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Invisible Ink
Invisible ink, also known as security ink or sympathetic ink, is a substance used for writing, which is invisible either on application or soon thereafter, and can later be made visible by some means, such as heat or ultraviolet light. Invisible ink is one form of steganography. History One of the earliest writers to mention an invisible ink is Aeneas Tacticus, in the 4th century BC. He mentions it in discussing how to survive under siege but does not indicate the type of ink to be used. This was part of his list of the 20 different methods of secret communications in a book called ''On the Defense of Fortifications''. One of the techniques that involved steganography involved puncturing a tiny hole above or below letters in a document to spell out a secret message. This did not include an invisible ink but the Germans improved on the method during World War I and World War II. They used invisible ink and microdots instead of pinpricks. Philo of Byzantium may be the first writer ...
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James Jay
Sir James Jay (October 16, 1732 – 1815) was an Thirteen Colonies, American physician and politician. He was brother of John Jay, one of the Founding Fathers of the United States. While initially a supporter of American independence, he later changed his views becoming a Loyalist (American Revolution), Loyalist and went into exile in London after the Treaty of Paris (1783), Treaty of Paris recognised independence. Early life The Jays were a prominent merchant family in New York City, descended from Huguenots who had come to New York to escape religious persecution in France. In 1685 the Edict of Nantes had been revoked, thereby abolishing the rights of Protestants and confiscating their property. Among those affected was Jay's paternal grandfather, Augustus Jay. He moved from France to New York, where he built a successful merchant empire. Jay's father, Peter Jay, born in New York City in 1704, became a wealthy trader in furs, wheat, timber, and other commodities. James Jay was ...
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Cotton Swab
Cotton is a soft, fluffy Staple (textiles), staple fiber that grows in a wikt:boll, boll, or protective case, around the seeds of the cotton plants of the genus ''Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor percentages of waxes, fats, pectins, and water. Under natural conditions, the cotton bolls will increase the dispersal of the seeds. The plant is a shrub native to tropical and subtropical regions around the world, including the Americas, Africa, Egypt and India. The greatest diversity of wild cotton species is found in Mexico, followed by Australia and Africa. Cotton was independently domesticated in the Old and New Worlds. The fiber is most often Spinning (textiles), spun into yarn or thread and used to make a soft, breathable, and durable textile. The use of cotton for fabric is known to date to prehistoric times; fragments of cotton fabric dated to the fifth millennium BC have been found in the Indus Valley civ ...
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Calligraphy Pen
A dip pen or nib pen or pen nib usually consists of a metal nib with capillary channels like those of fountain pen nibs, mounted in a handle or holder, often made of wood. Other materials can be used for the holder, including bone, metal and plastic; some pens are made entirely of glass. Generally, dip pens have no ink reservoir, so the user must recharge the ink from an ink bowl or bottle to continue drawing or writing. There are simple, tiny tubular reservoirs that illustrators sometimes clip onto dip pens, which allow drawing for several minutes without recharging the nib. Recharging can be done by dipping into an inkwell, but it is also possible to charge the pen with an eyedropper, a syringe, or a brush, which gives more control over the amount of ink applied. Thus, "dip pens" are not necessarily dipped; many illustrators call them "nib pens". Dip pens emerged in the early 19th century, when they replaced quill pens and, in some parts of the world, reed pens. Dip pens were ...
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Toothpick
A toothpick is a small thin stick of wood, plastic, bamboo, metal, bone or other substance with at least one and sometimes two pointed ends to insert between teeth to remove detritus, usually after a meal. Toothpicks are also used for festive occasions to hold or spear small appetizers (like cheese cubes or olives) or as a cocktail stick, and can be decorated with plastic frills or small paper umbrellas or flags. History Known in all cultures, the toothpick is the oldest instrument for dental cleaning. Hominin remains from Dmanisi, Georgia, dated to about 1.8 million years ago, bear lesions indicating the repeated use of a “toothpick”. A Neanderthal man's jawbone found in the Cova Foradà in Spain evidenced use of a toothpick to alleviate pain in his teeth caused by periodontal disease and dental wear. Toothpicks made of bronze have been found as burial objects in prehistoric graves in Northern Italy and in the East Alps. In 1986, researchers in Florida discovered the ...
