Terminology

Leonurdo, Vol. 5, p. 355. PergamonPress 1972. Printed in Great Britain TERMINOLOGY The terms defined below were selected from artists’ articles and notes published in the previous issue of Leonardo. Each definition is followed by an indication of the volume and page number of Leonardo on which the term first appears. The terms were not found in the art dictionaries included in the list in Leonardo5,77 (1972) or they are used in a new sense. Some are terms that have been carried over into the field of art from the natural and social sciences,from mathematics and from technology. Numbers in brackets, e.g. [lo, 151, refer to the dictionaries mentioned above. The definitions are not presumed to be unassailable. The Editors would, therefore, welcome the comments of readers on the definitions presented. 1. Blowtorch-a small portable apparatus for expellinga combustible fluid under pressure from a nozzle to produce an intensely hot flame (5, 205 ~ 4 1 ) . 2. Cure (in chemical engineering)-To effect a chemical conversion in a polymeric substance to produce a more rigid state. Rubber is cured during its vulcanization; a thermosetting resin is cured in its mold (5, 197; cf. J. Delorme, Dictionnaire des Mati2res Plastiques (Paris: Amphora, 1958)). 3. Electromagnetic wave (in physics)-The means by whichradiant energyis transferred through space or matter. Heat rays, light rays, radio waves and X-rays are examples of electromagnetic waves (5, 193 [lo]). 4. Exothermtemperature (inplastics technology)-The temperature of a mass of thermosetting material releasing heat of chemical reaction during curing. The peak exotherm temperature is the maximum temperature reached before the material begins to cool (5, 197)(cf. Cure, above). 5. Gantry (in space technology)-A movable structure with platforms at different levels used for erecting and servicing rocket vehicles before launching (5, 201 [15]). 6. Gunned concrete (in architecture)-A construction material composed of cement, sand or crushed slag and water mixed together and forced through a cement gun by pneumatic pressure (U.S. trademark: Gunite). (5, 205; cf. A. E. Burke, J. R. Dalzell and G. Townsend, Architectural and BuildingTradesDictionary (Chicago:American Technical Society, 1955)). 7. Lenticular-Formed like a convex lens, i.e. with two faces of a shape curved outwards (5, 193 121). 8. Nonferrous(in metallurgy)-Relating to metals other than iron (5, 197 [15]). 9. Oxidize (in chemistry)-To combine chemically with oxygen or any electro-negative element or radical, removing one or more electrons from the atom, ion or molecule (5, 198 [151;cf. R. J. Gettens and G. L. Stout, Painting Materials. A Short Encyclopaedia(New York: Dover, 1966)(cf. Oxide, Leonardo 4,288 (1971)). 10. Parallelepiped(inmathematics)-A solidformed by six plane faces that are parallelograms. There are three pairs of parallel faces (5,205 [12, 14, 151). 1 1 . Polyvinyl alcohol (in chemistry)-A synthetic resin obtained by the hydrolysis of polyvinylacetate. It is used as an organic-solvent-resistant coating and also as an additive in polymer paint emulsions (5, 195;cf, A. G. Roberts, Organic Coatings (Washington , D.C. :National Bureau of Standards, 1968)). 12. Relativehumidity(in meteorology)-A measure of the water content of air. Expressed as a percentage , it is the amount of water actually present in the air divided by the greatest amount that could be present at the same temperature and multiplied by 100.(5, 195 [2, lo]). 13. Sculpture-architecture-A type of architectural design especially incorporating sculptural qualities in addition to functional aspects (5, 205). 14. Sculpture-sign-A term coined by P. Szekely for a sculpture having a basic form whose meaning is suggested to the viewer without prior instruction (5, 204). 15. Sculpture-urbanism-A type of urban design especially incorporating sculptural qualities in addition to functional aspects (5, 207). 16. Styrene (in chemistry)-A liquid organic chemical used chiefly in making synthetic rubber, synthetic resins and plastics (5, 196 [15]) (cf. Polystyrene , Leonardo 4,288 (1971) and G. A. Agoston, Health and Safety Hazards of Art Materials, Leonardo 2,375 (1969)). 355 ...