RHETORIC in DESIGN -issues for design -16

Post 653 -by Gautam Shah

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Rhetoric is the ‘art of speaking or writing effectively’. (Webster’s Definition) Aristotle describes it as ‘the ability or means of persuasion’. He describes three forms of rhetoric: Ethos (distinctive spirit of a people or an era), Logos (the logic and supportive evidence behind an argument or a reasoned discourse), and Pathos (represents an appeal to the emotions of the audience, and elicits feelings that already resides in them). Rhetoric is used in literary and verbal expressions, by using things that are familiar, but less acknowledged in common usage. In literary and verbal expressions rhetoric is exploited by construction (of the language form) and reinforced through the means of delivery such as rendering diction and graphics.

458px-Sanzio_01_Plato_Aristotle

Literary and verbal expressions generate instant and consistent impression over their audience or followers. Designed objects like arts, crafts, architecture, graphics, products, etc. however, do not carry an immediate or intense message of persuasion. A design has a persistent delivery, but very variable in content. It gets actualized in many different scenarios.

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Emotions through rhetoric ‘have specific causes and effects’ (Aristotle -book 2.1.2–3). Such dialogues however, do not exist between designers and connoisseurs. ‘Aristotle posits that along with the pathos (an appeal to the emotions of the audience), a speaker must also deploy good ethos (distinctive spirit of a people or an era) in order to establish credibility’. Philo distinguishes between two different types of logos 1 Prophorikos (the uttered word) and 2 Endiathetos (the word remaining within). In case of design-objects, the later one is relevant, as the rhetoric of design is always latent or potential.

640px-Henri_Rousseau_(French)_-_A_Centennial_of_Independence_-_Google_Art_ProjectRhetoric is means of expression or conveyance. In Literature and utterances it gets reinforced through linkages or examples, and altered through feedback from the audience. Such immediate response is not possible for Art, craft or architecture, and if any, it arrives as feed-forward in the make up (training and experience) of the creator. The design feed-forward chiefly relies on the visual rhetoric like books, site visits, media images, etc. But, it is impossible to perceive here ‘one cause to one effect pattern’. Other sensorial inputs like touch, smell, taste, aural, etc., historically had alogical legitimacy. Once a design actualizes, the feedbacks may arrive as historical realizations, but in different time and context. So designs can ‘have traceable past, but uncertain future.

Interior_of_a_revolving_space_station_(artwork)

It is often claimed that visual literacy is of recent origin, when we ignore the mediums of expression and conveyance, which have been with us since primitive age. Wall murals’ images were visual rhetoric, well ‘read’ and capable of arousing Aristotelian pathos (an appeal to the emotions of the audience). Some examples of visual means are charts, graphs, diagrams, photographs, movies, printed media, etc. but though these arouse the pathos but not always as instant response.

640px-Graffiti_in_London

Visual Literacy

The study of visual rhetoric is different from that of visual or graphic design, in that it emphasizes images as sensory expressions of cultural meaning, as opposed to purely aesthetic consideration. (Kress, Gunther, and Theo van Leeuwen. Reading Images: The Grammar of Visual Design. New York: Routledge, 1996.).

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The Design objects like architecture poses a statement only after their making, or on being used as an ‘artifact. Vitruvius stated that a work of architecture is a matter of ‘invention, arrangement, memory, delivery, and style’, and the process was perceived to be similar, to the Aristotelian way of putting together a speech. Design creation is very circumstantial, meant for a client, functions, site, regulatory framework, financial restraints, etc. It, however, needs to be tempered by arrangement, assimilation or composition of many different elements and considerations. These, together offer a holistic character, but realizable only after the creation. Rhetoric in design, if any, is in the design feed-forward, and after its avatar through the feedback. The feed back spreads over a very long period, sometimes after the original entity is destroyed. The Aristotelian depiction of Rhetoric as ‘the ability or means of persuasion’, for designed objects like architecture remains vague or conjectural.

