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Of or pertaining to Galileo; as, the Galilean telescope. See Telescope.

A false image formed in a telescope by reflection from the surfaces of one or more lenses. Ghost moth (Zoöl.), a large European moth (Hepialus humuli); so called from the white color of the male, and the peculiar hovering flight; -- called also great swift. -- Holy Ghost, the Holy Spirit; the Paraclete; the Comforter;…

or glass globes. Many varieties are known. Called also golden fish, and golden carp. See Telescope fish, under Telescope.

he Great, and named after the ancient Greek scales, as Dorian, Lydian, etc. -- Gregorian telescope (Opt.), a form of reflecting telescope, named from Prof. James Gregory, of Edinburgh, who perfected it in 1663. A small concave mirror in the axis of this telescope, having its focus coincident with that of the large ref…

tion of two stars too far apart to be easily measured in the field of view of an ordinary telescope.

A telescope or instrument for viewing the sun without injury to the eyes, as through colored glasses, or with mirrors which reflect but a small portion of light. -- He`li*o*scop`ic, a.

Of or relating to Sir William Herschel; as, the Herschelian telescope.

viding the equator into spaces of 15º, or one hour, each. (b) A circle upon an equatorial telescope lying parallel to the plane of the earth's equator, and graduated in hours and subdivisions of hours of right ascension. (c) A small brass circle attached to the north pole of an artificial globe, and divided into twenty…

by, Christian Huyghens, a Dutch astronomer of the seventeenth century; as, the Huyghenian telescope. Huyghenian eyepieceSee under Eyepiece.

or the retina of the eye, and viewed directly by the eye, or with an eyeglass, as in the telescope and microscope; the likeness of an object formed by reflection; as, to see one's image in a mirror. Electrical image. See under Electrical. -- Image breaker, one who destroys images; an iconoclast. -- Image graver, Ima…

bulæ (Astron.), nebulæ of a cloudlike appearance, which have not yet been resolved by the telescope into stars. Sir W. Herschel.

arly horizontal glass tube, or a circular box with a glass cover. -- Surveyor's level, a telescope, with a spirit level attached, and with suitable screws, etc., for accurate adjustment, the whole mounted on a tripod, for use in leveling; -- called also leveling instrument. -- Water level, an instrument to show the l…

An instrument, used with a telescope or microscope, for measuring minute distances, or the apparent diameters of objects which subtend minute angles. The measurement given directly is that of the image of the object formed at the focus of the object glass. Circular, or Ring, micrometer, a metallic ring fixed in the foc…

eing worn in ancient times. Shak. -- Naked eye, the eye alone, unaided by glasses, or by telescope, microscope, or the like. -- Naked-eyed medusa. (Zoöl.) See Hydromedusa. -- Naked flooring (Carp.), the timberwork which supports a floor. Gwilt. -- Naked mollusk (Zoöl.), a nudibranch. -- Naked wood (Bot.), a large…

rs. True nebulæ are gaseous; but very distant star clusters often appear like them in the telescope.

and, most frequently, to the mathematical theory of universal gravitation. -- Newtonian telescope (Astron.), a reflecting telescope, in which rays from the large speculum are received by a plane mirror placed diagonally in the axis, and near the open end of the tube, and thrown at right angles toward one side of the…

of a transitive verb. Object glass, the lens, or system of lenses, placed at the end of a telescope, microscope, etc., which is toward the object. Its office is to form an image of the object, which is then viewed by the eyepiece. Called also objective. See Illust. of Microscope. -- Object lesson, a lesson in which ob…

The eyepiece of an optical instrument, as of a telescope or microscope.

llet dancer, whence the popular name. Called also dancing girls. -- Opera glass, a short telescope with concave eye lenses of low power, usually made double, that is, with a tube and set of glasses for each eye; a lorgnette; -- so called because adapted for use at the opera, theater, etc. -- Opera hat, a gentleman's…

A telescope with a diagonal eyepiece, suspended vertically in gimbals by the object end beneath a fixed diagonal plane mirror. It is used for delineating landscapes, by means of a pencil at the eye end which leaves the delineation on paper.