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An apparatus for making spectroheliograms, consisting of a spectroscopic camera used in combination with a telescope, and provided with clockwork for moving the sun's image across the slit. -- Spec`tro*he`li*o*graph"ic (#), a.

a picture and reproducing its image as a positive or negative. The transmitter includes a camera obscura and a row of minute selenium cells. The receiver includes an oscillograph, ralay, equilibrator, and an induction coil the sparks from which perforate a paper with tiny holes that form the image.

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.

a combination of lenses specially designed to give a large image of a distant object in a camera of relatively short focal length.

istant objects in more enlarged form than is possible by the ordinary means, usually 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.

frame or stand, usually jointed at top, for supporting a theodolite, compass, telescope, camera, or other instrument. Tripod of life, or Vital tripod (Physiol.), the three organs, the heart, lungs, and brain; -- so called because their united action is necessary to the maintenance of life.