Bidri_craft,_craftmen_at_work

The ability or means of persuasion were reasonable for artefacts conceived and made by the same person. But modern designers generate designs through surrogates or representations, and transmitted to makers or assemblers as schema or specifications. The communication through a schema is an order for execution, but certainly not for persuasion or concurrence. The instructions, if, any are non-personal and distanced in time. Some designs are too involved with the clients or stake-holders, but many others are panoptic. Designers are self-absorbed to care for persuasion or confirmation of anyone. Rhetoric exists, but as statement of non-confirmation.

Deconstruction Ways by Isidro Blasco

Design disciplines are categorized in four major domains: Graphic Design (Real and abstract -symbols communication), Products Design (objects, artefacts, craft-items), Services Design (software, interaction, stake holders) and Empathetic Design (social concerns).

McKeon, Buchanan state the understanding of design, as of symbols and images1, physical artifacts2, actions and activities3, and environments or systems4.

Architecture Confluence Lyon Deconstruction

Build-Designs are perceived at Two levels. First level consists of assembly of elements like signs, patterns, or images, and the organizational discipline. At another level, there is holistic form that is conceived without any elemental identities.

Kirtimukha_sculptures_on_shikhara_(tower)_of_Amrutesvara_temple_at_AmruthapuraThere are few characteristics common to both the congregated and totalitarian forms. Design, in part or as a whole is an allusion to something separated in time and space, and formed through analogy (comparison) or antithesis (contrast). Antiphrasis is an impressionistic expression to convey non-conventional meaning used for sarcasm. Build-forms or the constituents are given magniloquence by way of exaggerated scale, contrasts, precarious shape and intensive vibrancy.

Bilbao,_Euskal_Herria_-_panoramio_(1)

There are few features that rhetorize composite forms due to multiplicity of constituents elements. The sub-elements occur as microcosm, recurrence, as directional move, evolution-devolution and support-contrast. These rhetoric elements manifest in scaling, sequencing or within a perceptible domain of time or spatial reference.

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Design objects like architecture, fashion, products, are created for stake-holders and for personal gratification. Objects for personal gratification often result from intense desire to go out of the box as a non-conformal creative activity. This attitude, though very radical, resulting into unusual approaches and solutions, is tied to reality. All worldly creations are governed by factors like gravity, terrain and environment. Arguments of persuasion, justification or acceptance.

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Out of the Box thinking: It is believed, the term for unconventional perspective in thinking, has come from British mathematician Henry Ernest Dudeney. In this, nine dots are to be interconnected by using four lines drawn without the pencil leaving the paper. The puzzle required one to go beyond the dot array boundaries that is move out of the box.

9Dot puzzle

 

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This is the 16 th article of 20 topics series on ISSUES for DESIGN

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MEANING of CRAFTS -5 -TOOLS

Post 651 -by Gautam Shah

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Villeneuve_d'Ascq_Eté2016_Asnapio_(35)

Tools are implements used by a person in manual operations for production or processing, like manipulation materials, craft-work, building construction, cultivation, food processing, offense-defence, handling, carriage, measurement and expression (writing, drawing, enacting). Tools have been used for making better tools. Tools are for doings things in an easier manner, as well as for doings things that otherwise would not have been possible by hands. There are few conditions where instead of the tools, the supports and other facilitatory structures and arrangements help in creative efforts and productivity.

Stone Age Caveman Ancestor Hunting Neanderthal

Tools are universal implements, used over different tasks and materials. Over a time, though, an exclusive manner of handling develops. The manner of handling evolves a holding mechanism. The holding mechanism, an entity integral with the tool, allowed efficient use of the tool. The combination of a tool and its handling mechanism was a task (and material) specific facility. The tools and handling section, each served different purposes, and so were shaped accordingly. Both faced different stresses and required different composition. But a combination of diverse forms and materials need to be compatible, coordinated and well joined.

