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An instrument for measuring the curvature of spherical surface, as of lenses for telescope, etc.

A small telescope for viewing distant terrestrial objects.

rod used to measure the distance of the place where it stands from an instrument having a telescope, by observing the number of the graduations of the rod that are seen between certain parallel wires (stadia wires) in the field of view of the telescope; -- also called stadia, and stadia rod.

central portion with a surrounding border of lighter shade, and usually seen only by the telescope, but sometimes by the naked eye. They are very changeable in their figure and dimensions, and vary in size from mere apparent points to spaces of 50,000 miles in diameter. The term sun spots is often used to include brig…

verse, with the eye or with an instrument of observation; as, to sweep the heavens with a telescope. To sweep, or sweep up, a mold (Founding), to form the sand into a mold by a templet, instead of compressing it around the pattern.

ions of objects seen through the prisms are increased or diminished; -- called also prism telescope. Sir D. Brewster.

An instrument used for measuring the distance of an object from an observer; as, a telescope with a micrometer for measuring the apparent diameter of an object whose real dimensions are known.

A combination of the camera lucida and telescope for drawing and measuring distant objects. -- Tel`e*me*trog"ra*phy (#), n. -- Tel`e*met`ro*graph"ic (#), a.

An instrument of such focal length that it may be used as an observing telescope for objects close at hand or as a long-focused microscope.

ually by a camera provided with a telephoto lens or mounted in place of the eyepiece of a telescope, so that the real or a magnified image falls on the sensitive plate.

A polariscope arranged to be attached to a telescope. Lockyer.

A sight consisting of a small telescope, as on a compass or rifle.

Of or pertaining to a telescope; performed by a telescope.

In a telescopical manner; by or with the telescope.

One who uses a telescope. R. A. Proctor.

The art or practice of using or making telescopes.

A spectroscope arranged to be attached to a telescope for observation of distant objects, as the sun or stars. Lockyer.

Adapted for the observation of objects on land and on the earth; as, a terrestrial telescope, in distinction from an astronomical telescope. -- Ter*res"tri*al*ly, adv. -- Ter*res"tri*al*ness, n.

. -- Test object (Optics), an object which tests the power or quality of a microscope or telescope, by requiring a certain degree of excellence in the instrument to determine its existence or its peculiar texture or markings. -- Test paper. (a) (Chem.) Paper prepared for use in testing for certain substances by being…

The passage of a heavenly body over the meridian of a place, or through the field of a telescope.