Abstract: A binocular reflecting telescope having two Cassegrain or Schmidt-Cassegrain reflecting mirror units having the same aperture and the same focal length; each unit includes a concave primary mirror and a convex secondary mirror provided opposite to each other along each of two parallel first optical axes; the telescope also having two erect real image forming devices each including a combination of place mirrors for guiding a ray of light out of the first optical axis from a point between the primary mirror and the secondary mirror. Two eyepiece units are provided and are rotatable about the optical axes of the light rays guided out of the two erect real image forming devices.

Abstract: An equatorial mount for supporting a binocular reflecting telescope having two Cassegrain or Schmidt-Cassegrain reflecting mirror units having the same aperture and the same focal length. The equatorial mount includes a pedestal, a polar shaft (first shaft) supported obliquely by the pedestal. A second shaft is rotatably supported in a support barrel coupled to the polar shaft. A third shaft is rotatably supported in a second support barrel provided at the bottom end of the first support barrel. Counterweights are screwed onto a threaded rod so as to extend from the free end of a V-shaped crank which is mounted on the free end of the second shaft. Another counterweight is screwed onto another threaded rod mounted inside of the crank and extends in the same direction as the crank. The equatorial mount has a greater degree of freedom of rotation compared with a German-style equatorial mount, because it has the third shaft.

Abstract: A terrestrial globe for observing the polar areas. The globe is made from a pair of semi-spherical members put together along a vertical plane into a spherical body. The globe is supported on a pivotally supported semi-circular member which opens upwardly. The semi-spherical members are rotatable together with each other around a vertical polar shaft, and independently of each other around horizontal rotary shafts. The polar shaft is formed at both ends with eccentric shank portions so as to allow one of the semi-spherical members at one side to rotate freely around the rotary shaft while preventing the one at the other side from rotating around the rotary shaft. When it is desired to turn the spherical body upside down, that is, to reverse the positions of the South Pole and the North Pole, the semi-spherical member at the shank-free side is rotated by 180.degree. around the rotary shaft. Then the spherical body is turned by 180.degree.