Stone_tools_from_Jebel_Irhoud

 

Handled tools extend and modify the reach of the body. The extended reach helps remote access, adds to leverage and allows torque or twisting. For cutting, breaking, beating, copping and such other jobs need leverage for impact or percussive forces.

Stone Age Tomahawk Blue Archaic Close Hoe Sky

A lever amplifies an input force to provide a greater output force. The lever arm is defined as the perpendicular distance from the axis of rotation to the line of action of the force.

Recognizing objects that can work more efficiently was the first craft. Refining by reshaping natural objects for a specific purpose has been one of the oldest craft industries. Some of the basic craft tools were for food preparation, and personal safety and security. Early tools were fragile and often got consumed in the use-processes. And so, the search for new tools was everlasting, alternatively new tools had to be fashioned from old ones. Redefining the tools necessitated search for better materials, sharpening the edge, and tying a handle.

640px-Adzes_from_New_GuineaTools were now of three basic classes: hand-held tools, percussive tools and projectiles. Other sub-classes were like cutting, scrapping, hole making, vessels, holding, measuring, coating-spreading, digging, mixing, etc.

Haljesta

Primary tool materials were stones, woods, bones, clays and perhaps metals. Some of these could be re-formed by downsizing. Clay and metals were plastic materials that could be re-formed by moulding and additive process.

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Holding tools became important for two main purposes, to hold fine-sized objects and tools and to hold fire or hot things. Fine items like beads, and precious-stones need to be held properly to work upon them. Tool bits like fine and fragile edges need support, whereas fine points for drilling and engravings require adequate gripping. Tools were required to initiate, and work with fire. These included fire-fuel management utilities (chulhas), air blowers, handle for hot tools and holders for vessels. Agriculture related tools like thresher boards, winnowing baskets, sieves, land tillers, etc. Spinning, knitting, and weaving utilities developed for threads and cordage, which were used for binding handles, roof and wall elements, fishing nets, etc.

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Tools, as said earlier, are handy things. But there are many utilities, facilitatory structures and arrangements that have helped creative efforts and productivity. In these, at certain level of detail tools like appendages or similar advantages are invested. One of the first ones was the fireplace that contained the fire, helped efficient use of the fuel and offered resting stands for things to be heated. Similarly structures were created as dwelling spaces, clothes or apparel, shoes, head caps, adornments, toys, totems, murals, shutter systems over openings, hangers for food to protect it from insects and rodents, sleeping mats, hammocks and cradles, lamps that evolved less heat but more light, food grinding stones, narrow neck pitchers for liquid storage, slide for transporting goods, etc.

640px-Göbekli_Tepe,_Urfa

At some level the tools, utilities, facilitatory structures and arrangements were merged as devices, machines, apparatuses, equipments or plants. These were integrated with the built-forms, for support, location-based advantage or task setting. The tool, craft and technology were one seamless pursuit. The pursuit also integrated several materials into not only single purpose entities but very specialized task facilities. The task related specializations also created technology-based castes, guilds and communities. The craft communities are tied to terrains and climates. This allows them to develop acutely ethnic styles.

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COPPER -1

Post 477 –by Gautam Shah

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Pure copper nodule 40 mm across

Copper resources of the world are estimated at nearly 5.8 trillion pounds. Of these only about 0.7 trillion pounds have been mined to date. The recycling and recovery rates of copper are so high that of nearly all of the copper mined throughout history, is still in circulation today. This means nearly 80 % of all copper ever mined is still in use today.

Malachite, Zaire> Uploaded by JJ Harrison

Copper was discovered by prehistoric man, in search of shiny stones that when beaten did not break down but rather flattened out. This was sensational discovery leading to search of shiny nodules across lands. Pure Gold and Copper nodules were forged into items of adornments and tools. It was known that several nodules of such pure metals could be forged to form a larger piece. Such nodule findings were rare. But two forms of copper carbonates greenish malachite and bluish azurite were easy to identify and collect from the grounds. Malachite was also used as a gemstone. Similarly many other bright minerals were identified.

