z to Zoom ratio

z to Zinc metal
Z. Symbol for impedance. Zebrano. (Wood) Zebrawood. A very
large tree, native of the west coast of Africa. Wood is hard. heavy, and tough; its light-coloured background and parallel dark-brown stripes make it valuable for unusual effects on fine furniture and paneling.
Zee bar. (Engin.) A structural-steel bar with cross-section like the letter Z. Much used in ship construction as well as in other engineering fields.
Zenter diode. Type of silicon diode with constant voltage drop ov~r wide range or reverse current. Used for voltage stabilising or as a volt­age reference level device.
Zenith adjustment. A mechanical adjustment of a magnetic tape head to obtain uniform contact with the top and bottom of the tape. Zenith refers to the forward"backward tilt­ing of the head.
Zenith-GE. Applied to multiplex stereo radio system combining major features proposed by these' two companies (U.S.A), now ge­nerally adopted throughout the world.
Zero. The numeral 0; a cipher; the lowest point.
Zero ceiling. (Aero.) Cloud level below 100 feet. Weather unfit for flying. I
Zero lift angle. (Aero.) The angle of attack of an airfoil when the angle of incidence is zero.
Zero lift line. (Aero.) A line through the trailing edge of an ai.rfoil par­allel to the direction of the wind when the lift is zero.
Zigzag rule. Derives its name from the manner of opening and clos­ing. Often referred to as a folding rule. Made up in 6-in. ~ections total from 2 to 8 ft.
Zinc. (Metal.) A bluish-white metal principally used in galvanizing and in making alloys.
Zinc chloride. (Chern.) ZnCI3. A white, deliquescent salt, obtained by the solution of zinc, or zinc oxide in hydrochloride acid, or by burning zinc in chlorine. Used as a soldering flux.
Zinc engraving or etching. (Print.) A printing plate made of zinc. The background is etched and cut away leaving the design in relief.
Zinc oxide. (Chern.) (ZnO) A white powder dried by heating zinc car­bonate. Used as a paint pigment, for medicines, and zinc salts.
Zinc sulphate. (Chern.) (ZnS04) Made by dissolving scrap zinc in sulphuric acid. It is used in calico printing, dyeing, as a drier for lin­ seed oil, in medicine, and for pre­

Zinc white to Zoom ratioserving wood and skins.
Zinc white. (Paint.) Zinc oxide used as a pigment.
Zinox. (Paint.) A hydrated oxide of zinc used in the manufacture of enamels.
Zoom. (Aero.) A short, steep climb during which the rate of climb is greater than that which can be maintained during steady flight.
Zoom lens. A lens with a variable focal length; a lens whose angle of view can be changed without mov­ing the camera.
Zoom ratio. A mathematical expres­sion of the two extremes of focal length available on a particular zoom lens.