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Sharp Scale
The Sharp Scale was devised by Henrietta Sharp Cockrell as an objective and scientific way to measure the opacity of paper, particularly of manuscript folios, 'in the field' without specialized equipment. A practical application of the technique could be done in a museum or library setting. To apply the method, the folio is first held at a distance of 15 cm from a 60 watt light source (such as an unshaded table lamp). A dowel (or pencil) is held behind and against it, creating a silhouette A silhouette (, ) is the image of a person, animal, object or scene represented as a solid shape of a single colour, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the silhouett .... Folios are then added until the outline of the pencil is no longer visible. The number of the folios needed to obscure the silhouette of the pencil is recorded.Savage-Smith, 2005, p. ??? Notes References * Savage-Smith, Emilie (2005) ...
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Opacity (optics)
Opacity is the measure of impenetrability to electromagnetic or other kinds of radiation, especially visible light. In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc. An opaque object is neither transparent (allowing all light to pass through) nor translucent (allowing some light to pass through). When light strikes an interface between two substances, in general, some may be reflected, some absorbed, some scattered, and the rest transmitted (also see refraction). Reflection can be diffuse, for example light reflecting off a white wall, or specular, for example light reflecting off a mirror. An opaque substance transmits no light, and therefore reflects, scatters, or absorbs all of it. Other categories of visual appearance, related to the perception of regular or diffuse reflection and transmission of light, have been organized under the concept of cesia in an order sys ...
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Folio
The term "folio" () has three interconnected but distinct meanings in the world of books and printing: first, it is a term for a common method of arranging Paper size, sheets of paper into book form, folding the sheet only once, and a term for a book made in this way; second, it is a general term for a sheet, leaf or page in (especially) manuscripts and old books; and third, it is an approximate term for the Book size, size of a book, and for a book of this size. First, a folio (abbreviated fo or 2o) is a book or pamphlet made up of one or more full sheets of paper, on each of which four pages of text are printed, two on each side; each sheet is then folded once to produce two leaf (books), leaves. Each leaf of a folio book thus is one half the size of the original sheet. Ordinarily, additional printed folio sheets would be inserted inside one another to form a group or "gathering" of leaves prior to binding the book. Second, folio is used in terms of page numbering for some bo ...
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Watt
The watt (symbol: W) is the unit of Power (physics), power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantification (science), quantify the rate of Work (physics), energy transfer. The watt is named in honor of James Watt (1736–1819), an 18th-century Scottish people, Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own Watt steam engine, steam engine in 1776, which became fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one meter per second against a constant opposing force of one Newton (unit), newton, the rate at which Work (physics), work is done is one watt. \mathrm. In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the vo ...
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Dowel
The dowel is a cylindrical shape made of wood, plastic, or metal. In its original manufactured form, a dowel is long and called a ''dowel rod'', which are often cut into shorter ''dowel pins''. Dowels are commonly used as structural reinforcements in cabinet making and in numerous other applications, including: * Furniture shelf supports * Moveable game pieces (i.e. pegs) * Hangers for items such as clothing, key rings, and tools * Wheel axles in toys * Detents in gymnastics grips * Supports for tiered wedding cakes Wood dowel Manufacturing process The traditional tool for making dowels is a ''dowel plate'', an iron (or better, hardened tool steel) plate with a hole having the size of the desired dowel. To make a dowel, a piece of wood is split or whittled to a size slightly bigger than desired and then driven through the hole in the dowel plate. The sharp edges of the hole shear off the excess wood.Ivin SickelsExercises in Wood-Working American Book Company, 1889; see ...
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Silhouette
A silhouette (, ) is the image of a person, animal, object or scene represented as a solid shape of a single colour, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the silhouette is usually presented on a light background, usually white, or none at all. The silhouette differs from an line art, outline, which depicts the edge of an object in a linear form, while a silhouette appears as a solid shape. Silhouette images may be created in any visual artistic medium, but were first used to describe pieces of cut paper, which were then stuck to a backing in a contrasting colour, and often framed. Cutting portraits, generally in profile, from black card became popular in the mid-18th century, though the term ''silhouette'' was seldom used until the early decades of the 19th century, and the tradition has continued under this name into the 21st century. They represented a cheap but effective alternative to the portrait m ...
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Savage-Smith, Emilie
Emilie Savage-Smith (born 20 August 1941) is an American-British historian of science known for her work on science in the medieval Islamic world and medicine in the medieval Islamic world. Education and career Savage-Smith was born on 20 August 1941, in the US, and became a dual citizen of the UK and US in 2003. She was an undergraduate at DePauw University, graduating in 1962, and completed her Ph.D. in 1969 at the University of Wisconsin–Madison. Her doctoral dissertation, ''Galen on Nerves, Veins and Arteries'', was a critical edition of book 16 of Galen's '' De usu partium corporis humani'', including a translation from the Arabic edition of Hunayn ibn Ishaq. She is retired as Professor of the History of Islamic Science at the University of Oxford, where she continues to be Fellow Archivist of St Cross College, Oxford and a senior research consultant for the Bodleian Library. She is the president of the Society for the History of Medieval Technology and Science. Before mo ...
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Units Of Measurement
A unit of measurement, or unit of measure, is a definite magnitude (mathematics), magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can be expressed as a multiple of the unit of measurement. For example, a length is a physical quantity. The metre (symbol m) is a unit of length that represents a definite predetermined length. For instance, when referencing "10 metres" (or 10 m), what is actually meant is 10 times the definite predetermined length called "metre". The definition, agreement, and practical use of units of measurement have played a crucial role in human endeavour from early ages up to the present. A multitude of System of measurement, systems of units used to be very common. Now there is a global standard, the International System of Units (SI), the modern form of the metric system. In trade, weights and measures are often a su ...
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Book Arts
Book arts may refer to: * Artist's book, a work of art in the form of a book * Book design, the art of designing a book * Book illustration, illustration in a book * Bookbinding Bookbinding is the process of building a book, usually in codex format, from an ordered stack of paper sheets with one's hands and tools, or in modern publishing, by a series of automated processes. Firstly, one binds the sheets of papers alon ...
, the process of creating a book {{disambiguation ...
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