Neoclassical vase in malachite in the Hermitage Museum, St Petersburg Uploaded by Dezidor

Azurite 80 x 60 mm Azuritechessy.jpg Uploaded by Archaeodontosaurus

Copper was known around 10000 BC or even earlier. Earliest copper object, a pendant dating 8700 BC, was found Iraq. Copper, in natural nodules form, remained a prized material for a while, but soon became a metal of utility. Unalloyed copper is soft for tools and weapons, but fairly suitable for shaping of utensils. Mesopotamia and Egypt exploited copper for creating tools used in farming, wood working, cooking, etc. These were hoes, adzes, saws, combs , pots, dishes, chisels, harpoons, cloak-pins etc. By 6000 BC it was realized that, although copper was not amenable to casting, it could be worked by hammering, chasing, engraving, and cold-rolling. Sumerians used copper sheets to form sculptures over wooden forms and fastened on walls with copper nails or wires set in bitumen.

Imdugud (also Zu or Anzu), the lion-headed eagle; Sumerian metalwork (sheets of copper), Temple of Ninhursag at Tell al-‘Ubaid; ca. 2500 BC

The Roman supply of copper almost entirely came from Cyprus, and so was known as metal of Cyprus, shortened to cyprium, later corrupted to cuprum. Copper is found at many locations as a primary mineral in basaltic lavas and also as reduced form of copper compounds. It occurs in combination with many minerals, such as chalcocite, chalcopyrite, bornite, cuprite, malachite, and azurite. It is an extremely ductile and malleable metal with high tensile strength. It is an excellent conductor of heat and electric. It is a very noble metal and by acting as a cathode can corrode other contagious metals except stainless steel. It is resistant to most acids and sea water.

Bronze decoration

A Copper alloy with tin is known as bronze. Bronze is a stronger alloy, and harder than both the pure metals. Bronze can be cast. A copper with zinc is called Brass. It was also known that by hammering the copper became hardened, ideal for creation hard edged tools. Copper and its alloys, bronze and brass, mark the first science revolution of man. However, relative scarcity of tin in many regions of the world did not allow use Bronze equally everywhere. Tin-based bronzes were preferred due to the hazard of arsenic poisoning from fumes produced by the oxidation of arsenic-containing minerals. Copper-arsenic alloys, of superior properties to copper in both cast and wrought form, were produced in many regions. Arsenic contents varied from 1 to 7 percent, with up to 3 percent tin. In many civilizations the production of pure copper, arsenical copper, and tin bronze continued together for some time.

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ART COATINGS

Post 432 – by Gautam Shah

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Lascaux2

Coatings are thin surface finishing techniques. A thin film is achieved by using a material that is in a liquid state or is convertible into a liquid phase. A coating may or may not have a colourant, but on drying achieves various degrees of transparencies. Coatings are applied to entities to alter the appearance, improve the tangibility and to provide a protective cover. Historically, however, coatings have been used for illustration and decorative effects.

The discovery of mixing dishes suggests that liquid pigment mixed with fat was also used and smeared with the hand. The subtle tonal gradations of colour on animals painted in the Altamira and Lascaux caves appear to have been dabbed in two stages with fur pads, natural variations on the rock surface were exploited to create the effects of volume.

Sleeping_Antelope_Tin_Taghirt

The simplest way of marking cave walls was to make finger-traces in the soft layer of clay covering the rock. Lime stone walls were engraved and filled in with iron oxide (hematite, or ochre), or the black pigment as manganese or charcoal. These materials were usually available locally. Analyses of pigments, reveal the use of extenders such as talc or feldspar, to increase the bulk of pigments. It also shows traces of animal and plant oils, used for binding. The pigment in paste form was applied with fingers, and also tools like animal-hair brushes or crushed twigs. Lumps of pigment discovered on cave floors may have been used as crayons, but since they do not mark the rock well, they were more likely to be sources of powder. Colour was often sprayed, from the mouth or through a tube. A network of ladder, supports and scaffolding was used to reach the ceilings and upper portions of walls. Light was provided by hearths, or portable burning torches.