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Fountain Pen
A fountain pen is a writing instrument which uses a metal nib to apply a water-based ink to paper. It is distinguished from earlier dip pens by using an internal reservoir to hold ink, eliminating the need to repeatedly dip the pen in an inkwell during use. The pen draws ink from the reservoir through a feed to the nib and deposits the ink on paper via a combination of gravity and capillary action. Filling the reservoir with ink may be achieved manually, via the use of an eyedropper or syringe, or via an internal filling mechanism which creates suction (for example, through a piston mechanism) or a vacuum to transfer ink directly through the nib into the reservoir. Some pens employ removable reservoirs in the form of pre-filled ink cartridges. History Early prototypes of reservoir pens According to Qadi al-Nu'man al-Tamimi (d. 974) in his ''Kitab al-Majalis wa 'l-musayarat'', the Fatimid caliph Al-Mu'izz li-Din Allah in Arab Egypt demanded a pen that would not stain his h ...
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Rubber Stamp
A rubber stamp is an image or pattern that has been carved, molded, laser engraved or vulcanized onto a sheet of rubber. Rubber stamping, also called stamping, is a craft in which some type of ink made of dye or pigment is applied to rubber stamp. The rubber is often mounted onto a more stable object such as a wood, brick or an acrylic block. Increasingly the vulcanized rubber image with an adhesive foam backing is attached to a cling vinyl sheet which allows it to be used with an acrylic handle for support. These cling rubber stamps can be stored in a smaller amount of space and typically cost less than the wood mounted versions. They can also be positioned with a greater amount of accuracy due to the stamper's ability to see through the handle being used. Temporary stamps with simple designs can be carved from a potato. The ink-coated rubber stamp is pressed onto any type of medium such that the colored image is transferred to the medium. The medium is generally some type o ...
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Stylus
A stylus (plural styli or styluses) is a writing utensil or a small tool for some other form of marking or shaping, for example, in pottery. It can also be a computer accessory that is used to assist in navigating or providing more precision when using touchscreens. It usually refers to a narrow elongated staff, similar to a modern ballpoint pen. Many styluses are heavily curved to be held more easily. Another widely used writing tool is the stylus used by blind users in conjunction with the slate for punching out the dots in Braille. Etymology The English word ''stylus'' has two plurals: ''styli'' and ''styluses''. The original Latin word was spelled ; the spelling ''stylus'' arose from an erroneous connection with Greek (), 'pillar'.''Oxford Latin Dictionary'', s.v. "stilus" (2012). The Latin word had several meanings, including "a long, sharply pointed piece of metal; the stem of a plant; a pointed instrument for incising letters; the stylus (as used in literary composi ...
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Sodium Bicarbonate
Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation ( Na+) and a bicarbonate anion ( HCO3−). Sodium bicarbonate is a white solid that is crystalline, but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Nomenclature Because it has long been known and widely used, the salt has many different names such as baking soda, bread soda, cooking soda, and bicarbonate of soda and can often be found near baking powder in stores. The term ''baking soda'' is more common in the United States, while ''bicarbonate of soda'' is more common in Australia, United Kingdom and Ireland. and in many northern/central European countries it is called ''Na ...
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Ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to 45% of the world's food and fertilizers. Around 70% of ammonia is used to make fertilisers in various forms and composition, such as urea and Diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products. It is mainly collected by downward displacement of both air and water. Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caust ...
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Constipation
Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement. Complications from constipation may include hemorrhoids, anal fissure or fecal impaction. The normal frequency of bowel movements in adults is between three per day and three per week. Babies often have three to four bowel movements per day while young children typically have two to three per day. Constipation has many causes. Common causes include slow movement of stool within the colon, irritable bowel syndrome, and pelvic floor disorders. Underlying associated diseases include hypothyroidism, diabetes, Parkinson's disease, celiac disease, non-celiac gluten sensitivity, colon cancer, diverticulitis, and inflammatory bowel disease. Medications associated with constipation include opioids, certain antacids, calcium channel blockers, ...
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Phenolphthalein
Phenolphthalein ( ) is a chemical compound with the chemical formula, formula carbon, C20hydrogen, H14oxygen, O4 and is often written as "HIn", "HPh", "phph" or simply "Ph" in shorthand notation. Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in base (chemistry), basic solutions. It belongs to the class of dyes known as phthalein dyes. Phenolphthalein is slightly soluble in water and usually is dissolved in Alcohol (chemistry), alcohols for use in experiments. It is a weak acid, which can lose H+ ions in solution. The nonionized phenolphthalein molecule is colorless and the double deprotonated phenolphthalein ion is Fuchsia (color), fuchsia. Further loss of proton in higher pH occurs slowly and leads to a colorless form. Phenolphthalein ion in concentrated sulfuric acid is orange red due to sulfonation. Uses pH indicator Phenolphthalein's common use is as an indicator in acid-base t ...
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