Guide to Gyroscopk

Guide bearings to Gutter

the antique and usually carved and gilded.
Guide bearings. (Mach.) Bearings which consist of a channel or groove in which parts slide; e.g., crosshcad bearings.
Guide pins. (Plast.) Devices that main­tain proper alignment of force plug and cavity as the mold closes. Guide rail A rail placed on lhe inside of the main rail of a railroad track to guide the wheel flanges; used principally on curves and bridges.
Guides. (Print.) Used to place lhe sheets against so that the printing may be in exactly the same place on each sheet.Guides are adjustable, and may be set and locked in any required position.
Guilloche. (Arch.) An ornament in lhe fonn of bands or strings characteri­zed by a wavy interlacement of the main motifs, leaving circular open­ings filled with round ornaments.
Guillotine cut..(Bookblldg.) Paper cut or trimmed by a machine known as the "guillotine."
Gum bloom. (Paint alld Lacquer) A transparent haze or lack of normal gloss, due to use of incorrect re­ducer.
Gumming test for oils. This ~est may be used to measure the extent to which oils will carbonize in gas­engine cylinders. It is made by treat­ing oil with acids, which brings about the changes that take place in an oil when used."
Gums. t Chell!. Plast.) Viscous vege­table secretions which harden but, unlike resins, arc water soluble. The lime is often applied in the varnish industry to natural resins such as copal.
Gumwood. A medium hard, dark-col­oured wood with grain effect simi­lar to Circassian walnut; used ex­tensively in the manufacture of furniture and the interior trim in buildings.
Gun cotton. (Chern.) A highly explo­sive mixture obtained by treating cotton with nitric and sui ph uric acids.
Gun lathe. (Mach.) A large lalhe used for turning and boring cannons.
Gun metal. Alloy of copper and tin; a bronze once much used for can­non.
Gunning. (Aero.) To race an airplane engine. A rapid, jerky application of the throttle.
Gunpowder. (Chern.) An explosive mixture of saltpeter, charcoal and sulphur; it may be eilher black or brown in colour.
Gunters chain. A surveyor's measure "66 ft. in length. It consists of 100 inks each being 7.92 in. long.
Gusset. (£lIgill.) An angle bracket or brace used to stiffen a corner or angular portion of a piece of work.
Gutta-percha. The gum is obtained from lhe milk juice of sever-al trees found native in the East Indies. Gutta-percha has many uses, the most important being for insulat­ing.
Guttae. (Arch.) Small cylindrical or cone-shaped pendants used to ornament the Doric entablature.
Gutter. (Arch.) A channel along the caves of a house to carry off rain.

Gutter bracket to Gyroscopk turn indicator
(Masonry) a bricked or paved sur­face in the street adjoining the curb. (Bookmkg.) Inner margin pr: a bound book.
Gutter bracket. (Arch.) Small metal brackets used to support hanging gutters.
Guy. (Engin.) Wife, rope, or chain used to steady, support, or hold in place a boom, - mast, pole, chimney, or other similar piece of construction.
Guy rope. (Engin.) Galvanized rope consisting of 6 strands, 7 wires each, and a hemp core.
Gypsum. (Bldg., Paint, Plaster, and Pot.) Hydrous sulphate of calcium (CaS042H20), colourless when pure. When it is heated slowly, part of the water is driven off, the result­ing product being known as "Pias­ter of Paris."
Gyrate. To turn on an axis of rotation. Gyro horizon. A gyroscopic instru­ ment that indicates the lateral and

longitudinal attitude of the airplane by simulating the natural horizon.
Gyro-puot.. (Aero.) A gyroscopic and mechanical device which automatically flies an -airplane.
Used to relieve pilots of the fatigue or routine cross-country pilotage.
Gyro-plane. (Aero.) A type of rotor plane whose support in the air is chiefly derived from airfoils ro­tated about an approximately ver­tical axis by a~rodynamic forc~s, and in which the £ifi on the oppo­:;ite sides of the plane of symmetry is equa-lized by rotation of the blades about the blades' axis.­
Gyroscope. (phys.) A flywheel mounted inside supporting rings which are pivoted to permit rota­tion in any direction. Used to sta­bilize ships and steer aircraft.
Gyroscopk turn indicator. (Aero.) A turn indicator dependent on gyro­scopic action.