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Primitive coatings were daubing of clays, minerals, charcoal, lamp blacks often mixed with mediums such as water, tallow, vegetable excretion and juices, urine, blood, bitumen. Binding mediums were employed to fix the mineral or colourant particles on the surface. Some of the binding mediums were evaporative and worked only as a `leveller’ for particulate matter. By 6000 BC, in China, calcined (fired) mixtures of inorganic compounds and organic pigments and binding mediums (vehicles) were prepared from gum arabic, egg white, gelatin, and beeswax.

Some oily mediums though superior in fixing and longer lasting, but collected dust on aging. Oil mediums became darker in colour due to oxidation, or just peeled off. Some of the mediums were destroyed due to fungus and algae. Later little more complex substances such as starches of rice and maize, pine wood extracts, egg albumin, bees wax, hydrated limes, gypsum, etc. were used.

PREHISTORIC ART FORMS

There are basic TWO sets of Arts. Fixed arts are built-forms, wall murals and architectural embellishments. These could have been part of either exterior and interior environments. Portable arts, comprise of objects or artefacts. These usually remained in protected environments. Fixed arts were largely painted and scratched or engraved, but portable arts had, at least in initial periods, natural finishes by way of selection and production processes.

Venus_vom_Hohlen_Fels_Original_frontal

Portable arts consist of wide variety of object forms and material combinations. Compared to the fixed Arts the objects are smaller in size. The portable objects show all, the surface treatments, embellishments and coating applications. The objects of this category show greater integration of all the three interventions and greater detail or involvement. Large number and wide variety of objects have been preserved and recovered even from regions where Fixed Arts entities have not survived. Portable arts’ objects are smaller and personal hobby or a family craft creation. The colour and surface quality were matter of choice or discoveries through innovation in production.

Paulnabrone

Fixed Arts entities that have survived are surface treatments or renderings through show painting, scratching, engraving and daubing methods. On the other hand, the surviving built-forms, if considered as art-forms, represent technological milestones of material handling, supporting and construction planning. Fixed arts were large scale or important societal activities, involving entire community by way of voluntary participation or forced labour. The involvement of the community was for seasonal or occasional rituals. The leader, conductor or priest of the ritual and the team were the select few experts who initiated and updated the (art) entities over and over again. Such art-forms indicate occupation or interventions of several generations, as much as for more than 300 years.

Bradshaw rock paintings

Portable Art objects are incidental that is the availability, shape, size, colours, texture, etc. define the range of treatments. Many times the purpose it will serve evolves during the process of treatments. Such objects show material combinations. many different finishes were achieved, by change of forms and exploiting the tools. Material processes like heating, singeing, sintering, baking, beating, shaping, cutting, chopping, grinding, drilling, etc., were also used in farming and cooking. It was one seamless manner of learning.

Venus_of_Brassempouy

The materials were stones, precious stones, metal nodules, mineral and other colourants, woods, grasses, twigs, hides, leathers, skins, furs, hairs, shells, teeth, horns, bones, ivory, raw clay objects, baked clay ceramics, seeds, fruits, etc.

The objects formed were totems, body adornments, tools, implements, ritual and burial objects, cooking utilities, toys for children, amenities and dwelling embellishments.

Collier_de_Penne

These were exchanged, gifted to others or offered in rituals. The objects began to have consistent expressions. The varied metaphors, passing from one generation to other, ultimately became abstract. Coins, plaques, seals, etc. represent multiple conversions of expressions like a language.

Ggantija_Temples,_Xaghra,_Gozo

Fixed Art objects like built-forms, though functional utilities were built for community and for political purposes.

The public use entities were irrigation facilities, forest clearance, dykes, bridges, walks or passages, drinking water resources, community surround structures, security amenities and storage arrangements. These were not ‘decorative arts’ but symbolized technological innovations. Some like burial stones and dolmen had items of personalization.

