In most forging an upper die is forced against a heated workpiece posi¬ tioned on a stationary lower die. To increase the force of the blow, power is sometimes applied to augment gravity. The number of blows struck is carefully gauged by the operator to give maximum effect with mini¬ mum wear on the die. Forging presses employ hydraulic or mechanical pressure instead of blows; most can exert only a few hundred tons of pressure, but giant presses, used for forging parts of jet aircraft, are capable of up to 50,000 tons of pressure. See also drop forging.
form In the philosophy of Plato and Aristotle the active, determining principle of a thing. The term was traditionally used to translate Plato’s eidos, by which he meant the permanent reality that makes a thing what it is, in contrast to the particulars that are finite and subject to change. Each form is the pattern of a particular category of thing in the world; thus, there are forms of human, stone, shape, colour, beauty, and justice. Whereas the physical world, perceived with the senses, is in constant flux and knowledge derived from it restricted and variable, the realm of forms, apprehensible only by the mind, is eternal and changeless. Particular things derive what reality they have by “participating” in, or imperfectly copying, the forms. Aristotle rejected the abstract Platonic notion of form and argued that every sensible object consists of both matter and form, neither of which can exist without the other. For Aristotle, the matter of
Woods forget-me-not [Myosotis sylvat¬ ica)
INGMAR HOLMASEN
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694 i formal system ► Forster
a thing consists of those of its elements which, when the thing has come into being, may be said to have “become” it; the form of a thing is the arrangement or organization through which such elements have become the thing in question. Thus a certain lump of bronze is the matter that, given a certain form, becomes a statue or, given another, becomes a sword. The Aristotelian concept of form was adapted and developed by St. Tho¬ mas Aquinas and other scholastic philosophers. The Enlightenment phi¬ losopher Immanuel Kant used the notion of form to describe the mentally imposed conditions of sensible experience, namely space and time.
formal system In logic, a formal language together with a deductive apparatus by which some well-formed formulas can be derived from oth¬ ers. Each formal system has a formal language composed of primitive symbols that figure in certain rules of formation (statements concerning the expressions allowable in the system) and a set of theorems developed by inference from a set of axioms. In an axiomatic system, the primitive symbols are undefined and all other symbols are defined in terms of them. In Euclidean geometry, for example, such concepts as “point,” “line,” and “lies on” are usually posited as primitive terms. From the primitive sym¬ bols, certain formulas are defined as well formed, some of which are listed as axioms; and rules are stated for inferring one formula as a conclusion from one or more other formulas taken as premises. A theorem within such a system is a formula capable of proof through a finite sequence of well-formed formulas, each of which either is an axiom or is validly inferred from earlier formulas.
formaldehyde \f6r-'mal-d3- l h!d\ or methanol Vme-tho-.nalX Sim¬ plest aldehyde, chemical formula HCHO. Formaldehyde (37%) in water solution, called formalin, is used as a preservative, an embalming agent, and a disinfectant. Large amounts of formaldehyde are used in the manu¬ facture of various familiar plastics. Bakelite (the first completely synthetic plastic) is the trademark for formaldehyde and phenol polymer, and For¬ mica is the trademark for formaldehyde and urea polymer. The reaction of formaldehyde with proteins (called amino formylation) leads to its use in the tanning industry and for treating various vegetable proteins to ren¬ der them fibrous.
formalism See New Criticism
Formalism or Russian Formalism Russian school of literary criti¬ cism that flourished from 1914 to 1928. Making use of the linguistic theories of Ferdinand de Saussure, Formalists were concerned with what technical devices make a literary text literary, apart from its psychologi¬ cal, sociological, biographical, and historical elements. Though influenced by the Symbolist movement, they sought to make their analyses more objec¬ tive and scientific than those of the Symbolists. The movement was con¬ demned by the Soviet authorities in 1929 for its lack of political perspective. Later it became influential in the West, notably in New Criti¬ cism and STRUCTURALISM.
