Page:Dictionary of aviation.djvu/192

 168 DICTIONARY OF AVIATION

peripheral pg'zifa-zal adj. [also spelt periferal] of the pe- nfery: as, *penferal speed.

periphery-line pa'zifazi^am n. [also spelt periferyfline] the line of the penfery of a balloon'.

peripteral pa'zipta-zal adj. ef or pertaining to the pe- nptery; situated or occurring in the neighborhood of a wing or other aerofoil : as, the *peripteral system of flow.

peripteral area, the area of the cress^section of a perip- teral zone : as, the *penpteral areas of adjacent blades overlap.

peripteral motion, the motion of the air or other fluid in the immediate vicinity of a moving wing or aerofoil; the forced wave or system of air^currents about a moving aero- feil.

peripteral theory, theory regarding wing^form and the resultant fluid motions in the peripteral zone; dectjin as to the shapes of aerofoils and the systems of currents due to their motion thru the air or other fluid.

peripteral zone, the zone or sfere of influence of an aero- foil; the tjact or region of fluid^fild space which surrounds an aerofoil.

peripteroid pa'zipto^oid adj. like the penptery; resembling that which occurs round about the wing or aerofoil of a natural or artificial flyer : as, *penptereid motion.

periptery pa'ziptD-zri n. the region round about the wing, or in the vicinity of the aerofoil, of a natural or artificial flyer : as, an unstable *penptery.

perspectometer ,pi3zspek'tmi-t3z n. a device for marking dimensions or distances en a fotograf, or perspectiv draw- ing, as an aid in interpretation or in judging perspectiv.

petaurist pi'tc:-rist n. a flying^falanger; a f lying^opossum ; an Australian f lying^squirrel ; an acrobat; one of the Petau- rista.

petrol 'petrel, pi'tr.ool n. a volatil inflammable liquid, one of the first products in the distillation of crude petroleum, used in the motors of automobiles and flyers; petroleum spirit; gasoline.

petrol-depot 'petr^dii-po n. a depot or storehouse where petjol or gasoline is kept for the use of airships.

petrol-tank 'petr^tsenk n. the gasoline^tank of an airship.

phase-curve 'feez,ki3:zv n. [also spelt phase curve, fase? c\wv\ a curv or curvd line drawn thru the mid^fase points, or points of greatest flight^velocity, in a, series of fugeid curvs.

photogrammeter ,fot3'gsemi-t3z n. [also spelt fotogram- meter] a fotografic camera used in mesuring the location

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