Cave_Paintings_Bhembetika_(22)e

Fixed Arts objects like wall arts show skills of surface preparation, rendering or painting and surface finishing. These creations also show art of surface preparation by way of grinding, etching, daubing, engraving and colourant application. Wall-arts exist in odd narrow corners, at very high elevations, tall ceilings, day time dark corners and in nearly inaccessible places. The effort must have required support structures, bridges, scaffolds, illumination and ancillary works to protect the creations from moisture.

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COLOURS -Perception and Expression

Post 356 –  by Gautam Shah 

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Colours have two relevancies. Some consider colour perception as biological phenomena, common to all human beings. Others perceive colour to be variable with social and a cultural facet. The social and cultural affectations of colour are observed in linguistic, ethnic, and aesthetic expressions.

Colouring_pencils

Perception of a colour, even if, a biological phenomena, one needs to convey that experience, usually by specifying the Hue and Tone of the colour. This may be done by comparison to some other colour of near hue and tone, and also by naming it in distinctive way.

Rangoli,kolam,chennai,Tamil_Nadu382

Nearly all languages unambiguously describe the black and white. Such unequivocal terms exist for few other colours, but not all shades. The third definitive term is for Red and fourth term could be either Green or Yellowbut not both simultaneously. The fifth definition may include either the Green or Yellow (excluded from fourth choice). The next, seventh descriptive choice is Blue. Other preferences in the choice sequence are for Brown, Purple, Pink, Orange, Gray.

Additive and Subtractive colours

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Colours definitions other then these (11 or 12) common terms across different languages are more likely to be comparative idioms such as reddish, irrational value judgements like darkie or lighter, cool and warm tones. Metal and many materials have direct colour associations such as gold, silver, ash, orange (tangerine), KumKum (vermilion red), Turmeric (Haldi), etc.

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The variations in colour terms across regions (cultures-languages) pose a different picture. In spite of scientific spectrum definitions, the cultural recognition and acceptance do not match.

Mountain-spring-redwhite

There was virtual lack of colour terminology in Homeric Greek literature, but it does not mean the Greeks could not perceive the colours as we do it now. We can now differentiate and define nearly 2.4 Mn colours. To distinguish a specific colour one needs to reference it in terms of hue, saturation, luminosity of the light, and context (contrast, background, reference -mental recall or spectrum definition).

Colour tonal variations Wikipedia Image by Phlake at en.wikipedia

We perceive colours and talk about it in entirely different context. We express colours through objects, surfaces, paintings, scenes, nature, fire, water, reflections, shadows, television, films, and other media. We also perceive colours with light and shade, textures, gloss, patterns, perspective, angle of vision, silhouette, visual aberrations and make-believe effects. In each case our connection with the colour is personal, and to recollect and replicate that experience into a scientifically coded vocabulary is difficult.

“The intensity of a spectral colour, relative to the context in which it is viewed, alters its perception  a low-intensity orange-yellow seems brown, and a low-intensity yellow-green looks  olive-green.”

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ALABASTER

Post 275 –by Gautam Shah

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Lioness_Bast_cosmetic_jar_83d40m_tut_burial_artifactAlabaster has been used for decorative objects since 3500BC. It is believed that one of the sources for Alabaster was Alabastron, a town in Egypt. The Greek mineral name alabastrites is derived from that town. The word alabaster relates to Greek –alabastros or alabastos, and old French –alabastre. Alabaster also connects to ancient Egyptian word a-labaste that refers to vessels of the Egyptian Goddess Bast.

