galileo heard about the Dutch telescope in June 1609, built his own within a month, and improved upon the design in the following year. In the same year, Galileo became the first person to point a telescope skyward in order to make telescopic observations of a celestial object.

The idea that the objective, or light-gathering element, could be a mirror instead of a lens was being investigated soon after the invention of the refracting telescope. The potential advantages of using parabolic mirrors reduction of spherical aberration and no chromatic aberration led to many proposed designs and several attempts to build reflecting telescopes. In 1668, Isaac Newton built the first practical reflecting telescope, of a design which now bears his name, the Newtonian reflector.

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