Page:Dictionary of aviation.djvu/170

 146 DICTIONARY OF AVIATION

as of wood, aleng which a flying-machine is run in launch- ing it into the air; a monorail launchmg-tack.

launching-scow 'ic:n-t$irj,skau n. a scow or large flat-bet- tomd boat used as a launching-platferm for a flyer.

launching-staff 'lc:n-t$irj,sta:f n. a staff used for launching an experimental aerofoil into the air. It consists of a straight red a few feet in length, capt with a small rectan- gular platen en which the aerofeil is carried; a launching^ stick.

launching-stick 'Icrn-tSir^stik n. a stick or stick-like device for launching an experimental aeroplane or aerofeil into the air; a launching-staff.

launching-track 'lc:n-t$irj,taek n. a tgack of railway aleng which a flying-machine is run in launching it into the air.

launching-vehicle 'Jc:n-t$irj,vii-i-k9l n. a vehicle, such as an automobile or a boat, upen which a flying-machine may be mounted and moved aleng so as to launch it into the air.

law !c: n. a principle or preposition which expresses the con- stant or regular erder of certain fenemena; a general for- mula or rule to which all things or events of a given class tend to conform.

Allen's law, the normal law of skin-friction as stated by H. S. Allen.

Ferrers law, the law or principle, as formulated by William Ferrel in 1854, that a body moving in any di- rection aleng the s&face of the earth is deflected toward the right in the northern hemisfere and toward the left in the southern hemisfere by an amount which varies di- rectly as the velocity of the body and as the sine of the latitude.

Gallon's antlcyclonic law, see under anticyclonic. Langley's law, the law or principle that (under certain conditions) the power required to propel an aeroplane diminishes indefinitly as the speed increases.

law of Avanzini, the law or principle that as the speed of an inclined or oblique plane moving thru a fluid increases, and as the angle of incidence becomes less, the center of pressure moves toward the rear of the plane.

law of slip, the law to which the slip of a propeller or other selid body which is moving thru a fluid conforms ; the principle that, at low pressures, the relativ motion of a gas aleng a selid surface is the same as tho the selid surface were removed to a distance equal to twice the mean free path of the gaseous particles and were replaced by a layer of gas at rest.

law of storms, the law or principle that the distance of

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