ValenciaCathedral2

‘Calcite, like most carbonates, will dissolve with most forms of acid. Calcite can be either dissolved by groundwater or precipitated by groundwater, depending on several factors including the water temperature, pH, and dissolved ion concentrations. Although calcite is fairly insoluble in cold water, acidity can cause dissolution of calcite and release of carbon dioxide gas. Ambient carbon dioxide, due to its acidity, has a slight solubilizing effect on calcite. Calcite exhibits an unusual characteristic called retrograde solubility in which it becomes less soluble in water as the temperature increases. When conditions are right for precipitation, calcite forms mineral coatings that cement the existing rock grains together or it can fill fractures. When conditions are right for dissolution, the removal of calcite can dramatically increase the porosity and permeability of the rock, and if it continues for a long period of time may result in the formation of caves. On a landscape scale, continued dissolution of calcium carbonate-rich rocks can lead to the expansion and eventual collapse of cave systems, resulting in various forms of karst topography’. (from Wikipedia).\

490px-MorellaSantaMariaWindowAlabaster is translucent whitish kind of gypsum. It is a soft and easy to work or carve material used for making vases, ornaments, bottles, jars, busts and ornamental objects. A three-foot vase with a relief from Warka, of 3500-3000 BC (in British Museum), busts from Sumer, of 3000 BC (Louvre), ornate triple lotus oil lamps found in the Tomb of Tutankhamen 1356 BC, and Sarcophagus of Seti I 1304 BC, are some ancient items made of alabaster. Decorative artefacts of Alabaster have been found in Sumer, Babylonia, Assyria and Roman empire. In later periods it was used in India from 6th to 13th C.

640px-Alabaster_Bazylika_JG

Ancient Egypt alabaster vessels Florence

Alabaster are broadly two classes of minerals, a sulphate of lime or a pure variety of gypsum, and the other is a carbonate of lime, akin to a marble in composition. Due to the close resemblance of the two materials, in terms colour and grain, some ambiguity in distinct identification has persisted. The gypsum alabaster or the oriental alabaster is more softer, delicate and needs care in polishing. It soon tarnishes on atmospheric exposure, and affected by dust and smoke. The carbonate alabaster is little more firmer and so more suitable for larger items. This was sourced from caves where lime water drips to form natural deposits or moulded forms. It is also called onyx-marble or alabaster-onyx, or simply as onyx. There are several types of alabaster found, including pink, white, and black.

Pietà, 1440, Alabaster, Museum Frankfurt

600px-Norbury,_Derbyshire_-_Nicholas_FitzherbertAlabaster have been modified by various treatments. To make it opaque like a marble, its translucency is reduced by immersing the completed work in a bath of water, and gradually heating, so that stone does not become dead white or chalky. The treated material is called marmo-di-Castellina. Alabaster is also tinted to accentuate the natural veins or to add colour that matches the stone or wood in the surroundings. This is done to produce make-believe coral for decorative elements like rails of staircases, handles and trims.

Alabaster_vase_turning_(5378433108)

Amenhotep I’s reconstructed alabaster chapel at Karnak

Alabaster was used as translucent panels before the advent of glass, in openings of monasteries in Mediterranean countries, like Greece, France, Italy and Spain. Alabaster cut into thin sheets is translucent enough for dull interior illumination.

740px-Beinecke-Rare-Book-Manuscript-Library-Interior-Yale-University-New-Haven-Connecticut-Apr-2014-c

Inspired by dull glow of Alabaster panels, Thin Marble panels have been used as exterior wall units for Beinecke Rare Book & Manuscript Library Yale University in New Haven, Connecticut. Large alabaster sheets have been used extensively in a Contemporary Cathedral of Our Lady of the Angels, 2002 AD, The cathedral incorporates special cooling system to prevent the panes from overheating and turning opaque.

Cathedral_of_Our_Lady_of_the_Angels-10

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WOOD RESOURCES

Post 217 – by Gautam Shah 

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Wood’s appearance, warmth to touch, its ability to be worked with simple inexpensive tools, wide range of tonal hues, grain patterns and textures make it, the most versatile craft material. The only drawback for using wood, is the effect of moisture on its structural properties and its susceptibility to decay. No two pieces of timber are similar, the great variations in structural properties, colour, texture etc., make it suitable for different uses. These wide variations in a quality put the timber to a disadvantage in comparison to many naturally available materials.