Forman, Milos (b. Feb. 18, 1932, Caslav, Czech.) Czech-U.S. film director. He began his career as a scriptwriter, then directed his first fea¬ ture film in 1964. Success followed with the ironic comedies Loves of a Blonde (1965) and The Fireman’s Ball (1967). He moved to the U.S. in 1969 and successfully applied his light touch to the generation gap in Taking Off (1911), then triumphed with One Flew over the Cuckoo’s Nest (1975, Academy Award). He directed successful screen adaptations of theE.L. Doctorow novel Ragtime (1981) and the stage play Amadeus (1984, Academy Award); his later films include Valmont (1989) and The People vs. Larry Flynt (1996).
formes fixes \'f6rm-'feks\ Principal forms of music and poetry in 14th- and 15th-century France. Three forms predominated. The rondeau fol¬ lowed the pattern ABaAabAB\ A (a) and B (b) represent repeated musical phrases; capital letters indicate repetition of text in a refrain, while low¬ ercase letters indicate new text. The ballade employed the pattern aabC. The virelai used the pattern AbbaA. The trouvere Adam de la Halle (b. c. 1250) wrote the first polyphonic settings of the formes fixes. Guillaume de Machaut wrote both text and music for many monophonic and polyphonic chansons in the formes fixes. Later composers, including Guillaume Dufay, favoured the rondeau.
formic acid Simplest carboxylic acid, chemical formula HCOOH. It is secreted by some insects, especially red ants (its name comes from the Latin word for ant), in their bite or sting. It has many industrial uses, in textile and leather manufacture, as an industrial solvent, and as an inter¬ mediate.
Formosa See Taiwan Formosa Strait See Taiwan Strait
formula weight Sum of the atomic weights of all atoms in a chemical formula. The term is generally applied to a substance that consists of ions (see ionic bond) rather than individual molecules (and thus does not have a molecular weight). An example of such a substance is sodium chloride (table salt). Such a substance’s chemical formula describes the simplest ratio of the number of atoms of the constituent elements. See also stoichi¬ ometry.
Fornes Vfor-nas\, Maria Irene (b. May 14, 1930, Havana, Cuba) Cuban-born U.S. dramatist. Her family moved to the U.S. in 1945, and she became a painter before beginning to write plays in the early 1960s. She wrote some 35 stage works and directed her own works as well as classic drama. Her innovative dramas have made her one of the most suc¬ cessful and frequently produced of Off Broadway playwrights. Her best- known play, Fefu and Her Friends (1977), explores women’s relationships with one another.
Forrest, Edwin (b. March 9, 1806, Philadelphia, Pa., U.S.—d. Dec. 12, 1872, Philadelphia) U.S. actor. He made his stage debut in Philadel¬ phia in 1820. He played Othello in New York (1826) to great acclaim and became known for his Shakespearean roles. His feud with the English actor William Macready sparked the so-called Astor Place riot (1849), in which Forrest’s supporters mobbed the theatre where Macready was appearing. The militia was called out, the rioters attacked, and the militia fired, killing 22 and wounding 36. Forrest’s reputation never fully recov¬ ered; it was further damaged when he filed a divorce suit on grounds of adultery.
Forrestal, James V(incent) (b. Feb. 15, 1892, Beacon, N.Y., U.S.—d. May 22, 1949, Bethesda, Md.) U.S. secretary of defense (1947- 49). After serving in naval aviation in World War I, he resumed his con¬ nection with a New York City investment firm, of which he became president in 1938. Appointed undersecretary of the navy in 1940, he directed the huge naval expansion and procurement programs of World War II. He became secretary of the navy in 1944. Appointed the first sec¬ retary of defense in 1947, he began to reorganize and coordinate the armed services. He resigned in 1949. Suffering from a depression similar to battle fatigue, he entered Bethesda Naval Medical Center; soon after, he plunged to his death from a window.