Wood products

Wood products

Wood products

Wood products

Trees can be basically classified into two groups – exogenous trees (exogens) and endogenous trees (endogens).

  • Trees may be broadly grouped into exogenous and endogenous trees according to the way in which their stem diameter increases.
  • Endogenous: are trees with inward growth, and have longitudinal fibres such as canes, bamboo, palms etc. Typically it is not possible to see any growth rings in this set of trees.
  • Exogenous: are trees with outward growth (such as additions of annual-seasonal rings), like Conifers (narrow leaves) (pine, fir), Deciduous trees (broad leaves) (teak, rose). These are used as engineering timbers.
Exogenous conifer

Exogenous conifer

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Endogenous plant Bamboo

Endogenous plant Bamboo

Exogenous plants as the name suggests grow outward. The stems are formed by successive additional layer on outside. Timber is essentially derived by the new mass formed in the cambium between the wood and the bark every year. Trees of cold climates and substantial numbers trees of warmer climates are exogenous. Rings in the trunk or branch section, and pith with medullary rays extending outwards to the bark are two distinguishing features of exogenous trees. Exogens yield timber for furniture and construction. Exogenous trees are subdivided into two main classes: broad-leaved trees and needle-leaved trees, or conifers. Broad-leaved Woods generally contain no resins, and the density or weight is greater. They are usually hard, and due to their irregular structure, net yield is lower.

temple-663126_640

640px-Commune_by_the_great_wall3

The other botanical group of endogenous trees or endogens or grow inward from a hard exterior shell or, more commonly, end-wise by the acquisition of a new joint. Endogenous trees grow by forming new fibres within the trunk interspersed with the old fibres. Old endogenous stems have older and harder wood near the surface, whereas younger and softer centre. Timber from these trees has very limited engineering applications. Examples of endogenous trees are Palms, bamboos, canes, etc. These are not broadly useful for furniture or construction work, yet have their specific advantages and uses.

waterwheel-168465_640

640px-Thonet_chairs_Wien_museum_Karlplatz

Commercial timbers of exogenous trees are classified as softwoods and hardwoods, though a very misleading nomenclature. Softwoods are timbers obtained from conifers, growing above certain altitude, and are supposed to be soft and lighter in colour. Hardwoods, are timbers that originate from the mainland and tropical areas are supposed to be hard and darker in colour. Many softwoods, though, are much harder and often of darker in shades than some of the hardwoods. Inversely many hardwoods are fairly soft and lighter in colour than some of the softwoods. Botanical names and commercial names of trees or timbers do not provide a true picture. There are multiple botanical names for the same specie adding to the confusion. Same timber is likely to be differently known commercially in various parts of the world.

Thanjavur_Palace'

Thanjavur Palace India

Timber is a very precious commodity. It takes decades to grow a commercially viable timber tree. Deforestation has become a prime issue from ecological points of view. Several countries have banned or severely curtailed and controlled the export of timber. Similarly many countries have banned import of timber to limit deforestation world wide. Many governments and local authorities discourage timber structures and other uses of timber. Government of India has enforced conditions, so that usage of timber as doors and windows and other structural purposes are nearly banned, in government schemes. Similar conditions are likely to be followed by state governments also. So over the years use of timber is likely to be severely curtailed not only due to legislation but also its difficult availability and consequent upward pricing.

Wood products

Wood Composite products

Timber grown in planned plantations is of consistent variety due to standard or a singular source of seedling or genetic derivation and grown in very controlled conditions. These results in trees with identical grain, colour and texture, belying the natural variations associated with woods.

wicker-furniture

Wood replacement products are of broadly two types. Wood-based composites such as plywood, block boards, chip and particle boards are likely to remain available, but only for a while. The availability of such products is also going to taper off in future. Wood ‘look-a-like’, make-believe, or pseudo wood products made of polymeric composites, painted, printed or layered materials are in the market.

Unlike a metal or plastic, wood is inherently a replenish-able resource, provided production and use are controlled and matched.

 

 

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